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THEORETICAL PHYSICS (chair: Fabrizio Piacentini)

• 10:00 - 10:25 Matteo Tuveri (University of Cagliari)
  "Emergent Gravity from an Augmented Variational Principle"

  In the last decade, physical and geometrical investigations about the relationship between horizon thermodynamics and gravitational dynamics suggests that gravity could be an emergent phenomenon. Among the others, Padmanabhan's theory of “emergent gravity” focus on the concept of spacetime as an effective macroscopic description of a more fundamental microscopic theory (“atoms of spacetime”) at the Planck scales, thus reconciling the large scale description of gravity and the small one of quantum physics. According to Padmanabhan's work, since in standard thermodynamics quantities like temperature and entropy arise from the existence of some internal degree of freedom of the system, the possibility to attribute some temperature and some entropy to spacetime (black holes) is an indication of some underlying coarse-grained structure of our universe. So, given a certain region of spacetime, it is possible to define an entropy functional in terms of suitable parametrized microscopic degrees of freedom. In particular, the minimization of this functional leads to Einstein equations. However, this procedure is not completely clear from a physical and mathematical point of view. Thus in this work, a direct and non-trivial link between Padmanabhan's entropy used in emergent gravity and standard General Relativity action is established. To do that, Augmented Variational Principles (AVP) will be used. We shall also discuss how this link accounts for the details of the variation of Padmanabhan's action based on gravitational entropy. It will also clarify the role of the background metric and its non-dynamical role.

• 10:25 - 10:50 Andrea Orta (LMU Munich)
  "NMHV tree-level scattering amplitudes from the amplituhedron"

  In recent years it has been proposed that any N=4 super Yang-Mills planar amplitude can be understood as the volume of a generalized polytope, called amplituhedron. In my talk I will describe how the symmetries of the problem, in particular a set of partial differential equations obeyed by the amplitude, are enough to fully constrain the amplituhedron volume corresponding to next-to-maximally-helicity-violating (NMHV) tree-level amplitudes. The advantage of our representation is that it is independent of any triangulation of the amplituhedron.

• 10:50 - 11:15 Edgardo Franzin (University of Cagliari and INFN)
  "Testing Strong Gravity with Gravitational Waves and Love Numbers"

  The LIGO observation of GW150914 has inaugurated the gravitational-wave astronomy era and possibility of testing gravity in extreme regimes. While distorted black holes are the most convincing sources of gravitational waves, similar signals might be produced also by other compact objects. In particular, I will discuss what the gravitational-wave ringdown could tell us about the nature of the emitting object, and how measurements of the tidal Love numbers could help us in understanding the internal structure of compact dark objects. In fact, the ringdown signal from a binary coalescence is not the conclusive proof for an event horizon, the defining property of black holes. I will show that an object compact enough to possess a light ring displays a similar ringdown stage, even if its quasinormal-mode spectrum is completely different from that of a black hole. The differences between black holes and exotic compact objects appear only at late times. Another way to probe these compact dark objects and understand their internal structure is through the measurements of the tidal Love numbers, which encode the deformability of a self-gravitating object immersed in a tidal environment. Love numbers for black holes in general relativity are identically zero, while this is not the case for black holes in modified theories of gravity and for other exotic compact objects such as boson stars and gravastars.

ASTROPHYSICS & COSMOLOGY (1) (chair: Rugiada Cuccaro)

• 11:35 - 12:00 Riccardo Murgia (SISSA, Trieste)
  "Constraints on the coupling between dark matter and dark energy from CMB data"

  The investigation of the cosmic microwave background (CMB) temperature and polarization anisotropies is a powerful tool to test the standard cosmological model and understand the nature of dark matter and dark energy. Since the gravitational effects of dark energy and dark matter are opposite, i.e. gravitational repulsion vs gravitational attraction, even a small change of their relative densities can significantly affect cosmological dynamics. Whereas interactions between dark components and ordinary matter are heavily constrained by observations, we cannot exclude a coupling between dark energy and dark matter, given that we do not know the true nature of either of them. In this talk I will discuss the intriguing case of a phenomenological non-gravitational coupling in the dark sector, where the interaction is parameterized as an energy transfer either from dark matter to dark energy or the opposite. The two models are constrained by a whole host of updated cosmological data: CMB temperature and polarization anisotropies, high-redshift supernovae, baryon acoustic oscillations, redshift space distortions and gravitational lensing. Both models are found to be compatible with all cosmological observables, but in the case where dark matter decays into dark energy the tension among CMB data, low-redshift measurements of the Hubble parameter and cluster distribution observations, already present for standard cosmology, increases, mostly as a consequence of the higher amount of dark matter at early times, which leads to a stronger clustering during the evolution. Instead, when dark matter is fed by dark energy, the predicted values of the Hubble parameter and the variance of the matter distribution nicely agree with their local determinations, leading to a full reconciliation of the tension between high- and low-redshift observations. A non-zero coupling between dark energy and dark matter, with an energy flow from the former to the latter, appears therefore to be in better agreement with cosmological data.

• 12:00 - 12-25 Francesco Forastieri (University of Ferrara)
  "Planck constraints on sterile neutrinos with secret interactions"

  Short baseline laboratory (SBL) anomalies have shown preference for light sterile neutrinos with eV mass. These particles, if confirmed, would be produced in the Early Universe and would add their contribution to the relativistic energy density basically increasing the effective number of extra relativistic species. It has been showed that when the matter potential produced by the sterile interactions becomes smaller than the vacuum oscillation frequency, sterile neutrinos are plentifully produced by the scattering effects in the sterile neutrino sector. This behaviour, however, leads to an $\Delta N_{eff} \sim 1$ which is in tension at $3-5 \sigma$ with the actual constraints given by the latest Cosmic Microwave Background radiation (CMB) observations. In order to avoid the thermalization of eV sterile neutrinos in the early Universe, secret interactions between sterile and active sectors mediated by a massive vector boson ($M_X < M_W$) have been proposed. In particular, interactions mediated by a gauge boson having $M_X < 10 MeV$ would suppress the sterile neutrino productions for $T > 0.1 eV$ and seem to save the cosmological constraints coming from big-bang nucleosynthesis (BBN) and mass bounds. In this framework, cosmological observations represent a powerful tool to constrain neutrino physics complementary to laboratory experiments, in particular, observations of the CMB have the potential to constrain the properties of relic neutrinos, as well as of additional light relic particles in the Universe. In my presentation I will show results and constraints on this model, in particular on the strength of the interaction using CMB Planck 2015 data and possibly in combination with other astrophysical and cosmological probes.

• 12:25 - 12:50 Linda Polastri (University of Ferrara)
  "CMB low multipole alignments in the ΛCDM and Dipolar models"

