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Journal of Modern Physics 2014年第3期5卷 99-102页

作者： Euro Spallucci Claudio Verzegnassi dipartimento di Fisica Sezione Teorica Università di Trieste and INFN Sezione di Trieste Italy

We compute in a theoretical quantum field theory framework the effects that a classic environment will have on an elementary one-fermion state, assumed for simplicity to be that of one electron, in the presence of a magnetic field. We consider its total energy and its spin angular momentum as relevant observables of the state. We show that the changes of these quantities produced by the combined environmental and magnetic effects can be expressed in a simple and compact form. We obtain expressions that only depend on the values of the external environment and magnetic fields, and on the special spin features of the free fermion state. We call these effects “fermion epigenetics” and try to motivate this definition discussing possible relevant analogies with the corresponding medical treatment of epigenetics in organic cells.

关键词： Epigenetics Quantum Field Theory dirac Equation

Angular Momentum Minimal Magnetization of an Elementary Quantum Fermion System

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Journal of Modern Physics 2013年第5期4卷 638-643页

作者： C. Verzegnassi dipartimento di Fisica Università di Trieste INFN Sezione di Trieste Italy

I consider, in a Quantum Field Theory theoretical approach, the effects of an electromagnetic field on the components of the total angular momentum of an elementary fermion system, assuming the “minimal” form of the relative interaction. When the electromagnetic field can be treated as a classical one, these effects are particularly simple to be computed and exhibit a number of very general characteristic features in the case of a constant magnetic field. A qualitative possible analogy with similar features of an elementary organic system is finally proposed.

关键词： Organic

A Quantum Field Theory Toy-Model for Magnetic Epigenetic

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Journal of Modern Physics 2013年第8期4卷 1133-1138页

作者： Fabio Burigana Euro Spallucci Claudio Verzegnassi AMEC (Association for Medicine and Complexity) Trieste Italy dipartimento di Fisica Sezione Teorica Università di Trieste and INFN Trieste Italy dipartimento di Fisica Sezione Teorica Università di Trieste and INFN Trieste Udine Italy

We consider the effects that a magnetic field has on the observable properties of an elementary one-fermion state, assumed for simplicity to be that of one electron. We show that for a weak intensity of the field these effects can be very simply computed in a quantum field theory theoretical framework, assuming the minimal form of the electromagnetic interaction and the validity of the dirac equation. The effects proceed via preliminary, magnetic field induced, modification of the four components of the spinor field. These generate consequent modifications of the various observable properties of the fermion, which can always be simply expressed in terms of the four spinor field components. A few general features of the various effects are discussed, and a number of possible analogies with the fascinating medical description of the epigenetic process for an organic cell are finally proposed.

关键词： Epigenetics Quantum Field Theory dirac Equation

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

Competition between fusion-evaporation and multifragmentation in central collisions in ^(58)Ni+^(48)Ca at 25A MeV

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Nuclear Science and Techniques 2013年第5期24卷 82-88页

作者： FRANCALANZA L ABBONDANNO U AMORINI F BARLINI S BINI M BOUGAULT R BRUNO M CARDELLA G CASINI G AGOSTINO M D' De FILIPPO V De SANCTIS J GERACI E GIUSSANI A GRAMEGNA F GUIOT B KRAVCHUK V La GUIDARA E LANZALONE G Le NEINDRE N MAIOLINO C MARINI P MORELLI L OLMI A PAGANO A PAPA M PIANTELLI S PIRRONE S POLITI G POGGI G PORTO F RUSSOTTO P RIZZO F VANNINI G VANNUCCI L INFN Laboratori Nazionali del Sud-LNS Catania 95123Italy dipartimento di Fisica Universitàdi Catania I-95129Italy INFN Sezione di Trieste Trieste I-34127Italy dipartimento di Fisica Universitàdi FirenzeINFN Sezione di Firenze 1-50139Italy LPC Caen IN2P3-CNRS/ENSICAEN and UniversitéF-14050 Caen cedex 5-140France dipartimento di Fisica Universitàdi Bologna and INFN Sezione di Bologna 4-50121Italy INFN sezione di Catania I-95129 Italy INFN sezione di Firenze I-50139 Italy dipartimento di Fisica Universitàdi Milano and INFN Sezione di Milano1-20126Italy INFN Laboratori Nazionali di Legnaro 1-35020 Italy Centro Siciliano di Fisica Nucleare e Struttura della Materia Catania 1-95129Italy UniversitàKore Enna 1-94100Italy

