Tue·Oct 17, 2023Tuesday·October 17, 2023

1. 01*

   Fragmentation of projectile nucleus

   Janchiv Shinebayar · Ravdandorj Togoo · Tseepeldorj Baatar · Baatar Otgongerel · Maamuu Sovd · Narankhuu Khishigbuyan · Murdorj Urangua

   The temperature characteristics of carbon spectator fragments formed in carbon collisions with carbon nuclei at a primary momentum of 4.2 GeV/c per nucleon were presented and discussed on corrected experimental data. As well as studied the multiplicities formed by the spectator protons, deuterons, and tritons in the inelastic nucleus-nucleus interactions. We found that the temperature absorbed by the spectator fragments is dependent on their mass.

   nucl-ex0 citations
2. 02*

   Measurement of the transverse single-spin asymmetry for forward neutron production in a wide $p_T$ range in polarized $p+p$ collisions at $\sqrt{s}=510$ GeV

   M. H. Kim🇯🇵 · O. Adriani🇮🇹 · E. Berti🇮🇹 · L. Bonechi🇮🇹 · R. D'Alessandro🇮🇹 · Y. Goto🇯🇵 · B. Hong🇰🇷 · Y. Itow🇯🇵 · K. Kasahara🇯🇵 · Y. Kim🇰🇷 · J. H. Lee🇺🇸 · S. H. Lee🇰🇷 and 13 other authors

   Transverse single-spin asymmetries $A_{\text{N}}$ of forward neutrons at pseudorapidities larger than 6 had only been studied in the transverse momentum range of $p_{\text{T}}<0.4$ GeV/$c$. The RHICf Collaboration has extended the previous measurements up to 1.0 GeV/$c$ in polarized $p+p$ collisions at $\sqrt{s}=510$GeV, using an electromagnetic calorimeter installed in the zero-degree area of the STAR detector at the Relativistic Heavy Ion Collider. The resulting $A_{\text{N}}$s increase in magnitude with $p_{\text{T}}$ in the high longitudinal momentum fraction $x_{\text{F}}$ range, but reach a plateau at lower $p_{\text{T}}$ for lower $x_{\text{F}}$. For low transverse momenta the $A_{\text{N}}$s show little $x_{\text{F}}$ dependence and level off from intermediate values. For higher transverse momenta the $A_{\text{N}}$s show also an indication to reach a plateau at increased magnitudes. The results are consistent with previous measurements at lower collision energies, suggesting no $\sqrt{s}$ dependence of the neutron asymmetries. A theoretical model based on the interference of $\pi$ and $a_1$ exchange between two protons could partially reproduce the current results, however an additional mechanism is necessary to describe the neutron $A_{\text{N}}$s over the whole kinematic region measured.

   nucl-exhep-exPRD(2024)·4 citations
3. 03*

   Image-current mediated sympathetic laser cooling of a single proton in a Penning trap down to 170 mK axial temperature

   C. Will🇩🇪 · M. Wiesinger🇩🇪 · P. Micke🇩🇪 · H. Yildiz🇩🇪 · T. Driscoll🇩🇪 · S. Kommu🇩🇪 · F. Abbass🇩🇪 · B. P. Arndt🇩🇪 · B. B. Bauer🇩🇪 · S. Erlewein🇨🇭 · M. Fleck🇯🇵 · J. I. Jäger🇩🇪 and 13 other authors

   We demonstrate a new temperature record for image-current mediated sympathetic cooling of a single proton in a cryogenic Penning trap by laser-cooled ${}^9$Be${}^{+}$. An axial mode temperature of 170 mK is reached, which is a 15-fold improvement compared to the previous best value. Our cooling technique is applicable to any charged particle, so that the measurements presented here constitute a milestone towards the next generation of high-precision Penning-trap measurements with exotic particles.

   ↳ physics.atom-phnucl-exphysics.ins-detquant-phPRL(2024)·5 citations
4. 04*

   Multi-source thermal model describing multi-region structure of transverse momentum spectra of identified particles and parameter dynamics of system evolution in relativistic collisions

   Jia-Yu Chen🇨🇳 · Mai-Ying Duan🇨🇳 · Fu-Hu Liu · Khusniddin K. Olimov🇺🇿

   In this article, the multi-region structure of transverse momentum ($p_T$) spectra of identified particles produced in relativistic collisions is studied by the multi-component standard distribution (the Boltzmann, Fermi-Dirac, or Bose-Einstein distribution) in the framework of a multi-source thermal model. Results are interpreted in the framework of string model phenomenology in which the multi-region of $p_T$ spectra corresponds to the string hadronization in the cascade process of string breaking. The contributions of the string hadronizations from the first-, second-, and third-, i.e., last-generations of string breakings mainly form high-, intermediate-, and low-$p_T$ regions, respectively. From the high- to low-$p_T$ regions, the extracted volume parameter increases rapidly, and temperature and flow velocity parameters decrease gradually. The multi-region of $p_T$ spectra reflects the volume, temperature, and flow velocity dynamics of the system evolution. Due to the successful application of the multi-component standard distribution, this work reflects that the simple classical theory can still play a great role in the field of complex relativistic collisions.

