Physics Letters B最新文献

{"title":"Evidence of medium response to hard probes using correlations of Z bosons with hadrons in heavy ion collisions","authors":"","doi":"10.1016/j.physletb.2025.140120","DOIUrl":"10.1016/j.physletb.2025.140120","url":null,"abstract":"<div><div>The first measurement of pseudorapidity and azimuthal angle distributions relative to the momentum vector of a Z boson for low transverse momentum (<em>p</em>_T) charged hadrons in lead-lead (PbPb) collisions is presented. By studying the hadrons produced in an event with a high-<em>p</em>_T Z boson (<span><math><mrow><mn>40</mn><mo>&lt;</mo><msub><mi>p</mi><mi>T</mi></msub><mo>&lt;</mo><mn>350</mn><mspace></mspace><mtext>GeV</mtext></mrow></math></span>), the analysis probes how the quark-gluon plasma (QGP) medium created in these collisions affects the parton recoiling opposite to the Z boson. Utilizing PbPb data at a nucleon-nucleon center-of-mass energy <span><math><mrow><msqrt><mrow><mrow><mo>[</mo><mi>b</mi><mo>]</mo></mrow><msub><mi>s</mi><msub><mrow></mrow><mtext>NN</mtext></msub></msub></mrow></msqrt><mo>=</mo><mn>5.02</mn><mspace></mspace><mtext>TeV</mtext></mrow></math></span> from 2018 with an integrated luminosity of 1.67<span><math><mrow><mspace></mspace><msup><mtext>nb</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span> and proton-proton (pp) data at the same energy from 2017 with 301<span><math><mrow><mspace></mspace><msup><mtext>pb</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span>, the distributions are examined in bins of charged-hadron <em>p</em>_T. A significant modification of the distributions for charged hadrons in the range <span><math><mrow><mn>1</mn><mo>&lt;</mo><msub><mi>p</mi><mi>T</mi></msub><mo>&lt;</mo><mn>2</mn><mspace></mspace><mtext>GeV</mtext></mrow></math></span> in PbPb collisions is observed when compared to reference measurements from pp collisions. The data provide new information about the correlation between hard and soft particles in heavy ion collisions, which can be used to test predictions of various jet quenching models. When compared with theoretical predictions, the results are consistent with expectations of a hydrodynamic wake created when the QGP is depleted of energy by the parton propagating through it. Therefore, this Letter presents the first evidence of probe-induced energy depletion and the resulting response by the QGP medium.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140120"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145845480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Observation of renormalization group invariance in symmetry-restored nuclear lattice effective field theory","authors":"Jia-Ai Shi,&nbsp;Chen-Can Wang,&nbsp;Bing-Nan Lu","doi":"10.1016/j.physletb.2026.140303","DOIUrl":"10.1016/j.physletb.2026.140303","url":null,"abstract":"<div><div>Renormalization group (RG) invariance implies that the predictions of effective field theory are independent of the momentum cutoffs introduced during regularization. Here we report the first systematic verification of RG invariance for realistic nuclear few-body systems within nuclear lattice effective field theory. To restore broken continuum rotational and Galilean symmetries, we employ Galilean-invariance-restoration counterterms and use a soft momentum regulator. We calibrate the two- and three-body next-to-next-to leading order (N²LO) chiral forces using <em>A</em> ≤ 3 observables and perform precision quantum Monte Carlo calculations to compute the ⁴He binding energy. The predicted energy remains constant across cutoffs from 250 MeV to 400 MeV and agrees well with the experimental value, with discrepancies of order 100 keV. Our results demonstrate the capability of extracting accurate, cutoff-independent predictions within lattice-regulated ab initio nuclear theory.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140303"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146777459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Pseudodifferential calculus in Schwinger–DeWitt formalism: UV and IR parts","authors":"A.O. Barvinsky ,&nbsp;A.E. Kalugin ,&nbsp;W. Wachowski","doi":"10.1016/j.physletb.2026.140291","DOIUrl":"10.1016/j.physletb.2026.140291","url":null,"abstract":"<div><div>We consider expansions for the kernels of operator functions of second-order minimal operators on a curved background. We show that the terms of these expansions originate in the ultraviolet or infrared regions. We propose a systematic approach to obtaining ultraviolet terms using term-by-term integration of the DeWitt expansion of the heat kernel. We discuss two methods for regularizing infrared divergences arising at intermediate computational steps—using analytic continuation and introducing a mass term—and the relationship between them.