Charmonium decay widths in magnetized matter

We study the partial decay widths of the charmonium states ($J/\psi$, $\psi(3686)$, $\psi(3770)$, $\chi_{c0}$, $\chi_{c2}$) to $D\bar D$ ($D^+D^-$ or $D^0\bar {D^0}$) in isospin asymmetric nuclear matter, in the presence of strong magnetic fields. The in-medium partial decay widths of charmonium states to $D\bar D$ are calculated within a light quark--antiquark pair creation model, namely the $^3P_0$ model, using the in--medium masses of the charmonia as well as $D$ and $\bar D$ mesons in the magnetized nuclear matter obtained within a chiral effective model. The presence of a magnetic field leads to Landau quantization of the energy levels of the proton in the nuclear medium. The effects of magnetic field and isospin asymmetry on the charmonium decay widths to $D\bar D$ are found to be quite prominent. The effects of the anomalous magnetic moments have also been taken into consideration for obtaining the in-medium masses of these heavy flavour mesons, used to calculate the partial decay widths of the charmonium states. The medium modifications of the charmonium decay widths can have observable consequences on the production of the charmed mesons in high energy asymmetric heavy ion collision experiments.Comment: 29 pages, 8 figures, to be published in Eur. Phys. Jour. A. arXiv admin note: text overlap with arXiv:1803.04322, arXiv:1901.06259, arXiv:1807.07572, arXiv:1811.04622, arXiv:1801.0640

A study of feto-maternal outcome in case of premature rupture of membrane at a tertiary care center

Background: Premature rupture of membranes is the rupture of the fetal membranes in the absence of uterine contraction or before the onset of labor. When this occurs before 37 weeks of gestation, it is termed as preterm premature rupture of membranes. Management depends upon gestational age and the presence of complicating factors. An accurate assessment of gestational age and knowledge of the maternal, fetal and neonatal risks are essential to appropriate evaluation, counselling, and care of patients with PROM. The purpose of the study is timely diagnosis and appropriate management of the cases of PROM and PPROM to improve maternal and neonatal outcomes. Methods: A Prospective study was performed at the department of obstetrics and gynecology, at a tertiary care center from August 2020 to December 2021. A clinical data sheet was made for recording all information about the pregnant women after taking their consent. And their maternal and neonatal outcomes were recorded. Results: a total of 150 cases of PROM and PPROM were taken during our study out of which 53.33% belong to the younger age group, 43.33% were primi gravida, 66.66% belonged to the lower socioeconomic class, 25.33% had a previous history of abortion followed by dilatation and evacuation, rate of cesarean delivery was 34.66% and rate of NICU admission of neonates was 15.78% and 57.87% babies had low birth weight and rate of stillbirth was 1.97%. whereas 34.66% of cases had various complications related to PROM. Conclusions: Individualized management of PROM cases depending on the gestational age and risk of complications and antibiotic coverage is the best way to achieve a good fetomaternal outcome

Superspace formulation in the absence of full anti-BRST symmetry

There are two known approaches to construct the six-dimensional superspace formulation of a gauge theory where the additional two dimensions are Grassmannian. One of the approaches (the second approach in this paper) requires both BRST and anti-BRST symmetries for the superspace formulation. In this paper, we consider an effective theory in a recently introduced quadratic gauge which has two pairs of ghosts. The theory does not have a full anti-BRST symmetry and only has full BRST symmetry. We show that it is possible to partially formulate this effective theory in the superspace using the second approach even in the absence of full anti-BRST symmetry due to the peculiar structure of the theory. We encounter a couple of technical difficulties which further brings useful insights

Search for Abelian dominance in the effective SO(N) theory

Recently a new quadratic gauge has been introduced in the SU(N) QCD in which interesting non perturbative characteristics of QCD has been brought to light. One of the characteristics is Abelian dominance, which is one of the signatures of color confinement in a dual superconductor picture. The SO(N) QCD has been used quite often for various studies. In this paper, we extend the application of the quadratic gauge to SO(N) QCD and probe different vacua of the effective theory in which ghosts condense to search existence of Abelian dominance. We begin with the vacuum whose SU(N) group version leads us to find the evidence of Abelian dominance in SU(N) QCD. Contrary to expectation, we do not observe Abelian dominance in such vacuum here. Taking hint from this consequence, another vacuum is then examined in which existence of Abelian dominance is strongly indicated. The geometric explanation for the results in both the vacua has been provided. Keywords: Quadratic gauge, SO(N) effective theory, Abelian dominance, Color confinemen

Absence of the Gribov ambiguity in a quadratic gauge

The Gribov ambiguity exists in various gauges. Algebraic gauges are likely to be ambiguity free. However, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. In addition, they are not generally compatible with the boundary conditions on the gauge fields, which are needed to compactify the space i.e., the ambiguity continues to exist on a compact manifold. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We consider an example of a spherically symmetric gauge field configuration in which we prove that this Lorentz invariant gauge removes the ambiguity on a compact manifold $$\mathbb {S}^3$$, when a proper boundary condition on the gauge configuration is taken into account. Thus, we provide one example where the ambiguity is absent on a compact manifold in the algebraic gauge. We also show that the BRST invariance is preserved in this gauge