  Focusing on the large scales that are of interest to Cosmology, the universe appears almost the same, regardless of the direction we observe. If we also postulate that we do not occupy a privileged place in the universe, we can state that the universe is homogeneous, at large scales. This is also known as the cosmological principle. The discovery of the Cosmic Microwave Background radiation (CMB), in 1964, gave credibility to the ΛCDM model based on the cosmological principle: on large scales the universe appears homogeneous and isotropic. This radiation is, in fact, isotropic to great degree (1 part in 10 5 ). Starting from the end of eighties, technological developments have allowed precision measurements: a NASA satellite COBE (1989-1993) measured the frequency spectrum of the CMB and discovered CMB anisotropies; another NASA satellite WMAP, (2001-2010) and a ESA satellite, Planck (2009-2013), have measured the angular power spectrum of these anisotropies with increasing accuracy. High quality measurements of the CMB anisotropy, such as those provided by WMAP and Planck, allow us to use the CMB to further test the cosmological principle. In accordance with this principle the CMB anisotropies must be distributed in an isotropic way, i.e do not have preferred directions. The data collected by WMAP and Planck are suggesting that some preferred directions might exist. It is not known yet if they are due to a statistical fluke, to not perfectly removed systematic effects or if they are hinting to some new mechanism possibly happened in the very early universe. I studied in detail the alignment between the quadrupole and octupole of CMB anisotropies. I have evaluated the significance of this anomaly not only for the ΛCDM model but also for the so-called Dipolar model, which is a phenomenological cosmological model that postulates that isotropy is broken on large scales, due to the presence of a long-wavelength modulation over the field. This model provides a possible explanation for another anomaly, called power asymmetry, consisting in the fact that the CMB fluctuations appear to be different in power in one hemisphere with respect to the other. In order to perform my statistical analysis I used a particular mathematical tool, the multipole vector formalism. The multipole vectors (also knows as Maxwell vectors) are an alternative representation to the standard spherical harmonic expansion and form an irreducible representation of the rotation group SO(3) so they provide a basis for expanding any scalar function on the sphere. It is possible to show that they contain information about the phase of the a `m co- efficients. What makes them very useful is the fact that starting from vectors is trivial to construct observables which are invariant under rotation (an therefore under frame of reference): it is sufficient to combine them with scalar products. I analysed eight estimators: six for the alignment between the quadrupole and the octupole. These estimators are evaluated independently with respect to one another for the two before mentioned models: the ΛCDM and the Dipolar. I analysed three CMB maps obtained from the WMAP experiment: WMAP ILC 5 year, WMAP ILC 7 year and WMAP ILC 9 year, and two CMB maps coming from the Planck experiment: SMICA and NILC. I developed two Monte Carlo (MC) simulation codes: one for each model considered. The purpose of these MC codes is to generate values for the eight estimators compatible with either the ΛCDM or the Dipolar model. Focus on these codes, the first step is to generate random harmonics coefficients a_lm , starting from a Best Fit model of Planck. To do this we use some routines of HEALpix (Hierarchical Equal Area isoLatitude Pixelization of a sphere), this is a software package for maps projection, pixelization, synthesis, analysis, hierarchical indexation and visualization of data on a 2D-sphere. The second step consists in inserting the found coefficients into the Copi’s code, that is an algorithm that gives in output the multipole vectors starting from the a_lm values. At this point the code provides the area vectors and consequently the value of estimators. In addition to those, I have developed another code used to analyze the observed data, and to evaluate the significance of the anomaly for different maps. This code extracts from an input map the a_lm coefficients and provides a single value of the estimator for each map. The value of the estimator is compared with the MC simulation data in order to find the rate of observed values. One of the problem is that the value of the estimator and of the MC simulation are in two different frame, the first is in the observer frame and the second one is in the CMB rest frame. In order to compare these objects they should be in the same reference system and to do this I chose to pass the observed data (observer frame) into the CMB rest frame through the de-boosting. The de-boosting process passes the a_lm extracted from the CMB maps to the new a_lm in the CMB rest frame, in this way I eliminated the relative motion of our galaxy with respect to the CMB rest frame: The results can be summarized as follows: - All analyzed quadrupole-octupole estimators (S, T, S23, T23, S 23,T 23) show an evidence of an anomalous alignment between the quadrupole and octupole at the level of ∼ 99 % (up to ∼ 99.8 %) in each analysed map; - The dipole, quadrupole and octupole are unlikely aligned at the level of ∼ 99.9 %; - WMAP and Planck data agree very well on the anomalous cases, even if the origin of these alignment is still unclear. This seems to exclude that the origin of the anomalies is connected to an instrumental systematic error; - The dipolar model does not provide a fit to data better than ΛCDM model.

• 12:50 - 13:15 Silvia Manconi (University and INFN of Torino)
  "Anisotropies in the flux of cosmic ray electrons and positrons"

  High energy cosmic ray electrons and positrons probe the local properties of our Galaxy. In fact, regardless of the production mechanism, electromagnetic energy losses limit the typical propagation scale of GeV-TeV electrons and positrons to a few kpc. In the diffusion model, the presence of nearby and dominant sources may produce an observable dipole anisotropy in the cosmic ray fluxes. This observable is crucial to discern the physical origin of the observed electron and positron fluxes. I will present a detailed study on the role of anisotropies from nearby sources in the interpretation of present cosmic ray electron and positrons fluxes. Predictions for the dipole anisotropy from known astrophysical sources as supernova remnants and pulsars of the Green and ATNF catalogs will be shown. In particular, I will discuss anisotropies for single sources as well as for a distribution of catalog sources. The results [1] will be compared with current anisotropy upper limits from the Fermi-LAT, AMS-02 and PAMELA experiments. [1]S.Manconi, M.Di Mauro, F.Donato, in preparation.

MATTER PHYSICS (1) (chair: Lapo Lolli)

• 14:20 - 14:45 Ekaterine Dadiani (Physics Department, Javakhishvili Tbilisi State University, GEORGIA)
  "Hydrophobic Droplets"

  We consider the problem of small drops’ oscillation on a vibrating surface of the same liquid under certain conditions. This phenomenon is observed because compressed air layer between two surfaces gives enough pressure to lift the drop. For some parameters drop starts bouncing and therefore air film is periodically renewed which leads to long time oscillations without coalescence. Force induced from compressed air layer is found theoretically according to Reynold’s lubrication theory. Droplet’s Lifespan dependence on relevant parameters (such as surface tension, viscosity, droplet’s radius, oscillation frequency) is examined both theoretically and experimentally and they give a good agreement with each other. So the main peculiarity of this problem is the explanation and investigation of non-coalescence of the same liquids on a vibrating surface, but there are interesting phenomena which are also worth to examine. For example if we inject more fluid into oscillating drop and increase its size considerably, it will submerge into the vibrating liquid and may last few seconds or minutes without coalescence even if the surface stops oscillations. In this case as air starts to flow out from the sides of the droplet, the thickness of air layer between the droplet and liquid surface decreases and when surfaces approach each other enough for the Van der Waals forces to activate, the drop coalesces with the liquid. The time needed for this to occur is found theoretically and is compared to experiments for different parameters. Another effect is observed when there are two or more drops on the vibrating surfaces, for different conditions they may attract or repulse each other that we explain by minimizing of surface energy and theoretical assumptions are in good agreement with experiments.

• 14:45 - 15:10 Federico Ferrarese Lupi (INRIM)
  "Self-assembly Nanofabrication techniques for Metrology"

  The miniaturization process that is currently involving several different nanotechnology research fields requires a further implementation of reliable standards and characterization techniques for the measure of the lateral length of structures having minimum features size at sub-10 nm level. Many calibration laboratories and industry need lateral length standards at the nanometric level in order to certify the resolution of a variety of measuring instruments, such as the Scanning Probe Microscopes (SPM), the Optical Phase Shift Microscopes, and the Scanning Electron Microscopes (SEM). The implementation of traceable measurement capabilities in surface analysis, material science and biophysics requires the introduction of new types of reference samples for length metrology at the nanoscale. In particular the metrological community is focusing their effort in the definition a new paradigm necessary for the realisation of nanometric lateral length standards. This goal should be achieved by possibly employing invariants of nature, like self-organized structures at the nanoscale. In this context one interesting solution in order to satisfy this lack is represented by the directed self-assembly (DSA) of Block Copolymers (BCPs) and Nanospheres (NS) inside gratings of multiple trenches. In this work we demonstrate how a careful tuning of the characteristic dimensions of the nano-domains confined (i.e. diameter and centre-to-centre distance) inside periodic gratings allows envisioning a strategy to use the DSA of DBCs as a tool for the fabrication of lateral length standards. The BCPs are a particular class of macromolecules that attracted a wide interest in the last decades due to their ability to self-assemble (SA) into well-ordered nanometric size structures. In view of the realization of a lateral length standard in our previous works, we studied incidence of the thickness films on nanometric structure orientation and morphology, when confined inside densely packed and nanometer wide trenches. A Rapid Thermal Processing (RTP) machine has been used in order to promote the SA process of cylinder-forming PS-b-PMMA BCPs having different molecular weight, as a function of the annealing parameters. With this method we managed to fabricate, in a relatively short amount of time, hexagonally packed cylindrical structures with different diameters ranging between 13 and 22 nm and center-to-center distance L0 from 28 to 47 nm. When the BCP film is heated up over the glass transition temperature, the mobility of the polymeric film increases and the capillarity forces allow the macromolecules to flow from the mesa into the trenches. As a consequence of this process, the resultant film thickness distribution is not the same inside all the trenches, but is minimum in the central trenches and increases progressively toward the periphery of the periodic structure. The results of such study have been compared with that obtained on the flat surfaces with the same BCPs. The ordering dynamic of the RTP treated BCP deposited inside the trenches showed some peculiar behaviors such as an irreversible flipping of the cylindrical The same fabrication technique can be also applied to other metrological fields, for the practical realization of fundamental units of the SI such as the Candela and the Ampère.

