{"title":"Ward identities in a two-dimensional gravitational model: anomalous amplitude revisited using a completely regularization-independent mathematical strategy","authors":"G Dallabona, P G de Oliveira, O A Battistel","doi":"10.1088/1361-6471/ad66ed","DOIUrl":"https://doi.org/10.1088/1361-6471/ad66ed","url":null,"abstract":"We present a detailed investigation of the anomalous gravitational amplitude in a simple two-dimensional model with Weyl fermions. We employ a mathematical strategy that completely avoids any regularization prescription for handling divergent perturbative amplitudes. This strategy relies solely on the validity of the linearity of the integration operation and avoids modifying the amplitudes during intermediate calculations, unlike studies using regularization methods. Additionally, we adopt arbitrary routings for internal loop momenta, representing the most general analysis scenario. As expected, we show that surface terms play a crucial role in both preserving the symmetry properties of the amplitude and ensuring the mathematical consistency of the results. Notably, our final perturbative amplitude can be converted into the form obtained using any specific regularization prescription. We consider three common scenarios, one of which recovers the traditional results for gravitational anomalies. However, we demonstrate that this scenario inevitably breaks the linearity of integration, leading to an undesirable mathematical situation. This clean and transparent conclusion, enabled by the general nature of our strategy, would not be apparent in similar studies using regularization techniques.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"396 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193130","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":"Exploring rapidity-even dipolar flow in isobaric collisions at RHIC","authors":"Niseem Magdy and Roy Lacey","doi":"10.1088/1361-6471/ad66ee","DOIUrl":"https://doi.org/10.1088/1361-6471/ad66ee","url":null,"abstract":"Employing the AMPT transport model, we investigate the response of the rapidity-even dipolar flow ( ) and its associated Global Momentum Conservation (GMC) parameter K to structural disparities within 96Ru and 96Zr nuclei. We analyze Ru + Ru and Zr + Zr collisions at a center-of-mass energy of = 200 GeV. Our analysis demonstrates that the eccentricity ε1, and K exhibit subtle yet discernible sensitivity to the input nuclear structure distinctions between 96Ru and 96Zr isobars. This observation suggests that measuring and the GMC parameter in these isobaric collisions could serve as a means to fine-tune the comprehension of their nuclear structure disparities and offer insights to enhance the initial condition assumptions of theoretical models.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"23 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141942463","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":"Weakening of N = 28 shell gap and the nature of 02+ states","authors":"Bhoomika Maheshwari and Kosuke Nomura","doi":"10.1088/1361-6471/ad6170","DOIUrl":"https://doi.org/10.1088/1361-6471/ad6170","url":null,"abstract":"The work reports a novel application of the interacting boson model in light-mass region around 48Ca, that takes into account intruder states and configuration mixing. The model is shown to provide a reasonable description of the observed low-lying yrast and yrare states of the N = 28 even–even isotones from Si to Fe, and even–even Ca isotopes. The nature of states is addressed in terms of the competition between spherical and deformed intruder configurations, and the rigidity of the N = 28 shell gap is tested, particularly for 44S. The isomer in 44S is shown to arise from a weak mixing between the two configurations and called as shape isomer. The unresolved low-lying spectra in 46Ar is also approached using the core-excitations across N = 28 shell. The SU(3) structure in 42Si is supported by the present calculation. The nearly spherical nature of 50Ti, 52Cr, 54Fe and 42,44,46Ca isotopes is found, while the core excitations are found to be essential for the description of yrare states. Shell model calculation is also performed for comparison.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"61 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141771379","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}
