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A preliminary simulation study of influence of backsplash on the plastic scintillator detector design in HERD experiment

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Radiation Detection Technology and Methods 2021年第3期5卷 332-338页

作者： Peng Hu Zhi-gang Wang Fabio Gargano Francesca Alemanno Corrado Altomare Tian-wei Bao Yong-wei Dong Valerio Formato dimitrios Kyratzis Nicola Mori Lorenzo Pacini Zheng Quan Davide Serini Jun-jing Wang Rui-jie Wang Ming Xu Bo-bing Wu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Istituto Nazionale di Fisica Nucleare(INFN) Sezione di Bari70126 BariItaly Gran Sasso Science Institute(GSSI) 67100 L’AquilaItaly Istituto Nazionale di Fisica Nucleare(INFN) Laboratori Nazionali del Gran Sasso67100 L’AquilaItaly dipartimento Interateneo di Fisica dell’Universitàe del Politecnico di Bari 70125 BariItaly Istituto Nazionale di Fisica Nucleare(INFN) Sezione di Roma Tor Vergata00133 RomeItaly Istituto Nazionale di Fisica Nucleare(INFN) Sezione di Firenze50019 Sesto FiorentinoItaly

Background The plastic scintillator detector(PSD)is one of the detectors in the high energy cosmic radiation detection(HERD)facility,which is designed for gamma-ray detection and a redundant charge measurement.Backsplash will lead to a decrease in PSD’s performance of gamma-ray detection and charge measurement,which should be carefully considered.Purpose Two preliminary segmentation schemes of the PSD and two veto strategies have been proposed to suppress the backsplash effect.In this paper,we focus on the influence of the backsplash caused by gamma rays.The gamma-ray trigger efficiency and identification efficiency were studied in the case of different cell sizes and veto strategies,which can provide guidance on the PSD design.Methods A Monte Carlo simulation based on Geant4 has been performed.To simplify the simulation,the PSD is segmented into 1 cm3 cubes which can be easily aggregated into cells with different sizes during analysis.Results and conclusion Side_Veto can be used as a baseline design of veto strategy,whereas Smart_Veto can be selected as an upgraded design.Both the PSD bar cell with a width of less than 11 cm and the PSD tile cell with a width of less than 20 cm can achieve a sufficiently high gamma-ray trigger efficiency(>80%),which realizes the primary goal of the PSD.Meanwhile,both the PSD bar cell with a width of less than 3 cm and the PSD tile cell with a width of less than 20 cm can ensure a sufficiently high gamma-ray identification efficiency(>80%)for photons up to 800 GeV.

关键词： Plastic scintillator detector Gamma-ray detection Backsplash Veto

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Geodynamics of the Calabrian Arc area (Italy) inferred from a dense GNSS network observations

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Geodesy and Geodynamics 2016年第1期7卷 76-86页

作者： Oiuseppe Casula Istituto Nazionale di Geofisica e Vulcanologia (INGV) Sezione di Bologna Via Donato Creti 12 1-40128 BolognaItaly

The tectonics and geodynamics of the Calabria region are presented in this study. These are inferred by precise computation of Global Navigation Satellite Systems （GNSS） per~ manent station velocities in a stable Eurasian reference framework. This allowed computation of the coordinates, variance and covariance matrixes, and horizontal and vertical velocities of the 36 permanent sites analyzed, together with the strain rates, and using different techniques. Interesting geodynamic phenomena are presented, including compressional, and deformational fields in the Tyrrhenian coastal sites of Calabria, extensional trends of the Ionian coastal sites, and sliding movement of the Crotone Basin. Conversely, on the northern Tyrrhenian side of the network near the Cilento Park area, the usual extensional tectonic perpendicular to the Apennine chain is observed. The large- scale pattern of the GNSS height velocities is shown, which is characterized by general interesting geodynamic vertical effects that appear to be due to geophysical movement and anthropic activity. Finally, the strain-rate fields computed through three different tech- niques are compared.

关键词： Global Navigation Satellite Systems（GNSS）GeodesyGeodynamicsCalabrian ArcStrain rateTectonicsReference frameNetwork adjustment

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Phase Contrast Micro-Computed Tomography of Biological Sample at SSRF

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Tsinghua Science and Technology 2010年第1期15卷 102-107页

作者：陈荣昌谢红兰 Luigi Rigon 杜国浩 Edoardo Castelli 肖体乔 Shanghai Institute of Applied Physics Chinese Academy of Sciences Department of Physics University of Trieste INFN Sezione di Trieste