• 15:10 - 15:35 Ali Nasseri (ISI Foundation)
  "Effect of Manipulating Magnetic Material Properties on Magnetic Domain Wall Motion"

  Manipulating domain walls within nanostructures has many applications in the development of spintronic logic and storage devices. Such applications have led to increased interest within the scientific community in developing models which can qualitatively or quantitatively describe the domain wall motion under applied fields and currents. In this presentation, we use micromagnetic simulations and analytical descriptions of domain wall motion to showcase the effect of manipulating material properties on magnetic domain wall motion. Analytical models are presented as a simple tool to predict the effect of material engineering on DW motion before the preparation of samples, helping guide the material engineer in preparing samples with acceptable properties. The accuracy of predictions from these analytical models is compared to micromagnetic simulations in order to assess the limitations of such an approach in material engineering.

• 15:35 - 16:00 Erik Piatti (Polytechnic University of Turin)
  "Electrochemical gating in thin film superconductors: control of bulk superconductivity via surface-bound electric fields"

  The electrochemical gating technique used to realize electric-double-layer field-effect (EDL-FET) devices for the study of the fundamental physics of electronic transport in various materials is becoming increasingly popular. This is related to the unique possibility of this technique to induce huge, defect-free, purely electrostatic, surface charge densities n_2D in excess of 10^14 cm^(−2) . This large modification of the n_2D can even induce superconductivity in insulating or semiconducting materials, and was recently employed for demonstrating the true 2D nature of superconductivity in gated MoS2. Starting from our experience in EDL gating of metallic thin films of Au, where n_2D up to more than 4x10^15 cm^(−2) and reversible variations of the resistance up to about 10% at 4 K have been observed, we applied the same technique in thin films of superconductors, both conventional and unconventional. In NbN thin films with thickness d between 10 and 40 nm small positive and negative shifts in the critical temperature (|dTc| < 0.1 K) have been observed at the change of gate-voltage polarity. The Tc shift increases at the decrease of the film thickness t. All these findings indicate that the perturbation to the superconducting properties extends in a region much larger than a single unit cell. Indeed, the dependence of dTc on n2D and t can be explained by means of ab-initio DFT and strong-coupling Eliashberg calculations, only if the thin surface layer where electron accumulation takes place is coupled to the underlying, unperturbed bulk via proximity effect. Moreover, the thickness of this surface layer (i.e. the penetration length of the electric field) strongly increases for n_2D > 7-8x10^14 cm^(−2), reaching values of the order of 3 nm at the highest doping. This proximity-effect-induced transformation of the quasi-2D perturbation to the electron density into a 3D bulk modification of the superconducting properties seems to be a general behaviour in gated superconductors that could hinder the possibility to obtain large Tc shifts in thin film.

INVITED TALK

• 16:00 - 16:25 Find your Doctor (www.findyourdoc.org)
  "What meaning for a PhD nowadays? Knowledge workers as a drive for change"

  In a time when perspective of a long term career in academia are slim for the majority of Phd graduates, the very experience of the doctorate is often questioned in its meaning and worthiness by institutions and by the students themselves, partly based on assumptions that are not entirely supported by existing statistical data. We will discuss the meaning of a PhD today, getting ideas from the available statistics on the employment situation for the category, which indicate higher occupation rates and higher salaries for Doctors on the job market compared to other graduates. We will consider possible reasons for these results, which we believe are due to transversal skills acquired during research training that are extremely valuable in non-academic contexts as well, and applicable to many problems different than pure research. We will expand on the importance of transferring such skills as well as “vertical” knowledge to a business world that is in need for innovation, and mostly for a change of pace with respect to past methods and approaches. We reason on the difficulties that are involved in bridging the two worlds of PhDs and industry, presenting what Find your Doctor is doing about it at the present time and what it is planning to do in partnership with IPN.

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ASTROPHYSICS & COSMOLOGY (2) (chair: Alessio Avella)

• 9:00 - 9:25 Eloisa Menegoni (Luth, Observatoire de Paris)
  "Constraints on a scale-dependent bias from galaxy clustering"

  We forecast the future constraints on scale-dependent parametrizations of galaxy bias and their impact on the estimate of cosmological parameters from the power spectrum of galaxies measured in a spectroscopic redshift survey. For the latter we assume a wide survey at relatively large redshifts, similar to the planned Euclid survey, as baseline for future experiments. To assess the impact of the bias we perform a Fisher matrix analysis and we adopt two different parametrizations of scale- dependent bias. In our analysis we have obtained two main results. First of all, allowing for a scale-dependent bias does not significantly increase the errors on the other cosmological parameters apart from the rms amplitude of density fluctuations, σ8, and the growth index γ, whose uncertainties increase by a factor up to two, depending on the bias model adopted. Second, we find that the accuracy in the linear bias parameter b0 can be estimated to within 1-2% at various redshifts regardless of the fiducial model. The non-linear bias parameters have significantly large errors that depend on the model adopted. Despite of this, in the more realistic scenarios departures from the simple linear bias prescription can be detected with a ∼ 2 σ significance at each redshift explored.

• 9:25 - 9:50 Lichen Liang (University of Zurich)
  "The growth and enrichment of intra-group medium"

  The observable properties of galaxy groups, and especially the thermal and chemical properties of the intragroup medium (IGrM), provide important constraints on the different feedback processes associated with massive galaxy formation and evolution. In this talk, I will present a detailed analysis of the global properties of simulated galaxy groups with X-ray temperatures in the range 0.5-2 keV over the redshift range z=0-3. The groups are drawn from a cosmological simulation that includes a well-constrained prescription for galactic outflows powered by stars and supernovae, but no AGN feedback. The aims of this work are (a) to establish a baseline against which we will compare future models; (b) to identify model successes that are genuinely due to stellar/supernovae-powered outflows; and (c) to pinpoint features that not only signal the need for AGN feedback but also constrain the nature of this feedback. We find that even without AGN feedback, our simulation successfully reproduces the observed present-day group global IGrM properties such as the hot gas mass fraction, the various X-ray luminosity-temperature-entropy scaling relations, as well as the mass-weighted and emission-weighted IGrM iron and silicon abundance versus group X-ray temperature trends, for all but the most massive groups. We also show that these trends evolve self-similarly for z<1, in agreement with the observations. Contrary to expectations, we do not see any evidence of the IGrM undergoing catastrophic cooling. And yet, the z = 0 group stellar mass is a factor of 2 too high. Probing further, we find that the latter is due to the build-up of cold gas in the massive galaxies before they are incorporated inside groups. This, in turn, indicates that other feedback mechanisms must activate in real galaxies as soon as their stellar mass grows to M_star = a few 1e10 M_sun. We show that these must be powerful enough to expel a significant fraction of the halo gas component from the galactic halos. Gentle “maintenance-mode” AGN feedback, as has been suggested to occur in galaxy clusters, will not do; it cannot bring the stellar and the baryonic fractions into agreement with the observations at the same time. Just as importantly, we find that stellar/supernovae-powered winds are vital for explaining the metal abundances in the IGrM, and these results ought to be relatively insensitive to the addition of AGN feedback

• 9:50 - 10:15 Francesca Loi (University of Cagliari & INAF-Astronomical Observatory of Cagliari)
  "Magnetic Fields in Galaxy Clusters in the SKA era"

  Over the past decades, a growing number of radio halos have been discovered in galaxy clusters. These are diffuse, low-surface brightness ( 1-0.1 microJy arsec^{-2} at 1.4 GHz) and steep-spectrum ( alpha>1, S_nu propto nu^{-alpha}) synchrotron sources with no obvious optical counterparts and typical dimension of 1 Mpc. They provide an irrefutable proof of the presence of a non-thermal component in the Intracluster Medium (ICM), made by a relativistic particle population and a magnetic field spread all over the cluster volume. By now, many theories have been proposed to explain the characteristics of the non-thermal component in clusters and first of all its origin. Nevertheless these questions are still open and only a new generation of radio telescopes could help to shed light on the magnetic field nature. In this context numerical simulations are the ideal tools to provide new hints to constrain magnetic fields in galaxy clusters. During my talk, starting from state-of-art numerical simulations, I will explain how the performances of the Square Kilometre Array (SKA) will revolutionise cosmological magnetic field studies.

