197490176
Membrane in M5-branes Background
In this paper, we investigate the properties of membrane in the M5-branes background. Through solving the classical equations of motion of membrane, we can understand the classical dynamics of membrane in this background.
118658801
Note on a noncritical holographic model with a magnetic field
We consider a noncritical holographic model constructed from an intersecting brane configuration D4 root D4-D4 with an external magnetic field. We investigate the influences of this magnetic field on strongly coupled dynamics by the gauge/gravity correspondence.
15827262
Note on Chiral Symmetry Breaking from Intersecting Branes
In this paper, we will consider the chiral symmetry breaking in the holographic model constructed from the intersecting brane configuration, and investigate the Nambu-Goldstone bosons associated with this symmetry breaking.
119105128
Vertex Operators of Open String States in the Intersecting D-brane World
Starting with a new bosonization scheme for the \beta\gamma CFT of the super-conformal ghosts, vertex operators are constructed for massless open string states in the intersecting D-brane world. These vertex operators satisfy all requirements for a consistent RNS formulation of superstring theories, so GSO projections can be properly taken.
100758194
Viscosity and Jet Quenching from a Holographic Model
6908824
NGN, QCD 2 and chiral phase transition from string theory
We construct a D2-D8-8 configuration in string theory, it can be described at low energy by two dimensional field theory. In the weak coupling region, the low energy theory is a nonlocal generalization of Gross-Neveu(GN) model which dynamically breaks the chiral flavor symmetry U(Nf)L × U(Nf)R at large Nc and finite Nf. However, in the strong coupling region, we can use the SUGRA/Born-Infeld approximation to describe the low energy dynamics of the system. Also, we analyze the low energy dynamics about the configuration of wrapping the one direction of D2 brane on a circle with anti-periodic boundary condition of fermions. The fermions and scalars on D2 branes get mass and decouple from the low energy theory. The IR dynamics is described by the QCD2 at weak coupling. In the opposite region, the dynamics has a holographic dual description. And we have discussed the phase transition of chiral symmetry breaking at finite temperature. Finally, after performing T-duality, this configuration is related to some other brane configurations.
119267787
Entropy relations of black holes with multihorizons in higher dimensions
We study the entropy relations of multihorizon black holes in higher dimensional (A)dS spacetime with maximal symmetries, including Einstein-Maxwell gravity and f(R)(-Maxwell) gravity. These additional equalities in thermodynamics are expected to be useful in understanding the origin of black hole entropy at the microscopic level. By revisiting the entropy product introduced by Cvetic et al., we see that in our case it has an unexpected behavior. It is shown that this electric charge Q plays an important role in this entropy product. The entropy product of charged black holes only depends on the electric charge Q and is mass independent. When Q vanishes in the solution, it becomes mass dependent, even when including the effect of the unphysical "virtual" horizons. In this sense, the "universal relation" of this entropy product is destroyed. Then we introduce another kind of "universal" entropy relation, which only depends on the cosmological constant. and the background topology k and does not depend on the conserved charges Q or even the mass M.
121151016
Higher-order-mode absorbers for energy recovery linac cryomodules at Brookhaven National Laboratory
Several future accelerator projects at Brookhaven for the Relativistic Heavy Ion Collider (RHIC) are based on energy recovery linacs (ERLs) with high-charge high-current electron beams. Their stable operation mandates effective higher-order-mode (HOM) damping. The development of HOM dampers for these projects is pursued actively at this laboratory. Strong HOM damping was experimentally demonstrated both at room and at superconducting (SC) temperatures in a prototype research and development (RD this will impose additional constraints and complications. This paper presents the results of simulations and measurements of several damper configurations.
118693623
Angular Reconstruction of a Lead Scintillating-Fiber Sandwiched Electromagnetic Calorimeter
The Neighbor Cell Deposited Energy Ratio (NCDER) is a new method that is proposed to reconstruct incidence position in a single layer for a 3-dimensional imaging electromagnetic calorimeter (ECAL). This method was applied to reconstruct the ECAL test beam data for the Alpha Magnetic Spectrometer-02 (AMS-02). The results show that this method can achieve an angular resolution of 7.36 +/- 0.08 degrees/root E circle plus 0.28 +/- 0.02 degrees in the determination of the photon's direction, which is much more precise than that obtained with the commonly-adopted Center of Gravity (COG) method (8.4 +/- 0.1 degrees/root E circle plus 0.8 +/- 0.3 degrees). Furthermore, since it uses only the properties of electromagnetic showers, this new method could also be used for other type of fine grain sampling calorimeters.
53137309
New class of rotating perfect fluid black holes in three dimensional gravity
We obtain a new class of rotating black holes for Einstein theory with perfect fluid source in $$(2+1)$$(2+1) dimensions. We conclude that these black hole solutions only depend on the variable of the angular velocity $$m(r)$$m(r). Some examples of these black holes are given explicitly. In particular, an unknown static black hole in this special background is obtained. In addition, the general properties including the horizon structure, energy conditions and equation of state, mass, and angular momentum are explained in detail.
4989491
The “universal property” of horizon entropy sum of black holes in four dimensional asymptotical (anti-)de-Sitter spacetime background
A bstractWe present a new “universal property” of entropy, that is the “entropy sum” relation of black holes in four dimensional (anti-)de-Sitter asymptotical background. They depend only on the cosmological constant with the necessary effect of the un-physical “virtual” horizon included in the spacetime where only the cosmological constant, mass of black hole, rotation parameter and Maxwell field exist. When there is more extra matter field in the spacetime, one will find the “entropy sum” is also dependent of the strength of these extra matter field. For both cases, we conclude that the “entropy sum” does not depend on the conserved charges M , Q and J , while it does depend on the property of background spacetime. We will mainly test the “entropy sum” relation in static, stationary black hole and some black hole with extra matter source (scalar hair and higher curvature) in the asymptotical (anti-)de-sitter spacetime background. Besides, we point out a newly found counter example of the mass independence of the ”entropy product” relation in the spacetime with extra scalar hair case, while the “entropy sum” relation still holds. These result are indeed suggestive to some underlying microscopic mechanism. Moreover, the cosmological constant and extra matter field dependence of the “entropy sum” of all horizon seems to reveal that “entropy sum” is more general as it is only related to the background field. For the case of asymptotical flat spacetime without any matter source, we give a note for the Kerr black hole case in appendix. One will find only mass dependence of “entropy sum” appears. It makes us believe that, considering the dependence of “entropy sum”, the mass background field may be regarded as the next order of cosmological constant background field and extra matter field. However, fully explaining the relationship between the “entropy sum” relation and background properties still requires further exploration.