Journal of Physics G: Nuclear and Particle Physics最新文献

{"title":"Dark photon effect on the rare kaon decay \u0000 KL⃗π0νν¯","authors":"Xuan Wang, A. Thomas","doi":"10.1088/1361-6471/acdfed","DOIUrl":"https://doi.org/10.1088/1361-6471/acdfed","url":null,"abstract":"\u0000 <jats:p>We present an analysis of the effect of a dark photon on the rare kaon decay <jats:inline-formula>\u0000 <jats:tex-math>\u0000<?CDATA ${K}_{L}to {pi }^{0}nu bar{nu }$?>\u0000</jats:tex-math>\u0000 <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\">\u0000 <mml:msub>\u0000 <mml:mrow>\u0000 <mml:mi>K</mml:mi>\u0000 </mml:mrow>\u0000 <mml:mrow>\u0000 <mml:mi>L</mml:mi>\u0000 </mml:mrow>\u0000 </mml:msub>\u0000 <mml:mo>→</mml:mo>\u0000 <mml:msup>\u0000 <mml:mrow>\u0000 <mml:mi>π</mml:mi>\u0000 </mml:mrow>\u0000 <mml:mrow>\u0000 <mml:mn>0</mml:mn>\u0000 </mml:mrow>\u0000 </mml:msup>\u0000 <mml:mi>ν</mml:mi>\u0000 <mml:mover accent=\"true\">\u0000 <mml:mrow>\u0000 <mml:mi>ν</mml:mi>\u0000 </mml:mrow>\u0000 <mml:mrow>\u0000 <mml:mo>¯</mml:mo>\u0000 </mml:mrow>\u0000 </mml:mover>\u0000 </mml:math>\u0000 <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" xlink:href=\"jpgacdfedieqn3.gif\" xlink:type=\"simple\" />\u0000 </jats:inline-formula>. All relevant couplings of the dark photon to the standard model particles are derived explicitly in terms of the dark photon mass and the mixing parameter. We find that the dark photon yields no more than a few percent correction to the standard model branching ratio <jats:inline-formula>\u0000 <jats:tex-math>\u0000<?CDATA $mathrm{Br}({K}_{L}to {pi }^{0}nu bar{nu })$?>\u0000</jats:tex-math>\u0000 <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\">\u0000 <mml:mi>Br</mml:mi>\u0000 <mml:mo stretchy=\"false\">(</mml:mo>\u0000 <mml:msub>\u0000 <mml:mrow>\u0000 <mml:mi>K</mml:mi>\u0000 </mml:mrow>\u0000 <mml:mrow>\u0000 <mml:mi>L</mml:mi>\u0000 </mml:mrow>\u0000 </mml:msub>\u0000 <mml:mo>→</mml:mo>\u0000 <mml:msup>\u0000 <mml:mrow>\u0000 <mml:mi>π</mml:mi>\u0000 </mml:mrow>\u0000 <mml:mrow>\u0000 <mml:mn>0</mml:mn>\u0000 </mml:mrow>\u0000 </mml:msup>\u0000 <mml:mi>ν</mml:mi>\u0000 <mml:mover accent=\"true\">\u0000 ","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44136798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-quasineutron γ-band in 127Xe","authors":"Saikat Chakraborty, H. Sharma, S. Jehangir, S. Tiwary, C. Majumder, A. K. Gupta, G. Bhat, J. Sheikh, N. Rather, Polash Banerjee, S. Ganguly, S. Rai, P. Popli, S. Muralithar, R. Singh, S. Bhattacharjee, Suresh Kumar, Mayank Singh, Ashok Kumar V, R. Palit","doi":"10.1088/1361-6471/acd86a","DOIUrl":"https://doi.org/10.1088/1361-6471/acd86a","url":null,"abstract":"\u0000 Structures of negative parity multi-quasiparticle states in 127Xe have been investigated through in-beam γ-ray spectroscopy. Excited states were populated via 122Sn(9Be, 4nγ)127Xe fusion-evaporation reaction at Ebeam = 48 MeV. Two new negative parity bands have been identified and their structures have been discussed using the triaxial projected shell model (TPSM) approach. One of the bands is established above the Iπ = 27/2- state at 3702 keV and based on the experimental inferences and TPSM results, this band is interpreted as a γ-band built on a three-quasineutron configuration. The second sequence, found above Iπ = 31/2- state at 4848 keV, is proposed to have a two-proton aligned configuration (νh11/2 ⊗ πh11/2\u0000 2), considering the properties of this band with the neighbouring isotopes. The analysis of the TPSM wave function substantiates the proposed interpretation of this band.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49461851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Signatures for shape coexistence and shape/phase transitions in even-even nuclei","authors":"D. Bonatsos, A. Martinou, Spyridon K. Peroulis, T. Mertzimekis, N. Minkov","doi":"10.1088/1361-6471/acd70b","DOIUrl":"https://doi.org/10.1088/1361-6471/acd70b","url":null,"abstract":"\u0000 Systematics of B(E2) transition rates connecting the first excited $0_2^+$ state to the first excited $2_1^+$ state of the ground state band in even-even nuclei indicates that shape coexistence of the ground state band and the first excited $K=0$ band should be expected in nuclei lying within the stripes of nucleon numbers 7-8, 17-20, 34-40, 59-70, 96-112 predicted by the dual shell mechanism of the proxy-SU(3) model, avoiding their junctions, within which high deformation is expected. Systematics of the excitation energies of the $0_2^+$ states in even-even nuclei show that shape coexistence due to proton-induced neutron particle-hole excitations is related to a first order shape/phase transition from spherical to deformed shapes, while shape coexistence due to neutron-induced proton particle-hole excitations is observed along major proton shell closures.