arXiv: Nuclear Experiment最新文献

{"title":"Exotic Nuclei","authors":"C. Beck","doi":"10.1142/11530","DOIUrl":"https://doi.org/10.1142/11530","url":null,"abstract":"Since the discovery of molecular resonances in $^{12}$C+$^{12}$C in the early sixties a great deal of research work has been undertaken to study alpha-clustering. Our knowledge on physics of nuclear molecules has increased considerably and nuclear clustering remains one of the most fruitful domains of nuclear physics, facing some of the greatest challenges and opportunities in the years ahead. Occurrence of \"exotic\" shapes and Bose-Einstein Condensates in light alpha-cluster nuclei are investigated. Various approaches of superdeformed/hyperdeformed shapes associated with quasimolecular resonant structures are discussed. The astrophysical reaction rate of 12C+12C is extracted from recent fusion measurements at deep subbarrier energies near the Gamov window. Evolution of clustering from stability to the drip-lines is examined.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91235132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of $^{16}$O($gamma$,$alpha$)$^{12}$C measurements on the $^{12}$C($alpha,gamma$)$^{16}$O astrophysical reaction rate","authors":"R. Holt, B. Filippone, S. Pieper","doi":"10.1103/PhysRevC.99.055802","DOIUrl":"https://doi.org/10.1103/PhysRevC.99.055802","url":null,"abstract":"The $^{12}$C($alpha,gamma$)$^{16}$O reaction, an important component of stellar helium burning, plays a key role in nuclear astrophysics. It has direct impact on the evolution and final state of massive stars, while also influencing the elemental abundances resulting from nucleosynthesis in such stars. Providing a reliable estimate for the energy dependence of this reaction at stellar helium burning temperatures has been a major goal for the field. In this work, we study the role of potential new measurements of the inverse reaction, $^{16}$O($gamma,alpha$)$^{12}$C, in reducing the overall uncertainty. A multilevel R-matrix analysis is used to make extrapolations of the astrophysical S factor for this reaction to the stellar energy of 300 keV. The statistical precision of the S-factor extrapolation is determined by performing multiple fits to existing E1 and E2 ground state capture data, including the impact of possible future measurements of the $^{16}$O($gamma,alpha$)$^{12}$C reaction. In particular, we consider a proposed JLab experiment that will make use of a high-intensity low-energy bremsstrahlung beam that impinges on an oxygen-rich single-fluid bubble chamber in order to measure the total cross section for the inverse reaction. The importance of low energy data as well as high precision data is investigated.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88955630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On similarities as a function of system size in heavy ion collisions","authors":"M. Petrovici, A. Lindner, A. Pop","doi":"10.1063/1.5091636","DOIUrl":"https://doi.org/10.1063/1.5091636","url":null,"abstract":"Qualitative and quantitative similarities as a function of the system size in heavy ion collisions from low energy dissipative collisions, collective expansion of compressed baryonic matter up to the geometrical scaling evidenced at the highest energies presently attainable at LHC, are presented.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75936759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Open Charm measurements at the NA61 experiment at CERN SPS","authors":"D. Larsen, A. Merzlaya","doi":"10.1051/epjconf/201819105003","DOIUrl":"https://doi.org/10.1051/epjconf/201819105003","url":null,"abstract":"The strong interactions programme of the NA61/SHINE experiment at CERN SPS has been extended through the use of new silicon Vertex Detector which provides precise measurements of exotic particles with short lifetime. The detector was designed to meet the challenges of primary and secondary vertexes reconstruction at high spatial resolution. An initial version of the Vertex Detector called SAVD (Small Acceptance Vertex Detector) was installed last end of 2016, and data was from Pb+Pb collisions was collected in 2016, for Xe+La in 2017, as well as further Pb+Pb collisions this year. First indication of a D$^0$ peak at SPS energies has been observed. The physics motivation behind the open charm measurements will be discussed, as well as the analysis of collected data on open charm production and the future plans of open charm measurements in NA61/SHINE experiment related to the upgraded version of the vertex detector.