In line X-ray phase contrast micro-computed tomography （IL-XPCT）, which can be implemented at third generation synchrotron radiation sources or by using a micro-focus X-ray tube, is a powerful technique for non-destructive, high-resolution investigations of a broad variety of materials. At the Shanghai Synchrotron Radiation Facility （SSRF）, the X-ray Imaging and Biomedical Applications Beamline was built and started regular user operation in May 2009. Both qualitative （without phase retrieval） and quantitative （with phase retrieval） three-dimensional IL-XPCT experimental techniques have been established at the beamline IL-XPCT experiments of a test sample （plastic pipes） used to evaluate the technique, and of a biological sample （locust） at the beamline are reported. Two series of images, qualitative and quantitative, including tomographic slices and three-dimensional rendering images were obtained. In qualitative images, there is a strong edge-enhancement which leads to very clear sample contours, while in quantitative images, the edge-enhancement fades but quantitative measurement of sample＇s phase information could be achieved. The experiments demonstrate that the combination of qualitative and quantitative images is useful for biological sample studies.

关键词： X-ray phase contrast tomography phase retrieval synchrotron radiation

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CPT INVARIANCE TESTS IN NEUTRAL KAON DECAY

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Chinese Physics C 2016年第10期40卷 707-709页

作者： M. Antonelli LNF-INFN, Frascati LNF-INFN Frascati INFN sezione di Napoli

CPT theorem is based on three assumptions： quantum field theory, locality, and Lorentz invariance, and thus it is a fundamental probe of our basic understanding of particle physics. Strangeness oscillation in K^0 -K^... 详细信息

关键词： CPT定理介子衰变 Lorentz 中性测试变性量子场论粒子物理

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An extended assessment of bowel habits in a general population

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World Journal of Gastroenterology 2004年第5期10卷 713-716页

作者： Gabrio Bassotti Massimo Bellini Filippo Pucciani Renato Bocchini Antonio Bove Pietro Alduini Edda Battaglia Paolo Bruzzi sezione di Gastroenterologia ed Epatologia Dipartimento di Medicina Clinica e SperimentaleUniversità di Perugia sezione di Gastroenterologia Dipartimento di Medicina InternaUniversità di Pisa Clinica Chirurgica Generale e discipline Chirurgiche Università di Firenze UO di Medicina Polispecialistica Azienda Sanitaria LocaleCesena UO di Gastroenterologia ed Endoscopia digestiva Azienda Ospedaliera"A.Cardarelli"Napoli dipartimento di Fisiopatologia Clinica Università di Torino Struttura Complessa di Epidemiologia Clinica IST GenovaItaly

AIM:Bowel habits are difficult to study, and most data on defecatory behaviour in the general population have been obtained on the basis of recalled interview. The objective assessment of this physiological function and its pathological aspects continues to pose a difficult challenge. The aim of this prospective study was to objectively assess the bowel habits and related aspects in a large sample drawn from thegeneral population.METHODS: Over a two-month period 488 subjects were prospectively recruited from the general population and asked to compile a daily diary on their bowel habits and associated signs and symptoms (the latter according to Rome Ⅱ criteria). A total of 298 (61%) participants returned a correctly compiled record, so that data for more than 8000 patient-days were available for statistical analysis.RESULTS:The average defecatory frequency was once per day (range of 0.25-3.25) and was similar between males and females.However, higher frequencies of straining at stool (P=0.001), a feeling of incomplete emptying and/or difficult evacuation (P=0.0001), and manual manoeuvres to facilitate defecation (P=0.046) were reported by females as compared to males.CONCLUSION:This study represents one of the first attempts to objectively and prospectively assess bowel habits in a sample of the general population over a relatively long period of time. The variables we analyzed are coherent with the criteria commonly used for the clinical assessment of functional constipation, and can provide a useful adjunt for a better evaluation of constipated patients.

关键词：肠道习性肠道疾病卫生统计影响因子

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Relativistic correction to gluon fragmentation function into pseudoscalar quarkonium

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Chinese Physics C 2017年第2期41卷 55-63页

作者：高祥瑞贾宇李留记熊小努 Institute of High Energy Physics and Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Center for High Energy Physics Peking University Istituto Nazionale di Fisica Nucleare Sezione di Pavia

Inspired by the recent measurements of the ηc meson production at LHC experiments, we investigate the relativistic correction effect for the fragmentation functions of gluon/charm quark fragmenting into ηc, which constitute the crucial nonperturbative element for the ηc production at high pT. Employing three distinct methods,we calculate the next-to-leading-order（NLO） relativistic correction to g →ηc fragmentation function in the NRQCD factorization framework, as well as verifying the existing NLO result for the c →ηc fragmentation function. We also study the evolution behavior of these fragmentation functions with the aid of the DGLAP equation.

