Performance of CMS muon reconstruction in pp collision events at √s = 7TeV

Journal of Instrumentation 7:10 (2012)

Authors:

S Chatrchyan, V Khachatryan, AM Sirunyan, A Tumasyan, W Adam, T Bergauer, M Dragicevic, J Erö, C Fabjan, M Friedl, R Frühwirth, VM Ghete, J Hammer, M Hoch, N Hörmann, J Hrubec, M Jeitler, W Kiesenhofer, M Krammer, D Liko, I Mikulec, M Pernicka, B Rahbaran, C Rohringer, H Rohringer, R Schöfbeck, J Strauss, A Taurok, F Teischinger, P Wagner, W Waltenberger, G Walzel, E Widl, CE Wulz, V Mossolov, N Shumeiko, J Suarez Gonzalez, S Bansal, L Benucci, T Cornelis, EA De Wolf, X Janssen, S Luyckx, T Maes, L Mucibello, S Ochesanu, B Roland, R Rougny, M Selvaggi, H Van Haevermaet, P Van Mechelen, N Van Remortel, A Van Spilbeeck, F Blekman, S Blyweert, J D'Hondt, R Gonzalez Suarez, A Kalogeropoulos, M Maes, A Olbrechts, W Van Doninck, P Van Mulders, GP Van Onsem, I Villella, O Charaf, B Clerbaux, G De Lentdecker, V Dero, APR Gay, GH Hammad, T Hreus, A Léonard, PE Marage, L Thomas, C Vander Velde, P Vanlaer, J Wickens, V Adler, K Beernaert, A Cimmino, S Costantini, G Garcia, M Grunewald, B Klein, J Lellouch, A Marinov, J McCartin, AA Ocampo Rios, D Ryckbosch, N Strobbe, F Thyssen, M Tytgat, L Vanelderen, P Verwilligen, S Walsh, E Yazgan, N Zaganidis, S Basegmez, G Bruno, L Ceard

Abstract:

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40pb-1 of data collected in pp collisions at √s = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV/c is above 95% over the whole region of pseudorapidity covered by the CMS muon system, |η| < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV/c is higher than 90% over the full η range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100GeV/c and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV/c. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.

The LOFAR radio environment

(2012)

Authors:

AR Offringa, AG de Bruyn, S Zaroubi, G van Diepen, O Martinez-Ruby, P Labropoulos, MA Brentjens, B Ciardi, S Daiboo, G Harker, V Jelic, S Kazemi, LVE Koopmans, G Mellema, VN Pandey, RF Pizzo, J Schaye, H Vedantham, V Veligatla, SJ Wijnholds, S Yatawatta, P Zarka, A Alexov, J Anderson, A Asgekar, M Avruch, R Beck, M Bell, MR Bell, M Bentum, G Bernardi, P Best, L Birzan, A Bonafede, F Breitling, JW Broderick, M Bruggen, H Butcher, J Conway, M de Vos, RJ Dettmar, J Eisloeffel, H Falcke, R Fender, W Frieswijk, M Gerbers, JM Griessmeier, AW Gunst, TE Hassall, G Heald, J Hessels, M Hoeft, A Horneffer, A Karastergiou, V Kondratiev, Y Koopman, M Kuniyoshi, G Kuper, P Maat, G Mann, J McKean, H Meulman, M Mevius, JD Mol, R Nijboer, J Noordam, M Norden, H Paas, M Pandey, R Pizzo, A Polatidis, D Rafferty, S Rawlings, W Reich, HJA Rottgering, AP Schoenmakers, J Sluman, O Smirnov, C Sobey, B Stappers, M Steinmetz, J Swinbank, M Tagger, Y Tang, C Tasse, A van Ardenne, W van Cappellen, AP van Duin, M van Haarlem, J van Leeuwen, RJ van Weeren, R Vermeulen, C Vocks, RAMJ Wijers, M Wise, O Wucknitz

The Large Observatory for X-ray Timing (LOFT)

Experimental Astronomy 34:2 (2012) 415-444

Authors:

M Feroci, L Stella, M van der Klis, TJL Courvoisier, M Hernanz, R Hudec, A Santangelo, D Walton, A Zdziarski, D Barret, T Belloni, J Braga, S Brandt, C Budtz-Jørgensen, S Campana, JW den Herder, J Huovelin, GL Israel, M Pohl, P Ray, A Vacchi, S Zane, A Argan, P Attinà, G Bertuccio, E Bozzo, R Campana, D Chakrabarty, E Costa, A de Rosa, E Del Monte, S Di Cosimo, I Donnarumma, Y Evangelista, D Haas, P Jonker, S Korpela, C Labanti, P Malcovati, R Mignani, F Muleri, M Rapisarda, A Rashevsky, N Rea, A Rubini, C Tenzer, C Wilson-Hodge, B Winter, K Wood, G Zampa, N Zampa, MA Abramowicz, MA Alpar, D Altamirano, JM Alvarez, L Amati, C Amoros, LA Antonelli, R Artigue, P Azzarello, M Bachetti, G Baldazzi, M Barbera, C Barbieri, S Basa, A Baykal, R Belmont, L Boirin, V Bonvicini, L Burderi, M Bursa, C Cabanac, E Cackett, GA Caliandro, P Casella, S Chaty, J Chenevez, MJ Coe, A Collura, A Corongiu, S Covino, G Cusumano, F D'Amico, S Dall'Osso, D de Martino, G de Paris, G Di Persio, T Di Salvo, C Done, M Dovčiak, A Drago, U Ertan, S Fabiani, M Falanga, R Fender, P Ferrando, D della Monica Ferreira, G Fraser, F Frontera, F Fuschino

