arXiv - PHYS - Nuclear Experiment最新文献

{"title":"Search for the Chiral Magnetic Effect using Sliding Dumbbell Method in Isobar Collisions ($^{96}_{44}Ru$+$^{96}_{44}Ru$ and $^{96}_{40}Zr$+$^{96}_{40}Zr$) at RHIC","authors":"Jagbir Singh","doi":"arxiv-2406.06503","DOIUrl":"https://doi.org/arxiv-2406.06503","url":null,"abstract":"Experiments conducted in the last decade to search for the Chiral Magnetic\u0000Effect (CME) in heavy-ion collisions have been inconclusive. The Isobar program\u0000at RHIC was undertaken to address this problem. Also, a new approach known as\u0000the Sliding Dumbbell Method (SDM) has been developed to study the CME. This\u0000method searches for the back-to-back charge separation on an event-by-event\u0000basis.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507888","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":"Observation and spectroscopy of proton-unbound nucleus $^{21}$Al","authors":"D. Kostyleva, X. -D. Xu, I. Mukha, L. Acosta, M. Bajzek, E. Casarejos, A. A. Ciemny, D. Cortina-Gil, W. Dominik, J. A. Dueñas, J. M. Espino, A. Estradé, F. Farinon, A. Fomichev, H. Geissel, J. Gómez-Camacho, A. Gorshkov, L. V. Grigorenko, Z. Janas, G. Kamiński, O. Kiselev, R. Knöbel, A. A. Korsheninnikov, S. Krupko, M. Kuich, N. Kurz, Yu. A. Litvinov, G. Marquinez-Durán, I. Martel, C. Mazzocchi, E. Yu. Nikolskii, C. Nociforo, A. K. Ordúz, M. Pfützner, S. Pietri, M. Pomorski, A. Prochazka, C. Rodríguez-Tajes, S. Rymzhanova, A. M. Sánchez-Benítez, C. Scheidenberger, H. Simon, B. Sitar, R. Slepnev, M. Stanoiu, P. Strmen, K. Sümmerer, I. Szarka, M. Takechi, Y. K. Tanaka, H. Weick, J. S. Winfield, P. J. Woods, M. V. Zhukov","doi":"arxiv-2406.04771","DOIUrl":"https://doi.org/arxiv-2406.04771","url":null,"abstract":"We report on the observation of previously-unknown isotope $^{21}$Al, the\u0000first unbound aluminum isotope located beyond the proton dripline. The\u0000$^{21}$Al nucleus decays by one-proton (1p) emission, and its in-flight decays\u0000were detected by tracking trajectories of all decay products with micro-strip\u0000silicon detectors. The 1p-emission processes were studied by analyses of the\u0000measured angular correlations of decay products $^{20}$Mg+p. The 1p-decay\u0000energies of ground and low-lying excited states of $^{21}$Al, its mass excess\u0000and proton separation energy value $S_p$=$-1.1(1)$ MeV were determined.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507889","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":"Nuclear Data to Quantify Urca Cooling in Accreting Neutron Stars","authors":"Rahul Jain","doi":"arxiv-2406.02634","DOIUrl":"https://doi.org/arxiv-2406.02634","url":null,"abstract":"Neutron stars in Low Mass X-ray Binaries (LMXBs) can accrete matter onto\u0000their surface from the companion star. Transiently accreting neutron stars go\u0000through alternating phases of active accretion outbursts and quiescence. X-ray\u0000observations during the quiescence phase show a drop in X-ray luminosity with\u0000the time in quiescence. This is also inferred as the drop in surface\u0000temperature or the cooling of accreting neutron stars in quiescence. Analyzing\u0000these cooling curves reveals a great deal of information about the structure\u0000and composition of neutron stars. However, model-observation comparisons of\u0000such cooling curves are challenging - partly due to observational\u0000uncertainties, and partly due to incomplete knowledge of heating mechanisms\u0000during accretion outbursts. This situation is further exacerbated by the recent\u0000discovery of Urca cooling in the neutron star crust. These are cycles that\u0000alternate between electron-capture and beta-decay to produce a large flux of\u0000neutrinos and anti-neutrinos. These freely stream out of the star and carry\u0000energy with them, essentially cooling the neutron star crust without changing\u0000the composition. As a result, it is necessary to accurately quantify the\u0000strength of Urca cooling to constrain the heat sources in neutron star crusts\u0000and facilitate better model-observation comparisons of the cooling curves.