47 research outputs found
Recent beam tests of CMS MSGC tracker prototypes
The performance of the MicroStrip Gas Chamber ( MSGC) prototypes, developed for the barrel Tracking Detector of the Compact Muon Solenoid ( CMS) experiment at LHC, has been extensively tested over the last years. We report the results from the most recent beam tests, illustrating the standard performance of the detectors and the robustness of the MSGC technology in LHC-like beam conditions
The NOMAD experiment at the CERN SPS
The NOMAD experiment is a short base-line search for oscillations in the CERN neutrino beam. The 's are searched for through their charged-current interactions followed by the observation of the resulting through its electronic, muonic or hadronic decays. These decays are recognized using kinematical criteria necessitating the use of a light target which enables the reconstruction of individual particles produced in the neutrino interactions. This paper describes the various components of the NOMAD detector: the target and muon drift chambers, the electromagnetic and hadronic calorimeters, the preshower and transition radiation detectors, and the veto and trigger scintillation counters. The beam and data acquisition system are also described. The quality of the reconstruction of individual particles is demonstrated through the ability of NOMAD to observe K's, 's and 's. Finally, the observation of through its electronic decay being one of the most promising channels in the search, the identification of electrons in NOMAD is discussed
The NOMAD Experiment at the CERN SPS
The NOMAD experiment is a short base-line search for Îœ<sub>ÎŒ</sub> â Îœ<sub>Ï</sub> oscillations in the CERN neutrino beam. The Îœ<sub>Ï</sub>'s are searched for through their charged current interactions followed by the observation of the resulting Ïâ through its electronic, muonic or hadronic decays. These decays are recognized using kinematical criteria necessitating the use of a light target which enables the reconstruction of individual particles produced in the neutrino interactions. This paper describes the various components of the NOMAD detector: the target and muon drift chambers, the electromagnetic and hadronic calorimeters, the preshower and transition radiation detectors and the veto and trigger scintillation counters. The beam and data acquisition system are also described. The quality of the reconstruction and individual particles is demonstrated through the ability of NOMAD to observe K<sub>s</sub><sup>0</sup>'s, Î<sup>0</sup>'s and Ï<sup>0</sup>'s. Finally, the observation of Ïâ through its electronic decay being one of the most promising channels in the search, the identification of electrons in NOMAD is discussed
Search for a new gauge boson in decays
A search was made for a new light gauge boson which might be produced in
decay from neutral pions generated by 450-GeV protons in
the CERN SPS neutrino target. The X's would penetrate the downstream shielding
and be observed in the NOMAD detector via the Primakoff effect, in the process
of conversion in the external Coulomb field of a nucleus. With
protons on target, 20 candidate events with energy between
8 and 140 GeV were found from the analysis of neutrino data.
This number is in agreement with the expectation of 18.12.8 background
events from standard neutrino processes. A new 90% C.L. upper limit on the
branching ratio for
masses ranging from 0 to 120 MeV/c^2 is obtained.Comment: 15 pages, LaTex, 6 eps figures included, submitted to Physics Letters
Recherche des interactions courant charge de dans l'experience Nomad
Reception of the images of a live catastrophe to television: Qualitative study of the reactions caused by the September 11, 2001 attempt in the United States through the recall of French viewers Abstract The present article explains the reactions of 56 French viewers to the in live images showing the attempt of New York and studies the reception process through the viewers recall, two months afterwards. The viewers are socially considered and their reactions are formulated in terms of information processing. The results are discussed in a theoretical framework built with social psychology theories of media messages reception and with several cognitive psychology models (e.g. flashbulb memory). During the first ten minutes of viewing, three different processes are characterized, on the one hand, by strong individual reactions where negative emotions and cognitive treatments of televisual information interact and, on the other hand, by strong needs for interpersonal communication, emotional exchanges and social co-construction of the event representation