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140291"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146777461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Nonlocal advantage of quantum coherence in the black hole quantum atmosphere","authors":"Fei Ming ,&nbsp;Tao-Tao Lu ,&nbsp;Zheng-Qiang Xu ,&nbsp;Li Dong ,&nbsp;Bao-Long Fang ,&nbsp;Xueyou Hu ,&nbsp;Yang Yu ,&nbsp;Hao Yang ,&nbsp;Dong Wang","doi":"10.1016/j.physletb.2026.140242","DOIUrl":"10.1016/j.physletb.2026.140242","url":null,"abstract":"<div><div>The effect of Hawking radiation on nonlocal advantage of quantum coherence (NAQC) is investigated by considering the Hartle-Hawking temperature under the Schwarzschild space-time. We analyze the characteristics of NAQC in the physically accessible and inaccessible regions. It is found that the minimum value for NAQC is indeed corresponding to the peak of Hawking radiation in accessible regions. Owing to the Hawking effect, quantum resource for the accessible and inaccessible regions is redistributed, and the trade-off relation for the information flow is revealed in the black hole. Besides, we examined the influences of Hawking radius, the distance from the black hole center to particle and the Hartle-Hawking constant on NAQC. It indicates that the smaller Hartle-Hawking constant and larger Hawking radius leads to an increase of NAQC in the physically accessible system. In addition, the hierarchical relationship among various quantum resources is verified in the black hole. If NAQC is achieved in the accessible region, the systemic state must be entangled, steerable and Bell nonlocal. Our findings show that the signatures of quantum atmosphere can be detected via NAQC and it offers a valuable insight on understanding the origination of Hawking radiation.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140242"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146109742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Quasi-elastic scattering for the nuclear ground state structure: An intriguing case of 30Si","authors":"Y.K. Gupta ,&nbsp;B. Maheshwari ,&nbsp;G.K. Prajapati ,&nbsp;A.K. Jain ,&nbsp;K. Hagino ,&nbsp;B.N. Joshi ,&nbsp;A. Pal ,&nbsp;N. Sirswal ,&nbsp;Pawan Singh ,&nbsp;S. Dubey ,&nbsp;V.V. Desai ,&nbsp;V. Ranga ,&nbsp;V.B. Katariya ,&nbsp;D. Patel ,&nbsp;H. Vyas ,&nbsp;S. Panwar ,&nbsp;B.V. John ,&nbsp;I. Mazumdar ,&nbsp;B.K. Nayak ,&nbsp;U. Garg","doi":"10.1016/j.physletb.2026.140239","DOIUrl":"10.1016/j.physletb.2026.140239","url":null,"abstract":"<div><div>Quasi-elastic (QEL) scattering measurements have been performed using the ^28,30Si projectiles off the ⁹⁰Zr target at energies around the Coulomb barrier. Coupled-channels (CC) calculations were carried out in a large parameter space of quadrupole and hexadecapole deformations for the N=Z, ²⁸Si and N=Z+2, ³⁰Si nuclei. ²⁸Si at the N=Z line is observed to be uniquely oblate shaped in its ground state. In contrast, for ³⁰Si with just two additional neutrons- oblate, prolate, and spherical CC descriptions are equally compatible with the measurements. To further investigate the nuclear structure evolution with varying neutron number, shell-model calculations were performed. These calculations reveal a sudden change in the nuclear structure aspects at ³⁰Si in going from ²⁸Si to ³²Si. Combined reaction and structure analyses consistently indicate that ³⁰Si does not possess a well-defined intrinsic shape, and it is a potential candidate for “shape fluctuations” in its ground state.