bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tor vergata Synoptic Solar Telescope: preliminary optical design and spectral characterization
Authors: Calchetti D , Viavattene G , Berrilli F , Moro D Del , Giovannelli L , Oliviero M 
Published: May 2020

Abstract
Synoptic telescopes are fundamental tools in solar physics. They are tipically used for high cadence full-disk observations of the Sun at different wavelengths, in order to study the solar activity across the solar cycle. The TSST (Tor vergata Synoptic Solar Telescope) is a new synoptic telescope composed of a Ha filter-based telescope centered at 656 nm and a custom Magneto Optical Filter (MOF)-based telescope centered in the potassium (KI D1) absorption line at 770 nm. Observations of the Ha line are important for the detection of flaring regions and to track the Sun during the acquisition. The aim of the telescope is to monitor the solar activity using the line of sight (LoS) magnetograms and dopplergrams of the solar photosphere produced by the MOF-based telescope. Magnetograms are essential for the study of the geometry of the magnetic field in active regions, while dopplergrams can be used to study the dynamics of the solar lower atmosphere. In this work, we focus our attention on the custom MOF-based telescope. Firstly, we present the optical design of the instrument. It is a refractor telescope with a 80 mm aperture and an effective focal length of ∼1m. We also present details on the preliminary spectral characterization of this instrument at different cell temperatures, which is a mandatory step to calibrate magnetograms and dopplergrams. The results obtained during this first test are in agreement with the peaks separation (∼200 mÅ) and FWHM (∼ 50 mÅ) that we expected.
The QUBIC instrument for CMB polarization measurements
Authors: Mele L , Ade P , Alberro J G , Almela A , Amico G , Arnaldi L H , Auguste D , Aumont J , Azzoni S , Banfi S , Battistelli E S , Baù A , Bèlier B , Bennett D , Bergé L , Bernard J-Ph , Bersanelli M , Bigot-Sazy M-A , Bleurvacq N , Bonaparte J , Bonis J , Bottani A , Bunn E , Burke D , Buzi D , Cavaliere F , Chanial P , Chapron C , Charlassier R , Columbro F , Coppolecchia A , D’Alessandro G , Bernardis P de , Gasperis G De , Leo M De , Petris M De , Dheilly S , Dumoulin L , Etchegoyen A , Fasciszewski A , Ferreyro L P , Fracchia D , Franceschet C , Lerena M M Gamboa , Ganga K , García B , Redondo M E García , Gaspard M , Gayer D , Gervasi M , Giard M , Gilles V , Giraud-Heraud Y , Gómez Berisso M , González M , Gradziel M , Grandsire L , Hamilton J -Ch , Harari D , Henrot-Versillé S , Hoang D T , Incardona F , Jules E , Kaplan J , Kristukat C , Lamagna L , Loucatos S , Louis T , Maffei B , Marnieros S , Marty W , Masi S , Mattei A , May A , McCulloch M , Melhuish S , Mennella A , Montier L , Mousset L , Mundo L M , Murphy J A , Murphy J D , Nati F , Olivieri E , Oriol C , O’Sullivan C , Paiella A , Pajot F , Passerini A , Pastoriza H , Pelosi A , Perbost C , Perciballi M , Pezzotta F , Piacentini F , Piat M , Piccirillo L , Pisano G , Platino M , Polenta G , Prêle D , Puddu R , Rambaud D , Ringegni P , Romero G E , Salatino M , Salum J M , Schillaci A , Scóccola C , Scully S , Spinelli S , Stankowiak G , Stolpovskiy M , Tartari A , Thermeau J-P , Timbie P , Tomasi M , Torchinsky S , Tristram M , Tucker G , Tucker C , Viganò D , Vittorio N , Voisin F , Wicek F , Zannoni M , Zullo A 
Published: May 2020

Abstract
Measurements of cosmic microwave background (CMB) polarization may reveal the presence of a background of gravitational waves produced during cosmic inflation, providing thus a test of inflationary models. The Q&U Bolometric Interferometer for Cosmology (QUBIC) is an experiment designed to measure the CMB polarization. It is based on the novel concept of bolometric interferometry, which combines the sensitivity of bolometric detectors with the properties of beam synthesis and control of calibration offered by interferometers. To modulate and extract the input polarized signal of the CMB, QUBIC exploits Stokes polarimetry based on a rotating half-wave plate (HWP). In this work, we illustrate the design of the QUBIC instrument, focusing on the polarization modulation system, and we present preliminary results of beam calibrations and the performance of the HWP rotator at 300 K.
The penumbral solar filaments from the photosphere to the chromosphere
Authors: Murabito M , Ermolli I , Giorgi F , Stangalini M , Guglielmino S L , Jafarzadeh S , Socas-Navarro H , Romano P , Zuccarello F 
Published: May 2020

