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ASTROPHYSICS I (chair: F. Loi)

• 10:00 - 10:25 Isabella Paola Carucci (SISSA, Italy)
  "Using cosmic neutral hydrogen as large scale structure tracer"

  "The LCDM model experiences small scale problems that could be solved by allowing dark matter to have intrinsic thermal velocities, i.e. warm dark matter (WDM). In this talk I discuss the impact of WDM on the 21cm power spectrum, by means of high resolution hydrodynamical N-body simulations of different dark matter (DM) scenarios and different models of neutral hydrogen (HI) spatial distribution. I forecast the bounds that the Square Kilometre Array (SKA) will place on the DM particle mass.

• 10:25 - 10:50 Marco Marongiu (University of Ferrara - IRAP, Italy)
  "Prospects on short gamma-ray bursts with the forthcoming Chinese Hard X-ray Modulation Telescope"

  The Hard X-ray Modulation Telescope (HXMT) mission, scheduled to be launched in June 2017, is the first Chinese X-ray space observatory that will observe the X-ray sky in a broad energy range (2-3000 keV). Here I focus on the expected contribution of HXMT to the study of short GRBs above 100 keV, where they release most of their energy. Thanks to its large effective area (about 5000 cm^2) we will be able to constrain the spectral shape of short GRBs, in particular of the peak energy Ep of the nuF(nu) spectrum as well as the radiated energy, with unprecedented accuracy. I present the main results of a number of simulations that compare the observed spectra of short GRBs observed by the Gamma-ray Burst Monitor (GBM) aboard the Fermi satellite with the data expected by HXMT. The astrophysical relevance of short GRBs cannot be overstated: their progenitors are thought to be compact object mergers and, as such, are strong candidates for gravitational wave sources.

ASTROPHYSICS I

• 11:20 - 11:45 Arianna Miraval Zanon (University of Padova, Italy)
  "Study of the eclipse region of redback millisecond pulsar J1431-4715"

  Millisecond pulsars (MSPs) are a population of neutron stars (NSs) with fast spins (hundreds of rotations per second) and relatively weak magnetic fields (10^8 G). These objects are thought to be generated in low-mass X-ray binary systems (LMXBs) where a neutron star is spun up by the accretion of material and angular momentum from its companion. Among the MSPs, the so called "eclipsing binary millisecond pulsars" emit a radio signal which changes or completely disappears, at some particular orbital phases. In our work we focused on a sub-population of eclipsing MSPs: the so-called redback (RB) MSPs, which are considered the missing link between the LMXBs and the recycled binary radio pulsars. Observations of these systems indicate the presence of a low-dense, highly ionized gas cloud enwrapping the companion, that causes delay or complete absorption of the radio signal. We studied a RB pulsar system that was discovered with the High Time Resolution Universe Survey with the Parkes Radio Telescope. We analysed data acquired from 2011 until today in three different frequencies. After having accurately measured the rotational, astrometric and orbital parameters of our binary ("timing"), thanks to our multi-frequency observations we could also perform a study of the eclipse region. The aim of our work is oriented in the research of a mechanism to account for the periodic disappearance or attenuation of the pulsed signal. Using future optical observations we expect to put further constraints on the system geometry, intrabinary shocks and the unknown physics of pulsar winds.

• 11:45 - 12:10 Sara Loru (INAF - Cagliari, Italy)
  "Modelling spatially-resolved spectra of Supernova Remnants with the Sardinia Radio Telescope"

  Galactic Supernova Remnants (SNRs) spectra are typically featured by synchrotron radio emission arising from the relativistic electrons, and high-energy emission possibly related to both leptonic (Bremsstrahlung and Inverse Compton) and hadronic processes (pi0 mesons decay) which are a direct signature of cosmic rays acceleration. The origin of the high-energy emission is still debated. Indeed, the Bremsstrahlung and Inverse Compton bumps observed in gamma-rays are bounded to synchrotron spectral slope and cut-off in the radio domain. For this reason, it is crucial to fully constrain lepton contributions first through radio-observed parameters, in order to better assess high-energy hadronic emission and then cosmic rays production. In the framework of the Astronomical Validation and Early Science activities of the Sardinia Radio Telescope (SRT, www.srt.inaf.it), we performed observations at three frequency bands (1.6, 7 and 22 GHz) of middle-aged SNR W44 and IC443 in order to study spectral slopes and possible breaks at high-frequency. Thanks to single-dish imaging performances of SRT and to innovative imaging techniques based on On The Fly scans, we obtained for the first time SNR maps providing detailed structure of the SNRs at high-frequency. Image quality is comparable to interferometric mapping carried out with the Very Large Array at low frequencies. With the aim of studying the properties of W44 and IC443 sub-regions (related to different electron populations), we obtained spatially-resolved spectral indices maps by coupling 1.6 GHz and 7 GHz images. In perspective, the inclusion of the high-frequency (22 GHz) radio maps in the analysis will be crucial to better characterize the spatial-resolved spectra and search for possible spectral steepening or breaks in selected SNR regions, assessing the high-energy tail of the region-dependent electron distribution.

