Journal of Physics G最新文献_第8页

Breaking μ − τ symmetry of tri-bimaximal mixing 三双极大混合的μ−τ对称性破缺

Journal of Physics G Pub Date : 2020-11-02 DOI: 10.1088/1361-6471/abc6e8

Kanwaljeet S Channey, Sanjeev Kumar

引用次数: 1

Pygmy dipole resonance in the well-deformed even–even 152–162Gd 均匀变形的偶极子共振在152-162Gd

Journal of Physics G Pub Date : 2020-11-01 DOI: 10.1088/1361-6471/abaca0

E. Guliyev, H. Quliyev, A. Kuliev

引用次数: 8

A search for neutron magicity in the isotopic series of Z = 122, 128 superheavy nuclei 在Z = 122,128超重核的同位素序列中寻找中子的魔力

Journal of Physics G Pub Date : 2020-11-01 DOI: 10.1088/1361-6471/ab8914

Tasleem A. Siddiqui, A. Quddus, S. Ahmad, S. Patra

引用次数: 7

Implication of $bto ctau {overline{nu }}_{tau }$ flavor anomalies on ${B}_{s}to {D}_{s}^{{ast}}tau {overline{nu }}_{tau }$ decay observables $bto ctau {overline{nu }}_{tau }$风味异常对${B}_{s}to {D}_{s}^{{ast}}tau {overline{nu }}_{tau }$衰变观测值的影响

Journal of Physics G Pub Date : 2020-11-01 DOI: 10.1088/1361-6471/ABA422

N. Das, Rupak Dutta

引用次数: 5

Initialization effects of nucleon profile on the π yields in heavy-ion collisions at medium energies 中能重离子碰撞中核子轮廓对π产率的初始化效应

Journal of Physics G Pub Date : 2020-10-13 DOI: 10.1088/1361-6471/ac1392

Zu-Xing Yang, N. Michel, Xiao-Hua Fan, W. Zuo

{"title":"Initialization effects of nucleon profile on the π yields in heavy-ion collisions at medium energies","authors":"Zu-Xing Yang, N. Michel, Xiao-Hua Fan, W. Zuo","doi":"10.1088/1361-6471/ac1392","DOIUrl":"https://doi.org/10.1088/1361-6471/ac1392","url":null,"abstract":"We study a problem of $pi$ production in heavy ion collisions in the context of the Isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport model. We generated nucleon densities using two different models, the Skyrme-Hartree-Fock (SHF) model and configuration interaction shell model (SM). Indeed, inter-nucleon correlations are explicitly taken into account in SM, while they are averaged in the SHF model. As an application of our theoretical frameworks, we calculated the $pi^{-}$ and $pi^{+}$ yields in collisions of nuclei with $A = 30-40$ nucleons. We used different harmonic oscillator lengths $b_{HO}$ to generate the harmonic oscillator basis for SM in order to study both theoretical and experimental cases. It is found that SM framework with $b_{HO}$ = 2.5 fm and SHF can be distinguished by the yield of $pi$ mesons, in this case the density distribution calculated by the shell model produces more $pi$ in the collision. In comparison, SM with $b_{HO}$ = 2.0 fm is distinguished from SHF by the double $pi^-/pi^+$ ratios with different large impact parameters, from which one can find that the double $pi^-/pi^+$ ratios of SM change smoother and are less than those of SHF.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84793227","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}

引用次数: 3

Effect of thousands of inelastic couplings on the elastic scattering channel 数千个非弹性耦合对弹性散射通道的影响

Journal of Physics G Pub Date : 2020-10-01 DOI: 10.1088/1361-6471/aba424

L. C. Chamon, L. Gasques, J. Zamora

引用次数: 2

Recent advances in the quantification of uncertainties in reaction theory 反应理论中不确定度量化的最新进展

Journal of Physics G Pub Date : 2020-09-21 DOI: 10.1088/1361-6471/abba72

A. Lovell, F. Nunes, M. Catacora-Rios, G. King

{"title":"Recent advances in the quantification of uncertainties in reaction theory","authors":"A. Lovell, F. Nunes, M. Catacora-Rios, G. King","doi":"10.1088/1361-6471/abba72","DOIUrl":"https://doi.org/10.1088/1361-6471/abba72","url":null,"abstract":"Uncertainty quantification has become increasingly more prominent in nuclear physics over the past several years. In few-body reaction theory, there are four main sources that contribute to the uncertainties in the calculated observables: the effective potentials, approximations made to the few-body problem, structure functions, and degrees of freedom left out of the model space. In this work, we illustrate some of the features that can be obtained when modern statistical tools are applied in the context of nuclear reactions. This work consists of a summary of the progress that has been made in quantifying theoretical uncertainties in this domain, focusing primarily on those uncertainties coming from the effective optical potential as well as their propagation within various reaction theories. We use, as the central example, reactions on the doubly-magic stable nucleus $^{40}$Ca, namely neutron and proton elastic scattering and single-nucleon transfer $^{40}$Ca(d,p)$^{41}$Ca. First, we show different optimization schemes used to constrain the optical potential from differential cross sections and other experimental constraints; we then discuss how these uncertainties propagate to the transfer cross section, comparing two reaction theories. We finish by laying out our future plans.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78870679","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}

