117392007
Recent results from experiment NA52 at the CERN SPS
We present recent results of the NA52 experiment on the strangelet search and on particle, antiparticle, light nuclei and antinuclei production in minimum bias Pb + Pb collisions at 158 A GeV and zero production angle. Upper limits for the production of strangelets are given and one candidate found using less stringent lifetime cuts is discussed. The rapidity dependence of K+(K−), p(), d(), t and as well as first results on 4He, 6Li and 7Be at forward rapidities are presented. First results on the centrality dependence of the /p ratio are reported. Within the framework of a thermodynamical and a coalescence model, the temperature, the baryon- and strangeness-chemical potentials and the radius of the particle source at midrapidity have been estimated.
118548096
Measurement of the two-photon absorption cross-section of liquid argon with a time projection chamber
This paper reports on laser-induced multiphoton ionization at 266?nm of liquid argon in a time projection chamber (LAr TPC) detector. The electron signal produced by the laser beam is a formidable tool for the calibration and monitoring of next-generation large-mass LAr TPCs. The detector that we designed and tested allowed us to measure the two-photon absorption cross-section of LAr with unprecedented accuracy and precision: ?ex=(1.24?0.10stat?0.30syst)?10? 56?cm4?s? 1.
110306203
SVX4 User's manual
We present and describe the operation of the SVX4 chip. The SVX4 is a custom 128-channel analog to digital converter chip used by D0 and CDF in Run IIb to read out their respective silicon strip detectors. Each channel consists of an integrator (Front-End device, or FE) and a digitize/readout section (Back-End device, or BE). The input to each channel is sampled and temporarily stored in its own storage capacitor. Upon receiving a trigger signal, the relevant pipeline cell is reserved. Subsequent signals cause reserved cells to be digitized by a 128 parallel channel Wilkinson type 8-bit ADC, and then readout in byte-serial mode with optional zero suppression (sparsification). Salient features include (1) operation in either D0 mode or CDF mode (CDF mode features ''dead timeless operation'' or continued acquisition during digitization and readout) with an additional mixed mode of operation, (2) adjustable, loadable control parameters, including the integrator bandwidth and ADC polarity (only one input charge polarity will be used for Run IIb, but this feature remains for diagnostic purposes), (3) sparsified readout with nearest neighbor logic, (4) built-in charge injection with the ability for external voltage overriding for testing and calibration, and (5) a channel mask that ismore » used for either charge injection or for masking of channels with excessive DC current input during chip operation. This document is meant to familiarize the user with the functionality of the SVX4 and goes on to include specifications, pin outs, timings and electrical information. Additional information on the SVX4 can be found in Ref [1].« less
121921718
Hadronic response and e / pi separation with the H1 lead / fiber calorimeter
Hadronic response and electron identification performance of the new H1 lead-scintillating fibre calorimeter are investigated in the 1 to 7 GeV energy range using data taken at the CERN Proton Synchrotron. The energy response to minimum ionizing particles and interacting pions are studied and compared to Monte Carlo simulations. The measured energy of pions interacting either in the electromagnetic or in the hadronic section is found to scale linearly with the incident energy, providing an energy resolution σE ∼ 38% within a depth of one interaction length and σE ∼ 29% for a total depth of two interaction lengths. Several electron identification estimators are studied and combined as a function of energy and impact point. The probability for pions to be misidentified as electrons of any measured energy above 1 GeV ranges from 5% (for 2 GeV incident pions) to 0.4% (at 7 GeV) for an electron detection efficiency of 90%. The probability for pions of a given energy to be misidentified as electrons of the same energy falls to 0.25% at 7 GeV.
125650653
Study of hadronic event shapes with the CMS detector at LHC
125331327
The Fermilab anti-p accumulator ring for the charmonium experiment
119968279
A Study of Radon Background in the XENON100 Experiment
The XENON100 Dark Matter experiment has recently published first results from an analysis of 11.2 live days of data, setting an upper limit on the spin‐independent WIMP‐nucleon elastic scattering cross section of 3.4×10−44 cm2 at 55 GeV/c2 and 90% confidence level. This article focuses on one specific background component of the XENON100 detector by presenting two independent methods of measuring the 222Rn concentration during operation phase. A first estimate of radon activity is derived for the 11.2 days analysis, proving the feasibility of on‐line radon monitoring. Remaining systematic uncertainties are discussed.
108759303
R&D towards the module and service structure design for the ATLAS inner tracker at the super LHC (SLHC)
We have designed modules and a service structure of silicon microstrip detectors as a part of the ATLAS inner tracker for the SLHC project on the basis of a modular and replaceable concept. Six modules have been completed with common components and by similar procedures. Single module tests and four-module combined tests were performed at each site and have been compared for crosschecking. Details of the module design and electrical performance are presented. A half-module was irradiated up to 5 × 1014 1-MeV neq/cm2 using 24-GeV protons at the CERN PS. Its electrical performance was investigated before and after irradiation. The design of an eight-module structure, which is insertable to and is replaceable from the overall structure, has also been reported.