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141521033","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":"Femtoscopy at NA61/SHINE using symmetric Lévy sources in central $^{40}$Ar+$^{45}$Sc from 40$A$ GeV/$c$ to 150$A$ GeV/$c$","authors":"Barnabas Porfyfor the NA61/SHINE Collaboration","doi":"arxiv-2406.02242","DOIUrl":"https://doi.org/arxiv-2406.02242","url":null,"abstract":"In the recent decades of high energy physics research, it was demonstrated\u0000that strongly interacting quark-gluon plasma (sQGP) is created in\u0000ultra-relativistic nucleus-nucleus collisions. Investigation and understanding\u0000of properties of the hadronic matter is among the important goals of NA61/SHINE\u0000collaboration at CERN SPS. Mapping of the phase diagram is achieved by varying\u0000the collision energy (5 GeV $<sqrt{s_{textrm{NN}}}<$17 GeV) and by changing\u0000the collision system (p+p, p+Pb, Be+Be, Ar+Sc, Xe+La, Pb+Pb). We report on the\u0000measurement of femtoscopic correlations in intermediate system at intermediate\u0000SPS energies. Interpreting the results of measurements within the symmetric\u0000L'evy source formalism, we discuss the values of L'evy source parameters as a\u0000function of average pair transverse mass. One of the physical parameters is\u0000particularly important, the L'evy exponent $alpha$, which describes the shape\u0000of the source and may be related to the critical exponent $eta$ in the\u0000proximity of the critical point. Therefore, measuring it may shed light on the\u0000location of the critical endpoint of the QCD phase diagram.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141254609","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":"$K^+Λ(1520)$ photoproduction at forward angles near threshold with the BGOOD experiment","authors":"E. O. Rosanowski, T. C. Jude, S. Alef, A. J. Clara Figueiredo, R. Di Salvo, D. Elsner, A. Fantini, O. Freyermuth, F. Frommberger, F. Ghio, J. Groß, K. Kohl, P. Levi Sandri, G. Mandaglio, R. Messi, D. Moricciani, P. Pedroni, B. -E. Reitz, M. Romaniuk, G. Scheluchin, H. Schmieden, A. Sonnenschein","doi":"arxiv-2406.01121","DOIUrl":"https://doi.org/arxiv-2406.01121","url":null,"abstract":"The differential cross section for $gamma prightarrow K^+Lambda(1520)$ was\u0000measured from threshold to a centre-of-mass energy of 2090,MeV at forward\u0000angles at the BGOOD experiment. The high statistical precision and resolution\u0000in centre-of-mass energy and angle allows a detailed characterisation of this\u0000low-momentum transfer kinematic region. The data agree with a previous LEPS\u0000measurement and support effective Lagrangian models that indicate that the\u0000contact term dominates the cross section near threshold.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141254389","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":"Remeasuring the $γ$-decay branching ratio of the Hoyle state","authors":"W. Paulsen, K. C. W. Li, S. Siem, V. W. Ingeberg, A. C. Larsen, T. K. Eriksen, H. C. Berg, M. M. Bjørøen, B. J. Coombes, J. T. H. Dowie, F. W. Furmyr, F. L. B. Garrote, D. Gjestvang, A. Görgen, T. Kibédi, M. Markova, V. Modamio, E. Sahin, A. E Stuchbery, G. M. Tveten, V. M. Valsdòttir","doi":"arxiv-2406.00397","DOIUrl":"https://doi.org/arxiv-2406.00397","url":null,"abstract":"The radiative branching ratio of the Hoyle state is crucial to estimate the\u0000triple-$alpha$ reaction rate in stellar environments at medium temperatures.\u0000Knowledge of the $gamma$-decay channel is critical as this is the dominant\u0000radiative decay channel for the Hoyle state. A recent study by Kib'edi et al.