The experimental data concerning the58Ni+48Ca reaction at Elab(Ni)=25A MeV,collected by using the CHIMERA 4π device,have been analyzed in order to investigate the competition among different reaction mechanisms for central collisions in the Fermi energy domain.As a main criterion for centrality selection we have chosen the flow angle(flow) method,making an event-by-event analysis that considers the shape of events,as it is determined by the eigenvectors of the experimental kinetic-energy tensor.For the selected central events(flow >60°) some global variables,good to characterize the pattern of central collisions have been constructed.The main features of the reaction products were explored by using different constraints on some of the relevant observables,like mass and velocity distributions and their correlations.Much emphasis was devoted,for central collisions,to the competition between fusion-evaporation processes with subsequent identification of a heavy residue and a possible multifragmentation mechanism of a well defined(if any) transient nuclear system.Dynamical evolution of the system and pre-equilibrium emission were taken into account by simulating the reactions in the framework of transport theories.different approaches have been envisaged(dynamical stochastic BNV calculations + sequential SIMON code,QMD,CoMD,etc.).Preliminary comparison of the experimental data with BNV calculations shows reasonable agreement with the assumption of sequential multifragmentation emission in the mass region of IMFs close to the heavy residues.Possible deviations from sequential processes were found for those IMFs in the region of masses intermediate between the mass of heavy residues and the mass of light IMFs.Further simulations are in progress.The experimental analysis will be enriched also by information obtained inspecting the IMF-IMF correlation function,in order to elucidated the nature of space-time decay property of the emitting source associated with events having the largest IMF multiplicity.

关键词：多重碎裂中心碰撞蒸发过程 MeV 竞争熔合国际货币基金组织事件分析

上海光源X射线成像实验站相位衬度CT初步结果

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核技术 2009年第4期32卷 241-245页

作者：陈荣昌杜国浩谢红兰邓彪朱佩平佟亚军胡雯薛艳玲陈灿任玉琦周光照王玉丹肖体乔徐洪杰中国科学院上海应用物理研究所上海201800 dipartimento di Fisica Universita di Trieste e INFNSezione di Trieste 中国科学院高能物理研究所北京100049

X射线相位衬度CT能获得样品内部结构的边缘增强图像,可观察到传统X射线吸收CT无法观察到的生物软组织内部微细结构,具有巨大发展潜力。经初步调试,上海光源X射线成像实验站的8-72.5keV单色X射线输出已能用于实验研究。本文在X射线成像... 详细信息

X射线相位衬度CT能获得样品内部结构的边缘增强图像,可观察到传统X射线吸收CT无法观察到的生物软组织内部微细结构,具有巨大发展潜力。经初步调试,上海光源X射线成像实验站的8-72.5keV单色X射线输出已能用于实验研究。本文在X射线成像实验站上开展生物样品(蝗虫)同轴X射线相位衬度CT研究,获得蝗虫样品的切片重构图像和三维重建图像。结果图像中,蝗虫样品的翅膀、表面纹理和内部组织分布情况清晰可见。

关键词： CT 相位衬度成像 X射线同步辐射

基于玻恩近似相位恢复的X射线显微CT实验研究

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光学学报 2010年第4期30卷 1106-1111页

作者：陈荣昌谢红兰杜国浩邓彪朱佩平佟亚军王玉丹肖体乔中国科学院上海应用物理研究所上海201800 中国科学院研究生院北京100049 dipartimento di Fisica Universita di Trieste e INFNSezione di TriesteItaly 中国科学院高能物理研究所北京100049