• 12:10 - 12-35 Alessandro Buzzelli (University of Rome "Tor Vergata" and University of Rome “La Sapienza”, Italy)
  "Impact of polarized foreground on LSPE-SWIPE observation"

  Measurements of Cosmic Microwave Background (CMB) temperature anisotropy and E-mode polarization allowed the establishment of a concordance cosmological model with very tight constraints on the parameters, such as the curvature, the expansion rate and the content of the Universe. The search for the CMB B-mode polarization is nowdays the new frontier of observational Cosmology. A B-mode detection could constrain important aspects of the cosmic reionization epoch and give a convincing confirmation to the existence of a primordial gravitational wave background as predicted by inflationary models. The major obstacle towards a B-mode observation is the presence of polarized foregrounds. In particular, synchrotron and thermal dust emission from the Galaxy dominate over the primordial signal at low and high frequencies, respectively. In this work we investigate the impact of polarized foregrounds in the context of forthcoming sub-orbital B-mode experiments. We focus on the baseline of the LSPE-SWIPE balloon-borne mission and forecast the effect of synchrotron and thermal dust contamination on the polarization sky-map and BB angular power spectrum reconstruction. Due to the high-frequency channels of LSPE-SWIPE (140, 220 and 240 GHz), the impact of synchrotron is sub-dominant (but not negligible). On the contrary, the amplitude of thermal dust is few orders of magnitude larger than the B-mode target sensitivity even when aggressive Galactic masks are applied. We conclude that foreground cleaning techniques able to mitigate the thermal dust contamination to at least the 1% level will be required.

• 12:35 - 13:00 Giorgio Viavattene (University of Rome "Tor Vergata", Italy)
  "Remote sensing of the solar photosphere: a tale of two methods"

  Solar spectro-polarimetry is a powerful tool to investigate the physical processes occurring in the solar atmosphere. The different states of polarization and wavelength have in fact encoded the information about the thermodynamic state of the solar plasma and the interacting magnetic field. In particular, the radiative transfer theory allows us to invert the spectro-polarimetric data to obtain the physical parameters of the different atmospheric layers and, in particular, of the photosphere. In this work, we present a comparison between two methods used to analyze spectro-polarimetric data: the classical Center of Gravity (CoG) method in the weak field approximation and an inversion code that solves numerically the radiative transfer equation. The CoG method returns reliable values for the magnetic field and for the line-of-sight velocity in those regions where the weak field approximation is valid (field strength below 200 Gauss), while the inversion code is also able to return the stratification of many physical parameters in the layers where the spectral line used for the inversion is formed.

CONDENSED MATTER PHYSICS I (chair: V. Sarritzu)

• 14:30 - 14:55 Ferdinando Insalata (Imperial College London, UK)
  "Coarsening and Percolation in a disordered ferromagnet"

  Phase ordering kinetics, the growth of order via domain coarsening after a quench from the homogeneous phase into one with broken symmetry, is a much-studied phenomenon. The most familiar example is a ferromagnet quenched to a temperature well below the critical one. The initial disordered state becomes unstable after the quench and the system evolves towards one of the two possible ordered configurations with opposite magnetizations. Relaxation toward the new equilibrium is promoted by the formation and growth (coarsening) of domains of aligned spins. Coarsening is not restricted to magnetic systems but occurs in many areas of science. Examples in condensed matter include binary alloys or liquids, polymer blends and liquid crystals. Moreover, coarsening is also involved in cosmological models, economics, social sciences etc. A standard theoretical approach to study coarsening phenomena is based on the kinetic Ising model, originally introduced by Glauber. The stochastic evolution of this model exhibits, after a short transient, the formation of a stable percolating cluster, which largely determines the later evolution and the final state of the system. After reviewing the state of the art of percolative effects in coarsening in clean systems, I will discuss the generalization to systems with structural disorder, focusing on the Random Bond and Random Field Ising Model. By means of large-scale numerical simulations, computing quantities such as the pair-connectedness function or the winding angle, for which percolation theory provides exact expressions, we show that the addition of quenched randomness does not change significantly the percolation properties. Our results prove that percolation is intimately connected to phase ordering kinetics, irrespectively of specific details such as the presence of disorder. This could represent a first step toward the generalisation of existing analytical theories for pure systems to the cases with quenched disorder.

