Energy and Stability in Einstein-{Gauss-Bonnet} Models
A unified energy expression for Einstein-Gauss-Bonnet gravity, valid about the model's two distinct vacua, is obtained. It reduces to the usual Einstein form about a flat background, but about an anti-de Sitter vacuum it becomes that appropriate to a ghost Einstein theory with a cosmological term. Linearisation instability about the latter and general stability about the former are deduced by energy considerations, in agreement with previous results.

title: A Possible Black Hole Background in c=1 Matrix Model
abstract: We propose a new space-time interpretation for c=1 matrix model with potential $V(x)=-x^{2}/2-\m^{2}/2x^{2}$. It is argued that this particular potential corresponds to a black hole background. Some related issues are discussed.

title: THE EFFECTIVE LAGRANGIAN OF THREE DIMENSIONAL QUANTUM CHROMODYNAMICS
abstract: We consider the low energy limit of three dimensional quantum chromodynamics (QCD) with an even number of flavors. We show that parity is not spontaneously broken, but the global (flavor) symmetry is spontaneously broken. The low energy effective Lagrangian is a nonlinear sigma model on the Grassmannian. Some Chern-Simons terms are necessary in the Lagrangian to realize the discrete symmetries correctly. We consider also another parametrization of the low energy sector which leads to a three dimensional analogue of the Wess-Zumino-Witten-Novikov model. Since three dimensional QCD is believed to be a model for quantum antiferromagnetism, our effective Lagrangian can describe their long wavelength excitations (spin waves).

title: Asymptotic Freedom and Dirichlet String Theory
abstract: Fixed angle scattering at high energy in a string theory with boundaries satisfying Dirichlet conditions (Dirichlet strings) in D = 4 is shown to have logarithmic dependence on energy, in addition to the power-like behavior known before. High temperature free energy also depends logarithmically on temperature. Such a result could provide a matching mechanism between strings at long distance and asymptotic freedom at short distance, which is necessary for the reformulation of large-N QCD as a string theory. In order to reformulate the large-N QCD  as a string theory, assuming it is possible at all, we must find a string theory that contains only massive excitations (for pure QCD) and shares the characteristic features of asymptotic freedom, such as partonic behavior and logarithmic violation of scaling at high energy. The critical string theories we are mostly familiar with fail to meet theses two requirements: they contain massless gravitons and massless Yang-Mill particles, and fixed angle scattering falls off exponentially with total energy. Liouville theory [2] has been argued to be irrelevant for the problem of QCD , meanwhile the effective string picture advocated in , which without doubt is correct for long strings, has problems at short distances. Rigid strings  at first sight seem to give the right behavior at high energy and high temperature, but they have the wrong sign of free energy at high temperature as compared with QCD [6], and furthermore there are problems with unitarity [7]. Another simple yet non-trivial modification of short distance behavior of strings is to add world-sheet boundaries satisfying Dirichlet boundary conditions – each boundary is mapped to a single point in space-time and the position is then integrated over. Such a theory was originally proposed as an off-shell extension of closed string amplitudes . Meanwhile the point-like states of the Dirichlet boundaries were proven to produce powerlike behavior of fixed angle scattering at high energy [9]. The point-like structure was then linked to partons. Developments of the Dirichlet string theory in modern language can be found in . Recently Green [11] points out that at high temperature the Dirichlet boundaries produce a free energy similar to that of the large-N QCD found by Polchinski[6]. Namely, in QCD the free energy of a long string per unit length goes as μQCD(β)/L 2 ∼ − (β)N π2β4 , (1)

title: A remark on conformal anomaly and extrinsic geometry of random surfaces
abstract: In low dimensions, conformal anomaly has a profound influence on the critical behavior of random surfaces with extrinsic curvature rigidity 1/ α . We illustrate this by making a small D expansion of rigid random surfaces, where a non-trivial infrared fixed point is shown to exist. We speculate on the renormalization group flow diagram in the (α, D ) plane. We argue that the qualitative behavior of numerical simulations in D =3,4 could be understood on the basis of the phase diagram.