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44277995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"α-decay half-life of 212Po at stellar temperatures","authors":"P. Mohr","doi":"10.1088/1361-6471/acd39a","DOIUrl":"https://doi.org/10.1088/1361-6471/acd39a","url":null,"abstract":"\u0000 The decay properties of atomic nuclei may be modified in stellar environments. The present study analyzes the α-decay of 212Po at temperatures of several Giga-Kelvin, typical for explosive stellar environments. Contrary to a recent study which claimed a reduction of the half-life of 212Po by up to five orders of magnitude, the present study shows only a moderate reduction of the half-life of less than one order of magnitude up to 2 GK.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46439324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pairing phase transition in an odd-even hot 69Zn nucleus","authors":"Enakshi Senapati, Satabdi Mondal, S. Bhattacharya, D. Pandit, Nguyen Dinh Dang, N. N. Anh, L. T. Quynh Huong, R. Santra, N. Q. Hưng, B. Dey","doi":"10.1088/1361-6471/acd2f1","DOIUrl":"https://doi.org/10.1088/1361-6471/acd2f1","url":null,"abstract":"\u0000 The pairing phase transition in an odd-even hot-rotating 69Zn nucleus has been investigated by using the reported nuclear level density (NLD) data, which were experimentally extracted from the γ-gated particle spectra. The experimental NLDs have been compared with those obtained within the microscopic exact pairing plus independent-particle model at finite temperature (EP+IPM) along with the results of other microscopic calculations such as the Hartree-Fock BCS (HFBCS) and Hartree-Fock-Bogoliubov plus combinational (HFBC) methods. It is found that the experimental NLDs can be well described by the EP+IPM using the recommended quadrupole deformation parameter β2 = -0.164. Intriguingly, the heat capacity calculated using the EP+IPM NLD exhibits a sharp S-shape, which is not expected in such odd-even hot or hot-rotating system as reported earlier. Changing the deformation parameter β2 does not change much this S-shape. However, increasing or decreasing the pairing gaps could enhance or destroy the S-shaped heat capacity. Therefore, the S-shaped heat capacity in odd-even 69Zn nucleus is explained due to the deformation induced pairing correlation.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47532365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Models and potentials in hadron spectroscopy","authors":"Sreelakshmi M, A. Ranjan","doi":"10.1088/1361-6471/acd1a3","DOIUrl":"https://doi.org/10.1088/1361-6471/acd1a3","url":null,"abstract":"\u0000 In the past twenty years, hadron spectroscopy has made immense progress. Experimental facilities have observed different multiquark states during these years. There are different models and phenomenological potentials to study the nature of interquark interaction. In this work, we have reviewed different quark potentials and models used in hadron spectroscopy.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49618034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neutrinoless double beta decay and sterile neutrino dark matter in extended left right symmetric model","authors":"Bichitra Bijay Boruah, Nayana Gautam, Mrinal Kumar Das","doi":"10.1088/1361-6471/acceba","DOIUrl":"https://doi.org/10.1088/1361-6471/acceba","url":null,"abstract":"\u0000 We have studied a flavor symmetry-based extended left-right symmetric model(LRSM) with a dominant type-II seesaw mechanism and have explored the associated neutrino phenomenology. The particle content of the model includes usual quarks and leptons along with additional sterile fermion per generation in the fermion sector while the scalar content contains Higgs doublets and scalar bidoublet. This extension of LRSM has been realized by using $A_{4}times Z_{4}$ discrete symmetries. In this work, we have included the study of sterile neutrino dark matter(DM) phenomenology and neutrinoless double beta decay within the framework.