• 14:55 - 15:20 Giuseppe Luongo (CNR-SPIN Salerno, Italy)
  "Graphene/Silicon Schottky photodiode"

  ,"The graphene/semiconductor junction is receiving increasing attention by scientists and engineers for its interesting basic physical properties and for the many potential applications. Graphene/semiconductor planar junction have been proposed as photodetectors, solar cells, chemical and biological sensors, rectifiers, etc. These junctions have the potential to eliminate the need for p-n junctions with reduced depth in modern CMOS technologies and are, therefore, of considerable interest to the semiconductor industry. We have designed, fabricated and studied two different kind of graphene/silicon devices. We have studied the electrical characteristics of a representative device at different temperatures and the response to light. The first device is obtained transferring CVD-synthesized graphene on a substrate of high doped n-Si patterned to form two-dimensional superficial arrays of nanometer-sized tips. Graphene is laid on these tips forming Schottky nano-junctions. We have found that the device behaves as Schottky diode with a rectification factor increasing with decreasing temperature and greater than 100 at room temperature. The ideality factor of this diode tends to the unit value as the temperature increases. We observed almost linear increase in the height of the Schottky barrier moving from reverse to forward voltages, with a value of 0.36 ± 0.02 eV at zero bias. The original geometry of our device favors the absorption of light by multiple reflection on the silicon tips. Furthermore, the amplification of the electric field on the apex of the tips improves the separation of photogenerated charges and provides sufficient energy to start avalanche multiplication to impact ionization. This implies an increase of up to two orders of magnitude of the integral photoresponse (3A/Wat 3mW/cm^2 of intensity) in comparison to planar junctions. The second device was fabricated by transferring CVD-synthesized graphene on low doped n-type substrate. The device achieves photoresponse as high as 3AW-1 and normalized detectivity > 3.5×1012cmHz1/2W-1 in the visible range. The device exhibits a photocurrent exceeding the forward current, as photo-generated minority carriers, accumulated at Si/SiO2 interface of the Gr/SiO2/Si capacitor, diffuse to the Gr/Si junction. We show that the same mechanism, when due to thermally generated carriers causes the increased leakage often measured in Gr/Si heterojunctions. At room temperature, we measure a zero-bias Schottky barrier height of 0.52eV, as well as an effective Richardson constant A**= 4×10-5 Acm^-2 K^-2 and an ideality factor n ≈ 3.6, explained by a thin (<1 nm) oxide layer at the Gr/Si interface. Our devices are consequently a considerable contribution towards the development of graphene/silicon heterojunctions for optoelectronic applications.

• 15:20 - 15:45 Elisa Pinna (University of Cagliari, Italy)
  "Organic-Inorganic hybrids of eumelanin and porous Si: how to improve the junction stability"

  Hybrid organic-inorganic junctions attract a growing interest for hybrid photovoltaic devices joining the low fabrication costs of the former and the high efficiency of the latter. Here we investigate a bulk heterojunction made of n+-type porous silicon (PSi) and eumelanin. This organic biomaterial has a broadband monotonic absorption in the UV-visible range that improves the pure porous silicon photovoltaic properties. In this work we address the temporal stability issues of this type of junction. In fact, significant fluctuations of the photocurrent values, as compared with other organic/inorganic hybrids, and the fast ageing of the samples (a few days lifetime) have been experienced. We tentatively attribute these fluctuations to the instability of the PSi/melanin interface and to the contraction of the melanin within the pores after the polymerization procedure. Herein we then attempt to tackle this problem by a rational approach aimed at stabilizing and improving the interface between PSi and the polymer. PSi samples have been prepared by etching n+-doped silicon wafers in a HF:H2O:EtOH. The samples have been divided in three sets. The first has been studied without any further surface modification, the second has been lightly oxidized using a KNO3 0.1 M aqueous solution and the third has been grafted with 4-nitrobenzenediazonium (NBD) to stabilize the inner surface of porous silicon. The polymerization of eumelanin inside the pores has been done in two different ways: chemically and electrochemically. For the chemical one, a 7 µL drop of monomer ethanolic solution (pure 5,6-dihydroxyindole (DHI) or a mix of DHI and DHICA (5,6-dihydroxyindole-2-carboxylic acid) depending on the case) has been put on the porous surface and distributed by spin coating; to catalyze the polymerization process, the samples have been exposed to gaseous NH3. The electrochemical polymerization was carried out by means of cyclovoltammetry in an ethanolic KNO3-saturated solution containing DHI monomer at concentration of 1mg/mL. The photocurrent from all samples has been measured both in white light and using low-pass filters by means of a Keithley 4800 multimeter. The measurements have been repeated for several weeks to monitor their evolution in time. The results show photostability differences among all the junctions analyzed. In particular, a better photocurrent stability was found for the electropolymerized samples without NBD.

