16294459
Anisotropic gravity solutions in AdS/CMT
We have constructed gravity solutions by breaking the Lorentzian symmetry to its subgroup, which means there is Galilean symmetry but without the rotational and boost invariance. This solution shows anisotropic behavior along both the temporal and spatial directions as well as among the spatial directions and more interestingly, it displays the precise scaling symmetry required for metric as well as the form fields. From the field theory point of view, it describes a theory which respects th5Ae scaling symmetry, $t\to \lambda^{z_1}t, x\to \lambda^{z_2}t, y\to \lambda y$, for $z_1\neq z_2$, as well as the translational symmetry associated to both time and space directions, which means we have found a non-rotational but Lifshitz-like fixed points from the dual field theory point of view. We also discuss the minimum number of generators required to see the appearance of such Lifshitz points. In 1+1 dimensional field theory, it is 3 and for 2+1 dimensional field theory, the number is 4.
985334
DERIVATIVE CORRECTIONS TO DIRAC–BORN–INFELD AND CHERN–SIMON ACTIONS FROM NONCOMMUTATIVITY
We show that the higher-order derivative α′ corrections to the Dirac–Born–Infeld (DBI) and Chern–Simon actions is derived from noncommutativity in the Seiberg–Witten limit, and is shown to agree with Wyllard's (hep-th/0008125) result, as conjectured by Das et al., (hep-th/0106024). In calculating the corrections, we have expressed in terms of F, Â in terms of A up to order , and made use of it.
8194131
Chiral symmetry breaking and restoration from holography
We study intersection of $N_c$ color D4 branes with $N_f$ Dp-branes and anti-Dp branes in the strong coupling limit in the probe approximation. The resulting model has $U(N_f)\times U(N_f)$ global symmetry. We see an $n$ dimensional theory for $n$ overlapping directions between color and flavor branes. At zero temperature we do see the breakdown of chiral symmetry, but there arises a puzzle: we do not see any massless NG boson to the break down of the chiral symmetry group for $n=2,3$ for a specific p. At finite temperature we do see the restoration of chiral symmetry group and the associated phase transitions are of first order. The chiral symmetry restoration is described by a curve, which connects L, the asymptotic distance of separation between the auarks, with the temperature, T. In general this quantity is very difficult to compute but if we evaluate it numerically then the curve is described by an equation $L T=c$, where c is a constant and is much smaller than one. It means for $L/R_{\tau}$ above $2\pi c$ there occurs the deconfined phase along with the chiral symmetryrestored phase.
118523867
RG FLOW OF TRANSPORT QUANTITIES
The RG flow equation of various transport quantities are studied in arbitrary space–time dimensions, in the fixed as well as fluctuating background geometry both for the Maxwellian and DBI type of actions. The regularity condition on the flow equation of the conductivity at the horizon for the DBI action reproduces naturally the leading order result of Hartnoll et al. [J. High Energy Phys. 04, 120 (2010)]. Motivated by the result of van der Marel et al. [Science 425, 271 (2003], we studied, analytically, the conductivity versus frequency plane by dividing it into three distinct parts: ω T and ω ≫ T. In order to compare, we choose (3+1)-dimensional bulk space–time for the computation of the conductivity. In the ω T range and staying away from the horizon, for the DBI action with unit dynamical exponent, nonzero magnetic field and charge density, the conductivity goes as ω-2/3, whereas the phase of the conductivity, goes as, arctan(Im σxx/Re σxx) = π/6 and arctan(Im σxy/Re σxy) = -π/3. There exists a universal quantity at the horizon that is the phase angle of conductivity, which either vanishes or an integral multiple of π. Furthermore, we calculate the temperature dependence to the thermoelectric and the thermal conductivity at the horizon. The charge diffusion constant for the DBI action is studied.
17626108
Branes in L(p,q,r)
Abstract We have found the solution to the back reaction of putting a stack of coincident D3- and D5-branes in R 3 , 1 × M 6 , where M 6 is constructed from an infinite class of Sasaki–Einstein spaces, L ( p , q , r ) . The non-zero fluxes associated to 2-form potential suggests the presence of a non-contractible 2-cycle in this geometry. The radial part of the warp factor has the usual form and possess the cascading feature. We argue that generically the duals of these SE spaces will have irrational central charges.