Abstract:

High-time-resolution X-ray observations of compact objects provide direct access to strong-field gravity, to the equation of state of ultradense matter and to black hole masses and spins. A 10 m 2-class instrument in combination with good spectral resolution is required to exploit the relevant diagnostics and answer two of the fundamental questions of the European Space Agency (ESA) Cosmic Vision Theme "Matter under extreme conditions", namely: does matter orbiting close to the event horizon follow the predictions of general relativity? What is the equation of state of matter in neutron stars? The Large Observatory For X-ray Timing (LOFT), selected by ESA as one of the four Cosmic Vision M3 candidate missions to undergo an assessment phase, will revolutionise the study of collapsed objects in our galaxy and of the brightest supermassive black holes in active galactic nuclei. Thanks to an innovative design and the development of large-area monolithic silicon drift detectors, the Large Area Detector (LAD) on board LOFT will achieve an effective area of ~12 m 2 (more than an order of magnitude larger than any spaceborne predecessor) in the 2-30 keV range (up to 50 keV in expanded mode), yet still fits a conventional platform and small/medium-class launcher. With this large area and a spectral resolution of <260 eV, LOFT will yield unprecedented information on strongly curved spacetimes and matter under extreme conditions of pressure and magnetic field strength. © 2011 Springer Science+Business Media B.V.

The progenitor mass of the Type IIP supernova SN 2004et from late-time spectral modeling⋆

Astronomy & Astrophysics EDP Sciences 546 (2012) a28

Authors:

A Jerkstrand, C Fransson, K Maguire, S Smartt, M Ergon, J Spyromilio

Search for pair production of first- and second-generation scalar leptoquarks in pp collisions at √s=7TeV

Physical Review D - Particles, Fields, Gravitation and Cosmology 86:5 (2012)

Authors:

S Chatrchyan, V Khachatryan, AM Sirunyan, A Tumasyan, W Adam, E Aguilo, T Bergauer, M Dragicevic, J Erö, C Fabjan, M Friedl, R Frühwirth, VM Ghete, J Hammer, N Hörmann, J Hrubec, M Jeitler, W Kiesenhofer, V Knünz, M Krammer, I Krätschmer, D Liko, I Mikulec, M Pernicka, B Rahbaran, C Rohringer, H Rohringer, R Schöfbeck, J Strauss, A Taurok, W Waltenberger, G Walzel, E Widl, CE Wulz, V Mossolov, N Shumeiko, J Suarez Gonzalez, M Bansal, S Bansal, T Cornelis, EA De Wolf, X Janssen, S Luyckx, L Mucibello, S Ochesanu, B Roland, R Rougny, M Selvaggi, Z Staykova, H Van Haevermaet, P Van Mechelen, N Van Remortel, A Van Spilbeeck, F Blekman, S Blyweert, J D'Hondt, R Gonzalez Suarez, A Kalogeropoulos, M Maes, A Olbrechts, W Van Doninck, P Van Mulders, GP Van Onsem, I Villella, B Clerbaux, G De Lentdecker, V Dero, APR Gay, T Hreus, A Léonard, PE Marage, T Reis, L Thomas, G Vander Marcken, C Vander Velde, P Vanlaer, J Wang, V Adler, K Beernaert, A Cimmino, S Costantini, G Garcia, M Grunewald, B Klein, J Lellouch, A Marinov, J McCartin, AA Ocampo Rios, D Ryckbosch, N Strobbe, F Thyssen, M Tytgat, P Verwilligen, S Walsh, E Yazgan, N Zaganidis, S Basegmez, G Bruno, R Castello, L Ceard

Abstract:

Results are presented from a search for the pair production of first- and second-generation scalar leptoquarks in proton-proton collisions at √s=7TeV. The data sample corresponds to an integrated luminosity of 5.0fb-1, collected by the CMS detector at the LHC. The search signatures involve either two charged leptons of the same flavor (electrons or muons) and at least two jets or a single charged lepton (electron or muon), missing transverse energy, and at least two jets. If the branching fraction of the leptoquark decay into a charged lepton and a quark is assumed to be β=1, leptoquark pair production is excluded at the 95% confidence level for masses below 830 GeV and 840 GeV for the first and second generations, respectively. For β=0.5, masses below 640 GeV and 650 GeV are excluded. These limits are the most stringent to date. © 2012 CERN.