• 10:15-10:40 Camilo Delgado-Correal (University of Ferrara)
  "Spectroscopic identification of high redshift lensed galaxies"

  The epoch of reionization marks a major phase transition of the Universe, during which the intergalactic space became transparent to UV photons. Determining when this occurred, the physical processes involved and the sources of ionizing radiation represents one of the major goals in observational cosmology. Irrespective of the nature of this radiation, the general consensus is that the faint sources dominate the ionizing background. Searching for low luminosities (i.e. L $<$ L*, which corresponds to $m_{1500} > 27.1$ at $z = 3$) high redshift galaxies, thus complementing blank field studies, is a primary goal of surveys carried out through lensing clusters. The collaboration CLASH-VLT, has recently produced high precision lensing models of CLASH clusters, thanks to the redshift measurement of many multiply lensed systems from the CLASH-VLT spectroscopic campaign, which are critical for strong lensing mass reconstruction techniques. This effort has complemented photometric redshift information readily available from the multi-band HST survey (524 HST orbits of Hubble with more 1000 hours observations of 25 clusters in 16 filters from the CLASH program). CLASH-VLT has used the VIMOS wide-field spectrograph to obtain $ \sim 30,000$ redshifts in 12 CLASH Clusters at $z$ $= 0.2 - 0.6$ in the south, with the spectroscopic identification of $500 - 1000$ members per cluster. As a result of CLASH-VLT lensing models, accurate magnification maps can be used to derived intrinsic (unlensed) properties of lensed galaxies as faint as M$\sim$$-$15, i.e. $\sim 5$ mag fainter than M* at high redshifts. In this talk we will show some highlights of the CLASH-VLT project and the new identification of faint lyman- $\alpha$ emitters at $3.2 < z < 6.3$, by particularly exploiting Integral Field Spectroscopy of the cluster cores with VLT/MUSE.

INVITED TALK

• 10:40 - 11:10 Fabio Sciarrino (Sapienza University of Rome)
  "Quantum information on a chip"

GEOPHYSICS (chair: Emanuela Pusceddu)

• 11:30 - 11:55 Alessandro Ursi (INAF - IAPS, Rome)
  "Detection of Terrestrial Gamma-ray Flashes by the AGILE satellite"

  Terrestrial Gamma-ray Flashes (TGFs) [Fishman et al., 1994] are brief submillisecond gamma-ray emissions, produced during thunderstorms and strictly correlated to lightning and atmospheric electric activity. Serendipitously discovered in 1994 by the Compton Gamma-Ray Observatory (CGRO), these elusive events have been further investigated by several missions and satellites devoted to high-energy astrophysics, such as the Reuven Ramaty High-Energy Spectroscopic Imager (RHESSI), the Astrorivelatore Gamma ad Immagini LEggero (AGILE) and the Fermi space telescope. TGFs are thought to be bremsstrahlung gamma-rays, produced at the top of thunderclouds by avalanches of electrons accelerated within thunderstorm strong electric fields and abruptly braked in the atmosphere. Exhibiting energies ranging from few keV up to several tens of MeV, TGFs are the most energetic phenomenon naturally occurring on the Earth and they can represent a severe risk for airplanes and aircraft transports, both for the crew and the onboard electronics, that should be carefully investigated and understood. The AGILE satellite [Tavani et al., 2008] is an entirely Italian mission of the Italian Space Agency (ASI), with participation of numerous other institutes and industrial partners. Launched in 2007 and still operational, AGILE is aimed at investigating gamma-ray emissions from cosmic sources, such as compact objects, galactic molecular clouds, Active Galactic Nuclei (AGN), extragalactic massive black holes and exploding massive stars producing Gamma-Ray Bursts (GRBs). In 2012, AGILE was awarded the Bruno Rossi Prize for high-energy astrophysics, for the discovery of the variability of the Crab Nebula in gamma-rays [Tavani et al., 2011]. The wide energy range and the unique submillisecond trigger logic of its MiniCALorimeter (MCAL), together with the narrow quasi-equatorial orbit of the spacecraft, make AGILE a very suitable instrument to detect and investigate TGFs [Marisaldi et al., 2010a; Tavani et al., 2011; Marisaldi et al., 2014]. Recent improvements rose up the TGF detection rate and lead to the observation, for the first time, of multiple events occurring within single thunderstorm processes. In this talk I will address the main features of TGFs and review the observational status of this intriguing phenomenon, in the light of the recent discoveries carried out in this field by the AGILE satellite.

• 11:55 - 12:20 Alessia Nicosia (CNR-ISAC, Universities of Ferrara and Clermont-Ferrand)
  "Heterogeneous Nucleation of Ice in the Atmosphere"

  Atmospheric ice formation occurs mainly from heterogeneous freezing mechanisms. These mechanisms are predominant -with respect to homogeneous freezing- since they require lower ice-saturation ratios and higher temperature (Pruppacher and Klett, 1980). Heterogeneous ice nucleation is triggered by specific aerosol particles, named ice nuclei particles (INPs) through four thermodynamic processes: deposition, condensation-freezing, contact-freezing and immersion-freezing. The understanding of these processes and their parameterizations, are essential to predict the behaviour of clouds and their interaction with aerosol particles, and has a direct impact on global climate models and weathering predictions. Studies of central importance, in these regards, are investigations of the concentration and composition of INPs. Past studies of INP compositions have identified clay particles and mineral dusts (from Asian and Saharian deserts) as important atmospheric INP sources. Recent studies have underlined also the significance of anthropogenic aerosol contributions, like black carbon. New data are needed to clarify the significance of biogenic aerosols (as pollens, bacteria, cellulose) and marine aerosol contributions. However, the small number concentration of INPs in the atmosphere renders difficult their analysis. In addition, no existing ice nucleus measuring system is capable of detecting ice formation by all known mechanisms. The experimental methodology applied in this study is based on a Dynamic Filter Processing Chamber (DFPC), described in Santachiara et al., 2010. The DFPC is based on a “filter processing” off-line technique. By varying the different temperatures inside the chamber and the vapour supersaturation with respect to liquid and/or ice, it is possible to activate the INPs both in the deposition and in the condensation-freezing modes. Finally, the INPs concentration can be derived from the number of crystals grown on the filter and the initial sampling conditions (the volume of sampled air and/or the concentration measured by an optical counter). References: Santachiara G. et al., 2010. Atmos. Res. 96, 266-27

• 12:20- 12:45 Davide Putero (CNR - ISAC)
  "STEFLUX, a tool for investigating stratospheric intrusions"

