97 research outputs found
Methane production from ruminant livestock:Mitigation through dietary manipulation and application of the CO² method
Shear Viscosity of hadronic matter at finite temperature and magnetic field
We calculate the transport coefficient of hadronic matter in the presence of
temperature and magnetic field using the linear sigma model. In the relaxation
time approximation, we estimate the shear viscosity over entropy density
. The point-like interaction rates of hadrons are evaluated through the
-matrix approach in the presence of a magnetic field to obtain the
temperature and magnetic field-dependent relaxation time. We observe that the
transport coefficients are anisotropic in the presence of the magnetic field.
We calculate the temperature and magnetic field-dependent anisotropic shear
viscosity coefficients by incorporating the estimated relaxation time. The
value of viscosity over entropy density is lower in the presence of a magnetic
field than the value of it in a thermal medium. The behavior of the
perpendicular components of the shear viscosity coefficient is also discussed.
We consider the temperature-dependent hadron masses from mean-field effects in
this work.Comment: 20 pages, 3 figure
Neutral pion mass in warm magnetized medium within Linear Sigma Model coupled to Quarks framework
We study the neutral pion mass in the presence of an external arbitrary
magnetic field in the framework of the linear sigma model coupled to quark
(LSMq) at finite temperature. In doing so, we have calculated the pion
self-energy, constructed the dispersion equation via re-summation, and solved
the dispersion relation at zero three momentum limit. In calculating the pion
mass, we have included meson self-coupling's thermal and magnetic contribution
and approximate chiral order parameter . We report that the mass
decreases with the magnetic field and increases with temperature.Comment: 26 pages, 7 captioned figure
General structure of gauge boson propagator and its spectra in a hot magnetized medium
Based on transversality condition of gauge boson self-energy we have
systematically constructed the general structure of the gauge boson two-point
functions using four linearly independent basis tensors in presence of a
nontrivial background, i.e., hot magnetized material medium. The hard thermal
loop approximation has been used for the heat bath to compute various form
factors associated with the gauge boson's two point functions both in strong
and weak field approximation. We have also analyzed the dispersion of a gauge
boson (e.g., gluon) using the effective propagator both in strong and weak
magnetic field approximation. The formalism is also applicable to QED. The
presence of only thermal background leads to a longitudinal (plasmon) mode and
a two-fold degenerate transverse mode. In presence of a hot magnetized
background medium the degeneracy of the two transverse modes is lifted and one
gets three quasiparticle modes. In weak field approximation one gets two
transverse modes and one plasmon mode. On the other hand, in strong field
approximation also one gets the three modes in Lowest Landau Level. The general
structure of two-point function may be useful for computing the thermo-magnetic
correction of various quantities associated with a gauge boson.Comment: 39 pages, 7 figure
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