Abstract
The magnetic field structure of sunspots above the photosphere remain poorly understood due to limitations in observations and the complexity of these atmospheric layers. In this regard, we studied the large isolated sunspot (70”× 80”) located in the active region NOAA 12546 with spectro-polarimetric measurements acquired along the Fe I 617.3 nm and Ca II 854.2 nm lines with the IBIS/DST instrument, under excellent seeing conditions lasting more than three hours. Using the Non Local Thermodynamic Equilibrium inversion code we inverted both line measurements simultaneously to retrieve the three-dimensional magnetic and thermal structure of the penumbral region from the bottom of the photosphere to the middle chromosphere. The analysis of data acquired at spectral ranges unexplored allow us to show clear evidence of the spine and intra-spine structure of the magnetic field at chromospheric heights. In particular, we found a peak-to-peak variations of the magnetic field strength and inclination of about 200 G and 10° chromospheric heights, respectively, and of about 300 G and 20° in the photosphere. We also investigated the structure of the magnetic field gradient in the penumbra along the vertical and azimuthal directions, confirming previous results reported in the literature from data taken at the spectral region of the He I 1083 nm triplet.
The first flight of the OLIMPO experiment: instrument performance
Authors: Presta G , Ade P A R , Battistelli E S , Castellano M G , Colantoni I , Columbro F , Coppolecchia A , Alessandro G D’ , Bernardis P de , Gordon S , Lamagna L , Masi S , Mauskopf P , Paiella A , Pettinari G , Piacentini F , Pisano G , Tucker C 
Published: May 2020

Abstract
OLIMPO is a balloon-borne experiment aiming at spectroscopic measurements of the Sunyaev-Zel’dovich effect in clusters of galaxies. The instrument operates from the stratosphere, so that it can cover a wide frequency range (from ∼ 130 to ∼ 520 GHz in 4 bands), including frequencies which are not observable with ground-based instruments. OLIMPO is composed of a 2.6-m aperture telescope, a differential Fourier transform spectrometer and four arrays of lumped element kinetic inductance detectors operating at the temperature of 0.3 K. The payload was launched from the Longyearbyen airport (Svalbard Islands) on July 14th, 2018, and operated for 5 days, at an altitude of 38 km around the North Pole. We report the in-flight performance of the first lumped element kinetic inductance detector arrays ever flown onboard a stratospheric balloon.
Causal inference in space weather by an information theory approach
Authors: Stumpo M , Consolini G , Alberti T 
Published: May 2020

Abstract
The variability of the interplanetary medium and solar wind conditions strongly affects the near-Earth environment causing several phenomena, such as the magnetic storms and substorms. Here, we present some preliminary results on the causal inference in the solar wind-magnetosphere-ionosphere coupling by means of information theory which could be helpful for Space Weather modeling.
FRED: a fast Monte Carlo code on GPU for quality control in Particle Therapy
Authors: Simoni M De , Fischetti M , Gioscio E , Marafini M , Mirabelli R , Patera V , Sarti A , Schiavi A , Sciubba A , Traini G 
Published: May 2020

Abstract
Charged Particle Therapy is a non-invasive technique for radio-resistant tumor treatment performed with protons or light ions, aiming to deliver a high precision treatment. Compared to conventional radiotherapy, ions allow for a higher dose deposition in the tumor region while sparing the surrounding healthy tissue. To really exploit the potential benefits of this technique, the highest possible accuracy in the calculation of dose and its spatial distribution is required in treatment planning. Commonly used Treatment Planning Software solutions adopt a simplified beam-body interaction model. An alternative is the use of Monte Carlo simulations which explicitly take into account the interaction of charged particles with actual human tissues hence providing highly accurate results. However, Monte Carlo simulations are used in a restricted number of cases due to substantial computational resources required. The code FRED has been developed to allow a fast optimization of the treatment plans in Charged Particle Therapy while profiting from the dose release accuracy of a Monte Carlo tool. Currently, the most refined module is the transport of proton beams in water. A comparison with measurements shows that the lateral dose tails are reproduced within 2% in the field size factor test up to 20 cm. Models for the interaction of ion with the matter are currently under development in the FRED code. The status of new developments and the performance of FRED will be presented.
Silver doping effects on irreversibility field and pinning energy of a FeSe iron based superconductor
Authors: Galluzzi A , Buchkov K , Nazarova E , Leo A , Grimaldi G , Pace S , Polichetti M 
Published: May 2020

