We study the in-medium properties of $D$ and $\bar{D}$ mesons in isospin asymmetric hyperonic matter arising due to their interactions with the light hadrons. The interactions of $D$ and $\bar{D}$ mesons with these light hadrons are derived by generalizing the chiral SU(3) model used for the study of hyperonic matter to SU(4). The nucleons, the scalar isoscalar meson, $σ$ and the scalar-isovector meson, $δ$ as modified in the strange hadronic matter, modify the masses of $D$ and $\bar{D}$ mesons. It is found that as compared to the $\bar{D}$ mesons, the $D$ meson properties are more sensitive to the isospin asymmetry at high densities. The effects of strangeness in the medium on the properties of $D$ and $\bar{D}$ mesons are studied in the present investigation. The $D$ mesons ($D^0$,$D^+$) are found to undergo larger medium modifications as compared to $\bar{D}$ mesons ($\bar {D^0}$, $D^-$) with the strangeness fraction, $f_s$ and these modifications are observed to be more appreciable at high densities. The present study of the in-medium properties of $D$ and $\bar{D}$ mesons will be of relevance for the experiments in the future Facility for Antiproton and Ion Research, GSI, where the baryonic matter at high densities will be produced. The isospin asymmetric effects in the doublet $D = (D^{0}, D^{+})$ in the strange hadronic matter should show in observables like their production and flow in asymmetric heavy-ion collisions as well as in $J/ψ$ suppression.
We compare relativistic mean field models with their low density expansion counterparts used to mimic non-relativistic models by consistently expanding the baryonic scalar density in powers of the baryonic number density up to ${\cal O}(13/3)$, which goes two orders beyond the order considered in previous works. We show that, due to the non-trivial density dependence of the Dirac mass, the convergence of the expansion is very slow, and the validity of the non-relativistic approximation {\bf is} questionable even at subsaturation densities. In order to analyze the roles played by strangeness an…
In this work, we discuss the deconfinement phase transition to quark matter in hot/dense matter. We {examine} the effect that different charge fractions, isospin fractions, net strangeness, and chemical equilibrium with respect to leptons have on the position of the coexistence line between different phases. In particular, we investigate how different sets of conditions that describe matter in neutron stars and their mergers, or matter created in heavy-ion collisions affect the position of the critical end point, namely where the first-order phase transition becomes a crossover. We also presen…
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 qua…
In this work, we examine in detail the difference between constraining the electric charge fraction and isospin fraction when calculating the deconfinement phase transition in the presence of net strangeness. We present relations among charge and isospin fractions and the corresponding chemical potentials and draw 3-dimensional QCD phase diagrams for matter out of weak equilibrium. Finally, we briefly discuss how our results can be applied to comparisons of matter created in heavy ion collisions and binary neutron star mergers.
The production of strange particles (kaons, hyperons) and hypernuclei in light charged particle induced reactions in the energy range of a few GeV (2-15 GeV) has become a topic of active research in several facilities (e.g., HypHI and PANDA at GSI and/or FAIR (Germany), JLab (USA), and JPARC (Japan)). This energy range represents the low-energy limit of the string models (degree of freedom: quark and gluon) or the high-energy limit of the so-called spallation models (degree of freedom: hadrons). A well known spallation model is INCL, the Liège intranuclear cascade model (combined with a de-exc…
We study the medium modifications of the spectral functions as well as production cross-sections of the strange vector mesons ($ϕ$, $K^*$ and $\bar {K^*}$) in isospin asymmetric strange hadronic matter. These are obtained from the in-medium masses of the open strange mesons and the decay widths $ϕ\rightarrow K\bar K$, $K^* \rightarrow Kπ$ and $\bar {K^*} \rightarrow {\bar K}π$ in the hadronic medium. The decay widths are computed using a field theoretic model of composite hadrons with quark/antiquark constituents, from the matrix element of the light quark-antiquark pair creation term of the f…
We extend our previous study on the decay behavior of $P_c$ hadronic molecules to their strange and beauty partners. While $P_c(4380)$ and $P_c(4450)$ locate just below the $\bar DΣ_c^*$ and $\bar D^*Σ_c$ thresholds, respectively, their proposed strange partners $N(1875)$ and $N(2080)$ sit just below the $KΣ^*$ and $K^*Σ$ thresholds, respectively. Using the effective Lagrangian approach as the same as for the study of $P_c$ hadronic molecular states and with the couplings determined by the $\mathrm{SU}(3)$ flavor symmetry, the decay patterns of $N(1875)$ and $N(2080)$ are obtained assuming the…
The in-medium mass and decay width of the $ϕ$ meson in the hot asymmetric strange hadronic matter are calculated using an effective Lagrangian approach for $ϕ$ $K\bar K$ interaction. The in-medium contributions of $K \bar K$ loop to the $ϕ$ meson self-energy are computed by the medium modified kaon and antikaon mass which is evaluated using the chiral SU(3) model. To deal with the ultraviolet divergence, we regularize the loop integral of self-energy with a dipole form factor, and present the results for cut-off mass, $Λ_c$=3 GeV. In chiral model calculations, for strange matter, we find that …
The total binding energy of compact stars is the sum of the gravitational binding energy $(BE)_g$ and the nuclear binding energy $(BE)_n$, the last being related to the microphysics of the interactions. While the first is positive (binding) both for hadronic stars and for strange quark stars, the second is large and negative for hadronic stars (anti-binding) and either small and negative (anti-binding) or positive (binding) for strange quark stars. A hadronic star can convert into a strange quark star with a larger radius because the consequent reduction of $(BE)_g$ is over-compensated by the …
我们提出了选定的结果奇怪的和重味介子在热的和致密的核介质中的属性,强调在自洽耦合通道方法的基础上的手征拉格朗日。在奇异性部分,我们讨论了如何在FAIR条件下的光奇异矢量的增强反应性可以绑定到其主要衰变模式(例如$\bar K^*\to\bar K π$)的介质效应和矢量介子核子相互作用中的奇异重子的激发。在重味部分,我们集中在最近的测定的粲介子和底介子的输运系数的强子气体在重子化学势为零。我们评论微观输运模拟的作用,建立从重离子碰撞的理论模型和实验观测之间的联系。
We consider three-flavor chiral perturbation theory ($χ$PT) at zero temperature and nonzero isospin ($μ_{I}$) and strange ($μ_{S}$) chemical potentials. The effective potential is calculated to next-to-leading order (NLO) in the $π^{\pm}$-condensed phase, the $K^{\pm}$-condensed phase, and the $K^0/\bar{K}^0$-condensed phase. It is shown that the transitions from the vacuum phase to these phases are second order and take place when, $|μ_I|=m_π$, $|{1\over2}μ_I+μ_S|=m_K$, and $|-{1\over2}μ_I+μ_S|=m_K$, respectively at tree level and remains unchanged at NLO. The transition between the two conde…
The LHCb Collaboration announced the observation of three narrow structures consistent with hidden-charm pentaquark states. They are candidates of hadronic molecules formed of a pair of a charmed baryon and an anticharmed meson. Among them, the $P_c(4457)$ mass is consistent with earlier predictions of a $Σ_c\bar D^*$ molecule with $I=1/2$. We point out that if such a picture were true, one would have $\mathcal{B}(P_c(4457)\to J/ψΔ^+)/\mathcal{B}(P_c(4457)\to J/ψp)$ at the level ranging from a few percent to about 30%. Such a large isospin breaking decay ratio is two to three orders of magnitu…