Mon·Nov 7, 2022Monday·November 7, 2022

1. 01*

   Neutron Yield Calculation from ($\alpha ,n$) Reactions with SOURCES4

   Vitaly A. Kudryavtsev🇬🇧 · Piotr Krawczun · Rayna Bocheva

   Neutrons can induce background events in underground experiments looking for rare processes. Neutrons in a MeV range in deep underground laboratories are produced in spontaneous fission processes and ($\alpha ,n$) reactions. A number of computer codes are available to calculate cross-sections of ($\alpha ,n$) reactions, branching ratios to various states and neutron yields. We have used the SOURCES4 code to calculate neutron yields and energy spectra with input cross-sections and branching ratios taken from experimental data and calculations based on EMPIRE2.19/3.2.3 and TALYS1.9. We report here a comparison of SOURCES4 calculations with experimental data obtained with alpha beams with fixed energies.

   nucl-exhep-exAIP Conf.Proc.(2023)·4 citations
2. 02*

   Systematic investigation of channel coupling effects on elastic, inelastic and neutron transfer channels in ${}^6$Li+${}^{159}$Tb

   Saikat Bhattacharjee🇨🇦 · Piyasi Biswas · Ashish Gupta🇮🇳 · M. K. Pradhan🇮🇳 · N. Deshmukh🇮🇹 · P. Basu🇮🇳 · V.V. Parkar · S. Santra🇮🇳 · K. Ramachandran🇮🇳 · A. Chatterjee🇮🇳 · Subinit Roy🇮🇳 · A. Mukherjee

   Elastic scattering angular distribution for weakly bound nucleus ${}^6$Li on the deformed rare earth ${}^{159}$Tb target nucleus has been measured at energies around the Coulomb barrier. The elastic scattering cross sections for this reaction consist of inelastic contributions from low lying excited states of ${}^{159}$Tb. The pure elastic cross-sections have been extracted from the admixture of elastic and inelastic data. The optical model potential parameters for the system have been obtained from the extracted pure elastic scattering cross sections. Coupled channel calculations have been performed with this set of potential parameters, to compare the theoretical and experimental inelastic scattering cross sections. The work has been extended to obtain the spectroscopic factor for ${}^{158}$Tb+n configuration from the experimental 1n-pickup data.

   nucl-exPRC(2022)·0 citations
3. 03*

   Determination of photo-nuclear cross section of ${}^{61}$Ni($\gamma$,xp) reaction via surrogate ratio technique

   Shaima Akbar · M.M Musthafa · Midhun C.V · Antony Joseph · S.V. Suryanarayana · A. Pal · S. Santra · P. C. Rout · Jyoti Pandey · Bhawna Pandey · H. M. Agrawal · K. C Jagadeesan · S. Ganesan

   The photo nuclear reaction cross section of ${}^{61}$Ni($\gamma$,xp) reaction have been measured by employing surrogate reaction technique. This indirect method is used for the first time to obtain the cross section of photo nuclear reaction. The compound nucleus ${}^{61}$Ni${}^{\ast }$ was populated using the transfer reaction ${}^{59}$Co(${}^6$Li,$\alpha$) at E${}_{lab}=$ 40.5 MeV. To calculate the surrogate ratio, ${}^{60}$Ni($\gamma$,xp) was selected as reference reaction and the corresponding compound nucleus ${}^{60}$Ni${}^{\ast }$ was populated using the transfer reaction ${}^{56}$Fe(${}^6$Li,d) at E${}_{lab}=$ 35.9 MeV. The experimental cross section data of the reference reaction has been taken from EXFOR data libraries. Compound nuclear cross section calculations have been done using EMPIRE 3.2.3 code.

   nucl-ex0 citations
4. 04*

   High-spin spectroscopy in ${}^{207}$At: Evidence of a 29/2${}^{+}$ isomeric state

   Khamosh Yadav🇮🇳 · A. Y. Deo · Madhu · Dhananjaya Sahoo · P. C. Srivastava🇮🇳 · Saket Suman · S. K. Tandel · A. Sharma · I. Ahmed · K. Katre · K. Rojeeta Devi · Sunil Dutt and 4 other authors