Abstract
We have performed DC magnetic moment measurements as a function of magnetic field m(H) and time m(t) on a FeSeo.94 and a silver doped FeSeo.94 + 6 wt% Ag. In particular, from the m(H) measurements, the field dependence of the critical current density Jc(H) of the samples has been extracted at different temperatures in the framework of the Bean critical state model. Starting from the Jc(H) of the samples, we have studied the influence of the silver doping on the temperature dependence of the irreversibility field Hirr(T) above which the pinning energy is so reduced that the vortices are free to move. The obtained Hirr(T) values have been fitted with the equation Hirr(T) = Hirr(0) (1-T/T*)n whose results have been compared with the literature. After that, we have analyzed the silver doping effects on the field dependence of the pinning energy U(H), extracted from relaxation measurements at different temperatures and magnetic fields, obtaining that both samples undergo to a pinning regime crossover.
Auxiliary lasers for Advanced Virgo Gravitational Wave detector using single pass Second Harmonic Generation in Periodically Poled Lithium Niobate crystal
Authors: Khan I , Genin E , Fafone V , Pillant G , Maggazu A , Casanueva J , Chiummo A , Leroy N 
Published: May 2020

Abstract
The Advanced Virgo (AdV) detector is composed of different degrees of freedom (DOFs) i.e. Michelson interferometer, two Fabry-Perot arm cavities, signal recycling cavity, and power recycling cavity. These DOFs need to be locked to precise accuracy with robust, fast and reliable control systems. The control signals used to lock all the DOFs are mildly decoupled in frequency and the optical response of the DOFs are nonlinear, where the linear range of operation is just some percentage of the fringe for each DOF, thus posing difficulty in resonance lock at input laser wavelength for all the cavities. In particular, the control status of the arm cavities can alter the state of the detector’s operational configuration. Using Auxiliary Lasers to lock the arm cavities at different wavelength offers flexible and robust lock of the detector and more spatial margin on the control signals. Second harmonic generation offers the most direct way to have laser beam with different wavelength and phase locked to the AdV input laser beam. We generated upto 97 mW of SH beam in single configuration at 532 nm using fibered amplified laser source at 1064 nm in a 10 mm long Poled Lithium Niobate crystal.
The key role of the Silicon Drift Detectors in testing the Pauli Exclusion Principle for electrons: the VIP-2 experiment
Authors: Paolis L De , Amirkhani A , Bartalucci S , Bertolucci S , Bazzi M , Bragadireanu M , Cargnelli M , Clozza A , Curceanu C , Grande R Del , Egger J P , Fiorini C , Guaraldo C , Iliescu M , Laubenstein M , Marton J , Mazzocchi T , Miliucci M , Milotti E , Pichler A , Pietreanu D , Piscicchia K , Scordo A , Shi H , Sirghi D L , Sirghi F , Sperandio L , Vazquez Doce O , Veith M , Zmeskal J 
Published: May 2020

Abstract
The VIP experiment performed an accurate investigation of the Pauli Exclusion Principle for electrons. The apparatus was installed in the Gran Sasso Laboratories of the National Institute of Nuclear Physic in Italy, an underground environment with an extremely low cosmic background. The aim of the experiment was to test the Pauli Exclusion Principle for electrons in a copper target circulated by a Direct Current (DC) current, searching for X-rays emission due to an atomic transition forbidden by Pauli exclusion principle, from the L shell to the K shell of copper when the K shell is already occupied by two electrons. VIP set an upper limit on the Pauli exclusion principle violation probability 1/2β
2 <4.7 χ 10–29. The goal of the upgraded VIP-2 experiment, presently in data taking at Gran Sasso Laboratories, is to improve this limit by two orders of magnitude. The VIP-2 experimental apparatus, in which the Silicon Drift Detectors have the key role of X-ray detectors, and preliminary results are presented.
Unlocking neutrino mysteries via the inverse β-decay
Authors: Blasone M , Lambiase G , Luciano G G , Petruzziello L 
Published: May 2020

Abstract
We discuss some recent results on neutrino physics in the context of the inverse β-decay of uniformly accelerated protons. Specifically, we compute the decay rate of the process p → n + e
+ + ν in both the laboratory frame (where the proton is non-inertial) and the comoving frame (where the proton is at rest and interacts with a thermal bath of electrons and neutrinos due to the Unruh effect). On the basis of the sole requirement of General Covariance of Quantum Field Theory, we manage to show that: i) the asymptotic (i.e. “in” and “out” ) neutrino states to be used for the evaluation of the S-matrix are Pontecorvo flavor eigenstates, ii) the Unruh thermal bath must be made up of oscillating neutrinos.
Factorisation and Local Subtraction of Infrared Divergences for QCD processes
Authors: Signorile-Signorile C 
Published: May 2020