   ↳ hep-phhep-exnucl-exnucl-thIndian J.Phys.(2024)·6 citations
5. 05*

   Light-flavor particle production in high-multiplicity pp collisions at $\sqrt{\text{s}}=13$ TeV as a function of transverse spherocity

   ALICE Collaboration

   Results on the transverse spherocity dependence of light-flavor particle production ($\pi$, K, p, $\varphi$, ${\mathrm{K}}^{\ast 0}$, ${\mathrm{K}}_{\mathrm{S}}^0$, $\Lambda$, $\Xi$) at midrapidity in high-multiplicity pp collisions at $\sqrt{s}=13$ TeV were obtained with the ALICE apparatus. The transverse spherocity estimator ($S_{\mathrm{O}}^{p_{\mathrm{T}}=1}$) categorizes events by their azimuthal topology. Utilizing narrow selections on $S_{\text{O}}^{p_{\mathrm{T}}=1}$, it is possible to contrast particle production in collisions dominated by many soft initial interactions with that observed in collisions dominated by one or more hard scatterings. Results are reported for two multiplicity estimators covering different pseudorapidity regions. The $S_{\mathrm{O}}^{p_{\mathrm{T}}=1}$ estimator is found to effectively constrain the hardness of the events when the midrapidity ($\left|\eta \right|<0.8$) estimator is used. The production rates of strange particles are found to be slightly higher for soft isotropic topologies, and severely suppressed in hard jet-like topologies. These effects are more pronounced for hadrons with larger mass and strangeness content, and observed when the topological selection is done within a narrow multiplicity interval. This demonstrates that an important aspect of the universal scaling of strangeness enhancement with final-state multiplicity is that high-multiplicity collisions are dominated by soft, isotropic processes. On the contrary, strangeness production in events with jet-like processes is significantly reduced. The results presented in this article are compared with several QCD-inspired Monte Carlo event generators. Models that incorporate a two-component phenomenology, either through mechanisms accounting for string density, or thermal production, are able to describe the observed strangeness enhancement as a function of $S_{\mathrm{O}}^{p_{\mathrm{T}}=1}$.

   ↳ hep-exnucl-exJHEP(2024)·33 citations
6. 06*

   The $nnn$ and $ppp$ correlation functions

   A. Kievsky🇮🇹 · E. Garrido🇪🇸 · M. Viviani🇮🇹 · L.E. Marcucci🇮🇹 · L. Serksnyte🇨🇭 · R. Del Grande🇮🇹

   Scattering experiments with three free nucleons in the ingoing channel are extremely challenging in terrestrial laboratories. Recently, the ALICE Collaboration has successfully measured the scattering of three protons indirectly, by using the femtoscopy method in high-energy proton-proton collisions at the Large Hadron Collider. In order to establish a connection with current and future measurements of femtoscopic three-particle correlation functions, we analyse the scenarios involving $nnn$ and $ppp$ systems using the hyperspherical adiabatic basis. The correlation function is a convolution of the source function and the corresponding scattering wave function. The finite size of the source allows for the use of the free scattering wave function in most of the adiabatic channels except the lowest ones. The scattering wave function has been computed using two different potential models: $(i)$ a spin-dependent Gaussian potential with parameters fixed to reproduce the scattering length and effective range and $(ii)$ the Argonne $v_{18}$ nucleon-nucleon interaction. Moreover, in the case of three protons, the Coulomb interaction has been considered in its hypercentral form. The results presented here have to be considered as a first step in the description of three-particle correlation functions using the hyperspherical adiabatic basis, opening the door to the investigation of other systems, such as the $pp\Lambda$ system. For completeness, the comparison with the measurement by the ALICE Collaboration is shown assuming different values of the source radius.

   ↳ nucl-thnucl-exPRC(2024)·16 citations
7. 07*

   Blinding for precision scattering experiments: The MUSE approach as a case study

   J. C. Bernauer🇺🇸 · E. W. Cline🇺🇸 · H. Atac🇺🇸 · W. J. Briscoe🇺🇸 · A. Christopher Ndukwe🇺🇸 · E. J. Downie🇺🇸 · I. P. Fernando🇺🇸 · T. Gautam🇺🇸 · R. Gilman🇺🇸 · R. Goldin🇮🇱 · M. Kohl🇺🇸 · I. Lavrukhin🇺🇸 and 18 other authors

   Human bias is capable of changing the analysis of measured data sufficiently to alter the results of an experiment. It is incumbent upon modern experiments, especially those investigating quantities considered contentious in the broader community, to blind their analysis in an effort to minimize bias. The choice of a blinding model is experiment specific, but should also aim to prevent accidental release of results before an analysis is finalized. In this paper, we discuss common threats to an unbiased analysis, as well as common quantities that can be blinded in different types of nuclear physics experiments. We use the Muon Scattering Experiment as an example, and detail the blinding scheme used therein.

   ↳ physics.data-annucl-ex5 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.