  Stratosphere-to-Troposphere Exchange (STE) is one of the natural processes that have substantial impacts on atmospheric chemistry, and is an important aspect of climate change. In particular, stratospheric intrusions (SI) are a topic of ongoing research, especially because of their ability to change the oxidation capacity of the troposphere and their contribution to tropospheric ozone levels. Here, a novel tool called STEFLUX is presented, discussed and used to provide a first long-term investigation of SI over two global hot-spot regions for climate change and air pollution: the southern Himalayas and the central Mediterranean basin. The main purpose of STEFLUX is to obtain a fast-computing and reliable identification of the SI occurring at a specific location and during a specified time window. It relies on the trajectories computed from a STE climatology, which makes use of the ERA-Interim reanalysis dataset from the ECMWF. STEFLUX results are hereby compared to the SI observations (SIO) at two high-mountain WMO/GAW global stations in these climate hot-spots, i.e., the Nepal Climate Observatory-Pyramid (NCO-P, 5079 m a.s.l.) and Mt. Cimone (2165 m a.s.l.), which are often affected by SI events. Compared to the observational datasets at the two specific measurement sites, STEFLUX is able to detect SI on a regional scale. Furthermore, it has the advantage of retaining additional information concerning the pathway of stratospheric-affected air-masses, such as the location of tropopause crossing and other meteorological parameters along the trajectories. However, STEFLUX neglects mixing and dilution that air-masses undergo along their transport within the troposphere. Therefore, the regional-scale STEFLUX events cannot be expected to perfectly reproduce the point measurements at NCO-P and Mt. Cimone, which are also affected by small-scale (orographic) circulations. Still, the SI seasonal variability according to SIO and STEFLUX agree fairly well. Moreover, by exploiting the fact that the ERA-Interim reanalysis extends back to 1979, the long-term climatology of SI at NCO-P and Mt. Cimone is also assessed. The analysis of the 35-year record at both stations denies the existence of any significant trend in the SI frequency, except for winter seasons at NCO-P. Also, for the first time, by using the STEFLUX outputs, we investigate the potential impact of specific climate factors (i.e. ENSO, QBO and solar activity) on SI frequency variability over the Mediterranean basin and the Himalayas.

INVITED TALK

• 12:45 - 13:15 Elisa Palazzi (Institute of Atmospheric Sciences and Climate-National Research Council; ISAC-CNR)
  "Climatic changes in the mountains"

  Cryospheric components of the climate system have been affected more than others by global warming. There is growing evidence, in fact, that the rate of warming is amplified with elevation: high mountains are experiencing more rapid changes in temperature than adjacent regions or compared to the global mean. This elevation-dependent warming (EDW) represents one of the most remarkable expressions of global warming at the regional level. EDW can have serious impacts on mountain ecosystems and lead to changes in glacier dynamics, hydrological regimes, water availability and thus to negative consequences downstream. As global temperatures are projected to rise, mountain regions will likely continue being affected, since most of the feedbacks in the cryosphere-climate system operate as a warming amplifier. We present an EDW study in the Tibetan Plateau-Himalayas, one of the regions showing the most striking evidence of EDW in the observations, using global climate models (GCMs) from the CMIP5 project. The models reproduce EDW in the 20th century and show an amplification of the phenomenon by the end of the 21 st century in future projections. They are also used to investigate the mechanisms driving EDW: the change in surface albedo, associated with the absence/presence of snow at ground and with the related ice-albedo feedback, is the leading driver of EDW in the Tibetan Plateau-Himalayas, followed by the change in atmospheric humidity and downward longwave radiation. We put these results in a wider context analyzing concurrent changes in other components of the hydrological cycle, in particular precipitation and snow. For example, we found that this area will undergo a significant reduction of snow depth over the westernmost part (Karakoram) and an even stronger one (up to the 50% of the historical value) in the Himalayas, where precipitation will tend to undergo a transition toward more episodic and intense monsoonal precipitation.

BIOPHYSICS & MEDICAL PHYSICS (chair: Enrico Simonetto)

• 14:45 - 15:10 Enrico Catalano (University of Bari)
  "Characterization of physicochemical and colloidal properties of iron oxide nanoparticles and calcium-doped core-shell NPs for biomedical applications"

  Introduction Superparamagnetic iron oxide nanoparticles (SPIONs) have recently been investigated for biological applications with promising results, owing to their ability to be targeted and heated by magnetic fields. Silica and calcium-doped core-shell are very suitable coating material for SPIONs, facilitating the loading of targeting moieties and drug delivery [1]. The opportunity to incorporate calcium ions in the silica shell was considered in order to tailor the reactivity of the shell [2]. This work focuses on the recent development and various strategies in preparation, structure, and magnetic properties of naked and surface functionalized iron oxide NPs and their corresponding application. In order to implement the practical application, the particles must have combined properties of high magnetic saturation, stability, biocompatibility, and interactive functions at the surface. Materials and methods Magnetite nanoparticles have been prepared by co-precipitation method [3]. An amorphous silica shell was obtained by wet chemistry on the magnetic nanoparticles core. The addition of calcium ions in the silica shell to obtain silica-based amorphous shells was investigated to modulate the reactivity of the external surface of particles. Differently from the conventional sol-gel synthesis of bioactive glasses, that use calcium nitrate as Ca-ions precursor, calcium citrate (Sigma Aldrich) was employed in the present research work, in order to overcome the need of a high temperature thermal treatment [4]. The MNPs were characterized with SAED patterns, XRD, TEM, FESEM and DSC-TGA. The heating ability of magnetic nanoparticles in a magnetic field was investigated by the measurement of temperature variations upon exposition to an alternating magnetic field in a magnetic induction furnace (Egma 6, Felmi S.r.l, Genova, Italy). In addition nanoparticles were characterized by Magnetic Force Microscopy (AFM/MFM) to detect magnetic domains from a close distance, which can provide the magnetic force gradient image of the scanned samples [5]. The colloidal stability of these magnetic nanoparticles was determined by measuring Zeta potential (Zeta Meter device) which indicates the degree of repulsion between adjacent, similarly charged nanoparticles in a dispersion. Results and discussion Spherical magnetite nanoparticles of about 15-20 nm in diameter were obtained by the co-precipitation method. Stable suspensions in aqueous media were obtained by citric acid treatment. The addition of silica precursor (TEOS) in the synthesis medium allowed to obtain a thin and amorphous silica shell around the particles. The magnetic hysteresis curves showed that all magnetic nanoparticles exhibited a superparamagnetic behavior. The SAED patterns of magnetic nanoparticles evidence the presence of crystallographic signals compatible with magnetite and maghemite ones. The heating ability of synthesized magnetic nanoparticles was evaluate and as it was observed that Specific Absorption Rate (SAR) increased by increasing the applied magnetic field. The measurements of zeta potential of magnetic nanoparticles revealed a good colloidal stability and behavior. All synthesized nanoparticles show a good stability at neutral and basic pH values, since they show a zeta-potential between 30 and 50 mV. Magnetic revelations with AFM/MFM determined good properties of magnetic attractive forces and magnetic dipole-dipole interaction for iron-oxide nanoparticles. Conclusions The measurements of zeta potential and the physicochemical and magnetic characterization of iron-oxide nanoparticles with AFM/MFM are useful for possible applications using magnetic properties of nanomaterials, such as magnetic resonance imaging, hyperthermia, and magnetic field directed drug delivery. Understanding the relationship between the physicochemical properties of MNP constructs and their behavior will induce full translational potential of these nanoparticles [6]. The magnetic nanoparticles could be in future one of the field with higher perspectives of development for different scientific applications, especially such as a smart targeted drug delivery platform for in vivo disease therapies. REFERENCES 1. Laurent, S.; Forge, D.; Port, M.; Roch, A.; Robic, C.; Elst, L. V.; Muller, R. N. Chem. Rev. 2008, 108, 2064. 2. Bobo Yu, Claudia A. Turdean-Ionescu, Richard A. et al. Langmuir. 2012 Dec 18;28(50):17465-76 3. Z. Li et al., Mat Sci Eng C 2010, 30: 990-996. 4. Y-H Deng, C-C Wang, J-H Hu, W-L Yang, S-K Fu, Colloids and surfaces A: Physiochem Eng Aspects 262 (2005) 87-93. 5. Schreiber S, Savla M, Pelekhov DV, Iscru DF et al. Small. 2008 Feb;4(2):270-8. 6. NM Nor, KA Razak, SC Tan, R Noordin, Journal of Alloys and Compounds 538 (2012) 100-106.

• 15:10 - 15:35 Valentina Elettra Bellinzona (University of Pavia)
  "Development and Implementation of a non Gaussian model for the lateral dose prediction in a proton therapy treatment planning system ."

