Nuclear Theory·nucl-th

Thursday·November 28, 2019

13 papers—8 primary·5 cross-listed

09
Light (anti-)nuclei and (anti-)hypertriton production in $pp$ collisions at $s = 0.90, 2.76$ and $7$ TeV
Nserdin A. Ragab🇨🇳 · Zhi-Lei She🇨🇳 · Gang Chen🇨🇳
Production of light (anti-)nuclei and (anti-)hypertriton within midrapidity ( $∣ y ∣ < 0.5$ ) and $p_{T} < 3.0$ GeV/c in $pp$ interactions at $s$ = 0.90, 2.76 and 7 TeV is investigated by the dynamically constrained phase space coalescence model (DCPC), combined with {\footnotesize{PACIAE}} model. The ALICE data for yields, ratios, as well as transverse momentum distributions of $d$ and $d$ are well reproduced by the model simulations, meanwhile the three basic characters of $^{3} He$ , $^{3} He$ , $_{Λ}^{3} H$ , and $_{Λ}^{3} H$ are also predicted. Besides, we found the yields of light (anti-)nuclei produced are dependent upon their mass number $A$ , namely, their yields sharply decrease with the increasing of $A$ . The strangeness population factor $s_{3} = (_{Λ}^{3} H /^{3} He) / (Λ/p)$ is found to be about 0.7 $\sim$ 0.8, and is comparable with the available experimental results.
↳ hep-phnucl-thEur.Phys.J.Plus(2020)·5 citations
10
Infrared renormalon effects in color dipole TMD PDF at small- $x$
Nahid Vasim🇮🇳 · Raktim Abir🇮🇳
The uncertainties from the infrared renormalons in the (color dipole) gluon distribution is estimated. It is shown that non-linear saturation effects at small- $x$ shift the first IR pole at the Borel plane from $2/ β_{2}$ to $1/ β_{2}$ . As a consequence the estimated uncertainty is found to be $O (Λ_{QCD}^{2})$ instead of $O (Λ_{QCD}^{4})$ .
↳ hep-phhep-thnucl-thNPB(2020)·1 citation
11
Quark condensate seesaw mechanism for neutrino mass
A. Babič🇨🇿 · S. Kovalenko🇨🇱 · M. I. Krivoruchenko🇷🇺 · F. Šimkovic🇨🇿
We study a mechanism of generation of Majorana neutrino mass due to spontaneous breaking of chiral symmetry (SBCS) accompanied by the formation of a quark condensate. The effect of the condensate is transmitted to the neutrino sector via Lepton-Number Violating (LNV) lepton-quark dimension- $7$ operators known in the literature as an origin of the neutrino-mass-independent mechanism of neutrinoless double-beta ( $0 ν β β$ ) decay. The smallness of neutrino masses is due to a large ratio between the LNV scale and the scale of the SBCS. This is a new realization of the seesaw mechanism, which we dub the Quark Condensate SeeSaw (QCSS). We examine the predictions of the QCSS for $0 ν β β$ -decay and neutrino mass spectrum. We will show that our model predicts the normal neutrino mass ordering and narrow ranges of the neutrino masses.
↳ hep-phnucl-thPRD(2021)·10 citations
12
Exploring the QCD phase diagram via reweighting from isospin chemical potential
Bastian B. Brandt🇩🇪 · Francesca Cuteri🇩🇪 · Gergely Endrodi🇩🇪 · Sebastian Schmalzbauer🇩🇪
We investigate the QCD phase diagram for small values of baryon and strange quark chemical potentials from simulations at non-zero isospin chemical potential. Simulations at pure isospin chemical potential are not hindered by the sign problem and pion condensation can be observed for sufficiently large isospin chemical potentials. We study how the related phase boundary evolves with baryonic and strange chemical potentials via reweighting in quark chemical potentials and discuss our results. Furthermore, we propose and implement an alternative method to approach nonzero baryon (and strange quark) chemical potentials. This method involves simulations where physical quarks are paired with auxiliary quarks in unphysical "isospin" doublets and a decoupling of the auxiliary quarks by mass reweighting.
↳ hep-lathep-phnucl-thPoS(2019)·10 citations
13
Evading the model sign problem in the PNJL model with repulsive vector-type interaction via path optimization
Akira Ohnishi🇯🇵 · Yuto Mori🇯🇵 · Kouji Kashiwa🇯🇵
We discuss the sign problem in the Polyakov loop extended Nambu--Jona-Lasinio model with repulsive vector-type interaction by using the path optimization method. In this model, both of the Polyakov loop and the vector-type interaction cause the model sign problem, and several prescriptions have been utilized even in the mean field treatment. In the path optimization method, integration variables are complexified and the integration path (manifold) is optimized to evade the sign problem, or equivalently to enhance the average phase factor. Within the homogeneous field ansatz, the path is optimized by using the feedforward neural network. We find that the assumptions adopted in previous works, $Re A_{8} ≃ 0$ and $Re ω ≃ 0$ , can be justified from the Monte-Carlo configurations sampled on the optimized path. We also derive the Euler-Lagrange equation for the optimal path to satisfy. The two optimized paths, the solution of the Euler-Lagrange equation and the variationally optimized path, agree with each other in the region with large statistical weight.
↳ hep-lathep-phnucl-thPoS(2019)·1 citation

Affiliations

first authorsco-authorsvia INSPIRE

Light (anti-)nuclei and (anti-)hypertriton production in pp collisions at s​=0.90,2.76 and 7 TeV

Infrared renormalon effects in color dipole TMD PDF at small-x

Quark condensate seesaw mechanism for neutrino mass

Exploring the QCD phase diagram via reweighting from isospin chemical potential

Evading the model sign problem in the PNJL model with repulsive vector-type interaction via path optimization

Affiliations

Light (anti-)nuclei and (anti-)hypertriton production in $pp$ collisions at $s = 0.90, 2.76$ and $7$ TeV

Infrared renormalon effects in color dipole TMD PDF at small- $x$