• 15:45 - 16:10 Roberto Cardia (University of Cagliari, Italy)
  "Optical Absorption of Eumelanin Tetramers: a TDDFT study"

  Eumelanin is a protective biological pigment whose the exact molecular structure and the origin of its broadband absorption spectrum are still under scientific investigation. In this work we report a first-principles computational investigation on the optical properties of some tetramers which are present in literature as promising eumelanin structure candidates. In particular, we have examined potential protomolecules composed by: 5,6-dihydroxyindole (DHI), indolequinone (IQ), and its two tautomers (MQ, NQ), as monomer units assembled in different structural arrangements: porphyrin-like rings and open chain structures. For all compounds we performed all-electron ground state optimization by means of Density Functional Theory (DFT) and Time Dependent DFT (TDDFT) calculations for the evaluation of optical absorption in the range of Visible/near UV, using localized Gaussian basis-set and hybrid exchange-correlation functionals. We have studied the optical absorption spectra in different oxidation states, and in different relaxation morphologies: isolated molecule at their proper optimized geometries and at the relaxed geometries obtained after deposition on Si(1,0,0) surface. These optical spectra and the corresponding electronic transitions could be a useful tool for the researchers in order to identify the correct melanine structure.

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BIOPHYSICS (chair: M. Di Stefano)

• 9:35 - 10:00 Andrea Basciu (University of Cagliari, Italy)
  "A new protocol to improve the predictive power of molecular docking"

  Molecular recognition is the key event governing the dynamics of very specific and highly regulated processes that run cellular life. Therefore, understanding quantitatively molecular recognition events is crucial for basic research in life sciences and a prerequisite to the success of computer-aided drug design. Essential information to this goal is furnished by the atomic-level structures of the complexes formed by receptors and their ligands. Experimental methods such as X-ray crystallography, cryo-electron microscopy (cryo-EM) and nuclear magnetic resonance (NMR) structure determination have been essential in elucidating the extent and the types of conformational changes accompanying molecular recognition events involving proteins, nucleic acids and other biological macromolecules. An alternative and a complement to experimental methods is represented by molecular docking, a technique that aims to mimic ligand-receptor association in silico providing an atomistic description of the recognition event. Most docking algorithms include flexibility of the ligand and only limited flexibility of the receptor, which compromises the success of docking when the binding event is accompanied by significant structural rearrangements of the partners. An attempt to overcome this limitation is to include the flexibility of the receptor implicitly in the so-called ensemble-docking strategy, whereby a set of different conformations of the receptor (and also of the ligand in some cases) is considered. In order to be successful, structures within the ensemble should include conformations prone to host ligands (holo form). From a computational perspective, ensembles are generally extracted from cluster analysis on molecular dynamics trajectories of the receptor either in complex with ligands or unbound (apo form). However, when high barriers separate different basins of the free energy profile, standard molecular dynamics simulations are not able to efficiently sample the conformational space of the receptor. Here we present a computational protocol based on metadynamics and aiming to generate holo-like conformations of a protein starting from its apo structure, without any prior information on the complex. In order to validate our method, we chose as test systems a few proteins for which both the experimental apo and holo structure were available, and for which previous attempts to generate suitable receptor structures and native-like docking poses failed. The comparison between the conformations we obtained and the experimental structure of the complex is encouraging, in particular at the binding site where we obtained all-atom RMSD values as low as 1.3 Å. Furthermore, using the structures of the receptor obtained with our method in ensemble docking calculations gives results comparable with those obtained by using an ensemble of conformations extracted from a molecular dynamics trajectory of the complex.

• 10:00 - 10:25 Alessia Embriaco (University of Pavia - INFN, Italy)
  "MONET code for the evaluation of the dose in Hadrontherapy"

  The accurate evaluation of the dose distribution is an open issue in Hadrontherapy. MONET (Model of ioN dosE for Therapy) is a code for the computation of the 3D dose distribution for protons in water. It accounts for all the physical interactions and is divided in two part: the lateral and longitudinal distribution. For the lateral profile, MONET is based on the Molière theory of multiple Coulomb scattering. To take into account also the nuclear interactions, we add the Cauchy-Lorentz function, where the two parameters are obtained by a fit to a FLUKA simulation (Bellinzona et al., PMB 2016). We have implemented the Papoulis algorithm for the passage from the projected to a 2D lateral distribution. For the longitudinal profile, we have implemented a new calculation of the average energy loss that is in good agreement with simulations and other formulas. The inclusion of the straggling is based on the convolution of energy loss with a Gaussian function. In order to complete the longitudinal profile, also the nuclear contributions are included in the model using a linear parametrization with only two parameters. The total dose profile is calculated in a 3D mesh by evaluating at each depth the 2D lateral distributions and by scaling them at the value of the energy deposition. We have compared MONET results with the FLUKA simulation in two cases: a single Gaussian beam and a lateral scan as a sum of many beams in order to estimate the accuracy of the model focusing on the tails of the distribution that give rise to the low-dose envelope. In both cases, we have obtained a good agreement for different energy of protons in water. The advantages are the physical foundation, the fast calculation time and the accuracy. Recently, MONET is extended to the case of Helium beam and preliminary results will be shown. A possible development is the creation of a dose database of clinical interest and an online fast dose evaluation tool.

