5335139
Four-loop perturbative Konishi from strings and finite size effects for multiparticle states
We derive the perturbative four loop anomalous dimension of the Konishi operator in N = 4 SYM theory from the integrable string sigma model by evaluating the finite size effects using Luscher formulas adapted to multimagnon states at weak coupling. We obtain these multiparticle generalizations of Luscher formulas by studying certain exactly solvable relativistic integrable quantum field theories. The final result involves a summation of all bound states in the mirror theory and agrees with gauge theory perturbative computations.
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.
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.
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.
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.
120714913
Low-pressure drift chamber with a built-in scintillator
Abstract A low-pressure drift chamber with a built-in scintillator has been developed. Pulse height characteristics and the velocity of electrons, drifting in various electric fields in isobutane, have been measured. A standard deviation of the coordinate determined by measuring the drift time of the electrons has been found to be around 100 μm for a 20 mm drift length at 50 Torr of isobutane. A standard deviation of the second coordinate measured by a delay line is better than 100 μm. The work was performed at the High Energy Laboratory, JINR.
55827740
GEM-TPC TRACKERS FOR THE SUPER-FRS AT FAIR
For the slow extraction part of the beam diagnostics system of the Superconducting Projectile Fragment Separator (Super-FRS) of FAIR-facility a total of 32 detectors are needed. They will be used for beam monitoring, tracking and characterization of the produced ions. GEM-TPC detectors can perform over wide dynamic range without disturbing the beam and are thus suitable for this kind of in-beam detection. We present the simulations and first measurements with the GEMs of the Super-FRS GEM-TPC prototype.
18804192
The new element 111
The new element 111 was produced and unambiguously identified in an experiment at SHIP, GSI Darmstadt. Three nuclei of the isotope272111 were observed in irradiations of209Bi targets with64Ni projectiles of 318 MeV and 320 MeV energy. The cross-sections are (1.7−1.4+3.3) pb and (3.5−2.3+4.6) pb, respectively. The nuclei decay by a emission into the new and so far the heaviest isotopes of the elements 109 and 107 with mass numbers A=268 and A=264. Theα-decay chains were followed down to the known nuclei260105 and256Lr.
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.
122883967
Structure of neutron-rich oxygen isotopes
One-nucleon removal reactions at relativistic energies have been used as a spectroscopic tool for obtaining information about the ground state of neutron-rich oxygen isotopes. Using the FRS at GSI, the longitudinal momentum distributions of the emerging fragments after breakup were measured along with the one-nucleon removal cross-sections. The relative contributions of the remaining fragments in their ground and excited states have been determined for a few cases from measurements of γ rays in coincidence with the longitudinal momentum distribution. The controversial case of 23O has been directly addressed. Comparison of our exclusive momentum distributions for the one-neutron removal channel to theoretical momentum distributions calculated with an Eikonal model for the knockout process rendered a spin and parity of Iπ = 1/2+ for the 23O ground state. This result resolves the existent experimental discrepancy and supports sub-shell closure at N = 14 with a fairly pure 2s1/2 neutron in 23O.