Correlation of high energy muons with primary composition in extensive air shower

An experimental investigation of high energy muons above 200 GeV in extensive air showers has been made for studying high energy interaction and primary composition of cosmic rays of energies in the range 10 to the 14th power approx. 10 to the 15th power eV. The muon energies are estimated from the burst sizes initiated by the muons in the rock, which are measured by four layers of proportional counters, each of area 5 x 2.6 sq m, placed at 30 m.w.e. deep, Funasaka tunnel vertically below the air shower array. These results are compared with Monte Carlo simulations based on the scaling model and the fireball model for two primary compositions, all proton and mixed

Superconductivity at 5.2 K in ZrTe3 polycrystals and the effect of Cu, Ag intercalation

We report the occurrence of superconductivity in polycrystalline samples of ZrTe3 at 5.2 K temperature at ambient pressure. The superconducting state coexists with the charge density wave (CDW) phase, which sets in at 63K. The intercalation of Cu or Ag, does not have any bearing on the superconducting transition temperature but suppresses the CDW state. The feature of CDW anomaly in these compounds is clearly seen in the DC magnetization data. Resistivity data is analysed to estimate the relative loss of carriers and reduction in the nested Fermi surface area upon CDW formation in the ZrTe3 and the intercalated compounds.Comment: 5 pages, 8 figure

Triple-labeled Whole-body Autoradiography of Tumor Bearing Rat using 18F-FDG, 67Ga-Citrate and 75Se-Selenomethionine

開始ページ、終了ページ: 冊子体のページ付

Confined Phase In The Real Time Formalism And The Fate Of The World Behind The Horizon

In the real time formulation of finite temperature field theories, one introduces an additional set of fields (type-2 fields) associated to each field in the original theory (type-1 field). In hep-th/0106112, in the context of the AdS-CFT correspondence, Maldacena interpreted type-2 fields as living on a boundary behind the black hole horizon. However, below the Hawking-Page transition temperature, the thermodynamically preferred configuration is the thermal AdS without a black hole, and hence there are no horizon and boundary behind it. This means that when the dual gauge theory is in confined phase, the type-2 fields cannot be associated with the degrees of freedom behind the black hole horizon. I argue that in this case the role of the type-2 fields is to make up bulk type-2 fields of classical closed string field theory on AdS at finite temperature in the real time formalism.Comment: v2: cases divided into sections with more detailed explanations. considerably enlarged with examples and a lot of figures. sec 4.1.2 for general closed cut-out circuits and appendix A for a sample calculation newly added. many minor corrections and clarifying comments. refs added. v3: refs and related discussion added. 1+46 pages, 26 figures. published versio

On the entropy operator for the general SU(1,1) TFD formulation

In this letter, an entropy operator for the general unitary SU(1,1) TFD formulation is proposed and used to lead a bosonic system from zero to finite temperature. Namely, considering the closed bosonic string as the target system, the entropy operator is used to construct the thermal vacuum. The behaviour of such a state under the breve conjugation rules is analized and it was shown that the breve conjugation does not affect thermal effects. From this thermal vacuum the thermal energy, the entropy and the free energy of the closed bosonic string are calculated and the apropriated thermal distribution for the system is found after the free energy minimization.Comment: 13 pages, revtex4, minor typos corrected, references adde

Entanglement and entropy operator for strings in pp-wave time dependent background

In this letter new aspects of string theory propagating in a pp-wave time dependent background with a null singularity are explored. It is shown the appearance of a 2d entanglement entropy dynamically generated by the background. For asymptotically flat observers, the vacuum close to the singularity is unitarily inequivalent to the vacuum at $\tau = -\infty$ and it is shown that the 2d entanglement entropy diverges close to this point. As a consequence, the positive time region is inaccessible for observers in $\tau =-\infty$. For a stationary measure, the vacuum at finite time is seen by those observers as a thermal state and the information loss is encoded as a heat bath of string states.Comment: revtex4, 15 pages, revised version to appear in Physics Letters

Space-time translational gauge identities in Abelian Yang-Mills gravity

We derive and calculate the space-time translational gauge identities in quantum Yang-Mills gravity with a general class of gauge conditions involving two arbitrary parameters. These identities of the Abelian group of translation are a generalization of Ward-Takahasi-Fradkin identities and important for general discussions of possible renormalization of Yang-Mills gravity with translational gauge symmetry. The gauge identities in Yang-Mills gravity with a general class of gauge conditions are substantiated by explicit calculations.Comment: 15 pages. To be published in The European Physical Journal - Plus (2012

Black Hole Thermodynamics in Horava Lifshitz Gravity and the Related Geometry

Recently, Ho$\breve{r}$ava proposed a non-relativistic renormalizable theory of gravity which is essentially a field theoretic model for a UV complete theory of gravity and reduces to Einstein gravity with a non-vanishing cosmological constant in IR. Also the theory admits a Lifshitz scale-invariance in time and space with broken Lorentz symmetry at short scale. On the other hand, at large distances higher derivative terms do not contribute and the theory coincides with general relativity. Subsequently, Cai and his collaborators and then Catiuo et al have obtained black hole solutions in this gravity theory and studied the thermodynamic properties of the black hole solution. In the present paper, we have investigated the black hole thermodynamic for two choices of the entropy function - a classical and a topological in nature. Finally, it is examined whether a phase transition is possible or not.Comment: 8 figure