• 10:25 - 10:50 Foroogh Khozeymeh Sarbishe (University of Kurdistan, Iran and University of Trento, Italy)
  "Analytical calculations of a race-track SiON resonator for biosensing application"

  In this work we present a new analytical formulation of a SiON racetrack resonator. The analytical modelling is based on the Conformal Transformation Method (CTM) and computes the effective refractive index of the whispering gallery modes at resonance. Results from analytical calculations are compared with experimental results measured on a racetrack resonator with a radius of 100μm and waveguide width of 1μm, coupled to the bus waveguide with fixed width at 900nm. The refractive index of SiON is chosen to be 1.66. This SiON racetrack resonator platform is also studied for biosensing applications. With calculation of effective refractive index changes for different glucose-water solutions of various concentrations we predict a bulk sensitivity of 78.16 nm/RIU. Finally, sensing measurements with real devices packaged into a microfluidic circuit have been performed. The Vertical Cavity Surface Emitting Laser (VCSEL) at 850 nm is used as a light source. Glucose water solutions at various concentrations are flown over the sensors. Volumetric sensing yields the sensitivity of 79.73 nm/RIU [1] that is in a good matching with analytical calculations. These results open up the path for fast sensitivity prediction and realization of small integrated and functional optical miniaturized biosensors.

CONDENSED MATTER PHYSICS II (chair: Emanuela Pusceddu)

• 11:20 - 11:45 Ekaterine Dadiani (Tbilisi State University, Georgia)
  "Singing paper strip"

  We consider the problem of paper strip (or grass), which is stretched from both sides, producing various sounds similar to a whistle by blowing across it. Sound waves are produced due to vibrations of the strip which are caused by air stream. Thus, this model describes the formation of sound waves and how it can be altered by just changing any of parameters in our problem (such as air velocity, surface linear density, tension force or dimensions of the strip). We have examined strip's oscillations theoretically by writing wave equation. It turns out that the oscillation frequency is not depended on the speed of air stream. We analyzed our experiments using Fourier transform and experimental results are in good agreement with our theoretical model. The next part of the problem is to somehow examine air stream velocity's dependence on sound volume. Because of the fact that this system is turbulent we have been unable to analytically find the amplitude of the strip for given parameters. We considered that air acts with chaotic force on the strip with some given range. This range is depended on air stream's velocity and surface area of the strip. The equation was solved numerically in Matlab and we were able to make animations of this motion. As expected, it turns out that although the force is chaotic, the system still performs oscillations on constant frequency with given range of amplitude. The volume of the sound is proportional to oscillation amplitude, so we compared these numerical results to experiments. So the main peculiarity of our model is that we approach hard aerodynamical problem originally and compare the results to our own conducted experiments.

• 11:45 - 12:10 Roberto Schimmenti (University of Palermo, Italy)
  "Boron Nitride Supported Sub-Nanometer Pd Clusters for Selective HCOOH Decomposition: A Computational Investigation"

• 12:10- 12:35 Mostafa Marzouk (Helwan University, Egypt)
  "High Tc Superconducting materials scattered by a Neutron source"

• 12:35 - 13:00 Giovanna Pintori (University of Trento, Italy)
  "Relaxation dynamics in borate glass formers probed by photon correlation at the microscopic and macroscopic length scale"

  X-ray photon correlation is used to probe the dynamics of the strong glass former boron trioxide and of a series of alkali borate glasses, (M2O)x(B2O3)1-x where M is the alkali modifier (M=Li, Na and K). The decay times τ of the obtained correlation functions in B2O3 are consistent with visible light scattering results and independent of the incoming beam intensity in the undercooled liquid phase; are instead temperature independent and show a definite dependence on the X-ray beam intensity in the glass. We are therefore witnessing an atomic dynamics induced by the X-ray beam, similarly to what recently observed in silica and germania. Furthermore, we clearly demonstrate that the value of τ is related to absorption by investigating a series of alkali borate glass with the same molar ratio and as a function of the alkali modifier. Finally, we highlight the role played by the structure in the X-ray induced dynamics by studying a series of lithium borate glasses with different molar ratios. Despite the observed dynamics is clearly intensity dependent, we obtain very interesting information on glasses not available with other experimental techniques.