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140239"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146109746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Multiloop spectra in general scalar EFTs and CFTs","authors":"Johan Henriksson ,&nbsp;Franz Herzog ,&nbsp;Stefanos R. Kousvos ,&nbsp;Jasper Roosmale Nepveu","doi":"10.1016/j.physletb.2026.140235","DOIUrl":"10.1016/j.physletb.2026.140235","url":null,"abstract":"<div><div>We consider the most general effective field theory (EFT) Lagrangian with scalar fields and derivatives, and renormalise it to substantially higher loop order than existing results in the literature. EFT Lagrangians have phenomenological applications, for example by encoding corrections to the Standard Model from unknown new physics. At the same time, scalar EFTs capture the spectrum of Wilson–Fisher conformal field theories (CFTs) in <span><math><mrow><mn>4</mn><mo>−</mo><mrow><mi>ε</mi></mrow></mrow></math></span> dimensions. Our results are enabled by a more efficient version of the <em>R</em>* method for renormalisation, in which the IR divergences are subtracted via a small-momentum asymptotic expansion. In particular, we renormalise the most general set of composite operators up to engineering dimension six and Lorentz rank two. We exhibit direct applications of our results to Ising (<em>Z</em>₂), <em>O</em>(<em>n</em>), and hypercubic (<em>S_n</em>⋉(<em>Z</em>₂)^<em>n</em>) CFTs, relevant for a plethora of real-world critical phenomena. The computed scaling dimensions agree well with known non-perturbative results, and they lead to new predictions where such results do not yet exist. We thereby expand the understanding of generic EFTs and open new possibilities in diverse fields, such as the numerical conformal bootstrap.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140235"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146134627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Testing non-standard neutrinos in purely leptonic lepton decays","authors":"Han Zhang ,&nbsp;Bai-Cian Ke ,&nbsp;Yao Yu","doi":"10.1016/j.physletb.2026.140233","DOIUrl":"10.1016/j.physletb.2026.140233","url":null,"abstract":"<div><div>We propose a method to probe sterile neutrinos using polarization observables in the purely leptonic decays <span><math><mrow><msup><mi>ℓ</mi><mrow><mo>′</mo><mo>−</mo></mrow></msup><mo>→</mo><msup><mi>ℓ</mi><mo>−</mo></msup><msub><mover><mi>ν</mi><mo>¯</mo></mover><mi>ℓ</mi></msub><msub><mi>ν</mi><msup><mi>ℓ</mi><mo>′</mo></msup></msub></mrow></math></span>. By analyzing angular distributions and asymmetries derived from polarized decay rates, we identify distinctive signatures of sterile neutrino mixing. In particular, we demonstrate that sterile neutrinos can induce singularities in certain asymmetry parameters as functions of the invariant mass squared of the neutrino pair. These singularities occur for sterile neutrino masses <em>m</em>_4<em>ν</em> satisfying <span><math><mrow><msubsup><mi>m</mi><mrow><mn>4</mn><mi>ν</mi></mrow><mn>2</mn></msubsup><mo>&lt;</mo><msubsup><mi>m</mi><mrow><msup><mi>ℓ</mi><mo>′</mo></msup></mrow><mn>2</mn></msubsup><mo>/</mo><mn>2</mn></mrow></math></span>, providing a clear target for experimental investigation. Our results motivate the incorporation of polarized beam sources at future colliders to enhance sensitivity to sterile neutrinos and other new physics.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140233"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146134633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Multiplicity dependence of K*(892) ±  production in pp collisions at s=13 TeV","authors":"","doi":"10.1016/j.physletb.2026.140253","DOIUrl":"10.1016/j.physletb.2026.140253","url":null,"abstract":"<div><div>The first results of K*(892)^± production at midrapidity (|<em>y</em>| &lt; 0.5) in pp collisions at <span><math><mrow><msqrt><mi>s</mi></msqrt><mspace></mspace><mo>=</mo><mspace></mspace><mn>13</mn></mrow></math></span> TeV as a function of the event multiplicity are presented. The K*(892)^± has been reconstructed via its hadronic decay channel K<span><math><mrow><msup><mrow></mrow><mo>*</mo></msup><msup><mrow><mo>(</mo><mn>892</mn><mo>)</mo></mrow><mo>±</mo></msup><mo>→</mo><mspace></mspace><msup><mi>π</mi><mo>±</mo></msup><mspace></mspace><mo>+</mo><mspace></mspace><msubsup><mrow><mrow><mi>K</mi></mrow></mrow><mi>S</mi><mn>0</mn></msubsup></mrow></math></span> using the ALICE detector at the LHC. For each multiplicity class, the differential transverse momentum (<em>p</em>_T) spectrum, the mean transverse momentum ⟨<em>p</em>_T⟩, the <em>p</em>_T-integrated yield (d<em>N</em>/d<em>y</em>), and the ratio of the