In 2004, a combined system test was performed in the H8 beam line at the CERN SPS with a setup reproducing the geometry of sectors of the ATLAS Muon Spectrometer, formed by three stations of ...Monitored Drift Tubes (MDT). The full ATLAS analysis chain was used to obtain the results presented in this paper. The basic design performances of the Muon Spectrometer were verified. The stability of MDT calibration constants, the alignment system using optical devices and high energy tracks, as well as the intrinsic sagitta resolution of the Muon Spectrometer were studied and found to agree with expectations. The reconstruction of muon tracks using the combined information from both the Inner Detector and the Muon Spectrometer are also presented.
Delphi (DEtector with Lepton, Photon and Hadron Identification) is one of the four experiments of the LEP (Large Electron Positron) collider at CERN. The detector is laid out to provide a nearly ...4/spl pi/ coverage for charged particle tracking, electromagnetic, hadronic calorimetry and extended particle identification. The trigger system consists of four levels. The first two are synchronous with the BCO (beam cross over) and rely on hardwired control units, while the last two are performed asynchronously with respect to the BCO and are driven by the Delphi host computers. The aim of this paper is to give a comprehensive global view of the trigger system architecture, presenting in detail the first two levels, their various hardware components and the latest modifications introduced in order to improve their performance and make more user friendly the whole software user interface.< >
A measurement of the W boson mass and width has been performed by the DELPHI collaboration using the data collected during the full LEP2 programme (1996-2000). The data sample has an integrated ...luminosity of 660 pb^-1 and was collected over a range of centre-of-mass energies from 161 to 209 GeV. Results are obtained by applying the method of direct reconstruction of the mass of the W from its decay products in both the W+W- -> lvqq and W+W- -> qqqq channels. The W mass result for the combined data set is M_W = 80.336 +/- 0.055 (Stat.) +/- 0.028 (Syst.) +/- 0.025 (FSI) +/- 0.009 (LEP) GeV/c^2, where FSI represents the uncertainty due to final state interaction effects in the qqqq channel, and LEP represents that arising from the knowledge of the collision energy of the accelerator. The combined value for the W width is Gamma_W = 2.404 +/- 0.140 (Stat.) +/- 0.077 (Syst.) +/- 0.065 (FSI) GeV/c^2. These results supersede all values previously published by the DELPHI collaboration. This paper is dedicated to the memory of Carlo Caso.
In order to ensure that the resistive plate chambers used in the ATLAS experiment will not show, during their operation, any abnormal aging effect which could degrade their performances, an aging ...test is being performed at X5-GIF, CERN's gamma irradiation facility. In this paper, the latest results are presented, together with an example of successful damage recovery technique.
A girl with Thalassemia major reacted to a transfusion of packed red blood cells with increasing respiratory distress until death 12 1/2 hours later. Chills and fever were followed by dry cough, ...dyspnea, and pulmonary edema. The recipient had lymphocytotoxic antibodies specific for donor leukocyte antigens HL-A11 and possibly W14. At autopsy, the lungs showed pulmonary edema with extensive nonspecific acute alveolar injury. Similar cases in the literature are reviewed.
In the next years, the energy and intensity frontiers of the experimental Particle Physics will be pushed forward with the upgrade of existing accelerators (LHC at CERN) and the envisaged ...construction of new machines at energy scales up to hundreds TeV or with unprecedented intensity (FCC-hh, FCC-ee, ILC, Muon Collider). Large size, cost-effective, high-efficiency detection systems in high background environments are required in order to accomplish the physics program. MPGDs offer a diversity of technologies that allow them to meet the required performance challenges at future facilities thanks to the specific advantages that each technology provides. MPGDs allow stable operation, with environmentally friendly gas mixtures, at very high background particle flux with high detection efficiency and excellent spatial resolution. These features make MPGD one of the primary choices as precise muon tracking and trigger system in general-purpose detectors at future HEP colliders. In addition, the low material budget and the flexibility of the base material make MPGDs suitable for the development of very light, full cylindrical fine tracking inner trackers at lepton colliders. On-going R&Ds aim at pushing the detector performance at the limits of each technology. We are working in continuing to consolidate the construction and stable operation of large-size detectors, able to cope with large particle fluxes. In this white paper, we describe some of the most prominent MPGD technologies, their performance measurements, the challenges faced in the most recent applications, and the areas of improvement towards efficient tracking and Muon detection at future high energy physics colliders.
Purified α and β globin complementary DNAs (cDNAs) have been separated from total radioactively labeled human globin cDNA using mRNA purified from liver of a hydrops fetalis (α thalassemia). The β ...cDNA hybridizes to the hydrops fetalis mRNA while the α cDNA remains single-stranded. The purified α and β cDNAs were assayed for their purity by their hybridization to mRNA prepared from reticulocytes of nonthalassemia, α thalassemia, and β thalassemia subjects. The results indicate that the separated cDNAs are selective in hybridization to α or β globin mRNAs, respectively. The previously reported deficiency of globin mRNA in thalassemia cells has been confirmed with these purified cDNAs. The purified α and β cDNAs were hybridized to cellular DNA to determine the relative number of α - and β -like genes in non-thalassemia, β+thalassemia, and hydrops fetalis (α thalassemia) DNA. The α cDNA hybridized to hydrops fetalis liver DNA to a much lower extent than β cDNA, confirming the previously reported deletion of α globin genes in hydrops fetalis. By contrast, both the α and β cDNA probes hybridized to the same extent to spleen DNA from non-thalassemia and from β+thalassemia patients. Between two and five globin genes in non-thalassemia and β+thalassemia DNA hybridize to β cDNA and one to five to α cDNA. These studies indicate that in β+thalassemia, there is no detectable deletion in β globin genes. The genetic defect in β+thalassemia appears to be due to either repression of transcription of β globin genes or abnormal processing of β globin mRNA.
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