   Yrast and near-yrast states above the known 25/2${}^{+}$ isomer in ${}^{207}$At are established for the first time. The level scheme is extended up to 47/2$\hslash$ and 6.5 MeV with the addition of about 60 new $\gamma$-ray transitions. The half-life of the 25/2${}^{+}$ isomer is revisited and a value of $T_{1/2}$ = 107.5(9) ns is deduced. Evidence of a hitherto unobserved 29/2${}^{+}$ isomer in ${}^{207}$At is presented. A systematic study of $B(E3)$ values for the transitions de-exciting the 29/2${}^{+}$ isomer in the neighboring odd-$A$ At isotopes suggests a half-life in the 2$-$4.5 $\mu$s range for this state in ${}^{207}$At. The experimental results are compared with large-scale shell-model calculations performed using the KHM3Y effective interaction in the $Z$ = 50$-$126, $N$ = 82$-$184 model space and an overall good agreement is noted between the theory and the experiment. A qualitative comparison of the excited states and the isomers with analogous states in neighboring nuclei provides further insight into the structure of ${}^{207}$At.

   nucl-exPRC(2023)·10 citations
5. 05*

   Simulations and analysis tools for charge-exchange $(d,{}^2\text{He})$ reactions in inverse kinematics with the AT-TPC

   S. Giraud🇫🇷 · J.C. Zamora🇧🇷 · R.G.T. Zegers🇺🇸 · Y. Ayyad🇪🇸 · D. Bazin🇺🇸 · W. Mittig🇺🇸 · A. Carls · M. DeNudt · Z. Rahman

   Charge-exchange $(d,{}^2\text{He})$ reactions in inverse kinematics at intermediate energies are a very promising method to investigate the Gamow-Teller transition strength in unstable nuclei. A simulation and analysis software based on the $\mathrm{ATTPCROOT}$ package was developed to study these type of reactions with the active-target time projection chamber (AT-TPC). The simulation routines provide a realistic detector response that can be used to understand and benchmark experimental data. Analysis tools and correction routines can be developed and tested from simulations in $\mathrm{ATTPCROOT}$, because they are processed in the same way as the real data. In particular, we study the feasibility of using coincidences with beam-like particles to unambiguously identify the $(d,{}^2\text{He})$ reaction channel, and to develop a kinematic fitting routine for future applications. More technically, the impact of space-charge effects in the track reconstruction, and a possible correction method are investigated in detail. This analysis and simulation package constitutes an essential part of the software development for the fast-beams program with the AT-TPC.

   nucl-exNucl.Instrum.Meth.A(2023)·6 citations
6. 06*

   Relativistic resistive magneto-hydrodynamics code for high-energy heavy-ion collisions

   Kouki Nakamura🇯🇵 · Takahiro Miyoshi🇯🇵 · Chiho Nonaka🇯🇵 · Hiroyuki R. Takahashi🇯🇵

   We construct a relativistic resistive magneto-hydrodynamic (RRMHD) numerical simulation code for high-energy heavy-ion collisions. We split the system of differential equations into two parts, a non-stiff and a stiff part. For the non-stiff part, we evaluate the numerical flux using HLL approximated Riemann solver and execute the time integration by the second-order of Runge-Kutta algorithm. For the stiff part, which appears in Ampere's law, we integrate the equations using semi-analytic solutions of the electric field. We employ the generalized Lagrange multiplier method to ensure the divergence-free constraint for the magnetic field and Gauss's law. We confirm that our code reproduces well the results of standard RRMHD tests in the Cartesian coordinates. In the Milne coordinates, the code with high conductivity is validated against relativistic ideal MHD tests. We also verify the semi-analytic solutions of the accelerating longitudinal expansion of relativistic resistive magneto-hydrodynamics in high-energy heavy-ion collisions in a comparison with our numerical result. Our numerical code reproduces these solutions.

   ↳ nucl-thhep-phnucl-exEPJC(2023)·22 citations
7. 07*

   Letter of intent for ALICE 3: A next-generation heavy-ion experiment at the LHC

   ALICE Collaboration

   This document describes the plans of the ALICE Collaboration for a major upgrade of its detector, referred to as ALICE 3, which is proposed for physics data-taking in the LHC Run 5 and beyond. ALICE 3 will enable an extensive programme to fully exploit the LHC for the study of the properties of strongly interacting matter with high-energy nuclear collisions. The proposed detector layout, based on advanced silicon sensors, features superb pointing resolution, excellent tracking and particle identification over a large acceptance and high readout-rate capabilities. This document discusses the proposed physics programme, the detector concept, and its physics performance for a suite of benchmark measurements.

   ↳ physics.ins-dethep-exnucl-ex221 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.