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The in-medium partial decay widths of $Upsilon (4S) rightarrow Bbar B$ in magnetized asymmetric nuclear matter are studied using a field theoretic model for composite hadrons with quark/antiquark constituents. The medium modifications of the decay widths of $Upsilon (4S)$ to $Bbar B$ pair in magnetized matter, arise due to the mass modifications of the decaying $Upsilon (4S)$ as well as of the produced $B$ and $bar B$ mesons. The effects of the anomalous magnetic moments for the proton and neutron are taken into consideration in the present investigation. The presence of the external magnetic field is observed to lead to different mass modifications within the $B (B^+, B^0)$ as well as the $bar B (B^-, bar {B^0})$ doublets, even in isospin symmetric nuclear matter, due to the difference in the interactions of the proton and the neutron to the electromagnetic field. This leads to difference in the upsilon decay widths to the neutral ($B^0 bar {B^0}$) and the charged ($B^+ B^-$) pairs in the magnetized symmetric nuclear matter. The isospin asymmetry is observed to lead to quite different behaviours for the $Upsilon (4S)$ decay widths to the charged and neutral $Bbar B$. In the presence of the magnetic field, the Landau level contributions give rise to positive shifts in the masses of the charged $B$ and $bar B$ mesons. This leads to the decay of $Upsilon(4S)$ to the charged $B^+ B^-$ to be suppressed as compared to the neutral $Bbar B$ pair, especially at low densities. This may lead to suppression in the production of the charged $B^pm$ mesons as compared to the neutral $B^0$ and $bar {B^0}$ mesons at LHC and RHIC.
We study the partial decay widths of the charmonium states ($J/psi$, $psi(3686)$, $psi(3770)$, $chi_{c0}$, $chi_{c2}$) to $Dbar D$ ($D^+D^-$ or $D^0bar {D^0}$) in isospin asymmetric nuclear matter, in the presence of strong magnetic fields. The in-me
The medium modifications of the open charm mesons ($D$ and $bar D$) are studied in isospin asymmetric nuclear matter in the presence of strong magnetic fields, using a chiral effective model. The mass modifications of these mesons in the effective ha
The decay widths of the charmonium states to $Dbar D$ in isospin asymmetric nuclear matter in the presence of a magnetic field are studied, using a field theoretical model for composite hadrons with quark/antiquark constituents. The medium modificati
The existence of phase transitions from liquid to gas phases in asymmetric nuclear matter (ANM) is related with the instability regions which are limited by the spinodals. In this work we investigate the instabilities in ANM described within relativi
The quark-meson-coupling model is used to study droplet formation from the liquid-gas phase transition in cold asymmetric nuclear matter. The critical density and proton fraction for the phase transition are determined in the mean field approximation