PaperPanorama
FAQ

Nuclear Theory·nucl-th

Tuesday·September 20, 2022

13 papers—7 primary·6 cross-listed

All13Primary7Cross-lists6
  1. 08

    Exclusive production in ultraperipheral Pb+Pb collisions to NLO pQCD

    K. J. Eskola🇫🇮 · C. A. Flett🇫🇮 · V. Guzey🇫🇮 · T. Löytäinen🇫🇮 · H. Paukkunen🇫🇮

    We present the first NLO pQCD study of coherent exclusive photoproduction in ultraperipheral heavy-ion collisions (UPCs) at the LHC. Taking the generalized parton distributions (GPDs) in their forward limit, as parton distribution functions (PDFs), we quantify the NLO contributions in the rapidity-differential cross section, show that the real part of the amplitude must not be neglected, study the gluon and quark contributions, chart the scale-choice and PDF uncertainties, and compare the NLO results with LHC and HERA data. We show that the scale dependence is significant but a scale choice can be found with which we reproduce the 2.76 and 5.02 TeV UPC data. In particular, we show that the process is clearly more sensitive to the nuclear quark PDFs than thought before.

    ↳ hep-phnucl-thActa Phys.Polon.Supp.(2023)·1 citation
  2. 09

    Weinberg's Compositeness

    U. van Kolck🇫🇷

    Nearly 60 years ago Weinberg suggested a criterion for particle "compositeness", which has acquired new life with the discovery of new, exotic hadrons. His idea resonates with model-based intuition. I discuss the role it plays in the context of another of Weinberg's creations, the model-independent framework of effective field theories.

    ↳ hep-phnucl-thSymmetry(2022)·31 citations
  3. 10

    Nucleon spin decomposition with one dynamical gluon

    Siqi Xu🇨🇳 · Chandan Mondal🇨🇳 · Xingbo Zhao🇨🇳 · Yang Li🇨🇳 · James P. Vary🇺🇸

    We solve for the light-front wave functions of the nucleon from a light-front quantum chromodynamics (QCD) effective Hamiltonian with three-dimensional confinement. We obtain solutions using constituent three quarks combined with three quarks and one gluon Fock components. The resulting light-front wave functions provide a good quality description of the nucleon's quark distribution functions following QCD scale evolution. We present the effects from incorporating a dynamical gluon on the nucleon's gluon densities, helicity distribution and orbital angular momentum that constitutes the nucleon spin sum rule.

    ↳ hep-phnucl-thPRD(2023)·57 citations
  4. 11

    Transverse momentum broadening from NLL BFKL to all orders in pQCD

    Paul Caucal🇺🇸 · Yacine Mehtar-Tani🇺🇸

    We study, to all orders in perturbative QCD, the universal behavior of the saturation momentum controlling the transverse momentum distribution of a fast parton propagating through a dense QCD medium with large size . Due to the double logarithmic nature of the quantum evolution of the saturation momentum, its large asymptotics is obtained by slightly departing from the double logarithmic limit of either next-to-leading log (NLL) BFKL or leading order DGLAP evolution equations. At fixed coupling, or in conformal SYM theory, we derive the large expansion of up to order . In QCD with massless quarks, where conformal symmetry is broken by the running of the strong coupling constant, the one-loop QCD -function fully accounts for the universal terms in the expansion. Therefore, the universal coefficients of this series are known exactly to all orders in .

    ↳ hep-phhep-thnucl-thPRD(2023)·9 citations
  5. 12

    Shape evolution in the rapidly rotating Gd nucleus

    H. Pai · S. Rajbanshi · Somnath Nag · Sajad Ali · R. Palit · G. Mukherjee · F. S. Babra · R. Banik · Soumik Bhattacharya · S. Biswas · S. Chakraborty · R. Donthi and 5 other authors

    Ground state band of Gd has been investigated following their population in the Sn(Cl,~p2n)Gd reaction at 195 MeV of beam energy using a large array of Compton suppressed HPGe clovers as the detection setup. Apart from other spectroscopic measurements, level lifetimes of the states have been extracted using the Doppler Shift Attenuation Method. Extracted quadrupole moment along with the pairing independent cranked Nilsson-Strutinsky model calculations for the quadrupole band reveal that the nucleus preferably attains triaxiality with = -30. The calculation though shows a slight possibility of rotation around the longest possible principal axis at high spin 30 which is beyond the scope of the present experiment.

    ↳ nucl-exnucl-th0 citations
  6. 13

    Vector dark boson mediated feeble interaction between fermionic dark matter and strange quark matter in quark stars

    Debashree Sen🇮🇳 · Atanu Guha🇰🇷

    We study the structural properties like the gravitational mass, radius and tidal deformability of dark matter (DM) admixed strange quark stars (SQSs). For the purpose we consider the vector MIT Bag model to describe the strange quark matter (SQM) and investigate the possible presence of accreted DM in the SQSs consequently forming DM admixed SQSs. We introduce feeble interaction between SQM and the accreted fermionic DM via a vector dark boson mediator. Considering the present literature, in the context of possible presence of DM in SQSs, this work is the first to consider interaction between DM and SQM in the DM admixed SQSs. The mass of the DM fermion () and the vector mediator () and the coupling () between them are determined in accordance with the constraint from Bullet cluster and the present day relic abundance, respectively. We find that the presence of DM reduces both the mass and radius of the star compared to the no-DM case. The massive the DM fermion, the lower the values of maximum mass and radius of the DM admixed SQSs. For the chosen values of and corresponding values of and , the computed structural properties of the DM admixed SQSs satisfy all the various present day astrophysical constraints.We obtain massive DM admixed SQSs configurations consistent with the GW190814 observational data. Hence the secondary compact object associated with this event may be a DM admixed SQS.

    ↳ hep-phastro-ph.COastro-ph.HEnucl-thMNRAS(2022)·27 citations

Affiliations

first authorsco-authorsvia INSPIRE