结合同轴X射线相位衬度成像(XPCI)中的Born近似相位恢复法和CT技术,实现了基于单一物像距同轴X射线相位衬度CT(IL-XPCT)投影图像的相位恢复切片重构方法。利用上海光源X射线成像及生物医学应用光束线站的单色光开展模型和生物样品(蝗虫)... 详细信息

结合同轴X射线相位衬度成像(XPCI)中的Born近似相位恢复法和CT技术,实现了基于单一物像距同轴X射线相位衬度CT(IL-XPCT)投影图像的相位恢复切片重构方法。利用上海光源X射线成像及生物医学应用光束线站的单色光开展模型和生物样品(蝗虫)IL-XPCT研究。对比显示,进行相位恢复后,能获得更好的IL-XPCT重构切片和三维重建图像。实验结果表明,本方法具有用于生物活体样品三维无损成像研究的潜力。

关键词：医用光学 X射线显微CT 相位恢复 Born近似

Exploring fermionic multiplet dark matter through precision measurements at the CEPC

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Chinese Physics C 2022年第9期46卷 159-172页

作者：高林青毕效军王金伟向仟飞殷鹏飞 Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Scuola Internazionale Superiore di Studi Avanzati(SISSA) via Bonomea 26534136 TriesteItaly INFN Sezione di Triestevia Valerio 234127 TriesteItaly Institute for Fundamental Physics of the Universe(IFPU) via Beirut 234151 TriesteItaly Center for High Energy Physics Peking UniversityBeijing 100871China

New physics could be explored through loop effects using the precision measurements at the Circular Electron Positron Collider(CEPC)owing to its clean collision environment and high luminosity.In this paper,we focus on two dark matter models that involve additional electroweak fermionic multiplets.We calculate their one-loop corrections in five processes,i.e.,e^(+)e^(-)→μ^(+)μ^(-),Zh,W^(+)W^(-),ZZ,and,Zγ,and investigate the corresponding signatures at the CEPC with the projected sensitivity.We observe that the detectable parameter regions of these processes are complementary.The combined analysis shows that the mass of dark matter m_(χ^(0)_(1))in these two models can be probed up to-150GeV and-450GeV,respectively,at a 95%confidence level.

关键词： CEPC dark matter loop correction

The density profiles of dark matter halos in spiral galaxies

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Natural Science 2012年第5期4卷 265-270页

作者： Gianluca Castignani Noemi Frusciante Daniele Vernieri Paolo Salucci INFN Istituto Nazionale di Fisica Nucleare Sezione di Trieste Trieste Italy NFN Istituto Nazionale di Fisica Nucleare Sezione di Trieste Trieste Italy SISSA-ISAS International School for Advanced Studies SISSA-ISAS International School for Advanced Studies Trieste Italy

In spiral galaxies, we explain their non-Keplerian rotation curves (RCs) by means of a non-luminous component embedding their stellar-gaseous disks. Understanding the detailed properties of this component (labelled Dark Matter, DM) is one of the most pressing issues of Cosmology. We investigate the recent relationship (claimed by Walker et al. 2010, hereafter W + 10) between r, the galaxy radial coordinate, and Vh(r), the dark halo contribution to the circular velocity at r, 1) in the framework of the Universal Rotation Curve (URC) paradigm and directly 2) by means of the kinematics of a large sample of DM dominated spirals. We find a general agreement between the W + 10 claim, the distribution of DM emerging from the URC and that inferred in the (low luminosity) objects of our sample. We show that such a phenomenology, linking the spiral’s luminosity, radii and circular velocities, implies an evident inconsistency with (naive) predictions in the Λ Cold Dark Matter (ΛCDM) scenario.

关键词： Galaxies Spiral Kinematics and Dynamics Dark Matter

基于THGEM的单光子探测的阳离子回流研究

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基于THGEM的单光子探测的阳离子回流研究