Nuclear Theory·nucl-th

Friday·December 8, 2023

12 papers—5 primary·7 cross-listed

06
Spin-flip gluon GTMD $F_{1, 2}$ at small- $x$
Sanskriti Agrawal🇮🇳 · Nahid Vasim🇮🇳 · Raktim Abir🇮🇳
Until recently the spin-flip processes in the deep inelastic scatterings are thought to be suppressed in the high energy. We found a positive intercept for the spin-flip generalized transverse momentum-dependent parton distribution (GTMDs) $Re (F_{1, 2})$ as, \begin{eqnarray} {\rm Re}(F_{1,2}) \sim \left(\frac{1}{x}\right)^{{\bar \alpha}_s\left(4\ln2-8/3\right)} \left(\cos 3\phi_{k\Delta} +\cos \phi_{k\Delta}\right). \nonumber \end{eqnarray} This is done by analytically solving the integro-differential evolution equation for $Re (F_{1, 2})$ , recently proposed by Hatta and Zhou, in the dilute regime. Interestingly, the surviving solution corresponds to conformal spin $n = 2$ and carries an explicit $cos 3 ϕ_{k Δ} + cos ϕ_{k Δ}$ azimuthal dependence. As the imaginary part of $F_{1, 2}$ , is related to the spin-dependent odderon or gluon Siver function and scales as $Im (F_{1, 2}) \sim x^{0}$ , the positive intercept for $Re (F_{1, 2})$ , implies that it is expected to dominate over the gluon Siver function in the small- $x$ limit - and may directly impact the modeling of unpolarised GTMDs and associated spin-flip processes.
↳ hep-phhep-latnucl-thPRD(2024)·9 citations
07
Energy dependent nuclear suppression from gluon saturation in exclusive vector meson production
Heikki Mäntysaari🇫🇮 · Farid Salazar🇺🇸 · Björn Schenke🇺🇸
We calculate the exclusive $J / ψ$ photoproduction cross section at high energies from the Color Glass Condensate approach. The results are compared to the center-of-mass energy dependent $γ + A \to J / ψ + A$ cross sections extracted from measurements in ultra peripheral heavy ion collisions at RHIC and LHC. We predict strong saturation-driven nuclear suppression at high energies, while LHC data prefers even stronger suppression. We explore the effect of nucleon shape fluctuations on the nuclear suppression in the coherent and incoherent cross sections, and show that the most recent measurement of the $∣ t ∣$ -differential incoherent $J / ψ$ cross section prefers large event-by-event fluctuations of the nucleon substructure in heavy nuclei, comparable to that found for a free proton.
↳ hep-phnucl-thPRD(2024)·39 citations
08
Photonuclear reactions on the stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 MeV
F.A. Rasulova · N.V. Aksenov · S.I. Alekseev · R.A. Aliev · S.S. Belyshev · I. Chuprakov · N.Yu. Fursova · A.S. Madumarov · J.H. Khushvaktov · A.A. Kuznetsov · B.S. Yuldashev
The experiments were performed at bremsstrahlung end-point energies of 10-23 MeV with the beam from the MT-25 microtron with the use of the {\gamma}-activation technique. The experimental values of relative yields were compared with theoretical results obtained on the basis of TALYS with the standard parameters and the combined model of photonucleon reactions. Including isospin splitting in the combined model of photonucleon reactions allows to describe experimental data on reactions with proton escape in energies range from 10 to 23 MeV. Therefore, taking into account isospin splitting is necessary for a correct description of the decay of the GDR.
↳ nucl-exastro-ph.IMnucl-thPRC(2025)·2 citations
09
Pulse profile variability associated with the glitch of PSR J1048 $-$ 5832
P. Liu · J.-P. Yuan · M.-Y. Ge · W.-T. Ye · S.-Q. Zhou · S.-J. Dang · Z.-R. Zhou · E. Gügercinoğlu · W.-H. Wang · P. Wang · A. Li · D. Li · N. Wang
PSR J1048 $-$ 5832 (B1046 $-$ 58) is a Vela-like pulsar that has exhibited multiple glitch events. In this study, we analyze the timing data spanning nearly 16 years, acquired from both the Fermi Gamma-ray Space Telescope and the Parkes 64 m radio telescope. As a result, a total of five glitches are detected within this dataset. Among them, a previously unknown small glitch is newly found at MJD 56985(9) (November 24, 2014), making it the smallest glitch recorded from this source so far. The increments of the spin frequency and its first derivative are $Δ ν \approx 2.2 (3) \times 1 0^{- 8}$ Hz, and $Δ ν ˙ \approx 3 (2) \times 1 0^{- 15}$ s $^{- 2}$ , respectively. Significant changes in the integrated normalized mean pulse profile are detected following three of the five glitch events, notably in the radio band. Although no evidence of a correlation is found between the spin-down rate and profile evolution, the jump phenomenon of $W_{55}$ (pulse width at the 55% peak amplitude) after the glitch in the narrow mode suggests that the glitch may influence the profile change. We discuss the influence of glitches on the pulsar's emission properties in terms of platelet motion by a crustquake and also put constraints on the equation of state from the moment of inertia and response timescales of involved superfluid layers inside the neutron star.
