arXiv - PHYS - Nuclear Theory最新文献_第7页

Does nuclear medium affect the transverse momentum-dependent parton distributions of valence quark of pions? 核介质是否会影响对子的价夸克的横动量相关部分子分布？

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05394

Navpreet Kaur, Satyajit Puhan, Reetanshu Pandey, Arvind Kumar, Suneel Dutt, Harleen Dahiya

引用次数: 0

Polarizabilities from kaon Compton scattering 高子康普顿散射的极化能力

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05955

Dominik Stamen, Jan Luca Dammann, Yannis Korte, Bastian Kubis

引用次数: 0

Emergent chirality and superfluidity of parity-doubled baryons in neutron stars 中子星中出现的奇异性和奇偶翻倍重子的超流动性

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05670

Shigehiro Yasui, Muneto Nitta, Chihiro Sasaki

{"title":"Emergent chirality and superfluidity of parity-doubled baryons in neutron stars","authors":"Shigehiro Yasui, Muneto Nitta, Chihiro Sasaki","doi":"arxiv-2409.05670","DOIUrl":"https://doi.org/arxiv-2409.05670","url":null,"abstract":"We propose novel superfluids induced by the parity-doubled baryons. The\u0000parity-doubled baryons, i.e., a nucleon $N(940)$ with spin-parity\u0000$J^{P}=1/2^{+}$ and an excited nucleon $N^{ast}(1535)$ with $J^{P}=1/2^{-}$ in\u0000vacuum, become degenerate at sufficiently high density where the chiral\u0000symmetry is restored. In this study, we extend the conventional $mathrm{U}(1)$\u0000chiral symmetry to the higher dimensional symmetries, dubbed emergent chiral\u0000symmetries, including the naive and mirror assignments as their subgroups.\u0000Starting with the Lagrangian up to four-point interactions among the neutron\u0000$n$ and its chiral partner $n^{ast}$, neutral components in $N$ and\u0000$N^{ast}$, in pure neutron matter, we investigate the properties of the ground\u0000state with a pairing gap generated by the $n$ and $n^{ast}$ in the mean-field\u0000approximation. We find vector-type condensates that induce the dynamical\u0000breaking of a new class of internal symmetries, emergent chiral symmetries, as\u0000well as the baryon number and the rotational symmetries of the real space,\u0000indicating the appearance of massless Nambu-Goldstone bosons consisting of six\u0000quarks: emergent pions, superfluid phonons, and magnons, respectively. We also\u0000study the fermionic excitation modes at low-energy scales, and show that they\u0000exhibit a spatial anisotropy of the propagation at the Dirac cone in momentum\u0000space. Some phenomenological implications are advocated, shedding new light on\u0000the properties of neutron stars.","PeriodicalId":501573,"journal":{"name":"arXiv - PHYS - Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206581","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: 0

Asymptotically conformal CFL quark matter within a nonlocal chiral quark model 非局部手性夸克模型中渐近保形的 CFL 夸克物质

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05859

Oleksii Ivanytskyi

{"title":"Asymptotically conformal CFL quark matter within a nonlocal chiral quark model","authors":"Oleksii Ivanytskyi","doi":"arxiv-2409.05859","DOIUrl":"https://doi.org/arxiv-2409.05859","url":null,"abstract":"We propose a three-flavor nonlocal NJL model of quark matter with the scalar\u0000attractive, vector repulsive and diquark pairing interaction channels. The\u0000model is treated within the separable approximation to obtain the EoS of cold\u0000quark matter. The analysis of the high density asymptotics of the model allows\u0000us to conclude about its qualitative agreement with the perturbative QCD.\u0000Particularly, a color superconducting CFL state is found to be the ground one\u0000at high densities. The conformal limit of speed of sound and dimensionless\u0000interaction measure are also shown to be reached from below and above,\u0000respectively. The model is applied to modelling NSs within the scenario of\u0000early quark deconfinement triggered by the gravitational instability of the NS\u0000matter due to the BEC of a spin-color-flavor singlet three-diquark bound state,\u0000the light sexaquark, stable against the weak and strong decays. A conservative\u0000estimate of the sexaquark mass based on the most up-to-date results from QCD\u0000sum rules and a constituent quark model assumes an early quark deconfinement\u0000with the onset mass below $1~rm M_odot$. The scenario is shown to be\u0000consistent with the present observational constraints on the mass-radius\u0000relation and tidal deformability of NSs. Given the fact that the proposed model\u0000by construction exhibits an asymptotically conformal behavior, we consider the\u0000question about approximately conformal quark matter in NSs. We report a\u0000non-perturbative energy density range, which is inaccessible in NSs and where\u0000the speed of sound and dimensionless interaction measure of the CFL quark\u0000matter simultaneously attain the conformal values.","PeriodicalId":501573,"journal":{"name":"arXiv - PHYS - Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206528","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: 0