P Acharya, M Fritts, D-M Mei, G-J Wang, R Mahapatra and M Platt
{"title":"Exploring charge transport dynamics in a cryogenic P-type germanium detector","authors":"P Acharya, M Fritts, D-M Mei, G-J Wang, R Mahapatra and M Platt","doi":"10.1088/1361-6471/ad60e6","DOIUrl":"https://doi.org/10.1088/1361-6471/ad60e6","url":null,"abstract":"This study explores the dynamics of charge transport within a cryogenic P-type Ge particle detector, fabricated from a crystal cultivated at the University of South Dakota. By subjecting the detector to cryogenic temperatures and an Am-241 source, we observe evolving charge dynamics and the emergence of cluster dipole states, leading to the impact ionization process at 40 mK. Our analysis focuses on crucial parameters: the zero-field cross-section of cluster dipole states and the binding energy of these states. For the Ge detector in our investigation, the zero-field cross-section of cluster dipole states is determined to be 8.45 × 10−11 ± 4.22 × 10−12 cm2. Examination of the binding energy associated with cluster dipole states, formed by charge trapping onto dipole states during the freeze-out process, reveals a value of 0.034 ± 0.0017 meV. These findings shed light on the intricate charge states influenced by the interplay of temperature and electric field, with potential implications for the sensitivity in detecting low-mass dark matter.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"80 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141771382","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}
Ashutosh Kumar Alok, Neetu Raj Singh Chundawat, Arindam Mandal and Bhavya Soni
{"title":"Majorana CP-violating phases and NSI effects in neutrino decay","authors":"Ashutosh Kumar Alok, Neetu Raj Singh Chundawat, Arindam Mandal and Bhavya Soni","doi":"10.1088/1361-6471/ad5b79","DOIUrl":"https://doi.org/10.1088/1361-6471/ad5b79","url":null,"abstract":"In this work, we investigate the impact of neutrino decay in the presence of non-standard interactions (NSI) along with the effects of the Majorana phase on neutrino decay in matter in the context of two-flavor neutrino oscillations. These effects are studied on neutrino oscillation probabilities Pαβ ≡ P(να → νβ), and the difference for several accelerator and reactor neutrino experiments. We find that for Pαβ, the influence of the Majorana phase on decay in matter can be replicated by the simultaneous presence of both decay and NSI. However, precise measurements of the Pαβ and ΔPαβ observables have the potential to unequivocally identify the presence of the Majorana phase by discerning its effects from the concurrent presence of both decay and NSI.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"44 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141614212","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}
László Gyulai, Gábor Bíró, Róbert Vértesi, Gergely Gábor Barnaföldi
{"title":"How far can we see back in time in high-energy collisions using charm hadrons?","authors":"László Gyulai, Gábor Bíró, Róbert Vértesi, Gergely Gábor Barnaföldi","doi":"10.1088/1361-6471/ad59b9","DOIUrl":"https://doi.org/10.1088/1361-6471/ad59b9","url":null,"abstract":"We use open charm production to estimate how far we can see back in time in high-energy hadron-hadron collisions. We analyze the transverse momentum distributions of the identified D mesons from pp, p–Pb and A–A collisions at the ALICE and STAR experiments covering the energy range from <inline-formula>\u0000<tex-math>\u0000<?CDATA $sqrt{{s}_{mathrm{NN}}}=200,mathrm{GeV}$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msqrt><mml:mrow><mml:msub><mml:mrow><mml:mi>s</mml:mi></mml:mrow><mml:mrow><mml:mi>NN</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:msqrt><mml:mo>=</mml:mo><mml:mn>200</mml:mn><mml:mspace width=\"0.25em\"></mml:mspace><mml:mi>GeV</mml:mi></mml:math>\u0000<inline-graphic xlink:href=\"jpgad59b9ieqn1.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula> up to 7 TeV. Within a non-extensive statistical framework, the common Tsallis parameters for D mesons represent higher temperature and more degrees of freedom than that of light-flavour hadrons. Assuming Bjorken-expansion, the production of D mesons corresponds to a significantly earlier proper time, <italic toggle=\"yes\">τ</italic>\u0000<sub>D</sub> = (0.18 ± 0.06)<italic toggle=\"yes\">τ</italic>\u0000<sub>LF</sub>.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"78 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141567775","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}