  Challenging issues in Treatment Planning System for hadrontherapy are the accurate calculation of dose distribution, the reduction in memory space required to store the dose kernel of individual pencil beams and the shortening of computation time for dose optimization and calculation. In this framework, the prediction of lateral dose distributions is a topic of great interest [1] because currently, a Double Gaussian parametrization [2] is typically used as approximation although other parameterizations are also available [3]. The best accuracy for this kind of calculations can be obtained by Monte Carlo (MC) methods [4], at the expense of a long computing time. This work aims to present a flexible computational model for the calculation of the lateral profile of a pencil proton beam and the results of its implementation in a Treatment Planning System (TPS). The model calculation are compared against the currently used Double Gaussian Approximation (DGA) [5], [6] and the Monte Carlo (MC) calculations. The rationale is to calculate the lateral dose distribution with the same accuracy of the MC methods, but with faster computing time. The model [7] is based on the Moliere [8] theory and provides a fully analytical description of the electromagnetic interactions; nuclear contributions are also taken into account with a dedicated parametrization. The model is reliable for any particles, any depths and for every kind of media and mixture, since energy loss effects by the primary process are fully taken into account. So far the model has being validated with both MC simulations and experimental data from Heidelberg Ion­Beam Therapy Center (HIT) in water.

• 15:35 - 16:00 Alberto Traverso (DISAT Polytechnic University of Turin, Turin Section of INFN)
  "Development and applications in clinical practice of Computer-aided Diagnosis systems for the early detection of lung cancer: state-of-art and challenges"

  Lung cancer represents one of the main public health issues and the first cause of cancer-related deaths in developed countries. Most of lung cancers are diagnosed in the last-stage, when the survival rate is very low if compared to the early-stage of the disease. Big technological effort has been put to improve the early diagnosis of lung cancer. Screening high risk population with low- dose Computed Tomography (CT) has been shown to reduce cancer mortality. These improvements have brought with them lots of clinical challenges. One of the biggest is that radiologists have to deal with a high number of images to be analyzed as faster as possible (recently referred as 'data explosion'). This big issue has motivated a very deep and heterogeneous research community to develop algorithms to support radiologists in the detection. These algorithms were given the name of Computer-aided Diagnosis (CAD) systems. Despite proved benefits, we are far from a daily usage of these systems in clinical practice. In my contribution I will discuss the technical challenges underlying this problem. In addition I will present possible solutions to tackle previous issues, with a special focus on results achieved during my PhD project, including recent results of the international medical challenge (https://grand-challenge.org/site/luna16/) we organized aiming at a large-scale validation of state-of-art CAD systems. Finally I will discuss preliminary results of the on going clinical validation of the Web- and Cloud-based CAD system developed during my research project.

• 16:00 - 16:25 Veronica Ferrero (University of Turin)
  "The INSIDE project: on-line monitoring and simulation validation with the in-beam PET scanner"

  The quality assurance of particle therapy treatment is a fundamental issue that can be addressed by developing reliable monitoring techniques and indicators of the treatment plan accuracy. Monitoring by means of PET systems is the only in-vivo non invasive technique employed clinically and has been carried out in particle therapy since 1997. However, the large radiation background produced during the irradiation highly influences the 3D spatial distribution of the beta+ emitter isotopes, so that in-beam PET monitoring is mainly performed after irradiation, resulting in a large fraction of discarded PET data. In 2013 the INSIDE (INnovative SolutIons for DosimEtry in hadrontherapy) collaboration has proposed an innovative bi-modal imaging concept that combines an in-beam PET scanner with a tracking system for charged particle imaging. The in-beam PET scanner has recently been installed at the Italian National Center of Oncologic Hadrontherapy (CNAO) in Pavia, Italy, while the tracking system is under construction. The PET system features two planar heads based on pixelated LFS scintillating crystals coupled to SiPM arrays and readout by a fast custom-designed electronic that allows on-line reconstruction from separated in-spill and inter-spill data sets. The first tests have been carried out on PMMA and antropomorphic phantoms with proton and carbon beams, showing the capability of the in-beam PET to operate during the irradiation delivery and to reconstruct the beam-induced activity map in real time. Dedicated simulations were implemented in FLUKA accounting for the detector geometry and performances and the beam delivery informations and compared to the acquired data. The reconstructed activity profiles along the beam axis show an agreement between the data and simulation distal fall-off position (corresponding to the Bragg Peak depth) within 1 mm for therapeutical doses. The system will be further characterized to evaluate its overall uncertainty and to obtain a reliable compliance index between experimental and simulated images in order to start testing with patients at CNAO.

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MATTER PHYSICS (2) (chair: Raffaella Romeo)

• 10:00 - 10:25 Luisa Mandrile (MS Industrial Chemistry)
  "Surface Enhanced Raman Scattering: exploiting plasmonic’s physic for chemical sensing"

  Surface Enhanced Raman Scattering (SERS) is a Raman Spectroscopy based technique that provides greatly enhanced Raman signal from molecules that have been adsorbed onto a proper plasmonically active metal surface [1, 2]. The overall enhancement of SERS is due to the combination of an electromagnetic enhancement mechanism (EME) and a chemical enhancement effect (CE). The first is a direct consequence of the roughness of a metal surface at the nanoscale, whereas the second is provided by a charge transfer effect promoted by the chemisorption of molecules onto the SERS active surface [3]. In particular, when a laser radiation with the proper frequency invests a plasmonically active material, the free electron cloud of the nanostructured metal starts oscillating in resonance with the electromagnetic field of the laser and the energy density is locally increased producing a hot spot region. Since the intensity of the Raman scattered radiation is proportional to the square of the magnitude of the electromagnetic field incident on the analyte, the Raman signals of molecules located into the hot spot region are strongly enhanced and the sensitivity of Raman spectroscopy is hugely increased. The exploitation of the EME instead of CE, which is strongly related to a selective chemical interaction between analyte and the metal surface [4], provides the advantage of high versatility. The plasmonic activity of a surface for SERS analysis can be designed in several ways such as vapor deposition of metal particles onto the substrates, metal nanostructuration via lithography, metal deposition over polystyrene nano-spheres mask and metal colloids fabrication and deposition, which is the strategy actually exploited in this work [5]. In the last decades, SERS has become a mature spectroscopic technique and the number of applications in the chemical, material, and life sciences has rapidly increased [6]. However, many efforts in order to optimize SERS systems and to provide a good compromise between signal intensity and reproducibility are still needed. [7] In particular, SERS technology has a great potential in the detection of trace contaminants deposited on surfaces because of the high sensitivity and the high specificity it provides. The scope of the present work is to investigate the possibility of setting up stable and easy-to-use strategies for the analysis of chemicals deposited on contaminated surfaces. Even if the Raman intensity to concentration dependence is well known [8], the same thing is not obvious when enhacement factors are concerned. A deep study of the enhancement factor as a function of concentration is here provided with the aim at proposing a calibration strategy for surface contamination analysis using SERS. In this work a real case application is presented using, as a representative probe molecule, a common pesticide, such as pyrimethanil (PMT) which is a widely used antibotrytis fungicide [9]. A sensitive and rapid method to detect and quantify PMT residues on pome fruits was developed using SERS. Different types of AuNPs with different size and shape were synthetized and tested to determine the highest enhancement efficiency. Raman mapping strategy was exploited to increase signal reproducibility from spot to spot analysis and to minimize bias due to different local surface morphologies. The optimized methodology was tested on real samples providing: i) sensitive and specific in situ detection of the fungicide directly on the contaminated fruit surface; ii) a metrological tool for PMT quantification on the entire surface of pome fruits in accordance with the European law limits [10]. The method here developed is sensitive and fast; it can be applied in routine analysis for PMT detection on apples and has the potential for broad applications concerning other hazardous chemicals in food. The successful external validation tests drove to the conclusion that standardized quantitative SERS methodology can be developed and used for a wide range of applications. [1] Nie, S.; Emory, S. R., Science 1997, 275, (5303), 1102-1106. [2] Kneipp, K.; Kneipp, H.; Itzkan, I.; Dasar, R.R.; and Feld, M.S. Chem. Rev. 1999, 99, 2957-2975 [3] Weaver, M.J.; Zou, S.; Chan, H.Y.H. Anal. Chem. 2000, 72, 38A-47° [4] Lombardi, J. R.; Birke, R. L.; Lu, T.; Xu, J., The Journal of Chemical Physics 1986, 84, (8), 4174-4180 [5] Jensen, T.R.; Malinsky, M.D.; Haynes, C.L.; and Van Duyne, R.P. J. Phys. Chem. B 2000, 104, 10549 –10556 [6] S. Schlücker, Angew. Chem. Int. Ed., 2014, 53, 4756-4795. [7] Ruyan Hou, Shintaro Pang and Lili He; Ananlytical Methods (2015) DOI: 10.1039/c5ay01058f [8] L. Mandrile, A. M. Giovannozzi, F. Pennecchi, A. Saverino, C. Lobascio and A. M. Rossi, Anal. Methods, 2015,7, 2813-2821 DOI: 10.1039/C4AY02850C [9] 5. Yu C, Zhou T, Sheng K, Zeng L, Ye C, Yu T, Zheng X (2013), International Journal of Food Microbiology 164 (2-3):155-160. [10] Review of the existing maximum residue levels (MRLs) for pyrimethanil according to Article 12 of Regulation (EC) No 396/2005, EFSA Journal 2011;9(11):245