ASTROPHYSICS II (chair: M. Cadeddu)

• 14:30 - 14:55 Mario Cadelano (University of Bologna, Italy)
  "The physics of millisecond pulsars in globular clusters"

  Millisecond pulsars are old and rapidly spinning neutron stars formed in binary systems through mass accretion from an evolving companion star. Although they can be found in the whole Galaxy, their number is highly enhanced in globular clusters. In fact, the collisional environment of these stellar systems promotes the continuous formation of new binary systems, suitable for recycling old and inactive neutron stars into millisecond pulsars. The study of millisecond pulsars in globular clusters is crucial in many fields, from astrophysics to nuclear physics. For example, they can be used to shed light on binary system evolution and on stellar evolution under extreme conditions but they can be also used to probe the equation of state of matter at ultrahigh densities and to test gravitational theories. Here I will present some results of my research work. 1) I will discuss a new method to identify the most weak and elusive millisecond pulsars in globular clusters. Indeed these systems are faint radio sources located in distant stellar systems. The discovery of additional pulsars in each cluster is a crucial step to understand the properties of the whole cluster neutron star population. 2) I will show how long-term, extremely precise timing of the pulsar pulses can be used to infer a wealth of information about the orbital properties of the binaries (including relativistic orbital effects) and about the cluster itself (e.g. cluster gravitational wells, proper motions, etc...). 3) Finally, I will discuss how the study of their optical counterparts is a key ingredient to unveil the evolutionary paths of such exotic objects. Indeed, different classes of millisecond pulsars could be explained by the properties of their companion stars, visible exclusively through optical observations.

• 14:55 - 15:20 Giampaolo Benevento (University of Padova, Italy)
  "Forecasting the power of next generation cosmological surveys in probing alternative theories of gravity"

  Cross-correlations between Cosmic Microwave Background (CMB) and tracers of large scale structure, like the galaxy distribution, provide a powerful tool to probe the growth history of cosmic structures. This can be exploited to build tests of Dark Energy and Modified Gravity. In this talk I will discuss CMB-galaxy cross-correlation in K-mouflage theories: a class of modified gravity models which can account for the current accelerated expansion of the Universe and include a screening mechanism to satisfy General Relativity solar system constraints. I will first review how we included K-mouflage theories in the EFTCAMB Einstein-Boltzmann solver, using a mapping of K-mouflage in Effective Field Theory of Dark Energy. I will then show how, using this code, we solved the full set of linearly perturbed Einstein and Boltzmann equations and computed K-mouflage matter and CMB power spectra, as well as other cosmological observables like the CMB-lensing potential. Thanks to these results, we were able to extract the expected CMB-galaxy cross-spectra in K-mouflage for several upcoming surveys. Moreover, we validated our codes using a semi-analytical approach, in which we numerically integrated the background evolution and the growth factor equations for different K-mouflage models, and compared with the fully numerical EFTCAMB solutions. As an application of the numerical tools described above, I will finally show Fisher matrix forecasts of K-mouflage parameters, discussing their detectability with forthcoming LSS surveys, such as Euclid or LSST. Our results confirm that future surveys are expected to strongly improve our power to probe different cosmological models and alternative theories of gravity.

• 15:20 - 15:45 Francesca Lepori (SISSA, Italy)
  "Relativistic effects in the neutral hydrogen and galaxy redshift survey cross-correlation"

  Inhomogeneities in the distribution of galaxies trace the underlying inhomogeneous distribution of dark matter. Therefore, galaxy surveys are crucial for testing the growth of dark matter perturbations and the theory of gravitation. The observable quantity in a galaxy survey is the galaxy number count, i.e. the observed fluctuation of the number of galaxies in a redshift bin at a certain solid angle. Beside the density perturbation, the velocity and the metric perturbations distort our observed coordinate system and therefore affect the observable. These distortions are often referred to as "relativistic effects", since their systematic computation requires to solve the geodesic equations for the observed photons' path. Relativistic effects need to be included in the cosmological analysis in order to fully exploit the improved precision and accuracy of the upcoming experiments. Moreover, their detection would provide a consistency test for general relativity. While they result to be subdominant in a single tracer analysis, some of these distortions can be isolated and detected by cross-correlating two different tracers. In my talk I will introduce a general model for the cross-correlation of galaxies and neutral hydrogen, observed in intensity mapping through the 21-cm emission line. Then I will present a signal-to-noise analysis of the relativistic signal for this cross-correlation. This analysis aims to define the properties of a galaxy survey that boost the signal-to-noise ratio and therefore will be optimal for detecting the relativistic effects. Finally, I will discuss the cosmological implications of the detection of the relativistic distortions.

