Fri·Oct 4, 2024Friday·October 4, 2024

1. 01*

   Energy dependence of $\varphi$(1020) meson production in nucleus-nucleus collisions at the CERN SPS

   Łukasz Rozpłochowski (for the NA61/SHINE Collaboration)🇵🇱

   This paper presents preliminary results from the NA61/SHINE experiment on $\varphi$ meson production in central Ar+Sc collisions at beam momenta of 150$A$, 75$A$, and 40$A$ GeV/$c$ (corresponding to $\sqrt{s_{NN}}$ = 16.8, 11.9, and 8.8 GeV, respectively). These results include double differential distributions in rapidity ($y$) and transverse momentum ($p_T$), as well as $p_T$-integrated rapidity distributions and total $\varphi$ yields. Additionally, the widths of the rapidity distributions of $\varphi$ and $\varphi /\pi$ yield ratios are compared to those from Pb+Pb and \pp reactions. Notably, this work represents the first-ever measurements of $\varphi$ production in a mid-sized system at SPS energies.

   nucl-exhep-exEPJ Web Conf.(2025)·3 citations
2. 02*

   Revisiting Single Inclusive Jet Production: Small-$R$ Resummation at Next-to-Leading Logarithm

   Kyle Lee🇺🇸 · Ian Moult🇺🇸 · Xiaoyuan Zhang🇺🇸

   The precision description of jet production plays an important role in many aspects of collider physics. In a recent paper we have presented a new factorization theorem for inclusive small radius jet production. The jet function appearing in our factorization theorem exhibits a non-standard renormalization group evolution, which, starting at next-to-leading logarithm (NLL), differs from previous results in the literature. In this paper we perform a first phenomenological study using our newly developed formalism, applying it to compute the spectrum of small radius jets in $e^{+}{e}^{-}\to J+X$ at NLL. We compare our results with previous predictions, highlighting the numerical impact of previously neglected terms throughout phase space. Our approach can be used for a variety of different collider systems, in particular, $ep$ and $pp$ collisions, with broad applications to the jet substructure program. Most importantly, since our factorization theorem is valid to all orders, the approach developed here will enable NNLL resummation of small radius logarithms in inclusive jet production, extending the precision of jet substructure calculations.

   ↳ hep-phhep-exnucl-exnucl-th17 citations
3. 03*

   Post-irradiation examination of a prototype tantalum-clad target for the Beam Dump Facility at CERN

   Tina Griesemer🇨🇭 · Rui Franqueira Ximenes🇨🇭 · Gonzalo Arnau Izquierdo🇨🇭 · Ignacio Aviles Santillana🇨🇭 · Thomas Brehm🇩🇪 · Adria Gallifa Terricabras🇨🇭 · Stefan Höll🇨🇭 · Richard Jacobsson🇨🇭 · Marco Kaiser🇩🇪 · Roman Kuchar🇩🇪 · Ana Teresa Pérez Fontenla🇨🇭 · Alexey Rempel🇩🇪 and 4 other authors

   The Beam Dump Facility (BDF) is a planned fixed-target installation in CERN's North Area, set to start operating in 2031. A proton beam of 400 GeV/c will be delivered in 1 s pulses of 4e13 protons every 7.2 s, amounting to 4e19 protons on target (PoT) per year, with an average thermal power deposition of 305 kW. The experiment requires high-Z and high-density materials and involves challenging thermomechanical conditions; hence, a water-cooled refractory metal core is proposed. To prevent corrosion and erosion, the target materials - tungsten and a molybdenum-based alloy, TZM-, are clad with a tantalum alloy using hot isostatic pressing. To verify the reliability of the target design and manufacturing process, a reduced-scale prototype target was manufactured and irradiated with 2.4e16 PoT in 2018. This paper presents the findings of the post-irradiation examination (PIE) conducted 2.5 years later. The PIE consisted of non-destructive and destructive activities, including film imaging, microscopy, metrology, ultrasonic testing, microstructural analysis, and mechanical and thermal characterization. No irradiation effects resulting from thermal stresses, such as geometrical changes or cracks in the cladding, were observed, and it was determined that the bonding between the core and cladding materials was robust. Moreover, no changes were detected in the microstructures or mechanical properties of the bulk materials. In conclusion, the robustness of the target baseline design and manufacturing process was confirmed, validating its suitability for operating under the desired conditions. Nonetheless, the observed brittleness of sintered tungsten indicates a potential area for improvement to enhance the lifetime of the BDF target. Overall, the examinations provided valuable insights into the performance of the prototype and indicated potential refinements for the future BDF target complex.

