8543665
PION AND KAON DISSOCIATION IN HOT QUARK MEDIUM
Pion and kaon dissociation in a medium of hot quark matter is studied in the Nambu–Jona-Lasinio model. The decay widths of pion and kaon are found to be large but finite at temperatures much higher than the so-called critical temperature of chiral or deconfinement transition, kaon decay width being larger. Consequently, pions and even kaons (with a lower density compared to pions) should coexist with quarks and gluons at such high temperatures. The implication of the above result in the study of quark–gluon plasma is discussed.
122920137
Tunneling in magnetic fields
Tunneling effects in external magnetic fields are discussed in the model problem of a charged particle on a vertical rotating circle in a uniform gravitational field. The magnetic fields used are the ones for the monopole and a certain solution that arises in the context of the classical Weinberg-Salam model. Using instanton methods and the Gaussian approximation, various consequences regarding the tunnelling amplitudes and the level splittings in the presence of magnetic fields are obtained.
118488028
Mesonic excitations of QGP: Study with an effective model
We study the correlations between quark-antiquark pairs in different quantum number channels in a deconfined plasma by using an effective model of QCD. Using the three flavor PNJL model, the finite temperature spectral functions for different mesonic states are studied at zero and nonzero quark chemical potentials. It is found that in the $\ensuremath{\eta}$ channel, resonance structures survive above the chiral transition temperature ${T}_{\ensuremath{\chi}}$, while the kaonic states seem to get washed off just above ${T}_{\ensuremath{\chi}}$. The sensitivity of the structures to the anomaly term are carefully investigated.
45361532
Hadron masses at finite density from the Zimanyi-Moskowski model.
118314565
Stability against {alpha} decay of some recently observed superheavy elements
The probability of {alpha}-particle emission for some recently observed superheavy nuclei (SHN) are investigated. The {alpha}-decay half-lives of SHN are calculated in a quantum tunneling model with density-dependent M3Y (DDM3Y) effective nuclear interaction using theoretical and measured Q{sub {alpha}} values. We determine the density distribution of {alpha} and daughter nuclei from the relativistic mean-field (RMF) theory using FSUGold force, NL3, and TM1 parameter sets. The double-folded nuclear potential is numerically calculated in a more microscopic manner using these density distributions. The estimated values of {alpha}-decay half-lives are in good agreement with the recent data. We compare our results with recently detected {alpha}-decay chains from a new element with atomic number Z=117 reported by the Joint Institute for Nuclear Research, Dubna. Finally, we determine the half-lives of superheavy elements with Z=108-120 and neutron number N=152-190 to explore the long-standing predictions of the existence of an 'island of stability' due to possible spherical proton (Z{approx}114) and neutron (N{approx}184) shell closures.
119271298
On the possibility of rho-meson condensation in neutron stars
The possibility of meson condensation in stars and in heavy-ion collisions has been discussed in the past. Here, we study whether rho meson condensation ($\rho^{-}$) can occur in very dense matter and determine the effect of strong magnetic fields on this condensation. We find that rho meson condensates can appear in the core of the neutron star assuming a rho mass which is reduced due to in-medium effects. We find that the magnetic field has a non-negligible effect in triggering condensation.
41364893
On entanglement entropy functionals in higher-derivative gravity theories
A bstractIn arXiv:1310.5713 [1] and arXiv:1310.6659 [2] a formula was proposed as the entanglement entropy functional for a general higher-derivative theory of gravity, whose lagrangian consists of terms containing contractions of the Riemann tensor. In this paper, we carry out some tests of this proposal. First, we find the surface equation of motion for general four-derivative gravity theory by minimizing the holographic entanglement entropy functional resulting from this proposed formula. Then we calculate the surface equation for the same theory using the generalized gravitational entropy method of arXiv:1304.4926 [3]. We find that the two do not match in their entirety. We also construct the holographic entropy functional for quasi-topological gravity, which is a six-derivative gravity theory. We find that this functional gives the correct universal terms. However, as in the R2 case, the generalized gravitational entropy method applied to this theory does not give exactly the surface equation of motion coming from minimizing the entropy functional.
27271627
Attractive holographic c-functions
A bstractUsing the attractor mechanism for extremal solutions in N=2$$ \mathcal{N}=2 $$ gauged supergravity, we construct a c-function that interpolates between the central charges of theories at ultraviolet and infrared conformal fixed points corresponding to anti-de Sitter geometries. The c-function we obtain is couched purely in terms of bulk quantities and connects two different dimensional CFTs at the stable conformal fixed points under the RG flow.