K*(892)^± to <span><math><msubsup><mrow><mrow><mi>K</mi></mrow></mrow><mi>S</mi><mn>0</mn></msubsup></math></span> yields are reported. These are consistent with previous K*(892)⁰ resonance results with a higher level of precision. Comparisons with phenomenological models such as PYTHIA6, PYTHIA8, EPOS-LHC, and DIPSY are also discussed. For the first time, a significant K*(892)^±/<span><math><msubsup><mrow><mrow><mi>K</mi></mrow></mrow><mi>S</mi><mn>0</mn></msubsup></math></span> suppression in pp collisions is observed at a 7<em>σ</em> level passing from low to high multiplicity events. The ratios of the <em>p</em>_T-differential yields of K*(892)^± and <span><math><msubsup><mrow><mrow><mi>K</mi></mrow></mrow><mi>S</mi><mn>0</mn></msubsup></math></span> in high and low multiplicity events are also presented along with their double ratio. For <em>p</em>_T ≲ 2 GeV/<em>c</em> this double ratio persists below unity by more than 3<em>σ</em> suggesting that the suppression affects mainly low <em>p</em>_T resonances. The measured decreasing trend of the K*(892)^±/<span><math><msubsup><mrow><mrow><mi>K</mi></mrow></mrow><mi>S</mi><mn>0</mn></msubsup></math></span> ratio with increasing multiplicity, which in heavy-ion collisions is typically attributed to the rescattering of decay particles of the short-lived resonances, is reproduced by the EPOS-LHC model without the use of hadronic afterburners.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140253"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146146654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Confinement by monopole loops in inhomogeneous magnetic field","authors":"S. Bolognesi","doi":"10.1016/j.physletb.2026.140274","DOIUrl":"10.1016/j.physletb.2026.140274","url":null,"abstract":"<div><div>We show that a generalized Polyakov mechanism can lead to confinement at weak coupling in <span><math><mrow><mn>3</mn><mo>+</mo><mn>1</mn></mrow></math></span> dimensions when the theory is placed in a non-trivial, spatially varying magnetic field background. Depending on the magnitude of the field and the length scale of its spatial variation, the “dual” Schwinger mechanism for monopole-antimonopole pair creation may or may not be operative. At the threshold, monopole loops in the Euclidean description develop an almost flat direction. In this regime, confinement arises in a way similar to the <span><math><mrow><mn>2</mn><mo>+</mo><mn>1</mn></mrow></math></span> dimensional Polyakov mechanism and the monopoles and antimonopoles are effectively replaced by deconfined “bits” of a monopole loop.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140274"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146160141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Basis representation for nuclear densities from principal component analysis","authors":"Chen-Jun Lv ,&nbsp;Tian-Yu Wu ,&nbsp;Xin-Hui Wu ,&nbsp;Gianluca Colò ,&nbsp;Kouichi Hagino","doi":"10.1016/j.physletb.2026.140283","DOIUrl":"10.1016/j.physletb.2026.140283","url":null,"abstract":"<div><div>We develop an efficient method to represent nuclear densities using basis functions extracted via Principal Component Analysis (PCA). Applying PCA to densities of 75 nuclei calculated with the relativistic continuum Hartree-Bogoliubov (RCHB) theory yields an orthogonal set of components that efficiently capture the dominant features of nuclear density distributions, which can be used as basis functions for nuclear density representation. The first five basis functions account for more than 99.999% of the total variance, demonstrating the efficiency of these PCA basis functions. The PCA basis achieves significantly higher accuracy and faster convergence than the Fourier-Bessel and Sum-of-Gaussians methods for reconstructing both theoretical and experimental densities. This approach provides an efficient and robust representation of nuclear densities, offering a practical tool for experimental density representation and for theories where densities play a central role, such as the orbital-free density functional theory, or the double folding model for nuclear reactions.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"874 ","pages":"Article 140283"},"PeriodicalIF":4.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146777455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}