Fri·Aug 5, 2022Friday·August 5, 2022

1. 01*

   Proton, deuteron and triton flow measurements in Au+Au collisions at $\sqrt{s_{NN}}=2.4$ GeV

   HADES collaboration: J. Adamczewski-Musch🇩🇪 · O. Arnold🇩🇪 · C. Behnke🇩🇪 · A. Belounnas🇫🇷 · J. C. Berger-Chen🇩🇪 · A. Blanco🇵🇹 · C. Blume🇩🇪 · M. Böhmer🇩🇪 · P. Bordalo🇵🇹 · L. Chlad🇨🇿 · I. Ciepal🇵🇱 · C. Deveaux🇩🇪 and 92 other authors

   High precision measurements of flow coefficients $v_n$ ($n=1-4$) for protons, deuterons and tritons relative to the first-order spectator plane have been performed in Au+Au collisions at $\sqrt{s_{NN}}=2.4$ GeV with the High-Acceptance Di-Electron Spectrometer (HADES) at the SIS18/GSI. Flow coefficients are studied as a function of transverse momentum $p_t$ and rapidity $y_{cm}$ over a large region of phase space and for several classes of collision centrality. A clear mass hierarchy is found for the slope of $v_1$, $d{v}_1/d{y}^{\prime }{|}_{y^{\prime }=0}$ where $y^{\prime }$ is the scaled rapidity, and for $v_2$ at mid-rapidity. Scaling with the number of nucleons is observed for the $p_t$ dependence of $v_2$ and $v_4$ at mid-rapidity, which is indicative for nuclear coalescence as the main process responsible for light nuclei formation. $v_2$ is found to scale with the initial eccentricity $⟨{ϵ}_2⟩$, while $v_4$ scales with $⟨{ϵ}_2{⟩}^2$ and $⟨{ϵ}_4⟩$. The multi-differential high-precision data on $v_1$, $v_2$, $v_3$, and $v_4$ provides important constraints on the equation-of-state of compressed baryonic matter.

   nucl-exEPJA(2023)·51 citations
2. 02*

   Continuum-extrapolated NNLO Valence PDF of Pion at the Physical Point

   Xiang Gao🇺🇸 · Andrew D. Hanlon🇺🇸 · Nikhil Karthik🇺🇸 · Swagato Mukherjee🇺🇸 · Peter Petreczky🇺🇸 · Philipp Scior🇺🇸 · Shuzhe Shi🇺🇸 · Sergey Syritsyn🇺🇸 · Yong Zhao🇺🇸 · Kai Zhou🇩🇪

   We present lattice QCD calculations of valence parton distribution function (PDF) of pion employing next-to-next-leading-order (NNLO) perturbative QCD matching. Our calculations are based on three gauge ensembles of 2+1 flavor highly improved staggered quarks and Wilson--Clover valance quarks, corresponding to pion mass $m_{\pi }=140$~MeV at a lattice spacing $a=0.076$~fm and $m_{\pi }=300$~MeV at $a=0.04,0.06$~fm. This enables us to present, for the first time, continuum-extrapolated lattice QCD results for NNLO valence PDF of the pion at the physical point. Applying leading-twist expansion for renormalization group invariant (RGI) ratios of bi-local pion matrix elements with NNLO Wilson coefficients we extract $2^{\mathrm{nd}}$, $4^{\mathrm{th}}$ and $6^{\mathrm{th}}$ Mellin moments of the PDF. We reconstruct the Bjorken-$x$ dependence of the NNLO PDF from real-space RGI ratios using a deep neural network (DNN) as well as from momentum-space matrix elements renormalized using a hybrid-scheme. All our results are in broad agreement with the results of global fits to the experimental data carried out by the xFitter and JAM collaborations.

   ↳ hep-lathep-exhep-phnucl-ex+1PRD(2022)·77 citations
3. 03*

   The $S$ matrices of elastic $\alpha$-${}^{12}$C scattering at low energies in effective field theory

   Shung-Ichi Ando (Sunmoon U.)🇰🇷

   The elastic $\alpha$-${}^{12}$C scattering at low energies for $l=0,1,2,3,4,5,6$ is studied in effective field theory. We discuss the construction of the $S$ matrices of elastic $\alpha$-${}^{12}$C scattering in terms of the amplitudes of sub-threshold bound and resonant states of ${}^{16}$O, which are calculated from the effective Lagrangian. The parameters appearing in the $S$ matrices are fitted to the phase shift data below the $p$-${}^{15}$N breakup threshold energy, and we find that the phase shifts are well described within the theory.