关键词： QCD heavy quarkonium fragmentation function DGLAP equation

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Functional topography of the corpus callosum investigated by DTI and f MRI

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World Journal of Radiology 2014年第12期6卷 895-906页

作者： Mara Fabri Chiara Pierpaoli Paolo Barbaresi Gabriele Polonara dipartimento di Medicina Sperimentale e Clinica Sezione di Neuroscienze e Biologia Cellulare Università Politecnica delle Marche dipartimento di Scienze Cliniche Specialistiche e Odontostomatologiche Sezione di Scienze Radiologiche Università Politecnica delle Marche

This short review examines the most recent functional studies of the topographic organization of the human corpus callosum, the main interhemispheric commissure. After a brief description of its anatomy, development, microstructure, and function, it examines and discusses the latest findings obtained using diffusion tensor imaging(DTI) and tractography(DTT) and functional magnetic resonance imaging(f MRI), three recently developed imaging techniques that have significantly expanded and refined our knowledge of the commissure. While DTI and DTT have been providing insights into its microstructure, integrity and level of myelination, f MRI has been the key technique in documenting the activation of white matter fibers, particularly in the corpus callosum. By combining DTT and f MRI it has been possible to describe the trajectory of the callosal fibers interconnecting the primary olfactory, gustatory, motor, somatic sensory, auditory and visual cortices at sites where the activation elicited by peripheral stimulation was detected by fMRI. These studies have demonstrated the presence of callosal fiber tracts that cross the commissure at the level of the genu, body, and splenium, at sites showing f MRI activation. Altogether such findings lend further support to the notion that the corpus callosum displays a functional topographic organization that can be explored with f MRI.

关键词： Corpus callosum Interhemispheric transfer Functional magnetic resonance imaging and diffusion tensor imaging Brain imaging Topographic organization

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FORM FACTORS FOR RAdiATIVE PION AND KAON DECAYS

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Chinese Physics C 2016年第10期40卷 685-686页

作者： M. Bychkov G. D'Ambrosio University of Virginia INFN sezione di Napoli

The radiative decays, π^± → l^±vγ and K^± →l^±vγ, with 1 standing for an e or a μ, and γ for a real or virtual photon （e＋e- pair）, provide a powerful tool to investigate the hadronic structure of pions and kaons. The structuredependent part Sdi of the amplitude describes the emission of photons from virtual hadronic states, and is parametrized in terms of form factors V,A, （vector, axial vector）,

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General Relativity and the Tully-Fisher Relation for Rotating Galaxies

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Journal of Modern Physics 2022年第11期13卷 1452-1473页

作者： Yogendra Srivastava Giorgio Immirzi John Swain Orlando Panella Simone Pacetti Emeritus Professor of Physics Northeastern University Boston MA USA dipartimento di Fisica e Geologia Università di Perugia Perugia Italy Retired Dipartimento di Fisica e Geologia Università di Perugia Perugia Italy Physics Department Northeastern University Boston MA USA Istituto Nazionale di Fisica Nucleare INFN Sezione di Perugia Perugia Italy

The flat limit of rotational velocity (vφ) approximately equal to the “edge”-velocity of a galaxy is related to the baryonic mass (MB) via the T-F relationship with n ≈ 4. We explore the connection between mass and the limiting velocity in the framework of general relativity (GR) using the Weyl metric for axially-symmetric galaxies that are supported entirely by their rotational motion. While for small distances from the center, the Newtonian description is accurate as one moves beyond the (baryonic) edge of the galaxy, Lenz’s law and non-linearity of the gravitational field inherent in GR not only lead to a flat velocity (obviating its Keplerian fall), but also provide its tight log-log relationship with the enclosed (baryonic) mass.

关键词： GR Weyl Metric Rotating Galaxies Flat Rotation Curves TF Relation

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Effects of Λ hyperons on the deformations of even–even nuclei

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Chinese Physics C 2022年第6期46卷 212-218页

作者：陈超锋陈启博周先荣程奕源崔继伟 H.-J.Schulze Department of Physics East China Normal UniversityShanghai 200241China School of Physics and Optoelectronic Engineering Xidian UniversityXi'an 710071China INFN sezione di Catania Dipartimento di FisicaUniversitádi CataniaVia Santa Sofia 6495123 CataniaItaly

The deformations of multi-Λ hypernuclei corresponding to even-even core nuclei ranging from^(8)Be to^(40)Ca with 2,4,6,and 8 hyperons are studied using the deformed Skyrme-Hartree-Fock approach.It is found that the deformations are reduced when adding 2 or 8 Λ hyperons,but enhanced when adding 4 or 6 Λ hyperons.These differences are attributed to the fact that Λ hyperons are filled gradually into the three deformed p orbits,of which the [110] 1/2^(-)orbit is prolately deformed and the degenerate [101]1/2^(-)and [101]3/2^(-)orbits are oblately deformed.

关键词： deformation even-even nuclei effects of hyperon(s)

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