\u0000[Phys. Rev. Lett. 125, 182701 (2020)] has challenged our understanding of this\u0000astrophysically significant branching ratio and its constraints. The objective\u0000of this work was to perform a new measurement of the $gamma$-decay branching\u0000ratio of the Hoyle state to deduce the radiative branching ratio of the Hoyle\u0000state. An additional objective was to independently verify aspects of the\u0000aforementioned measurement conducted by Kib'edi et al. For the main experiment\u0000of this work, the Hoyle state was populated by the $^{12}textrm{C}(p,p')$\u0000reaction at 10.8 MeV at the Oslo Cyclotron Laboratory. The $gamma$-decay\u0000branching ratio was deduced through triple-coincidence events, each consisting\u0000of a proton ejectile corresponding to the Hoyle state, and the subsequent\u0000$gamma$-ray cascade. In the main experiment of this work, a $gamma$-decay\u0000branching ratio of the Hoyle state of $Gamma_{gamma}/Gamma=4.0(4)times\u000010^{-4}$ was determined, yielding a corresponding radiative branching ratio of\u0000$Gamma_{textrm{rad}}/Gamma=4.1(4) times 10^{-4}$, which is in agreement\u0000with several recent studies, as well as the previously adopted ENSDF average of\u0000$Gamma_{textrm{rad}}/Gamma=4.16(11)times 10^{-4}$. Aspects of the analysis\u0000performed by Kib'edi et al. were verified in this work and the source of\u0000discrepancy between the results of this work and that of Kib'edi et al. could\u0000not be determined. Further independent and innovative studies for the radiative\u0000width of the Hoyle state will substantiate whether the discrepant result by\u0000Kib'edi et al. should be excluded from future evaluations.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141259736","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":"Recent Highlights from STAR BES Phase II","authors":"Dylan Nefffor the STAR Collaboration","doi":"arxiv-2405.20928","DOIUrl":"https://doi.org/arxiv-2405.20928","url":null,"abstract":"The second phase of the RHIC Beam Energy Scan (BES-II) was conducted between\u00002019 and 2021. High statistics data was collected by the STAR experiment for\u0000Au+Au collisions at $sqrt{s_{NN}}$ from 7.7 to 27 GeV in collider mode and\u0000from 3 to 13.7 GeV in fixed target mode. A selection of results from the\u0000various BES-II analyses are presented here to showcase the wide range of\u0000physics accessible.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141254399","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":"Probing the nature of the QCD phase transition with higher-order net-proton number fluctuation and local parton density fluctuation measurements at RHIC-STAR","authors":"Dylan Nefffor the STAR Collaboration","doi":"arxiv-2405.20929","DOIUrl":"https://doi.org/arxiv-2405.20929","url":null,"abstract":"The moments of proton and net-proton multiplicity distributions are\u0000observables expected to be sensitive to the QCD critical point and the nature\u0000of the QCD phase transition from QGP to hadron gas. Hyper-order cumulants are\u0000measured in wide centrality bins in STAR BES-I data and found to be\u0000qualitatively consistent with trends predicted by lattice QCD which finds a\u0000cross-over phase transition at low $mu_text{B}$. Data collected at\u0000$sqrt{s_{NN}}=3$ GeV in BES-II exhibit trends opposite of those observed in\u0000higher energy collisions which may suggest the dominance of hadronic\u0000interactions at this energy. The variance of proton multiplicity distributions\u0000in azimuthal partitions is measured to search for signals of clustering\u0000indicative of a first-order phase transition. A strong dependence on the event\u0000multiplicity is observed. This dependence is independent of energy in AMPT\u0000while in STAR data a significant trend with energy is observed.