   ↳ nucl-thhep-phnucl-exPRC(2023)·12 citations
4. 04*

   Exploring medium mass nuclei using effective chiral nucleon-nucleon interactions

   Sota Yoshida🇯🇵

   In the past decades, it has been shown that the three-body force is necessary for a fully microscopic understanding of nuclear many-body systems, and thus efficient schemes for storing and utilizing three-body matrix elements have been developed. However, three-body matrix elements still demand a lot of memory and/or storage and it readily exceeds the limitation of the state-of-the-art supercomputers. We explore the possibility of mimicking the effects of three-body forces in medium-mass region, especially lower $pf$ shell, by density-dependent effective nucleon-nucleon interactions combining with a modern family of chiral nucleon-nucleon interaction and an uncertainty quantification on the coupling constants. We found that some effective nucleon-nucleon potentials give decent description of ground state energies, but also systematic underestimation in charge radii and deficiencies relevant to the $pf$-shell region.

   ↳ nucl-thnucl-ex2 citations
5. 05*

   Semi-inclusive electroproduction of hidden-charm and double-charm hadronic molecules

   Pan-Pan Shi🇨🇳 · Feng-Kun Guo🇨🇳 · Zhi Yang🇨🇳

   The semi-inclusive electroproduction of exotic hadrons, including the $T_{cc}$, $P_{cs}$, and hidden-charm baryon-antibaryon states, is explored under the assumption that they are $S$-wave hadronic molecules of a pair of charmed hadrons. We employ the Monte Carlo event generator Pythia to produce the hadron pairs and then bind them together to form hadronic molecules. With the use of such a production mechanism, the semi-inclusive electroproduction rates are estimated at the order-of-magnitude level. Our results indicate that a larger number of $P_{cs}$ states and ${\Lambda }_c{\bar{\Lambda }}_c$ molecules can be produced at the proposed electron-ion colliders in China (EicC) and in the US (EIC). The results also suggest that the $T_{cc}$ states and other hidden-charm baryon-antibaryon states can be searched for at EIC. Besides, the potential 24-GeV upgrade of the Continuous Beam Accelerator Facility at the Thomas Jefferson National Accelerator Facility can play an important role in the search for the hidden-charm tetraquark and pentaquark states due to its high luminosity.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2022)·14 citations
6. 06*

   First tests of the full SIDDHARTA-2 experimental apparatus with a 4 He gaseous target

   A. Scordo🇮🇹 · C. Amsler🇦🇹 · M. Bazzi🇮🇹 · D. Bosnar🇭🇷 · M. Bragadireanu🇷🇴 · M. Cargnelli🇦🇹 · M. Carminati🇮🇹 · A. Clozza🇮🇹 · G. Deda🇮🇹 · L. De Paolis🇮🇹 · R. Del Grande🇮🇹 · L. Fabbietti🇩🇪 and 29 other authors

   In this paper, we present the first tests performed after the full installation of the SIDDHARTA-2 experimental apparatus on the Interaction Region of the DA{\Phi}NE collider at the INFN National Laboratories of Frascati. Before starting the first measurement of the kaonic deuterium 2p{\rightarrow}1s transition, accurate evaluation of the background rejection. mainly achieved with the Kaon Trigger system, was required. This run, performed in the period 04-26/05/2022 with a 4 He gaseous target, confirmed the 10^5 rejection factor obtained with a reduced version of the setup and different machine conditions in 2021. This important outcome motivated the filling of the target cell with deuterium and the starting of the measurement campaign of the kaonic deuterium 2p{\rightarrow}1s transition.

   ↳ physics.ins-detnucl-exActa Phys.Polon.A(2022)·1 citation
7. 07*

   Lithium fluoride (LiF) target preparation for nuclear physics experiment

   Lalit Kumar Sahoo · Ashok Kumar Mondal · Dipali Basak · Chinmay Basu · Suraj Kumar Karan

   The LiF target preparation on self-supporting Ag backing (LiF/Ag) is discussed in a detailed manner using vacuum evaporation process. The target thickness is measured using the energy loss of three line alpha source. 183.74 {\mu}g/cm 2 thickness of LiF is achieved through the evaporation process. Good uniformity of targets is observed. Non-uniformity in targets is found within 6 %. The XPS analysis confirms the presence of both the F and Li atoms on sample surface.

   ↳ physics.ins-detnucl-exVacuum(2023)·3 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.