↳ astro-ph.HEnucl-thMNRAS(2024)·14 citations
10
Revisiting inclusive production of J/psi and Upsilon in high-energy gamma-gamma collisions
Yelyzaveta Yedelkina🇫🇷 · Jean-Philippe Lansberg🇫🇷 · Maxim Nefedov🇫🇷
The impact of Next-to-Leading Order (NLO) QCD corrections to the differential distributions of J/psi and Upsilon mesons produced inclusively in gamma-gamma collisions is discussed for the kinematical conditions of LEP II for DELPHI and at the future Circular Electron-Positron Collider (CEPC). We take into account all sizeable contributions at LO in v^2 in NRQCD factorisation: 1) pure QED process gamma + gamma -> J/psi(3S^1_1) + \gamma up to alpha^3 alpha_s, 2) single-resolved-photon contributions up to alpha_s^4, 3) gamma+gamma -> J/psi + c c-bar up to alpha^2 alpha_s and 4) gamma+gamma -> J/psi + ggg up to alpha^2 alpha_s^3. We will also discuss the pure QED process as a contribution to the exclusive production in ultra-peripheral heavy-ion collisions (UPC) at the LHC.
↳ hep-phhep-exnucl-exnucl-thPoS(2024)·2 citations
11
Investigation of the analog of the $P_{c}$ states-the doubly charmed molecular pentaquarks
Xuejie Liu🇨🇳 · Yue Tan🇨🇳 · Xiaoyun Chen🇨🇳 · Dianyong Chen🇨🇳 · Hongxia Huang🇨🇳 · Jialun Ping🇨🇳
Motivated by the LHCb Collaboration's observation of a doubly charmed tetraquark state $T_{cc} (3875)$ , we systematically investigate the existence of doubly charmed pentaquark states using the resonating group method based on the QDCSM framework. The effective potential of the two involved hadrons and the bound state dynamics are included in the present work. Moreover, we have also calculated the scattering phase shifts of open channels by channel coupling to look for possible resonance states. Our estimations indicate that there is a bound state in $I (J^{P}) = \frac{3}{2} (\frac{5}{2}^{-})$ , with a mass of $4461.7$ MeV. Additionally, five resonance states can be obtained by coupling the open channel, which are $Ξ_{cc} ρ$ and $Σ_{c} D^{*}$ with $I (J^{P}) = \frac{1}{2} (\frac{1}{2}^{-})$ , $Λ_{c} D^{*}$ and $Σ_{c} D^{*}$ with $I (J^{P}) = \frac{1}{2} (\frac{3}{2}^{-})$ and $Σ_{c} D^{*}$ with $I (J^{P}) = \frac{3}{2} (\frac{1}{2}^{-})$ respectively. The existence of these predicted doubly charmed pentaquark states needs to be supported by experimental measurements and discoveries. We hope that some experiments can find evidence of these states.
↳ hep-phnucl-thPRC(2026)·14 citations
12
Incoherent diffractive dijet production and gluon Bose enhancement in the nuclear wave function
Tiyasa Kar🇺🇸 · Alexander Kovner🇺🇸 · Ming Li🇺🇸 · Vladimir V. Skokov🇺🇸
We investigate the effect of gluon Bose enhancement in the nuclear wave function on the dijet production in incoherent diffractive processes in DIS and ultraperipheral collisions. We demonstrate that Bose enhancement leads to an enhancement of diffractive dijet production cross section when the transverse momenta of the two jets are aligned at zero relative angle. This enhancement is maximal when the magnitude of the transverse momenta of the two jets are equal, and disappears rather quickly as a function of the ratio of the two momenta. We study both the dilute limit and fully nonlinear dense regime where the nuclear wave function is evolved with the leading order JIMWLK equation. In both cases we observe a visible effect, with it being enhanced by the evolution due to the dynamical generation of the color neutralization scale.
↳ hep-phnucl-thJHEP(2024)·6 citations

Affiliations

first authorsco-authorsvia INSPIRE

Spin-flip gluon GTMD F1,2​ at small-x

Energy dependent nuclear suppression from gluon saturation in exclusive vector meson production

Photonuclear reactions on the stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 MeV

Pulse profile variability associated with the glitch of PSR J1048−5832

Revisiting inclusive production of J/psi and Upsilon in high-energy gamma-gamma collisions

Investigation of the analog of the Pc​ states-the doubly charmed molecular pentaquarks

Incoherent diffractive dijet production and gluon Bose enhancement in the nuclear wave function

Affiliations

Spin-flip gluon GTMD $F_{1, 2}$ at small- $x$

Pulse profile variability associated with the glitch of PSR J1048 $-$ 5832

Investigation of the analog of the $P_{c}$ states-the doubly charmed molecular pentaquarks