• 16:15 - 16:40 Riccardo Murgia (SISSA, Italy)
  "Dark matter at small scales: a general approach"

  According to the standard cosmological model (ΛCDM model), the present universe is mainly composed by a cosmological constant (Λ) and by cold dark matter (CDM). Whereas this standard paradigm is favoured by cosmic microwave background and large scale structure data, it appears to display tensions with small-scale data. These small-scale problems could be solved either by baryon physics, still not perfectly understood and implemented in cosmological simulations, or by modifying the nature of dark matter. The effect of the existence of “non-cold” dark matter particles is a suppression of the matter power spectrum P(k) on small scales, usually described by the so-called transfer function T^2(k) = P_WDM(k)/P_ΛCDM(k). Therefore, many “non-cold” dark matter candidates have been proposed in order to give a better description of the structure formation and distribution at small scales, with respect to the ΛCDM model. Most of the constraints which have been published so far, refer to a very specific shape of the power suppression, corresponding to thermal warm dark matter, i.e. candidates with a Fermi-Dirac momentum distribution. Nonetheless, most of the viable dark matter candidates do not have a thermal momentum distribution. In this talk, I will introduce a new analytical fitting formula for the transfer function T(k), which is able to reproduce a large variety of shapes in the suppression of the power spectrum. I will explicitly show that it covers the parameter space of sterile neutrinos (whether resonantly produced or from scalar decays), mixed cold and warm models, fuzzy dark matter and other models suggested by effective field theory of structure formation. Finally, I will present the first astrophysical constraints on its free parameters by using two key observables: the number of Milky Way satellites and the Lyman-α forest. This is the first step towards a general comprehensive modeling of small-scale departures from the standard cosmological model.

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DETECTORS FOR PARTICLE PHYSICS (chair: E. Incani)

• 9:35 - 10:00 Riccardo Mirabelli (University of Rome 'La Sapienza' - INFN, Italy)
  "MONDO: A tracker for the characterization of secondary fast and ultrafast neutrons emitted in Particle Therapy"

  Particle Therapy (PT) is modern technique that exploits charged ions for the treatments of tumour becomes too risky for the closely localise to organ at risk. However, a non negligible amount of additional dose is deposed due to the contribution of secondary charged and neutral particles emitted from the fragmentation of the therapeutic beam with the patient's tissues. In particular, neutrons are the most dangerous secondary radiation because, due to the their interaction length, they can release energy far away from the treated area, increasing the risk of developing a radiogenic secondary malignant neoplasms many decades after undergoing a treatment. A precise characterization of this secondary component is eagerly needed in order to improved the Treatment Planning System (TPS) codes and predict the normal tissue toxicity. The request becomes particularly relevant in the case of paediatric treatments where life expectancy is a fundamental parameter. The main goal of the MONDO (MOnitor of Neutron Dose for hadrOntherapy) project is to develop a tracker for fast and ultrafast neutrons ([20-400] MeV) emitted during PT. The detector, based on the reconstruction of recoil protons emitted in two consecutive (n,p) elastic scattering interactions, is composed by a matrix of orthogonal layers of thin scintillating fibres (total size 10x10x20 cm^3). The readout consists in a tailored sensor (SBAM) based on digital-SPAD array developed in CMOS technology by Fondazione Bruno Kessler. The detector is under construction and a first prototype has been tested with electrons at the Beam Test Facility of Frascati and is going to be tested at Trento Proton Therapy Center in May 2017. Experimental results, efficiency studies, light yield measurements and the FLUKA MonteCarlo simulation of the detector will be presented.

• 10:00 - 10:25 Valentina Dompe (University of Rome 'La Sapienza' - Rome, Italy)
  "The CUORE experiment at LNGS"

  During the last decades, one of the main goals of experimental neutrino physics has become the observation of an extremely rare phenomenon, the neutrinoless double beta decay, which occurrence can provide many informations on neutrino Dirac or Majorana nature as well as its absolute mass scale. The Cryogenic Underground Observatory for Rare Events (CUORE) at Gran Sasso National Laboratories (LNGS), in Italy, focuses on the search of neutrinoless double beta decay of 130Te isotope. This is the first bolometric experiment searching for this process that has been able to reach the 1-ton scale, namely the largest bolometric detector ever realized. The detector is stored inside a cryostat and consists of an array of 988 TeO2 crystals of natural isotopic composition, for a total mass of 741 kg. The base temperature of operation is ~10 mK: the cryogenic temperature is reached and maintained thanks to a particular cooling system that has the advantage to avoid the usage of cryogenic liquids. The construction of the experiment and, in particular, the installation of all the towers in the cryostat was completed in August 2016 and commissioning started in fall 2016. All the cryostat radiation shields have been closed within the end of 2016, and the cooldown phase has been completed as well, with the reach of the base temperature at the end of January 2017. The experiment has just concluded the pre-operation phase and data taking is currently commencing.

