Thu·Jun 13, 2024Thursday·June 13, 2024

1. 01*

   Jet modification via ${\pi }^0$-hadron correlations in Au$+$Au collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV

   PHENIX Collaboration: N.J. Abdulameer · U. Acharya · A. Adare · S. Afanasiev · C. Aidala · N.N. Ajitanand · Y. Akiba · H. Al-Bataineh · J. Alexander · M. Alfred · K. Aoki · N. Apadula and 524 other authors

   High-momentum two-particle correlations are a useful tool for studying jet-quenching effects in the quark-gluon plasma. Angular correlations between neutral-pion triggers and charged hadrons with transverse momenta in the range 4--12~GeV/$c$ and 0.5--7~GeV/$c$, respectively, have been measured by the PHENIX experiment in 2014 for Au$+$Au collisions at $\sqrt{s_{{}_{NN}}}=200$~GeV. Suppression is observed in the yield of high-momentum jet fragments opposite the trigger particle, which indicates jet suppression stemming from in-medium partonic energy loss, while enhancement is observed for low-momentum particles. The ratio and differences between the yield in Au$+$Au collisions and $p$$+$$p$ collisions, $I_{AA}$ and ${\Delta }_{AA}$, as a function of the trigger-hadron azimuthal separation, $\Delta \varphi$, are measured for the first time at the Relativistic Heavy Ion Collider. These results better quantify how the yield of low-$p_T$ associated hadrons is enhanced at wide angle, which is crucial for studying energy loss as well as medium-response effects.

   nucl-exPRC(2024)·7 citations
2. 02*

   Reactor Antineutrino Directionality Measurement with the PROSPECT-I Detector

   M. Andriamirado🇺🇸 · B. Balantekin🇺🇸 · C. D. Bass🇺🇸 · O. Benevides Rodrigues🇺🇸 · E. P. Bernard🇺🇸 · N. S. Bowden🇺🇸 · C. D. Bryan🇺🇸 · R. Carr🇺🇸 · T. Classen🇺🇸 · A. J. Conant🇺🇸 · G. Deichert🇺🇸 · M. J. Dolinski🇺🇸 and 37 other authors

   The PROSPECT-I detector has several features that enable measurement of the direction of a compact neutrino source. In this paper, a detailed report on the directional measurements made on electron antineutrinos emitted from the High Flux Isotope Reactor is presented. With an estimated true neutrino (reactor to detector) direction of $\varphi =40.8°\pm 0.7°$ and $\theta =98.6°\pm 0.4°$, the PROSPECT-I detector is able to reconstruct an average neutrino direction of $\varphi =39.4°\pm 2.9°$ and $\theta =97.6°\pm 1.6°$. This measurement is made with approximately 48000 Inverse Beta Decay signal events and is the most precise directional reconstruction of reactor antineutrinos to date.

   nucl-exhep-exphysics.ins-detPRD(2025)·5 citations
3. 03*

   Lighting up the Photon Wigner Distribution via Dilepton Productions

   Yu Shi🇨🇳 · Lin Chen🇪🇸 · Shu-Yi Wei🇨🇳 · Bo-Wen Xiao🇨🇳

   We present a systematic investigation of lepton pair production through photon-photon fusion processes in heavy-ion collisions. It is demonstrated that the dilepton production at a given impact parameter ($b_{\perp }$) with a fixed transverse momentum imbalance ($q_{\perp }$) can be factorized into a unified formula in terms of the Wigner photon distribution of heavy nuclei. We show that this framework provides a comprehensive description of all the relevant data from RHIC to the LHC, with a strong evidence that the quasi-real photon can be radiated not only from the nucleus as a whole, standing for the coherent contribution, but also from the sub-structures inside the nucleus, representing the incoherent contribution. Further predictions are made for the anisotropies in the correlations between $q_{\perp }$, $b_{\perp }$, and the dilepton transverse momentum ($P_{\perp }$). This will help us to constrain the photon Wigner distribution which plays a crucial role to study the gluonic matter of nucleus at small-$x$ through the diffractive photoproduction processes in heavy ion collision.

   ↳ hep-phhep-exnucl-exnucl-thPLB(2025)·13 citations
4. 04*

   Weak interaction axial form factors of the octet baryons in nuclear medium

   G. Ramalho🇰🇷 · K. Tsushima🇧🇷 · Myung-Ki Cheoun🇰🇷

   We study the axial-vector and the induced pseudoscalar form factors associated with the weak transitions between the octet baryon members in nuclear medium, using a covariant constituent quark model. We extend previous calculations of the axial transition form factors from the vacuum (free space) to the nuclear medium (symmetric nuclear matter). The extension of the model to the nuclear medium takes into account the modifications of the properties of hadrons in the medium (masses and coupling constants), as determined by the quark-meson coupling model. The axial-vector ($G_A$) and the induced pseudoscalar ($G_P$) form factors are evaluated for different values of the nuclear density $\rho$ in terms of the square transfer momentum $q^2=-Q^2$. We conclude that, in general, the $G_A$ and $G_P$ form factors are reduced in the nuclear medium. The reduction is stronger for light baryons and high densities. The medium modifications are milder for the heavier octet baryons, particularly at large $Q^2$. The calculations presented here can be used to estimate the cross sections of neutrino and antineutrino scattering with nucleus, and neutrino and antineutrino scattering with hyperons bound to a nucleus, as well as those in the cores of compact stars.

   ↳ hep-phhep-exhep-latnucl-ex+1PRD(2025)·9 citations
5. 05*

   Design,fabrication and characterization of 8x9 n-type silicon pad array for sampling calorimetry

   Sawan · G. Tambave · J. L. Bouly · O. Bourrion · T. Chujo · A. Das · M. Inaba · V. K. S. Kashyap · C. Krug · R. Laha · C. Loizides · B. Mohanty and 4 other authors

   This paper reports the development and testing of n-type silicon pad array detectors targeted for the Forward Calorimeter (FoCal) detector, which is an upgrade of the ALICE detector at CERN, scheduled for data taking in Run~4~(2029-2034). The FoCal detector includes hadronic and electromagnetic calorimeters, with the latter made of tungsten absorber layers and granular silicon pad arrays read out using the High Granularity Calorimeter Readout Chip~(HGCROC). This paper covers the Technology Computer-Aided Design (TCAD) simulations, the fabrication process, current versus voltage (IV) and capacitance versus voltage (CV) measurements, test results with a blue LED and ${}^{90}$Sr beta source, and neutron radiation hardness tests. IV measurements for the detector showed that 90\% of the pads had leakage current below 10~nA at full depletion voltage. Simulations predicted a breakdown voltage of 1000~V and practical tests confirmed stable operation up to 500~V without breakdown. CV measurements in the data and the simulations gave a full depletion voltage of around 50~V at a capacitance of 35~pF. LED tests verified that all detector pads responded correctly. Additionally, the 1$\times$1 cm${}^2$ pads were also tested with the neutron radiations at a fluence of $5\times 10^{13}$ 1~MeV~n${}_{eq}$/cm${}^2$.

   ↳ physics.ins-dethep-exnucl-exJINST(2025)·2 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.