ATLAS

Research group

Research theme

Sub department

About

Related research groups

Search for excited leptons in proton-proton collisions at √s=7TeV with the ATLAS detector

Physical Review D - Particles, Fields, Gravitation and Cosmology 85:7 (2012)

Authors:

G Aad, B Abbott, J Abdallah, AA Abdelalim, A Abdesselam, O Abdinov, B Abi, M Abolins, OS Abouzeid, H Abramowicz, H Abreu, E Acerbi, BS Acharya, L Adamczyk, DL Adams, TN Addy, J Adelman, M Aderholz, S Adomeit, P Adragna, T Adye, S Aefsky, JA Aguilar-Saavedra, M Aharrouche, SP Ahlen, F Ahles, A Ahmad, M Ahsan, G Aielli, T Akdogan, TPA Akesson, G Akimoto, AV Akimov, A Akiyama, MS Alam, MA Alam, J Albert, S Albrand, M Aleksa, IN Aleksandrov, F Alessandria, C Alexa, G Alexander, G Alexandre, T Alexopoulos, M Alhroob, M Aliev, G Alimonti, J Alison, M Aliyev, BMM Allbrooke, PP Allport, SE Allwood-Spiers, J Almond, A Aloisio, R Alon, A Alonso, B Alvarez Gonzalez, MG Alviggi, K Amako, P Amaral, C Amelung, VV Ammosov, A Amorim, G Amorós, N Amram, C Anastopoulos, LS Ancu, N Andari, T Andeen, CF Anders, G Anders, KJ Anderson, A Andreazza, V Andrei, ML Andrieux, XS Anduaga, A Angerami, F Anghinolfi, A Anisenkov, N Anjos, A Annovi, A Antonaki, M Antonelli, A Antonov, J Antos, F Anulli, S Aoun, L Aperio Bella, R Apolle, G Arabidze, I Aracena, Y Arai, ATH Arce, S Arfaoui, JF Arguin, E Arik, M Arik, AJ Armbruster, O Arnaez

Abstract:

The ATLAS detector is used to search for excited leptons in the electromagnetic radiative decay channel *→γ. Results are presented based on the analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding to an integrated luminosity of 2.05fb-1. No evidence for excited leptons is found, and limits are set on the compositeness scale Λ as a function of the excited lepton mass m *. In the special case where Λ=m *, excited electron and muon masses below 1.87 TeV and 1.75 TeV are excluded at 95% C.L., respectively. © 2012 CERN.
More details from the publisher
More details

Observation of a new Xi(b) baryon

ArXiv 1204.5955 (2012)
Details from ArXiV

The radiation tolerance of MTP and LC optical fibre connectors to 500 kGy(Si) of gamma radiation

JINST IOP 7:4 (2012) P04014

Authors:

D Hall, P Hamilton, BT Huffman, PK Teng, AR Weidberg

Abstract:

The LHC luminosity upgrade, known as the High Luminosity LHC (HL-LHC), will require high-speed optical links to read out data from the detectors. The optical fibre connectors contained within such a link must have a small form factor and be capable of operating in the harsh radiation environment at the HL-LHC. MTP ribbon fibre connectors and LC single fibre connectors were exposed to 500 kGy(Si) of gamma radiation and their radiation hardness was investigated. Neither type of connector exhibited evidence for any significant radiation damage and both connectors could be qualified for use at HL-LHC detectors.
More details from the publisher
More details

Search for supersymmetry in events with three leptons and missing transverse momentum in sqrt(s) = 7 TeV pp collisions with the ATLAS detector

ArXiv 1204.5638 (2012)
Details from ArXiV

Measurement of the CP-violating phase βsJ/ψ in Bs0→J/ψ decays with the CDF II detector

Physical Review D - Particles, Fields, Gravitation and Cosmology 85:7 (2012)

Authors:

T Aaltonen, B Alvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, T Bae, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, F Bedeschi, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, D Bisello, I Bizjak, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, N Bousson, A Boveia, L Brigliadori, C Bromberg, E Brucken, J Budagov, HS Budd, K Burkett, G Busetto, P Bussey, A Buzatu, A Calamba, C Calancha, S Camarda, M Campanelli, M Campbell, F Canelli, B Carls, D Carlsmith, R Carosi, S Carrillo, S Carron, B Casal, M Casarsa, A Castro, P Catastini, D Cauz, V Cavaliere, M Cavalli-Sforza, A Cerri, L Cerrito, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, WH Chung, YS Chung, MA Ciocci, A Clark, C Clarke, G Compostella, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Crescioli, J Cuevas, R Culbertson, D Dagenhart, N D'ascenzo, M Datta, P De Barbaro, M Dell'orso, L Demortier, M Deninno, F Devoto

Abstract:

We present a measurement of the CP-violating parameter βsJ/ψ using approximately 6500 Bs0→J/ψ decays reconstructed with the CDF II detector in a sample of pp̄ collisions at √s=1.96TeV corresponding to 5.2fb -1 integrated luminosity produced by the Tevatron collider at Fermilab. We find the CP-violating phase to be within the range βsJ/ψ [0.02,0.52] [1.08,1.55] at 68% confidence level where the coverage property of the quoted interval is guaranteed using a frequentist statistical analysis. This result is in agreement with the standard model expectation at the level of about one Gaussian standard deviation. We consider the inclusion of a potential S-wave contribution to the Bs0→J/ψK +K - final state which is found to be negligible over the mass interval 1.009
More details from the publisher
Details from ArXiV