15156007
Unified description of Bjorken and Landau 1+1 hydrodynamics
We propose a generalization of the Bjorken in-out Ansatz for fluid trajectories, which, when applied to the 1+1 hydrodynamic equations, generates a one-parameter family of analytic solutions interpolating between the boost-invariant Bjorken picture and the non-boost-invariant one by Landau. This parameter characterizes the proper-time scale when the fluid velocities approach the in-out Ansatz. We discuss the resulting rapidity distribution of entropy for various freeze-out conditions and compare it with the original Bjorken and Landau results.
7393750
Green's functions in non-hermitian random matrix models☆
Abstract We review some recent techniques for dealing with non-hermitian random matrix models based on generalized Green's functions. We introduce the diagrammatic methods in the hermitian case and generalize them to the non-hermitian case. The results are illustrated in terms of the eigenvalue distribution, eigenvector statistics and addition laws.
123645613
Chiral Disorder and the QCD Dirac Spectrum
Using the Cell-Mann-Oakes-Renner (COR) relation together with semi-classical argu­ ments, we show that the bulk quark spectrum in QCD exhibits a variety of regimes includ­ ing the ergodic one described by random matrix theory. We suggest that a class of chiral transitions in QCD is of the metal-insulator type, universal spectral statistics at the critical point.
118709171
Janus black holes
In this paper Janus black holes in A dS3 are considered. These are static solutions of an Einstein-scalar system with broken translation symmetry along the horizon. These solutions are dual to interface conformal field theories at finite temperature. An approximate solution is first constructed using perturbation theory around a planar BTZ blackhole. Numerical and exact solutions valid for all sets of parameters are then found and compared. Using the exact solution the thermodynamics of the system is analyzed. The entropy associated with the Janus black hole is calculated and it is found that the entropy of the black Janus is the sum of the undeformed black hole entropy and the entanglement entropy associated with the defect.
11654094
The decay of quantum D-branes
Abstract We study the quantum decay of D0-branes in two-dimensional 0B string theory. The quantum nature of the branes provides a natural cut-off for the closed string emission rate. We find exact quantum mechanical wave functions for the decaying branes and show how one can include the effects of the Fermi sea for any string coupling (Fermi energy).
119063881
New Results on the Odderon in QCD
We present our recent results on the odderon intercept in perturbative QCD, obtained through the solution of the Baxter equation and investigation of the spectrum of the relevant constant of motion.
123438213
Large size foil-microchannel plate timing detectors
Abstract A large area foil-microchannel plate time-of-flight (TOF) system is presented. The parameters of the system are as follows: 55 cm 2 active area, 99.8% detection efficiency, 100% transparency and 700 ps time resolution. The TOF system, unique in size and conditions of exploitation, consists of two (or three) detectors used also as anticoincidence units for the analysing multistrip Si-detector array.
123190188
TPC cathode read-out with C-pads
Abstract A Time Projection Chamber with “C” like shaped cathode pads was built and tested. It offers a low gas gain operation, a good pulse shape and a lightweight construction. The Pad Response Function (PRF), the cathode to anode pulse height ratios and the pad pulse shapes of the C-pad structure were measured and compared with planar cathode structures in two different wire geometries. The cathode to anode signal ratio was improved from between 0.2 and 0.4 up to 0.7. The PRF was considerably improved, it has a Gaussian shape and is narrower than in the case of the planar pads. The pulse shape from the C-pad read-out is similar to the pulse shape from a detector with a cylindrical shape of electrodes. A method for aluminum pad mass production based on a precise cold forging was developed and tested.
15755675
First measurement of beta decay half-lives in neutron-rich Tl and Bi isotopes
Neutron-rich isotopes around lead, beyond N=126, have been studied exploiting the fragmentation of an uranium primary beam at the FRS-RISING setup at GSI. For the first time β-decay half-lives of 219 Bi and 211,212,213 Tl isotopes have been derived. The half-lives have been extracted using a numerical simulation developed for experiments in high-background conditions. Comparison with state of the art models used in r-process calculations is given, showing a systematic underestimation of the experimental values, at variance from close-lying nuclei.
55910049
One-neutron removal reactions on Al isotopes around the N=20 shell closure
The one-neutron removal cross sections of neutron-rich Al isotopes and longitudinal momentum distributions of the residues have been measured for A=33 to 36 at relativistic energies (≈900 MeV/u). The inclusive data have been interpreted within the eikonal approximation. The evolution of the single-particle occupancy in the ground state of 33,34,35Al has been studied and compared with shell model predictions. The inferred 2s1/2 neutron occupancy in the 33Al ground-state wave function is 20% to 40% lower than the predicted one. The inclusive data do not exclude the presence of intruder states. Some intruder l=1 occupancy is found in 34Al, similarly to 33Mg. The single-particle 1f7/2 occupancy shows a gradual increase at N=22. Correspondingly, a decrease of the 1d3/2 strength has been observed.
19937921
Exploring the anomaly in the interaction cross section and matter radius of 23O
New measurements of the interaction cross sections of 22,23O at 900A MeV performed at the GSI, Darmstadt are reported that address the unsolved puzzle of the large cross section previously observed for 23O. The matter radii for these oxygen isotopes extracted through a Glauber model analysis are in good agreement with the new predictions of the ab initio coupled-cluster theory reported here. They are consistent with a 22O+neutron description of 23O as well.