Confronting new NICER mass-radius measurements with phase transition in dense matter and compact twin stars 将新的 NICER 质量半径测量结果与致密物质和紧凑孪生星中的相变联系起来

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05322

Jia Jie LiSWU, Chongqing, Armen SedrakianFrankfurt U., FIAS and U. Wroclaw, Mark AlfordWashington U., St. Louis

{"title":"Confronting new NICER mass-radius measurements with phase transition in dense matter and compact twin stars","authors":"Jia Jie LiSWU, Chongqing, Armen SedrakianFrankfurt U., FIAS and U. Wroclaw, Mark AlfordWashington U., St. Louis","doi":"arxiv-2409.05322","DOIUrl":"https://doi.org/arxiv-2409.05322","url":null,"abstract":"The (re)analysis of data on the X-ray emitting pulsars PSR J0030+0451 and PSR\u0000J0740+6620, as well as new results on PSR J0437-4715, are confronted with the\u0000predictions of the equation of state (EoS) models allowing for strong\u0000first-order phase transition for the mass-radius ($M$-$R$) diagram. We use\u0000models that are based on a covariant density functional (CDF) EoS for nucleonic\u0000matter at low densities and a quark matter EoS, parameterized by the speed of\u0000sound, at higher densities. To account for the variations in the ellipses for\u0000PSR J0030+0451 obtained from different analyses, we examined three scenarios to\u0000assess their consistency with our models, focusing particularly on the\u0000potential formation of twin stars. We found that in two scenarios, where the\u0000ellipses for PSR J0030+0451 and PSR J0437-4715 with masses close to the\u0000canonical mass $sim 1.4,M_{odot}$ are significantly separated, our models\u0000allow for the presence of twin stars as a natural explanation for potential\u0000differences in the radii of these stars.","PeriodicalId":501573,"journal":{"name":"arXiv - PHYS - Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206533","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: 0

Strong decays of $a_0$, $f_0$, $f_2$, and $K^*_2$ resonances as dynamically generated states of two vector mesons 作为两个矢量介子动态生成态的 $a_0$、$f_0$、$f_2$ 和 $K^*_2$ 共振的强衰变

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05302

Qing-Hua Shen, Li-Sheng Geng, Ju-Jun Xie

引用次数: 0

Bound state basics 绑定状态基础知识

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05660

Paul Hoyer

{"title":"Bound state basics","authors":"Paul Hoyer","doi":"arxiv-2409.05660","DOIUrl":"https://doi.org/arxiv-2409.05660","url":null,"abstract":"Perturbative expansions for atoms in QED are developed around interacting\u0000states, typically defined by the Schr\"odinger equation. Calculations are\u0000nevertheless done using the standard Feynman diagram expansion around free\u0000states. The classical $-alpha/r$ potential is then obtained through an\u0000infinite sum of ladder diagrams. The complexity of this approach may have\u0000contributed to bound states being omitted from QFT textbooks, restricting the\u0000field to select experts. The confinement scale 1 fm of QCD must be introduced without changing the\u0000Lagrangian. This can be done via a boundary condition on the gauge field, which\u0000affects the bound state potential. The absence of confinement in Feynman\u0000diagrams may be due to the free field boundary condition. Poincar'e invariance is realized dynamically for bound states, i.e., the\u0000interactions are frame dependent. Gauge theories have instantaneous\u0000interactions, due to gauge fixing at all points of space at the same time. In\u0000bound state perturbation theory each order must have exact Poincar'e\u0000invariance. This is non-trivial even for atoms at lowest order. I summarize a perturbative approach to equal time bound states in QED and\u0000QCD, using a Fock expansion in temporal ($A^0=0$) gauge. The longitudinal\u0000electric field $E_L$ is instantaneous and need not vanish at spatial infinity\u0000for the constituents of color singlet states in QCD. Poincar'e covariance\u0000determines the boundary condition for $E_L$ up to a universal scale,\u0000characterised by the gluon field energy density of the vacuum. A non-vanishing\u0000density contributes a linear term to the $qbar{q}$ potential, while $qqq,\u0000qbar{q}g$ and $gg$ color singlet states get analogous confining potentials.","PeriodicalId":501573,"journal":{"name":"arXiv - PHYS - Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206531","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: 0

A simple explanation for the absence of the spherical nuclei 球形核缺失的简单解释

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05723

Tao Wang

引用次数: 0

Probing strangeness with event topology classifiers in pp collisions at the LHC with rope hadronization mechanism in PYTHIA 利用PYTHIA中的绳索强子化机制，在大型强子对撞机的pp对撞中使用事件拓扑分类器探测奇异性