Chong-Xing Yue, Xiao-Chen Sun, Na-Qian Zhang, Yang-Yang Bu
{"title":"Lepton flavour violation signal of the singly charged scalar singlet at the ILC","authors":"Chong-Xing Yue, Xiao-Chen Sun, Na-Qian Zhang, Yang-Yang Bu","doi":"10.1088/1361-6471/ad59ba","DOIUrl":"https://doi.org/10.1088/1361-6471/ad59ba","url":null,"abstract":"The singly charged <italic toggle=\"yes\">SU</italic>(2)<sub>\u0000<italic toggle=\"yes\">L</italic>\u0000</sub> singlet scalar is one of the very interesting new particles, as it can generate neutrino masses at loop level, produce contributions to various flavour observables. We study the possibility of detecting this kind of scalar predicted by the singly-charged scalar model at ILC via the lepton flavour violation process <inline-formula>\u0000<tex-math>\u0000<?CDATA ${e}^{+}{e}^{-}to {S}^{+}{S}^{-}to mu e+{/}!!!!{E}$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup><mml:mo>→</mml:mo><mml:msup><mml:mrow><mml:mi>S</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>S</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup><mml:mo>→</mml:mo><mml:mi>μ</mml:mi><mml:mi>e</mml:mi><mml:mo>+</mml:mo><mml:menclose notation=\"updiagonalstrike\"><mml:mi>E</mml:mi></mml:menclose></mml:math>\u0000<inline-graphic xlink:href=\"jpgad59baieqn1.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula>. Considering the constraints on the free parameters, we obtain the expected sensitivities of the ILC with the center of mass energy <inline-formula>\u0000<tex-math>\u0000<?CDATA $sqrt{s}=1,mathrm{TeV}$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msqrt><mml:mrow><mml:mi>s</mml:mi></mml:mrow></mml:msqrt><mml:mo>=</mml:mo><mml:mn>1</mml:mn><mml:mspace width=\"0.25em\"></mml:mspace><mml:mi>TeV</mml:mi></mml:math>\u0000<inline-graphic xlink:href=\"jpgad59baieqn2.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula> and the integrated luminosity <inline-formula>\u0000<tex-math>\u0000<?CDATA ${ mathcal L }=$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:mi mathvariant=\"script\">L</mml:mi><mml:mo>=</mml:mo></mml:math>\u0000<inline-graphic xlink:href=\"jpgad59baieqn3.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula> 1.5 ab<sup>−1</sup> to the parameter space of the singly-charged scalar model. The prospective excluded mass range at 95% C.L. is <italic toggle=\"yes\">M</italic>\u0000<sub>\u0000<italic toggle=\"yes\">S</italic>\u0000</sub> ≳ 470 GeV, 410 GeV for the branching ratio <inline-formula>\u0000<tex-math>\u0000<?CDATA ${{ mathcal B }}_{mu e}$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msub><mml:mrow><mml:mi mathvariant=\"script\">B</mml:mi></mml:mrow><mml:mrow><mml:mi>μ</mml:mi><mml:mi>e</mml:mi></mml:mrow></mml:msub></mml:math>\u0000<inline-graphic xlink:href=\"jpgad59baieqn4.gif\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula> = 100% , 50%, respectively, while the scalar with <italic toggle=\"yes\">M</italic>\u0000<sub>\u0000<italic toggle=\"yes\">S</italic>\u0000</sub> ≳ 300 GeV is excluded at 95% C.L. for <inline-formula>\u0000<tex-math>\u0000<?CDATA ${{ mathcal B }}_{mu e}$?>\u0000</tex-math>\u0000<mml:math overflow=\"scroll\"><mml:msub><mml:mrow><mml:mi mathvariant=\"script\">B</mml:mi></mml:mrow><mml:mrow><mml:mi>μ</mml:mi","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"366 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141567774","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}
T R Routray, S Sahoo, X Viñas, D N Basu and M Centelles
