121869974
Fast simulation of showers in inhomogeneous media
Abstract A bootstrap method for fast shower simulation in inhomogeneous media has been developed. In sampling calorimeters the electromagnetic showers or hadronic showers of electrons, charged pions and neutrons, with energies below given thresholds, are replaced by pre-generated shower patterns. This method has been applied to the L3 hadron calorimeter. The speed of simulations of charged pion showers with energies between 1 to 10 GeV was increased by more than one order of magnitude, with most of the details of the hadron showers well reproduced as compared with full simulations.
120032974
Analysis and simulation of hadronic showers in a uranium gas-sampling calorimeter
Abstract The results of a simulation of the response of the L3 detector to hadrons is presented. The simulation is made on the basis of data obtained in the beam with the setup consisting of a uranium gas-sampling calorimeter with a bismuth germanium oxide calorimeter in front of it.
138378034
PERFORMANCES OF THE AMS-02 ELECTROMAGNETIC CALORIMETER
119474898
The topological branching fractions of $\tau$ decay at LEP
The paper has heen withdrawn.
123519682
PROSPECT OF PARTICLE PHYSICS IN CHINA
The nuclear physics and particle physics researches in China have a long tradition. BEPC is a milestone of the particle physics in China. The many interesting physics results were obtained from BEPC. Beijing Synchrotron Radiation Facility based on BEPC became the major synchrotron radiation facility in China. The upgrade of BEPC, which will increase the luminosity by two orders of magnitude, is going smoothly. The nonaccelerator based experiments were promoted also. Professor Yang made very important contribution to Chinese physics, especially to promote the large science facilities for the multiple discipline researches. The particle physics faces the great challenges, and meets the great opportunities in the 21st century. The medium-term plan of the particle physics in China was discussed.
9037500
Searches for supersymmetry using the MT2 variable in hadronic events produced in pp collisions at 8 TeV
A bstractSearches for supersymmetry (SUSY) are performed using a sample of hadronic events produced in 8 TeV pp collisions at the CERN LHC. The searches are based on the MT2 variable, which is a measure of the transverse momentum imbalance in an event. The data were collected with the CMS detector and correspond to an integrated luminosity of 19.5 fb−1. Two related searches are performed. The first is an inclusive search based on signal regions defined by the value of the MT2 variable, the hadronic energy in the event, the jet multiplicity, and the number of jets identified as originating from bottom quarks. The second is a search for a mass peak corresponding to a Higgs boson decaying to a bottom quark-antiquark pair, where the Higgs boson is produced as a decay product of a SUSY particle. For both searches, the principal backgrounds are evaluated with data control samples. No significant excess over the expected number of background events is observed, and exclusion limits on various SUSY models are derived.

118534772
Towards multi-field D-brane inflation in a warped throat
We study the inflationary dynamics in a model of slow-roll inflation in warped throat. Inflation is realized by the motion of a D-brane along the radial direction of the throat, and at later stages instabilities develop in the angular directions. We closely investigate both the single field potential relevant for the slow-roll phase, and the full multi-field one including the angular modes which becomes important at later stages. We study the main features of the instability process, discussing its possible consequences and identifying the vacua towards which the angular modes are driven.
7106931
The anatomy of gauge/string duality in Lunin-Maldacena background
We consider the correspondence between the spinning string solutions in Lunin-Maldacena background and the single trace operators in the Leigh-Strassler deformation of = 4 SYM. By imposing an appropriate rotating string ansatz on the Landau-Lifshitz reduced sigma model in the deformed SU(2) sector, we find two types of `elliptic' solutions with two spins, which turn out to be the solutions associated with the Neumann-Rosochatius system. We then calculate the string energies as functions of spins, and obtain their explicit forms in terms of a set of moduli parameters. On the deformed spin-chain side, we explicitly compute the one-loop anomalous dimensions of the gauge theory operators dual to each of the two types of spinning string solutions, extending and complementing the results of hep-th/0511164. Moreover, we propose explicit ansatz on how the locations of the Bethe strings are affected due to the deformation, with several supports from the string side.
10607038
Geometry and topology of bubble solutions from gauge theory
We study how geometrical and topological aspects of certain 1 -BPS type IIB supergravity solutions are captured by the N = 4 Super Yang-Mills gauge theory in the AdS/CFT context. The type IIB solutions are completely characterized by arbitrary droplets in a plane and we consider, in particular, concentric droplets. We probe the dual 1 -BPS operators of the gauge theory with single traces and extract their one-loop anomalous dimensions. The action of the one-loop dilatation operator can be reformulated as the Hamiltonian of a bosonic lattice. The operators defining the Hamiltonian encode the topology of the droplet. The axial symmetry of the droplets turns out to be essential for obtaining the spectrum of the Hamiltonians. In appropriate BMN limits, the near-BPS spectrum reproduces the spectrum of near-BPS string excitations propagating along each individual edge of the droplet of the dual geometric background. We also study semiclassical regimes for the Hamiltonians. We show that for droplets having disconnected constituents, the Hamiltonian admits different complimentary semiclassical descriptions, each one replicating the semiclassical description for closed strings extending in each of the constituents.
53378344
On integrable structure and geometric transition in supersymmetric gauge theories
A bstractWe generalize the exact field theoretic correspondence proposed in [1] and embed it into the context of refined topological string. The correspondence originally proposed from the common integrable structures in different field theories can be recast as a special limit of the refined geometric transition relating open and closed topological string partition functions. We realize the simplest examples of the correspondence explicitly in terms of open-closed geometric transition.
55556108
Extracting interstellar diffuse absorption bands from cool star spectra - Application to bulge clump giants in Baade’s window
Interstellar diffuse bands are usually extracted from hot star spectra because they are characterized by smooth continua. It introduces a strong limitation on the number of available targets, and reduces potential studies of the IS matter and the use of absorptions for cloud mapping. We have developed a new automatic fitting method appropriate to interstellar absorptions in spectra of cool stars that possess stellar atmospheric parameters. We applied this method to the extraction of three DIBs in high resolution VLT FLAMES/GIRAFFE spectra of red clump stars from the bulge. By combining all stellar synthetic spectra, HITRAN-LBLRTM atmospheric transmission spectra and diffuse band empirical absorption profiles, we determine the 6196, 6204, and 6284 A DIB strength toward the 219 target stars and discuss the sources of uncertainties. In order to test the sensitivity of the DIB extraction, we intercompare the three results and compare the DIB equivalent widths with the reddening derived from an independent extinction map based on OGLE photometric data. Most stellar spectra could be well reproduced by the composite stellar, atmospheric and interstellar models. Measurement uncertainties on the EWs are smaller for the broad and strong 6284 A DIB, and are of the order of 10-15%. Uncertainties on the two narrow and weaker DIBs are larger, as expected, and found to be highly variable from one target to the other. They strongly depend on the radial velocity of the star . DIB-DIB correlations among the three bands demonstrate that a meaningful signal is extracted. For the 6284 and 6204 A DIBs, the star-to-star variability of the equivalent width (EW) also reflects features of the OGLE extinction map...