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44624128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Search for cluster effects in p+12C elastic scattering by a diffractional method","authors":"Luigi Redigolo, D. Dell’Aquila, I. Lombardo, A. Musumarra, M. Pellegriti, G. Verde, M. Vigilante","doi":"10.1088/1361-6471/acceb9","DOIUrl":"https://doi.org/10.1088/1361-6471/acceb9","url":null,"abstract":"\u0000 We investigate medium-energy angular distributions data of proton elastic scattering on $^{12}$C, with the aim to probe the existence of cluster distributions in the ground state of $^{12}$C. In our approach, we exploit Coupled-Channel calculations to describe the scattering from a spheroidal-like structure, and we include a further contribution, based on a diffraction scattering formula, to explicitly take into account a possible triangular $alpha$-cluster structure of the target. From the present analysis, we find a quite small cluster component in $^{12}$C ground state (with an upper limit on the occurrence probability of $1%$, $99.75%$ confidence level) and an inter-cluster distance of $simeq 3.9$ fm. These values are compared with several theoretical predictions reported in the literature.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46220356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unpolarized transverse momentum dependent sea quark asymmetries of light nuclei in nonperturbative QCD","authors":"H. Nematollahi","doi":"10.1088/1361-6471/accd08","DOIUrl":"https://doi.org/10.1088/1361-6471/accd08","url":null,"abstract":"\u0000 We investigate the transverse momentum dependence of sea quark asymmetries in Helium and deuteron nuclei. To this end, we calculate the nuclear sea quark distributions, in first step, based on the modified chiral quark exchange formalism at low $Q^2$ scale ($Q^2=0.35~GeV^2$) in nonperturbative region of quantum chromodynamics (QCD). In this formalism the sea quark distributions are not symmetric because of chiral symmetry breaking. In next step, we compute transverse momentum dependence of sea quark distributions using the covariant parton model (CPM) in which the unpolarized transverse momentum dependent (TMD) quark distribution functions are related to corresponding integrated ones. Finally, we obtain TMD quark-anti quark asymmetry of strange sea for $^3He$ and deuteron and also $(bar{d}-bar{u})$ asymmetry for $^3He$. In order to study the EMC effect in $^3He$ nucleus, we determine the ratio of TMD strange sea asymmetries of $^3He$ and deuteron.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45982328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revisiting proton-proton fusion in chiral effective field theory","authors":"B. Acharya, L. Marcucci, L. Platter","doi":"10.1088/1361-6471/ace3e2","DOIUrl":"https://doi.org/10.1088/1361-6471/ace3e2","url":null,"abstract":"\u0000 We calculate the $S$-factor for proton-proton fusion using chiral effective field theory interactions and currents. By performing order-by-order calculations with a variety of chiral interactions that are regularized and calibrated in different ways, we assess the uncertainty in the $S$-factor from the truncation of the effective field theory expansion and from the sensitivity of the $S$-factor to the short-distance axial current determined from three- and four-nucleon observables. We find that $S(0)=(4.100pm0.019mathrm{(syst)}pm0.013mathrm{(stat)}pm0.008(g_A))times10^{-23}~mathrm{MeV,fm}^2,,$ where the three uncertainties arise, respectively, from the truncation of the effective field theory expansion, use of the two-nucleon axial current fit to few-nucleon observables and variation of the axial coupling constant within the recommended range. The increased value of $S(0)$ compared to previous calculations is mainly driven by an increase in the recommended value for the axial coupling constant and is in agreement with a recent analysis based on pionless effective field theory.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44259389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}