20,726 research outputs found
Multiplicity fluctuations in heavy-ion collisions using canonical and grand-canonical ensemble
We report the higher order cumulants and their ratios for baryon, charge and
strangeness multiplicity in canonical and grand-canonical ensembles in ideal
thermal model including all the resonances. When the number of conserved quanta
is small, an explicit treatment of these conserved charges is required, which
leads to a canonical description of the system and the fluctuations are
significantly different from the grand canonical ensemble. Cumulant ratios of
total charge and net-charge multiplicity as a function of collision energies
are also compared in grand canonical ensemble.Comment: 7 pages, 5 Figs, Published versio
A Variational Approach to Bound States in Quantum Field Theory
We consider here in a toy model an approach to bound state problem in a
nonperturbative manner using equal time algebra for the interacting field
operators. Potential is replaced by offshell bosonic quanta inside the bound
state of nonrelativistic particles. The bosonic dressing is determined through
energy minimisation, and mass renormalisation is carried out in a
nonperturbative manner. Since the interaction is through a scalar field, it
does not include spin effects. The model however nicely incorporates an
intuitive picture of hadronic bound states in which the gluon fields dress the
quarks providing the binding between them and also simulate the gluonic content
of hadrons in deep inelastic collisions.Comment: latex, revtex, 22 page
Vacuum structure and effective potential at finite temperature: a variational approach
We compute the effective potential for theory with a squeezed
coherent state type of construct for the ground state. The method essentially
consists in optimising the basis at zero and finite temperatures. The gap
equation becomes identical to resumming the infinite series of daisy and super
daisy graphs while the effective potential includes multiloop effects and
agrees with that obtained through composite operator formalism at finite
temperature.Comment: 15 pages, Revtex, No figures, to appear in Jou. of Phys.G(Nucl. and
Part. Phys.
Sirenomelia: Case Report and Discussion of its Prenatal Diagnosis
Sirenomelia is a rare polymalformative, lethal congenital anomaly, characterized by fusion of both lower limbs, bilateral renal agenesis, absent external genitalia, aberrant fetal vasculature, and severe oligohydramnios. We hereby report a case of Sirenomelia diagnosed postnatally in an unbooked pregnancy presenting at the thirty‑fifth gestational week.Keywords: Diabetes mellitus, dysmorphic lower limb, prenatal diagnosis, sirenomeli
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