• 10:25 - 10:50 Roberto Mulargia (University of Turin - INFN, Italy)
  "Ultra-Fast Silicon Detectors for 4D tracking"

  The evolution of particle detectors has always pushed the technological limit in order to provide enabling technologies to researchers in all fields of science. Silicon sensors are the most common type of particle detectors used for charged particle tracking, however their rather poor time resolution limits their use as precise timing detectors. I will present a recent advancement in silicon detectors technology which can enable the inclusion of very accurate timing information. This change in the present silicon detector paradigm is enabled by the inclusion of controlled, low gain in the detector response, therefore enhancing the detector output signal enough to make timing measurement possible. The Ultra-Fast Silicon Detectors, based on the Low Gain Avalanche Detector (LGAD) technology, grant the possibility of obtaining a measurement of space and time with a very high accuracy (10 micrometers and 10 picoseconds). In addition to excellent position and timing resolution, this new family of particle detectors will be characterized by GHz counting capabilities, very low material budget, radiation resistance, fine granularity, low power, insensitivity to magnetic field, and affordability. The successful development of such a detector would potentially affect the design of the next generation of particle detectors. The timing information would allow the reconstruction algorithms to significantly increase their efficiency in high luminosity conditions (as expected in High Luminosity LHC), by helping to resolve the vertex-tracks association in events with multiple concurrent collisions. The possibilities of this technology extend to other fields of science, for example the detection of low energy x-rays and other applications in medical physics.

INVITED TALK

• 12:10 - 13:00 Carlos Mejia-Monasterio (Technical University of Madrid, Spain)
  "The Thermodynamics of the Small"

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Nicola Sestu, University of Cagliari, Italy
"Absorption F-Sum Rule for the Exciton Binding Energy in Methylammonium Lead Halide Perovskites"

Elisa Sechi, IOM-CNR Cagliari, Italy
"Porous silicon/polyaniline hybrid materials for photovoltaic applications"

Laura Mais, University of Cagliari, Italy
"Highly ordered TiO2-WO3 modified nanotubes array for photoelectrocatalytic oxidation of Methyl Orange"

Armando Galluzzi, University of Salerno, Italy
"Determination of the ferromagnetic transition temperature of a Cu(x)Ni(1-x) film by means of an evolution of the method based on the Arrot plots"

Paola Mocci, University of Cagliari, Italy
"Electronic and optical properties of Si-atoms substituted graphene nanoribbons"

Tsotne Dadiani, Tbilisi State University, Georgia
"Light rings in the falling liquid jet"

Simona Corgiolu, University of Cagliari, Italy
"Controlled amino-functionalization of gold surfaces by electrochemical deposition of diazonium salts"

Tommaso D'Agostino, University of Cagliari, Italy
"The subtle balance: a comparative study on the properties that favour permeation of antibiotics in bacteria"

Elina Nepomnyashchaya, Peter the Great St. Petersburg Polytechnic University, Russia
"Spectroscopic techniques to study the non-specific immune response"

Foroogh Khozeymeh Sarbishe, University of Kurdistan, Iran and University of Trento, Italy
"Sensitivity optimization in multi-WGM optical cylindrical biosensors"

Leonardo Bianchini, University of Florence, Italy
"High-resolution numerical simulations of astrophysical plasma turbulence: Comparison with observations by the Magnetospheric Multiscale NASA Mission"

Angelo Loi, University of Cagliari, Italy
"3D particle detectors with high space and time resolution"

Maura Spanu, INFN Pavia, Italy
"Study on TPB as wavelength shifter for the new ICARUS T600 light detection system in the SBN program"

Emanuele Picciau, University of Cagliari, Italy
"The role of neutrino background on next generation dark-matter experiments"

Hamid Basiri, Shahrood University, Iran
"Investigation of some possible changes in Am-Be neutron source configuration in order to increase the thermal neutron flux using Monte Carlo code"

Monika Richter, University of Silesia, Poland
"Quantum Cheshire Cat"

Piotr Chaber, University of Silesia, Poland
"The problem of neutrino masses in Two-Higgs-Doublet Model"

Gaetano Luciano,University of Salerno, Italy
"Non-thermal signature of the Unruh effect in field mixing"