9583228
More gravity solutions of AdS/CMT
We have generalized the gravity solutions presented in arXiv:0808.1725 and arXiv:0808.3232 to arbitrary but even space time dimensions with the scaling symmetry $r \to \f{r}{\lambda}, x_i \to \lambda^b x_i, t \to \lambda^a t$. However, for $b=0$, we have the solution in arbitrary space time dimension, not restricted to even dimensional. The physical meaning of this particular choice of $b$ is that we can have a solution with only temporal scale invariance. From the dual field theory point of view, the BF bound and the unitarity bound for operators dual to scalar field is discussed.
122669506
High voltage characteristic of large area cathode pad chambers for muon spectrometer of ALICE
AbstractLarge area Cathode Pad Chambers (CPC) with inner and outer radii of 23.7 cm and 117 cm respectively have been fabricated and tested for 2nd Tracking station of Muon Spectrometer of ALICE.The active area of this detector has a radiation length of less than 2 % and the frames are fabricated with Peek GF-30. The anode wire plane consists of 474 anode wires of which 53 % have lengths greater than 1 meter. The separation between the wire plane and the grounded cathode plane is 2.5 mm. The high voltage behaviour of the chamber have been tested under two situations.
With no support below the wires to reduce sagging of long wires.With a G10 strip-support whose dimension is 950 mm × 2 mm × 2.4 mm.
 The High Voltage (HV) tests show that a better stability is achieved when the strip support is implemented. Therefore this solution has been adopted for operation in ALICE.
123325200
Production of antinuclei and hypernuclei in a relativistic Hagedorn resonance gas model
119271689
Event-plane correlators
Introduction.−High-energy heavy-ion collision experiments at the Relativistic Heavy-Ion Collider (RHIC), BNL and the Large Hadron Collider (LHC), CERN have firmly established the formation of strongly interacting matter which exhibits a strong collective flow [1–3]. This not only suggests that the matter formed is close to local thermal equilibrium but also provides a window to the initial state of the fireball immediately after the collision. Collective flow in the plane transverse to the beam axis is typically measured in terms of two-particle angular correlations [4–7] and its small anisotropies captured in its Fourier harmonics [8–11]. Recently, a new tool, namely correlations among event planes corresponding to different harmonics [12–14], is emerging with a promise to throw additional light on the initial-state phenomena. Pair correlations (i.e., the single-particle anisotropic flow vn extracted from two-particle correlations) are reasonably well understood [8]. Event-plane correlators represent higher-order correlations, involving at least three particles. Such higher-order correlations thus open a new direction in heavy-ion physics, much in the same way as studies of non-Gaussian fluctuations [15] in the early Universe. They bring in a large number of new observables which provide new, detailed insight into the hydrodynamic response and on the initial stage, and will significantly improve our understanding of heavy-ion collisions. The ATLAS collaboration [14] has recently released preliminary measurements of eight two-plane correlators (e.g., the correlation between the second and fourth harmonics) and six three-plane correlators (e.g., the mixed correlation between second, third and fifth harmonics) in Pb-Pb collisions at √ sNN = 2.76 TeV, as a function of the centrality of the collision. These correlators are qualitatively understood within event-by-event hydrodynamics [16] and provide new insight [17] into the interplay between the linear and nonlinear [18] hydrodynamic response [19, 20] to the initial density profile. The ATLAS analysis is very demanding in terms of detector acceptance: each event plane is determined in a separate pseudorapidity window; windows must be pairwise separated by gaps in order to suppress nonflow correlations; finally, each window must be wide enough to achieve a significant resolution in every Fourier harmonic up to order six. In this article, we show that the analysis can be done more simply, and that even three- and four-plane correlators can be safely analyzed with just two symmetric pseudorapidity windows, in the same way as two-plane correlators. The analysis can thus be performed by other experiments with smaller detector acceptance. We also explain in detail how to generalize the scalar-product method used earlier for two-particle flow analysis [21], to mixed correlations, so as to eliminate the ambiguity brought about by the event-plane method [22]. We carry out realistic simulations within a multiphase transport (AMPT) model [23]. Results are for the first time in quantitative agreement with the ATLAS measurements. In addition, we present predictions for several new correlators, in particular four-plane correlators. Method.−The azimuthal distribution of outgoing particles is decomposed in Fourier harmonics in each collision event. The flow vector in harmonic n is defined as [24],