Abstract
We review a recently proposed subtraction procedure at next-to- and next-to-next- to-leading order in quantum chromodynamics (QCD), based on the introduction of a set of minimal, local and analytically integrable counterterms. We also provide an operator definition for the counterterms by investigating the factorisation properties of a generic massless virtual amplitude. Our local, analytic scheme is designed for massless final state radiation only, but its main features are extensible to initial state radiation.
Efficiency enhancement in Dye Sensitized Solar Cells by light scattering in photoanode with TiO2 nanotubes
Authors: Senadeera G K R , Thotawatthage C A , Dissanayake M A K L 
Published: May 2020

Abstract
The effect of incorporating a composite double layered structure of photoanode, based on hydrothermally synthesized TiO2 nanotubes (TNT) as the light scattering layer, on the efficiency enhancement of dye sensitized solar cells (DSSCs) is reported. Device performances comprising this novel photoanode is compared with the DSSCs fabricated with the conventional type of photoanodes without TNT. Further enhancement in the device performances is obtained with the post treatment of the photoanode with TiCl4. The DSSC with post treated two layered composite photoanode showed an overall efficiency of 8.31% with a short circuit photocurrent density (Jsc
) of 16.91 mA cm−2 and 783.4 mV of an open circuit voltage (V
oc) under the irradiance of 1000 W m−2. In comparison, the reference DSSC with a post treated photoanode having the same thickness showed 7.62% efficiency while delivering a Jsc
of 15.60 mA cm−2 with 773.5 mV. The remarkable enhancement in the device performance is achieved due the employment of this double-layered novel photoanode in the DSSCs. However, lower electron life time is observed in the DSSCs with TNT layer suggesting that, rate of electron recombination is higher in the DSSCs with this novel photoanode, although the overall efficiency of the present device and the net result due to the enhanced light harvesting and scattering effect may still be regarded as an favorable alternative for certain applications.
Heating Effects on Optical Properties of Metal Nano Particle
Authors: Iskandar Alexander A. , Isro Suhandoko D. , Wulandari Priastuti 
Published: May 2020

Abstract
Localized Surface Plasmon (LSPR) occurs on the interface of Metal Nano Particle (MNP) when illuminated with electromagnetic wave, at a specific electromagnetic energy (wavelength). In this work, we model the gold nanoparticle (AuNP) composite by its atomic polarizability, that is related to the absorption, and its dependence on temperature. To compare the resulted LSPR frequency shift when the AuNP system is heated, we synthesized the MNP composite of polymer (oleylamine) capped gold nanoparticle (AuOA) and measured the optical properties which is related to the LSPR resonance frequency through the atomic polarizability of the composite. The temperature dependence effect is observed by depositing the AuAO onto a thin film after mixing with a polymer solvent (P3HT : PCBM) and heating it. It is found that a perceptible blueshift of the LSPR signal is observed which is contrary to the prediction from the model. This effect can be attributed to the thermal expansion of the thin films due to the heating process. After heating, the relative distance between two nanoparticles becomes larger, thus the weakening of surface plasmon interaction between the particles.
Humidity Effects on the Growth of ZnO Nanorods using Hydrothermal Method
Authors: Jali Mohd Hafiz , Rahim Hazli Rafis Abdul , Yusof Haziezol Helmi Mohd , Johari Md Ashadi Md , Thokchom Siddharth , Harun Sulaiman Wadi 
Published: May 2020

Abstract
The effects of ZnO nanorod samples with different growth times samples to the morphological structures and output light intensity are reported. The proposed structure comprises of silica microfiber integrated with Zinc Oxide (ZnO) nanorods coated glass surface. The silica microfiber is tapered into constant waist diameter of 10 μm using flame brushing technique. While the glass surface is coated with ZnO nanorods using hydrothermal method for 6 hours, 9 hours, 12 hours, 15 hours and 18 hours growth times. The samples are exposed to the different humidity levels ranging from 35%RH to 85%RH to observe the effect of the morphological structures such as length, diameter and density and the output light intensity. The resulted measurements provide the correlation between the growth time during the synthesis process to the ZnO nanorods physical structure as well as the output light intensity in different humidity levels. It utilizes the unique features of the scattering and surface absorption of the microfiber and ZnO nanomaterials coated glass surface to alter the output light intensity. The reported results may contribute to the optimal ZnO nanorods growth time for humidity sensing applications.
ZnO-Mg Nanoparticles Produced by Pulsed Laser Ablation in Liquid (PLAL) Technique
Authors: Yudasari N , Suliyanti M M , Imawan C 
Published: May 2020