   ↳ physics.acc-phhep-exnucl-exphysics.ins-det0 citations
4. 04*

   Wideband Search for Axionlike Dark Matter Using Octupolar Nuclei in a Crystal

   Mingyu Fan🇨🇦 · Bassam Nima🇨🇦 · Aleksandar Radak🇨🇦 · Gonzalo Alonso-Álvarez🇨🇦 · Amar Vutha🇨🇦

   Most of the matter in the Universe is in the form of dark matter, which has evaded detection so far. Ultralight axionlike particles (ALPs) are a class of dark matter candidates that produce measurable signatures in the form of oscillating violations of discrete symmetries in nuclei. We report results from a search for an oscillating parity-odd time-reversal-odd nuclear Schiff moment of ${}^{153}$Eu ions in a crystal, which leads to constraints on ALP-gluon coupling strength across a wide band spanning eight decades in ALP mass.

   ↳ physics.atom-phastro-ph.COhep-phnucl-exPRL(2026)·11 citations
5. 05*

   Simulating collectivity in dense baryon matter with multiple fluids

   Iurii Karpenko🇨🇿 · Jakub Cimerman🇨🇿 · Pasi Huovinen🇵🇱 · Boris Tomasik🇨🇿

   We report on construction of a modern multi-fluid approach to heavy-ion collisions at FAIR/BES energies (MUFFIN) and show the reproduction of basic experimental observables in Au-Au collisions in the RHIC Beam Energy Scan program. We also show the $p_T$-differential and $p_T$-integrated polarization of (anti-)$\Lambda$ hyperons. In MUFFIN simulations, we observe a strong splitting between polarizations of $\Lambda$ and anti-$\Lambda$. The splitting is driven purely by a finite baryon chemical potential.

   ↳ nucl-thnucl-exEPJ Web Conf.(2025)·1 citation
6. 06*

   Transverse Energy-Energy Correlator for Vector Boson-Tagged Hadron Production in $pp$ and $pA$ collisions

   Zhong-Bo Kang🇺🇸 · Sookhyun Lee🇺🇸 · Jani Penttala🇺🇸 · Fanyi Zhao🇺🇸 · Yiyu Zhou🇺🇸

   We investigate the transverse energy-energy correlator (TEEC) event-shape observable for back-to-back $\gamma +h$ and $Z+h$ production in both $pp$ and $pA$ collisions. Our study incorporates nuclear modifications into the transverse-momentum dependent (TMD) factorization framework, with resummation up to next-to-leading logarithmic (NLL) accuracy, for TEEC as a function of the variable $\tau =\left(1+\cos \varphi \right)/2$, where $\varphi$ is the azimuthal angle between the vector boson and the final hadron. We analyze the nuclear modification factor $R_{pA}$ in $p\mathrm{Au}$ collisions at RHIC and $p\mathrm{Pb}$ collisions at the LHC. Our results demonstrate that the TEEC observable is a sensitive probe for nuclear modifications in TMD physics. Specifically, the changes in the $\tau$-distribution shape provide insights into transverse momentum broadening effects in large nuclei, while measurements at different rapidities allow us to explore nuclear modifications in the collinear component of the TMD parton distribution functions in nuclei.

   ↳ hep-phhep-exnucl-exnucl-thPRD(2025)·16 citations
7. 07*

   QCD critical point: recent developments

   Mikhail Stephanov🇺🇸

   Recent developments aimed at mapping QCD phase diagram and the search for the QCD critical point in heavy-ion collisions are briefly reviewed.

   ↳ nucl-thhep-phnucl-exEPJ Web Conf.(2024)·25 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.