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78578805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constraints on the density dependence of the symmetry energy","authors":"J. Lukasik","doi":"10.1393/ncc/i2018-18182-8","DOIUrl":"https://doi.org/10.1393/ncc/i2018-18182-8","url":null,"abstract":"Current status and future experimental plans for constraining the symmetry energy at supra-normal densities are presented. A special emphasis is put on significance of the results obtained by the ASY-EOS Collaboration in a broader astrophysical context, including the recent interpretations of the first LIGO and Virgo GW170817 gravitational wave signal. The plans for a high energy campaign at FAIR using the NeuLAND and the KRAB detectors will be outlined.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73542367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of multi-neutron emission in the $beta$-decay of $^{11}$Li","authors":"F. Delaunay, N. Achouri, A. Algora, M. Assi'e, J. Balibrea, K. Banerjee, C. Bhattacharya, M. Borge, D. Cano-Ott, B. Fern'andez-Dom'inguez, L. Fraile, J. Gibelin, M. Lund, M. Madurga, F. Marqu'es, I. Marroquı́n, T. Mart'inez, E. Mendoza, N. Orr, M. Pârlog, X. Pereira-L'opez, V. Pestel, K. Riisager, C. Santos, M. Sénoville, O. Tengblad, V. Vedia","doi":"10.1393/NCC/I2019-19098-5","DOIUrl":"https://doi.org/10.1393/NCC/I2019-19098-5","url":null,"abstract":"The kinematics of two-neutron emission following the $beta$-decay of $^{11}$Li was investigated for the first time by detecting the two neutrons in coincidence and by measuring their angle and energy. An array of liquid-scintillator neutron detectors was used to reject cosmic-ray and $gamma$-ray backgrounds by pulse-shape discrimination. Cross-talk events in which two detectors are fired by a single neutron were rejected using a filter tested on the $beta$-1n emitter $^9$Li. A large cross-talk rejection rate is obtained ($> 95 %$) over most of the energy range of interest. Application to $^{11}$Li data leads to a significant number of events interpreted as $beta$-2n decay. A discrete neutron line at $approx$ 2 MeV indicates sequential two-neutron emission, possibly from the unbound state at 10.6 MeV excitation energy in $^{11}$Be.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84229877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FAMU: study of the energy dependent transfer rate $Lambda_{mu p rightarrow mu O}$","authors":"F. C. E. Mocchiutti, V. Bonvicini, M. Danailov, E. Furlanetto, K. S. Gadedjisso-Tossou, D. Guffanti, C. Pizzolotto, A. Rachevski, L. Stoychev, E. Vallazza, G. Zampa, J. Niemela, K. Ishida, A. Adamczak, G. Baccolo, R. Benocci, R. Bertoni, M. Bonesini, F. Chignoli, M. Clemenza, A. Curioni, V. Maggi, R. Mazza, M. Moretti, M. Nastasi, E. Previtali, Dinyo Bakalov, P. Danev, M. Stoilov, G. Baldazzi, R. Campana, I. D'Antone, M. Furini, F. Fuschino, C. Labanti, A. Margotti, S. Meneghini, G. Morgante, L. Rignanese, P. L. Rossi, M. Zuffa, T. Cervi, A. Bari, A. Menegolli, C. Vecchi, R. Nardo, M. Rossella, A. Tomaselli, L. Colace, M. Vincenzi, A. Iaciofano, F. Somma, L. Tortora, R. Ramponi, A. G. M. I. O. Physics, Sezione di Trieste, 2. viaA.Valerio, 34127 Trieste, Italy., Elettra-Sincrotrone Trieste S.C.p.A., SS14, Km 163.5, 34149 Basovizza, Trieste, Mathematics, I. Department, Udine University, via delle Scienze 206, Udine, The Abdus Salam International Centre for Theoretical Physics, 11 StradaCostiera, Laboratoire","doi":"10.1088/1742-6596/1138/1/012017","DOIUrl":"https://doi.org/10.1088/1742-6596/1138/1/012017","url":null,"abstract":"The main goal of the FAMU experiment is the measurement of the hyperfine splitting (hfs) in the 1S state of muonic hydrogen $Delta E_{hfs}(mu^-p)1S$. The physical process behind this experiment is the following: $mu p$ are formed in a mixture of hydrogen and a higher-Z gas. When absorbing a photon at resonance-energy $Delta E_{hfs}approx0.182$~eV, in subsequent collisions with the surrounding $H_2$ molecules, the $mu p$ is quickly de-excited and accelerated by $sim2/3$ of the excitation energy. The observable is the time distribution of the K-lines X-rays emitted from the $mu Z$ formed by muon transfer $(mu p) +Z rightarrow (mu Z)^*+p$, a reaction whose rate depends on the $mu p$ kinetic energy. The maximal response, to the tuned laser wavelength, of the time distribution of X-ray from K-lines of the $(mu Z)^*$ cascade indicate the resonance. During the preparatory phase of the FAMU experiment, several measurements have been performed both to validate the methodology and to prepare the best configuration of target and detectors for the spectroscopic measurement. We present here the crucial study of the energy dependence of the transfer rate from muonic hydrogen to oxygen ($Lambda_{mu p rightarrow mu O}$), precisely measured for the first time.