Abstract
Pulsed laser ablation in liquid (PLAL) technique has been used to synthesize ZnO and ZnO-Mg nanoparticles by conducting laser ablation of zinc target in pure water and Mg(NO3)2 solution. The absorbance spectra show redshifted peaks of ZnO with Mg inclusion indicating the lowering of the band-gap energy down to 3.09 and 3.01 eV from 3.28 eV of the pure ZnO. The higher frequency visible emission peaks of ZnO-Mg in the photoluminescence spectra indicate more recombination due to the formation of Mg interstitial state. The XRD measurement shows the diffraction of ZnO-Mg shifted into lower peak, resulting longer interplanar spacing, which matches to those obtained from HRTEM measurement.
Prospects of nuclear clustering studies via dissociation of relativistic nuclei in nuclear track emulsion
Authors: Artemenkov D A , Bradnova V , Firu E , Haiduc M , Kornegrutsa N K , Malakhov A I , Mitsova E , Neagu A , Peresadko N G , Rusakova V V , Stanoeva R , Zaitsev A A , Zarubina I G , Zarubin P I 
Published: May 2020

Abstract
Status and prospects of nuclear clustering studies by dissociation of relativistic nuclei in nuclear track emulsion are presented. The unstable 8Be and 9B nuclei are identified in dissociation of the isotopes 9Be, 10B, 10C and nC, and the Hoyle state in the cases 12C and 16O. On this ground searching for the Hoyle state and more complex α-particle states in the dissociation of the heavier nuclei is suggested. A detailed study of a low-density baryonic matter arising in dissociation of the heaviest nuclei is forthcoming long-term problem. An analysis of nuclear fragmentation induced by relativistic muons is proposed to examine the mechanism dissociation.
Monte Carlo Simulations for Shielding Analysis of the TR-24 Cyclotron at INRNE-BAS
Authors: Demerdjiev A , Goutev N , Asova G , Shegunov K , Dimitrov D T , Tonev D 
Published: May 2020

Abstract
The Institute for Nuclear Research and Nuclear Energy at the Bulgarian Academy of Sciences is building an accelerator laboratory to operate a TR-24 cyclotron. Thus, a preliminary radiation shielding analysis of the accelerator bunker is required. For this purpose Monte-Carlo simulations have been performed and dosimetric (Dose equivalent) quantities have been estimated in two model geometries - simplified spherical geometry and full-scale bunker, respectively during operation and after the end of the cyclotron life. Our current efforts are directed to the production of 18F thus in all the conducted simulations a water target enriched with 18O is considered. NiGa3 as a target for production of 68Ge has also been simulated and a comparison of the radiation shielding characteristics of the bunker for the two targets has been made.
Gamma-ray emission in alpha-particle reactions with C, Mg, Si, Fe
Authors: Kiener J. , Bundesmann J. , Deloncle I. , Denker A. , Tatischeff V. , Gostojic A. , Hamadache C. , Röhrich J. , Benhabiles H. , Bourgaoub I. , Coc A. , Hammache F. , Mezhoud R. , Peyré J. 
Published: May 2020

Abstract
Cross sections for the strongest γ-ray emission lines produced in α-particle reactions with C, Mg, Si, Fe have been measured in the range E

α
= 50-90 MeV at the center for protontherapy at the Helmholtz-Zentrum Berlin. Data for more than 60 different γ-ray lines were determined, with particular efforts for lines that are in cross section compilations/evaluations with astrophysical purpose, and where data exist at lower projectile energies. The data are compared with predictions of a modern nuclear reaction code and cross-section curves of the latest evaluation for gamma-ray line emission in accelerated-particle interactions in solar flares.
Quasi-exact solutions for the Bohr Hamiltonian with sextic oscillator potential
Authors: Buganu P. , Budaca R. , Chabab M. , Lahbas A. , Oulne M. 
Published: May 2020

Abstract
A discussion on the quasi-exact solution of the Bohr Hamiltonian with sextic oscillator potential is made by attracting the attention on some recent results of its application to the phase transition from spherical vibrator to a γ-unstable system. More precisely, it is underlined the importance of the solvability order on the structure of the states, especially in the critical point, respectively, in the deformed region of the phase transition.