• 10:25 - 10:50 Riccardo Ragona (Ghent University - LPP-ERM/KMS)
  "ICRF Traveling Wave Antennas for fusion devices"

  Ion Cyclotron Resonance Heating and Current Drive is a method that has the ability to heat directly the ions in the Deuterium-Tritrium fuel to the high temperature needed for the fusion reaction to works and to help the Magnetohydrodynamic (MHD) stability control of steady state operation of large fusion devices. As large machine are expected, large volumes of plasma must be heated up to relevant temperatures through the injection of a large amount of auxiliary power. There are two possibilities to provide that power: via a small surface, obtaining large power densities (>10 MW/m2), or via a large surface, decreasing the power densities. While the first method is nowadays used, reducing the power density in the plasma edge could be a key factor to solve some of the problems experimentally encountered, like impurity production via Radio Frequency sheath rectification, that increase the plasma losses. The launching structures, or antennas, used in present research devices are usually made of a short series of current conductors on which a large electric current flows and creates the magnetic field that excites Fast Magnetosonic Waves in the target plasma. Then wave-particle resonance interaction transfers the power of the RF waves to the particles increasing their momentum. Absorption studies will reveal which of those waves maximize the power transfer. The capability of efficiently couple the RF power to the plasma plays a big role in the overall performance of a fusion device. A Traveling Wave Antenna (TWA) in a resonant ring configuration is a good candidate for an ICRF auxiliary Heating and CD system. It has the capability to increase the coupled power with respect to present design and to have a highly selective power spectrum that can be peaked around the maximally absorbed wave. It is also insensitive to the loading variations due to fluctuation of the plasma edge increasing the reliability and the efficiency of the system. It works as a low power density launcher due to the possible large number of current carrying elements while not impairing the functionality of the Tritium Breeding Blanket. Different options are under investigation with both numerical simulations and experimental validation to find the best configuration for a large fusion device as the DEMO reactor.

• 10:50 - 11:15 Paolo Brogi (---)
  "A digital Avalanche Pixel Sensor for charged particle detection (APiX)"

  We present the implementation and the preliminary tests of a new type of silicon sensor for position sensitive charged particle detection with internal gain (operated in Geiger-mode). The device, comprising two vertically-aligned CMOS pixel arrays, implements in-pixel circuits to perform the vertical coincidence between two simultaneous avalanche events occurring on either pixel to measure the position of the impinging particle with a strong reduction of the dark count rate. A proof-of-concept two-layered sensor was designed and fabricated with a 150 nm CMOS process and vertically integrated via micro bump bonding. The sensor includes a 48 × 16 pixel arrays with 50 μm × 75 μm pixels, with different active areas ranging from 43 × 45 to 30 × 30 μm2. The avalanche detectors have been characterized and breakdown voltage non-uniformity lower than 20 mV was measured. The median count rate of accidental coincidences on the whole sensor (~ 1 mm2) does not exceed 33 Hz at an over-voltage of 1 V. The APIX chip is mounted on a support board that supplies power and control signals and is interfaced with a control and acquisition board. In this way, two different APIX chips were mounted on top of each other on their respective support boards. This setup is now fully operative and will be tested in September 2016 at CERN-SPS with beams of high-energy electrons and protons.

PARTICLE PHYSICS (chair: Alessandro Cultrera)

• 11:35 - 12:00 Irene Nutini (Gran Sasso Science Institute (INFN))
  "The first pion-Ar cross-section measurement with the LArIAT experiment"

  A complete understanding of neutrinos properties requires a study and a characterization of the interactions of the daughter particles created in a neutrino-nucleus interaction. The Liquid Argon In A Testbeam (LArIAT) experiment is a small-scale liquid argon detector situated in the Fermilab Test Beam Facility. The LArIAT experiment is exposed to a tertiary beam comprised of mostly pions along with a mix of muons, protons, kaons, and electrons. LArIAT’s goal is to characterize the response of the LArTPC to known incoming charged particles and measure their interactions in Argon, in order to understand their cross-sections and to help developing and tuning simulations and reconstruction algorithms for LArTPC neutrino experiments. This talk presents the world’s first measurement of a pion cross-section on an Argon target, made with the LArIAT detector.

• 12:00 - 12-25 Raffaele Del Grande (LNF-INFN)
  "Investigating the low-energy K- interactions in nuclear matter with AMADEUS"

  AMADEUS is dealing with the study of the low-energy K- interactions in light nuclei. The aim is to shed light on fundamental open issues concerning the non-perturbative QCD regime in the strangeness sector, with implications going from the particle and nuclear physics to astrophysics (equation of state of Neutron Stars). AMADEUS takes advantage of the DANE collider at LNF-INFN, which provides a unique source of monochromatic low-momentum kaons. In a first stage, the KLOE detector was used as an active target in order to obtain excellent acceptance and resolution data for the products of the K- nuclear capture on H, 4He, 9Be and 12C nuclei. The strength of the K- binding in nuclei is currently under investigation through the study of the K- multi-nucleon absorption processes in Λ/Σ – p,d,t channels, and the search for anti-kaon multi-nucleon bound states. We are also inquiring into the (Σπ)0/Λπ- channels to get information on the Λ*/Σ* resonant versus non resonant transition processes and to achieve a deeper insight into the properties of the Λ(1405).

• 12:25 - 12:50 Elisa Incani (University of Cagliari and INFN)
  "Dimuon production in Pb-Pb collisions at 20-160 AGeV at the CERN SPS: Mapping the QCD phase diagram in the transition region with a new experiment"

  The theory of strong interactions, Quantum ChromoDynamics (QCD), predicts a phase transition at high temperature and/or baryon density between hadronic matter, (where quarks and gluons are confined inside hadrons) and a deconfined state of matter, the so-called quark-gluon plasma (QGP). The possible phases of strongly interacting matter can be displayed in a phase diagram as a function of its temperature and the baryon density. The QCD phase diagram is mainly studied in the region of low baryon density. In this regime, around a critical temperature of 155 MeV, the phase transition between hadronic matter and the QGP would be a cross-over. On the other hand, lattice QCD calculations for moderate temperatures and high baryon densities suggest a first order transition between hadronic matter and the QGP with coexistence of a mixed-phase, but this region is largely unknown. At the phase transition, also chiral symmetry should be restored. This implies a change in the hadron mass spectrum, but how this is realized is not known. In this talk we present new ideas to experimentally investigate these fundamental phenomena with a new fixed-target experiment at the CERN SPS (Super Proton Synchrotron) dedicated to the measurement of the production of muon pairs with unprecedented precision. The CERN SPS accelerator is ideal for such systematic investigations, because it will be able to deliver high quality intense lead beams over the energy range from 5-6 up to 17 GeV in the centre-of-mass system. Correlated dileptons provide a probe of the expanding system, since they are produced at all stages of the evolution and they also retain the primary information of the system, because of the absence of any final state interaction. Dileptons offer the possibility to measure their temperature to obtain a caloric curve, to probe chiral symmetry restoration by studying for the first time the mass modifications in a simultaneous measurement of the vector meson ρ and its axial vector partner a1, and to study of J/ψ suppression and open-charm production.