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05454

Suraj Prasad, Bhagyarathi Sahoo, Sushanta Tripathy, Neelkamal Mallick, Raghunath Sahoo

{"title":"Probing strangeness with event topology classifiers in pp collisions at the LHC with rope hadronization mechanism in PYTHIA","authors":"Suraj Prasad, Bhagyarathi Sahoo, Sushanta Tripathy, Neelkamal Mallick, Raghunath Sahoo","doi":"arxiv-2409.05454","DOIUrl":"https://doi.org/arxiv-2409.05454","url":null,"abstract":"In relativistic heavy-ion collisions, the formation of a deconfined and\u0000thermalized state of partons, known as quark-gluon plasma, leads to enhanced\u0000production of strange hadrons in contrast to proton-proton (pp) collisions,\u0000which are taken as baseline. This observation is known as strangeness\u0000enhancement in heavy-ion collisions and is considered one of the important\u0000signatures that can signify the formation of QGP. However, in addition to\u0000strangeness enhancement, recent measurements hint at observing several\u0000heavy-ion-like features in high-multiplicity pp collisions at the LHC energies.\u0000Alternatively, event shape observables, such as charged particle multiplicity,\u0000transverse spherocity, transverse sphericity, charged particle flattenicity,\u0000and relative transverse activity classifiers, can fundamentally separate hard\u0000interaction-dominated jetty events from soft isotropic events. These features\u0000of event shape observables can probe the observed heavy-ion-like features in pp\u0000collisions with significantly reduced selection bias and can bring all\u0000collision systems on equal footing. In this article, we present an extensive\u0000summary of the strange particle ratios to pions as a function of different\u0000event classifiers using the PYTHIA~8 model with color reconnection and rope\u0000hadronization mechanisms to understand the microscopic origin of strangeness\u0000enhancement in pp collisions and also prescribe the applicability of these\u0000event classifiers in the context of strangeness enhancement. Charged-particle\u0000flattenicity is found to be most suited for the study of strangeness\u0000enhancement, and it shows a similar quantitative enhancement as seen for the\u0000analysis based on the number of multi-parton interactions.","PeriodicalId":501573,"journal":{"name":"arXiv - PHYS - Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206530","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: 0

Exclusive vector-quarkonium photoproduction at NLO in alpha_s in collinear factorisation with evolution of the generalised parton distributions and high-energy resummation α_s中NLO的排他性矢量-夸克鎓光生成与广义粒子分布和高能重和的演化的对偶因式分解

arXiv - PHYS - Nuclear Theory Pub Date : 2024-09-09 DOI: arxiv-2409.05738

C. A. Flett, J. P. Lansberg, S. Nabeebaccus, M. Nefedov, P. Sznajder, J. Wagner

{"title":"Exclusive vector-quarkonium photoproduction at NLO in alpha_s in collinear factorisation with evolution of the generalised parton distributions and high-energy resummation","authors":"C. A. Flett, J. P. Lansberg, S. Nabeebaccus, M. Nefedov, P. Sznajder, J. Wagner","doi":"arxiv-2409.05738","DOIUrl":"https://doi.org/arxiv-2409.05738","url":null,"abstract":"We perform the first complete one-loop study of exclusive photoproduction of\u0000vector quarkonia off protons in Collinear Factorisation (CF) including the\u0000scale evolution of the Generalised Parton Distributions (GPDs). We confirm the\u0000perturbative instability of the cross section at high photon-proton-collision\u0000energies (W_gamma+p) at Next-to-Leading Order (NLO) in alpha_s and solve this\u0000issue by resumming higher-order QCD corrections, which are enhanced by a\u0000logarithm of the parton energies, using High-Energy Factorisation (HEF) in the\u0000Doubly-Logarithmic Approximation (DLA) matched to CF. Our NLO CF + DLA HEF\u0000results are in agreement with the latest HERA data, show a smaller sensitivity\u0000to the factorisation and renormalisation scales compared to Born-order results.\u0000Quark-induced channels via interference with gluon ones are found to contribute\u0000at most 20% of the cross section for W_gamma+p > 100 GeV. Our results also show\u0000that such exclusive cross sections cannot be accurately obtained from the\u0000square of usual Parton Distribution Functions (PDFs) and clearly illustrate the\u0000importance of quarkonium exclusive photoproduction to advance our understanding\u0000of the 3D content of the nucleon in terms of gluons. Our work provides an\u0000important step towards a correct interpretation of present and future\u0000experimental data collected at HERA, the EIC, the LHC and future experiments.","PeriodicalId":501573,"journal":{"name":"arXiv - PHYS - Nuclear Theory","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206529","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: 0