Nuclear Theory·nucl-th

Monday·July 8, 2019

5 papers—2 primary·3 cross-listed

03
[Submitted on 4 Jul 2019] (cross-list from hep-ph)
Skewness of the elliptic flow distribution in $s_{_{NN}}$ = 5.02~TeV PbPb collisions from HYDJET++ model
P. Cirkovic🇷🇸 · J. Milosevic🇷🇸 · L. Nadderd🇷🇸 · F. Wang🇨🇳 · X. Zhu🇨🇳
The elliptic flow ( $v_{2}$ ) event-by-event fluctuations in PbPb collisions at 5.02~TeV are analyzed within the HYDJET++ model. Using the multi-particle, so called Q-cumulant method, $v_{2} {2}$ , $v_{2} {4}$ , $v_{2} {6}$ and $v_{2} {8}$ are calculated and used to study their ratios and to construct skewness ( $γ_{1}^{e x p}$ ) as a measure of the asymmetry of the elliptic flow distribution. Additionally, in order to check if there is a hydrodynamics nature in the elliptic collectivity generated by the HYDJET++ model, the ratio of $v_{2} {6} - v_{2} {8}$ and $v_{2} {4} - v_{2} {6}$ distribution is calculated. The analysis is performed as a function of the collision centrality. In order to check the HYDJET++ model responses, the results of this analysis are compared to the corresponding experimental measurements by CMS. A good qualitative and rather good quantitative agreement is found.
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1907.02588 [pdf]
PRC(2020)·2 citations
04
[Submitted on 5 Jul 2019] (cross-list from quant-ph)
Spectral control over $γ$ -ray echo using a nuclear frequency comb system
Chia-Jung Yeh · Po-Han Lin · Xiwen Zhang · Olga Kocharovskaya · Wen-Te Liao
Two kinds of spectral control over $γ$ -ray echo using a nuclear frequency comb system are theoretically investigated. A nuclear frequency comb system is composed of multiple nuclear targets under magnetization (hyperfine splitting), mechanical motion (Doppler shift) or both, namely, moving and magnetized targets. In frequency domain the unperturbed single absorption line of $γ$ -ray therefore splits into multiple lines with equal spacing and becomes a nuclear frequency comb structure. We introduce spectral shaping and dynamical splitting to the frequency comb structure respectively to optimize the use of a medium and to break the theoretical maximum of echo efficiency, i.e., 54\%. Spectral shaping scheme leads to the reduction of required sample resonant thickness for achieving high echo efficiency of especially a broadband input. Dynamical splitting method significantly advances the echo efficiency up to 67\% revealed by two equivalent nuclear frequency comb systems. We also show that using only few targets is enough to obtain good echo performance, which significantly eases the complexity of implementation. Our results extend quantum optics to 10keV regime and lay the foundation of the development of $γ$ -ray memory.
Comments:
5 pages, 4 figures
Subjects:
Quantum Physics (quant-ph); Nuclear Theory (nucl-th); Atomic Physics (physics.atom-ph); physics.optics (physics.optics)
arXiv:
1907.02672 [pdf]
3 citations
05
[Submitted on 5 Jul 2019] (cross-list from hep-ph)
Fluctuations of identified particle yields using the {\nu} dyn variable at energies available at the BNL Relativistic Heavy Ion Collider
Vivek Kumar Singh🇮🇳 · D. K. Mishra🇮🇳 · Zubayer Ahammed🇮🇳
We study the fluctuations of net-charge, net-pion, net-kaon and net-proton using $D$ -measure and $ν_{d y n}$ variables in heavy-ion jet interaction generator (HIJING), ultra-relativistic quantum molecular dynamics (UrQMD), and hadron resonance gas (HRG) model at different collision energies \sqsn. It has been observed that, the values of $D$ strongly dependent on $Δ η$ in HIJING and UrQMD models and independent in HRG model. The diffusion coefficients ( $σ$ ) of identified particles are estimated at various \sqsn. It is observed that, the $σ$ values are independent of collision energies but emphasizes the particle species dependence of diffusion coefficient in the QGP medium. This study provides a realistic baseline for comparison with the experimental data.
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1907.02850 [pdf]
PRC(2020)·6 citations

Affiliations

first authorsco-authorsvia INSPIRE

Skewness of the elliptic flow distribution in sNN​​​ = 5.02~TeV PbPb collisions from HYDJET++ model

Spectral control over γ-ray echo using a nuclear frequency comb system

Fluctuations of identified particle yields using the {\nu} dyn variable at energies available at the BNL Relativistic Heavy Ion Collider

Affiliations

Skewness of the elliptic flow distribution in $s_{_{NN}}$ = 5.02~TeV PbPb collisions from HYDJET++ model

Spectral control over $γ$ -ray echo using a nuclear frequency comb system