INVITED TALK

• 12:50 - 13:20 Andrea Giachero (INFN of Milano-Bicocca)
  "Assess the neutrino mass with micro and macro calorimeter approach"

  Thanks to oscillation experiments it is now an established fact that neutrinos are massive particles. Yet, the assessment of neutrinos absolute mass scale is still an outstanding challenge in particle physics and cosmology as oscillation experiments are sensitive only to the squared mass differences of the three neutrino mass eigenstates. The mass hierarchy is not the only missing piece in the puzzle. Theories of neutrino mass generation call into play Majorana neutrinos and there are experimental observations pointing toward the existence of sterile neutrinos in addition to the three weakly interacting ones. Three experimental approaches are currently pursued: an indirect neutrino mass determination via cosmological observables, the search for neutrinoless double β-decay, and a direct measurement based on the kinematics of single β or electron capture (EC) decays. Bolometers and calorimeters are low temperature detectors used in many applications, such as astrophysics, fast spectroscopy and particle physics. In particular, sensitive calorimeters play an important role in the neutrino massa measurement and in the search for the neutrinoless double beta decay. There has been great technical progress on low temperature detectors since they were proposed for neutrino physics experiments in 1984. This general detector paradigm can be implemented in devices as small as a micrometer for sub eV radiation or as large as 1kg for MeV scale particles. Today this technique offers the high energy resolution and scalability required for leading edges and competitive experiments addressing the still open questions in neutrino physics.

MATTER PHYSICS (3) (chair: Enrica Pessana)

• 14:20 - 14:45 Matteo Puviani (University of Modena and Reggio Emilia)
  "Periodically driven interacting electrons in 1D: a many-body Floquet approach"

  Under the influence of periodic fields quantum systems may reach regimes inaccessible under equilibrium conditions and new phases may be engineered by a tunable control [1]. The recent evidence of optically quenched superconductivity or the possibility to induce topological phases by light irradiation in systems that would be standard in stationary conditions are relevant examples in this field [2]. The coexistence of periodic driving forces and electron-electron correlation is particularly interesting for two main reasons: on one side, according to the Peierls' substitution, the external driving effectively modulates the inter-site hopping enhancing the effects of the e-e repulsion and the tendency to an insulating behaviour. On the other hand, irradiation itself is responsible for a photo-doping consisting in an electronic energy dressing that may turn a Mott insulator into a metal. Due to these competing effects, novel phenomena are expected when strongly correlated quantum systems are exposed to time-dependent fields. We have developed a scheme that allows to treat photo-induced phenomena in the presence of many body interactions, where both the nonlinear effects of the external field and the electron-electron correlation are treated simultaneously and in a non-perturbative way. The Floquet approach is used to include the effects of the external time-periodic field and the Cluster Perturbation Theory to describe interacting electrons in a lattice. They are merged in a Floquet-Green function method that allows to calculate photon-dressed quasiparticle excitations. The 1D Hubbard chain in static conditions is the prototype of Mott-Hubbard insulator, exhibiting at half filling an insulating behaviour, no matter how weak the e-e repulsion is. We have explored the combined effects of on-site e-e interaction and of a time-periodic field on an extended 1D lattice and we show that an unconventional Mott insulator-to-metal transition occurs for given intensities and frequencies of the applied field [3]. References: [1] Gomez-Leon, Andres, et al., “Floquet-Bloch theory and Topology in Periodically Driven Lattices”. Physical Review Letters, 110, 200403-1 200403-5, (2013) [2] Wang, Y. H., et al., “Observation of Floquet-Bloch States on the Surface of a Topological Insulator”. Science, 342, 453-457 [3] Puviani, M. and Manghi, F., “Periodically Driven Interacting Electrons in 1D: A Many-body Floquet Approach”, arXiv:1606.03889v2, submitted to PRB

• 14:45 - 15:10 Giorgi Khomeriki (Physics Department, Javakhishvili Tbilisi State University, GEORGIA)
  "Parametric resonance induced chaos in magnetic damped driven pendulum"

  A damped driven pendulum with a magnetic driving force, appearing from a solenoid, where ac current flows is considered. The solenoid acts on the magnet, which is located at the free end of the pendulum. In this system, the existence and interrelation of chaos and parametric resonance is theoretically examined. Derived analytical results are supported by numerical simulations and conducted experiments. In the present paper driving force is position angle dependent, particularly I consider a realistic example of driven damped pendulum model, via introducing magnetically driven case. In the context of magnetic pendulum, driving force is of a magnetic origin, particularly a solenoid with ac current is acting on the magnet, which plays a role of a bob in a pendulum with a rigid rod. Therefore the amplitude of a harmonic force greatly depends on the distance between solenoid and the magnet, making it angle dependent in a non-trivial form. In the frames of this model a possibility of onset of chaos has been examined analytically, numerically and experimentally. In our case (when orientation of solenoid’s dipolar moment is parallel to pendulum in unperturbed position) for some values of ac field and/or distance between solenoid and magnet chaos is observed due to the parametric resonance. Thus the main peculiarity of our model is that the existence of parametric resonance is a necessary condition for the onset of chaos in the system and in order to study chaotic behavior, Lyapunov exponents were calculated using numerical simulation and were compared to theoretical growth rate. Besides that, theory is compared to both numerical simulations and my own experiments. Paper published: G.Khomeriki, Physics Letters A Volume 380, Issues 31–32, 15 July 2016, Pages 2382–2385. doi:10.1016/j.physleta.2016.05.049 arxiv link: https://arxiv.org/abs/1511.04593 link of presentation on dropbox: https://www.dropbox.com/s/g5ie1vuam15nxcz/magnetic%20pendulum.pptx?dl=0

• 15:10 - 15:35 Stefano Marcantoni (University of Trieste)
  "Heat, work and entropy production in a bipartite quantum system"

  The phenomenological laws of classical thermodynamics effectively describe the balance of energy and entropy in macroscopic bodies, but, if the systems considered are small, say mesoscopic or microscopic, it is not evident that the same laws hold true. Moreover, below a certain size quantum effects become important and they are expected to play a significant role. Therefore, it is worth studying how the laws of thermodynamics can be stated in such a domain and, on the other hand, how the macroscopic behavior emerges from the underlying microscopic dynamics. The theory of open quantum systems has been used to tackle this issue since the seminal paper of Alicki "The quantum open system as a model of the heat engine" in 1979. If the dynamics is described by a time-dependent Lindblad generator it was shown (Alicki, Spohn, Lebowitz) that the internal entropy production rate is always non-negative. However, this is not the case if a generic non Markovian evolution is considered. Therefore, I'm interested in a formulation of the laws of thermodynamics that accounts for non Markovian effects. In particular, I'm investigating what happens if the environment has a finite size and what is the role played by correlations between system and environment. Together with my supervisor Prof. Fabio Benatti (University of Trieste) and in collaboration with the group of Prof. Ali Rezakhani (Sharif University of Technology-Tehran) I’ve considered a generic bipartite quantum system, initially prepared in a product state, and I’ve studied the energy and entropy exchange in time between the interacting subsystems [1]. By properly defining heat, work and entropy production at the microscopic level, we could write a generalized version of the first and second law of thermodynamics that highlights the role of correlations and interaction. If one of the two subsystems is taken to be a Markovian thermal bath, the known results from the theory of open quantum systems are recovered. Some interesting features of our formulation can be illustrated by a simple example, namely, a qubit undergoing dephasing due to the coupling with a bath of harmonic oscillators. This model is important because it is analytically solvable and many physical quantities are computed exactly, without the usual weak-coupling approximation. [1] S. Alipour, F. Benatti, M. Afsary, F. Bakhshinezhad, S. Marcantoni, and A. T. Rezakhani, arXiv:1606.08869[quant-ph]