{"title":"Equation of state of hot neutron star matter using finite range simple effective interaction","authors":"T R Routray, S Sahoo, X Viñas, D N Basu and M Centelles","doi":"10.1088/1361-6471/ad57d7","DOIUrl":"https://doi.org/10.1088/1361-6471/ad57d7","url":null,"abstract":"The equation of state (EoS) of hot neutron star matter (NSM) of n+p+e+μ composition in β-equilibrium is studied for both neutrino-free isothermal and neutrino-trapped isoentropic conditions, using the formalism where the thermal evolution is built upon its zero-temperature predictions in a self-consistent manner. The accuracy of the parabolic approximation, often used in the finite temperature calculation of hot NSM, is verified by comparing with the results obtained from the exact evaluation in the neutrino-free NSM. The EoS of neutrino-trapped isoentropic matter at low entropic condition, relevant to the core-collapsing supernovae, is formulated. In the isoentropic matter, the particle fractions and EoS have marginal variance as entropy per particle vary between 1 and 3 (in the unit of kB), but the temperature profile shows marked variation. The isentropes are found to be much less sensitive to the nuclear matter incompressibility, but have large dependence on the slope parameter L. The bulk properties of the neutron stars predicted by the isoentropic EoSs for different entropy are calculated. A model calculation for the early stage evolution of protoneutron star to neutron star configuration is also given.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"35 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141509387","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}
T J Gao, H D Wang, Jing-Bin Lu, Yi Lu, Pei-Yao Yang and M J Qin
{"title":"Prediction of the 1st excitation energy of odd–odd nuclei with the Bayesian neural network approach","authors":"T J Gao, H D Wang, Jing-Bin Lu, Yi Lu, Pei-Yao Yang and M J Qin","doi":"10.1088/1361-6471/ad5196","DOIUrl":"https://doi.org/10.1088/1361-6471/ad5196","url":null,"abstract":"A Bayesian neural network (BNN) is developed to predict the 1st excitation energy of odd–odd nuclei. Aside from the proton number and neutron number, we introduce two empirical physical quantities into the input layer. is introduced to distinguish even–even, odd–odd and odd-A nuclei; and the so-called Casten factor is introduced to stand for collectivity. The BNN is trained with an experimental dataset of the 1st excitation energy for 434 odd–odd, 649 even–even and 1050 odd-A nuclei. After training, the BNN predicts the 1st excitation energy of odd–odd nuclei with a rms of 0.21 MeV. Examples of Dy, Gd, Eu and Cs isotopes are also shown. The BNN results show moderate predictive ability, in comparison with results from the projected Hartree–Fock method.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"13 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141516933","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}
D Siegmann, F Edzards, C Bruch, M Biassoni, M Carminati, M Descher, C Fiorini, C Forstner, A Gavin, M Gugiatti, R Hiller, D Hinz, T Houdy, A Huber, P King, P Lechner, S Lichter, D Mießner, A Nava, A Onillon, D C Radford, D Spreng, M Steidl, P Trigilio, K Urban, D Vénos, J Wolfb and S Mertens
{"title":"Development of a silicon drift detector array to search for keV-scale sterile neutrinos with the KATRIN experiment","authors":"D Siegmann, F Edzards, C Bruch, M Biassoni, M Carminati, M Descher, C Fiorini, C Forstner, A Gavin, M Gugiatti, R Hiller, D Hinz, T Houdy, A Huber, P King, P Lechner, S Lichter, D Mießner, A Nava, A Onillon, D C Radford, D Spreng, M Steidl, P Trigilio, K Urban, D Vénos, J Wolfb and S Mertens","doi":"10.1088/1361-6471/ad4bf8","DOIUrl":"https://doi.org/10.1088/1361-6471/ad4bf8","url":null,"abstract":"Sterile neutrinos in the keV mass range present a viable candidate for dark matter. They can be detected through single β -decay, where they cause small spectral distortions. The Karlsruhe Tritium Neutrino (KATRIN) experiment aims to search for keV-scale sterile neutrinos with high sensitivity. To achieve this, the KATRIN beamline will be equipped with a novel multi-pixel silicon drift detector focal plane array named TRISTAN. In this study, we present the performance of a TRISTAN detector module, a component of the eventual 9-module system. Our investigation encompasses spectroscopic aspects such as noise performance, energy resolution, linearity, and stability.","PeriodicalId":16766,"journal":{"name":"Journal of Physics G: Nuclear and Particle Physics","volume":"21 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141516934","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}