引用次数: 21

Application of artificial intelligence in the determination of impact parameter in heavy-ion collisions at intermediate energies 人工智能在确定中能量重离子碰撞参数中的应用

Journal of Physics G Pub Date : 2020-08-26 DOI: 10.1088/1361-6471/abb1f9

Fupeng Li, Yongjia Wang, Hongliang Lü, Pengcheng Li, Qingfeng Li, Fanxin Liu

{"title":"Application of artificial intelligence in the determination of impact parameter in heavy-ion collisions at intermediate energies","authors":"Fupeng Li, Yongjia Wang, Hongliang Lü, Pengcheng Li, Qingfeng Li, Fanxin Liu","doi":"10.1088/1361-6471/abb1f9","DOIUrl":"https://doi.org/10.1088/1361-6471/abb1f9","url":null,"abstract":"The impact parameter is one of the crucial physical quantities of heavy-ion collisions (HICs), and can affect obviously many observables at the final state, such as the multifragmentation and the collective flow. Usually, it cannot be measured directly in experiments but might be inferred from observables at the final state. Artificial intelligence has had great success in learning complex representations of data, which enables novel modeling and data processing approaches in physical sciences. In this article, we employ two of commonly used algorithms in the field of artificial intelligence, the Convolutional Neural Networks (CNN) and Light Gradient Boosting Machine (LightGBM), to improve the accuracy of determining impact parameter by analyzing the proton spectra in transverse momentum and rapidity on the event-by-event basis. Au+Au collisions with the impact parameter of 0$leq$$b$$leq$10 fm at intermediate energies ($E_{rm lab}$=$0.2$-$1.0$ GeV$/$nucleon) are simulated with the ultrarelativistic quantum molecular dynamics (UrQMD) model to generate the proton spectra data. It is found that the average difference between the true impact parameter and the estimated one can be smaller than 0.1 fm. The LightGBM algorithm shows an improved performance with respect to the CNN on the task in this work. By using the LightGBM's visualization algorithm, one can obtain the important feature map of the distribution of transverse momentum and rapidity, which may be helpful in inferring the impact parameter or centrality in heavy-ion experiments.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"21 1","pages":"115104"},"PeriodicalIF":0.0,"publicationDate":"2020-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77145830","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}

引用次数: 24

Magnetized hot and dense quark matter in the Polyakov Nambu–Jona–Lasinio model Polyakov Nambu-Jona-Lasinio模型中的磁化热稠密夸克物质

Journal of Physics G Pub Date : 2020-08-18 DOI: 10.1088/1361-6471/aba03b

Yuan Wang, X. Wen

引用次数: 1

Light sterile neutrinos and their implications on currently running long-baseline and neutrinoless double-beta decay experiments 光不育中微子及其对当前运行的长基线和无中微子双β衰变实验的影响

Journal of Physics G Pub Date : 2020-07-22 DOI: 10.1088/1361-6471/ab9797

Rudra Majhi, C. Soumya, R. Mohanta

{"title":"Light sterile neutrinos and their implications on currently running long-baseline and neutrinoless double-beta decay experiments","authors":"Rudra Majhi, C. Soumya, R. Mohanta","doi":"10.1088/1361-6471/ab9797","DOIUrl":"https://doi.org/10.1088/1361-6471/ab9797","url":null,"abstract":"Recent $nu_e$ appearance data from the Mini Booster Neutrino Experiment (MiniBooNE) are in support of the excess of events reported by the Liquid Scintillator Neutrino Detector (LSND), which provides an indirect hint for the existence of eV-scale sterile neutrino. As these sterile neutrinos can mix with the standard active neutrinos, in this paper we explore the effect of such active-sterile mixing on the determination of various oscillation parameters by the currently running long-baseline neutrino experiments T2K and NO$nu$A. We find that the existence of sterile neutrino can lead to new kind of degeneracies among these parameters which would substantially deteriorate the mass hierarchy sensitivity of NO$nu$A experiment. We further notice that the inclusion of data from T2K experiment helps in resolving the degeneracies. The impact of new CP violating phases $delta_{14}$ and $delta_{34}$ on the maximal CP-violation exclusion sensitivity for NO$nu$A experiment has also been illustrated. Finally, we discuss the implication of such light sterile neutrinos on neutrinoless double beta decay processes in line with recent experimental results, as well as on the sensitivity reach of future experiments.","PeriodicalId":16770,"journal":{"name":"Journal of Physics G","volume":"55 4 1","pages":"095002"},"PeriodicalIF":0.0,"publicationDate":"2020-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83691402","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}

引用次数: 4