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141254606","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":"Measurement of ${}_Λ^{3}mathrm{H}$ production in Pb-Pb collisions at $sqrt{s_{mathrm{NN}}}$ = 5.02 TeV","authors":"ALICE Collaboration","doi":"arxiv-2405.19839","DOIUrl":"https://doi.org/arxiv-2405.19839","url":null,"abstract":"The first measurement of $_{Lambda}^{3}mathrm{H}$ and $^3_\u0000{overline{Lambda}}overline{mathrm{H}}$ differential production with respect\u0000to transverse momentum and centrality in Pb$-$Pb collisions at\u0000$sqrt{s_{mathrm{NN}}}=5.02$~TeV is presented. The $_{Lambda}^{3}mathrm{H}$\u0000has been reconstructed via its two-charged-body decay channel, i.e.,\u0000$_{Lambda}^{3}mathrm{H} rightarrow {}^{3}mathrm{He} + pi^{-}$. A\u0000Blast-Wave model fit of the $p_{rm T}$-differential spectra of all nuclear\u0000species measured by the ALICE collaboration suggests that the\u0000$_{Lambda}^{3}mathrm{H}$ kinetic freeze-out surface is consistent with that\u0000of other nuclei. The ratio between the integrated yields of\u0000$_{Lambda}^{3}mathrm{H}$ and $^3mathrm{He}$ is compared to predictions from\u0000the statistical hadronisation model and the coalescence model, with the latter\u0000being favoured by the presented measurements.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141191916","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":"Initial measurement of reactor antineutrino oscillation at SNO+","authors":"SNO+ Collaboration, :, A. Allega, M. R. Anderson, S. Andringa, M. Askins, D. J. Auty, A. Bacon, J. Baker, F. Barão, N. Barros, R. Bayes, E. W. Beier, T. S. Bezerra, A. Bialek, S. D. Biller, E. Blucher, E. Caden, E. J. Callaghan, M. Chen, S. Cheng, B. Cleveland, D. Cookman, J. Corning, M. A. Cox, R. Dehghani, J. Deloye, M. M. Depatie, F. Di Lodovico, C. Dima, J. Dittmer, K. H. Dixon, M. S. Esmaeilian, E. Falk, N. Fatemighomi, R. Ford, A. Gaur, O. I. González-Reina, D. Gooding, C. Grant, J. Grove, S. Hall, A. L. Hallin, D. Hallman, W. J. Heintzelman, R. L. Helmer, C. Hewitt, V. Howard, B. Hreljac, J. Hu, P. Huang, R. Hunt-Stokes, S. M. A. Hussain, A. S. Inácio, C. J. Jillings, S. Kaluzienski, T. Kaptanoglu, H. Khan, J. Kladnik, J. R. Klein, L. L. Kormos, B. Krar, C. Kraus, C. B. Krauss, T. Kroupová, C. Lake, L. Lebanowski, C. Lefebvre, V. Lozza, M. Luo, A. Maio, S. Manecki, J. Maneira, R. D. Martin, N. McCauley, A. B. McDonald, C. Mills, G. Milton, A. Molina Colina, D. Morris, I. Morton-Blake, M. Mubasher, S. Naugle, L. J. Nolan, H. M. O'Keeffe, G. D. Orebi Gann, J. Page, K. Paleshi, W. Parker, J. Paton, S. J. M. Peeters, L. Pickard, B. Quenallata, P. Ravi, A. Reichold, S. Riccetto, J. Rose, R. Rosero, I. Semenec, J. Simms, P. Skensved, M. Smiley, J. Smith, R. Svoboda, B. Tam, J. Tseng, E. Vázquez-Jáuregui, J. G. C. Veinot, C. J. Virtue, M. Ward, J. J. Weigand, J. R. Wilson, J. D. Wilson, A. Wright, S. Yang, M. Yeh, Z. Ye, S. Yu, Y. Zhang, K. Zuber, A. Zummo","doi":"arxiv-2405.19700","DOIUrl":"https://doi.org/arxiv-2405.19700","url":null,"abstract":"The SNO+ collaboration reports its first spectral analysis of long-baseline\u0000reactor antineutrino oscillation using 114 tonne-years of data. Fitting the\u0000neutrino oscillation probability to the observed energy spectrum yields\u0000constraints on the neutrino mass-squared difference $Delta m^2_{21}$. In the\u0000ranges allowed by previous measurements, the best-fit $Delta m^2_{21}$ is\u0000(8.85$^{+1.10}_{-1.33}$) $times$ 10$^{-5}$ eV$^2$. This measurement is\u0000continuing in the next phases of SNO+ and is expected to surpass the present\u0000global precision on $Delta m^2_{21}$ with about three years of data.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141191708","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}