title: Magnetic Fields and Passive Scalars in Polyakov's Conformal Turbulence
abstract: Polyakov has suggested that two-dimensional turbulence might be described by a minimal model of conformal field theory. However, there are many minimal models satisfying the same physical inputs as Polyakov's solution (2, 21). Dynamical magnetic fields and passive scalars pose different physical requirements. For large magnetic Reynolds number other minimal models arise. The simplest one, (2, 13), makes reasonable predictions that may be tested in the astrophysical context. In particular, the equipartition theorem between magnetic and kinetic energies does not hold: the magnetic one dominates at larger distances.

title: Study of beauty hadron decays into pairs of charm hadrons
abstract: First observations of the decays Λb 0 → Λc +D(s) - are reported using data corresponding to an integrated luminosity of 3fb-1 collected at 7 and 8 TeV center-of-mass energies in proton-proton collisions with the LHCb detector. In addition, the most precise measurement of the branching fraction B(Bs 0→D+Ds -) is made and a search is performed for the decays B(s) 0→Λc +Λc -. The results obtained are B(Λb 0→Λc +D-)/ B(Λb 0→Λc +D s -)=0.042±0.003(stat)±0.003(syst), [B(Λb 0→Λc +D s -)/B(B0→D+D s -)]/[B(Λb 0→Λ c +π-)/B(B0→D +π-)]=0.96±0.02(stat)±0.06(syst),B(B s 0→D+Ds -)/ B(B0→D+Ds -)=0. 038±0.004(stat)±0.003(syst),B(B0→Λ c +Λc -)/B(B , B(Bs 0→Λc +Λ c -)/B(Bs 0→D+D s -)<0.30[95%C.L.]. Measurement of the mass of the Λb 0 baryon relative to the B0 meson gives M(Λb 0)-M(B0)=339. 72±0.24(stat)±0.18(syst)MeV/c2. This result provides the most precise measurement of the mass of the Λb 0 baryon to date.

title: Performance study of a GEM-TPC prototype using cosmic rays
abstract: Time projection chambers (TPCs) have been successfully used as the central tracking devices in a number of high-energy physics experiments. However, the performance requirements on TPCs for future high-energy physics experiments greatly exceed the abilities of traditional TPCs read out by multi-wire proportional chambers (MWPCs). Micro-pattern gas detectors (MPGDs), such as gas electron multipliers (GEMs) or micromegas, have great potential to improve TPC performance when used as readout detectors. In order to evaluate its feasibility, a GEM-based TPC prototype with a drift length up to 50 cm was designed. Measurements of the spatial resolution of cosmic-ray tracks without and with a magnetic field ( B =1 T) are presented. A very good performance is achieved, matching the analytic formula for the spatial resolution of a MPGD-readout TPC. A dedicated study shows that the increase of GEM detector gain can improve the TPC's spatial resolution.

title: An analytic solution of hydrodynamic equations with source terms in heavy-ion collisions
abstract: The energy and baryon densities in heavy-ion collisions are estimated by analytically solving a (1+1)-dimensional hydrodynamical model with source terms. In particular, a competition between the energy and baryon sources and the expansion of the system is discussed in detail.

title: Chiral Phase Transition Around the Tricritical Point

title: Simulation Study on neutrino nucleus cross section measurement in Segmented Detector at Spallation Neutron Source
abstract: Knowledge of νe-Fe/Pb differential cross sections for νe energy below several tens of MeV scale is believed to be crucial in understanding Supernova physics. In a segmented detector at Spallation Neutrino Source, νe energy reconstructed from the electron range measurement is strongly affected because of both multiple scattering and electromagnetic showers occurring along the electron passage in target materials. In order to estimate the effect, a simulation study has been performed with a cube block model assuming a perfect tracking precision. The distortion of energy spectrum is observed to be proportional to the atomic number of target material. Feasibility of unfolding the distorted νe energy spectrum is studied for both Fe and Pb cases. Evaluation of statistical accuracy attainable is therefore provided for a segmented detector.