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81109625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Status of the Chiral Magnetic Effect Search in Relativistic Heavy-Ion Collisions","authors":"Jie-Cheng Zhao, Z. Tu, Fuqiang Wang","doi":"10.11804/NuclPhysRev.35.03.225","DOIUrl":"https://doi.org/10.11804/NuclPhysRev.35.03.225","url":null,"abstract":"Quark interactions with topological gluon fields in QCD can yield local $mathcal{P}$ and $mathcal{CP}$ violations which could explain the matter-antimatter asymmetry in our universe. Effects of $mathcal{P}$ and $mathcal{CP}$ violations can result in charge separation under a strong magnetic field, a phenomenon called the chiral magnetic effect (CME). Experimental measurements of the CME-induced charge separation in heavy-ion collisions are dominated by physics backgrounds. Major theoretical and experimental efforts have been devoted to eliminating or reducing those backgrounds. We review the current status of these efforts in the search for the CME in heavy-ion collisions.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83038106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Search for the Chiral Magnetic Effect in Relativistic Heavy-Ion Collisions","authors":"Jie-Cheng Zhao","doi":"10.1142/S0217751X18300107","DOIUrl":"https://doi.org/10.1142/S0217751X18300107","url":null,"abstract":"Relativistic heavy-ion collisions provide an ideal environment to study the emergent phenomena in quantum chromodynamics (QCD). The chiral magnetic effect (CME) is one of the most interesting, arising from the topological charge fluctuations of QCD vacua, immersed in a strong magnetic field. Since the first measurement nearly a decade ago of the possibly CME-induced charge correlation, extensive studies have been devoted to background contributions to those measurements. Many new ideas and techniques have been developed to reduce or eliminate the backgrounds. This article reviews these developments and the overall progress in the search for the CME.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75510209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COHERENT Collaboration data release from the first observation of coherent elastic neutrino-nucleus scattering","authors":"D. Akimov, J. Collar, J. Daughhetee, R. Varner, A. Khromov, J. Yoo, J. Newby, A. Galindo-Uribarri, D. Reyna, M. Kaemingk, S. Klein, C. Cuesta, H. Ray, E. Iverson, M. Kremer, H. Moreno, M. Hai, Peibo An, J. Orrell, M. Cervantes, C. Awe, C. Overman, D. Salvat, W. Lu, D. Rudik, M. Febbraro, G. Sinev, B. Suh, S. Ki, G. Perumpilly, A. Burenkov, R. Cooper, A. Etenko, R. Rapp, A. Zderic, S. Elliott, Blackston, Y. Efremenko, R. Cooper, P. Barbeau, D. Hornback, C. H. Yu, K. Scholberg, A. Kovalenko, A. Zawada, C. Leadbetter, S. Penttila, S. Suchyta, R. Tayloe, R. Thornton, L. Fabris, P. Naumov, L. Kaufman, B. Scholz, K. Miller, B. Cabrera-Palmer, S. Hedges, G. Rich, A. Eberhardt, P. Mueller, D. Radford, M. Heath, T. Hossbach, V. Belov, J. Zettlemoyer, M. D. V. Coello, Z. Wan, A. Shakirov, I. Tolstukhin, D. Markoff, N. Fields, W. Snow, A. Kumpan, A. Konovalov, V. Sosnovtsev, A. Bolozdynya, K. Mann, M. D’Onofrio, Z. Fu, J. Vanderwerp, D. Parno, C. Virtue, J. Albert, A. Brown, L. Li, J. Detwiler, D. Rimal, W. Fox, M. ","doi":"10.5281/zenodo.1228631","DOIUrl":"https://doi.org/10.5281/zenodo.1228631","url":null,"abstract":"This release includes data and information necessary to perform independent analyses of the COHERENT result presented in Akimov et al., arXiv:1708.01294 [nucl-ex]. Data is shared in a binned, text-based format, including both \"signal\" and \"background\" regions, so that counts and associated uncertainties can be quantitatively calculated for the purpose of separate analyses. This document describes the included information and its format, offering some guidance on use of the data. Accompanying code examples show basic interaction with the data using Python.","PeriodicalId":8464,"journal":{"name":"arXiv: Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83288005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}