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Measurement of b-jet shapes in inclusive jet production in pp̄ collisions at s=1.96TeV

Physical Review D - Particles, Fields, Gravitation and Cosmology 78:7 (2008)

Authors:

T Aaltonen, J Adelman, T Akimoto, MG Albrow, BA González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, A Apresyan, T Arisawa, A Artikov, W Ashmanskas, A Attal, A Aurisano, F Azfar, P Azzurri, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, V Bartsch, G Bauer, PH Beauchemin, F Bedeschi, P Bednar, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, J Beringer, A Bhatti, M Binkley, D Bisello, I Bizjak, RE Blair, C Blocker, B Blumenfeld, A Bocci, A Bodek, V Boisvert, G Bolla, D Bortoletto, J Boudreau, A Boveia, B Brau, A Bridgeman, L Brigliadori, C Bromberg, E Brubaker, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, KL Byrum, S Cabrera, C Calancha, M Campanelli, M Campbell, F Canelli, A Canepa, 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, SH Chang, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, G Choudalakis, SH Chuang, K Chung, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, A Clark, D Clark, G Compostella

Abstract:

We present a measurement of the shapes of b-jets using 300pb-1 of data obtained with the upgraded Collider Detector at Fermilab (CDF II) in pp̄ collisions at center-of-mass energy s=1.96TeV. This measurement covers a wide transverse momentum range, from 52 to 300GeV/c. Samples of heavy-flavor enhanced jets together with inclusive jets are used to extract the average shapes of b-jets. The b-jets are expected to be broader than inclusive jets. Moreover, b-jets containing a single b-quark are expected to be narrower than those containing a bb̄ pair from gluon splitting. The measured b-jet shapes are found to be significantly broader than expected from the pythia and herwig Monte Carlo simulations. This effect may arise from an underestimation of the fraction of b-jets originating from gluon splitting in these simulations. The jet shape distributions provided in this paper could be compared to any full Monte Carlo simulation and could be used to further constrain the various parameters. © 2008 The American Physical Society.
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Testing Lorentz invariance and CPT conservation with NuMI neutrinos in the MINOS near detector.

Phys Rev Lett 101:15 (2008) 151601

Authors:

P Adamson, C Andreopoulos, KE Arms, R Armstrong, DJ Auty, DS Ayres, B Baller, G Barr, WL Barrett, BR Becker, A Belias, RH Bernstein, D Bhattacharya, M Bishai, A Blake, GJ Bock, J Boehm, DJ Boehnlein, D Bogert, C Bower, E Buckley-Geer, S Cavanaugh, JD Chapman, D Cherdack, S Childress, BC Choudhary, SJ Coleman, AJ Culling, JK de Jong, MV Diwan, M Dorman, SA Dytman, CO Escobar, JJ Evans, E Falk Harris, GJ Feldman, MV Frohne, HR Gallagher, MC Goodman, P Gouffon, R Gran, EW Grashorn, N Grossman, K Grzelak, A Habig, D Harris, PG Harris, J Hartnell, R Hatcher, K Heller, A Himmel, A Holin, J Hylen, GM Irwin, M Ishitsuka, DE Jaffe, C James, D Jensen, T Kafka, SMS Kasahara, JJ Kim, G Koizumi, S Kopp, M Kordosky, DJ Koskinen, A Kreymer, S Kumaratunga, K Lang, J Ling, PJ Litchfield, RP Litchfield, L Loiacono, P Lucas, J Ma, WA Mann, ML Marshak, JS Marshall, N Mayer, AM McGowan, JR Meier, MD Messier, CJ Metelko, DG Michael, JL Miller, WH Miller, SR Mishra, CD Moore, J Morfín, L Mualem, S Mufson, S Murgia, J Musser, D Naples, JK Nelson, HB Newman, RJ Nichol, TC Nicholls, JP Ochoa-Ricoux, WP Oliver, R Ospanov, J Paley, V Paolone, A Para, T Patzak, Z Pavlović, G Pawloski, GF Pearce, CW Peck, DA Petyt, R Pittam, RK Plunkett, A Rahaman, RA Rameika, TM Raufer, B Rebel, J Reichenbacher, PA Rodrigues, C Rosenfeld, HA Rubin, MC Sanchez, N Saoulidou, J Schneps, P Schreiner, P Shanahan, W Smart, A Sousa, B Speakman, P Stamoulis, M Strait, N Tagg, RL Talaga, MA Tavera, J Thomas, J Thompson, MA Thomson, JL Thron, G Tinti, G Tzanakos, J Urheim, P Vahle, B Viren, M Watabe, A Weber, RC Webb, A Wehmann, N West, C White, SG Wojcicki, T Yang, M Zois, K Zhang, R Zwaska, MINOS Collaboration

Abstract:

A search for a sidereal modulation in the MINOS near detector neutrino data was performed. If present, this signature could be a consequence of Lorentz and CPT violation as predicted by the effective field theory called the standard-model extension. No evidence for a sidereal signal in the data set was found, implying that there is no significant change in neutrino propagation that depends on the direction of the neutrino beam in a sun-centered inertial frame. Upper limits on the magnitudes of the Lorentz and CPT violating terms in the standard-model extension lie between 10(-4) and 10(-2) of the maximum expected, assuming a suppression of these signatures by a factor of 10(-17).
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Search for t over(t, ̄) resonances in the lepton plus jets final state in p over(p, ̄) collisions at sqrt(s) = 1.96 TeV

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 668:2 (2008) 98-104

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, E Aguilo, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, LS Ancu, T Andeen, S Anderson, B Andrieu, MS Anzelc, M Aoki, Y Arnoud, M Arov, M Arthaud, A Askew, B Åsman, ACSA Jesus, O Atramentov, C Avila, F Badaud, A Baden, L Bagby, B Baldin, DV Bandurin, P Banerjee, S Banerjee, E Barberis, AF Barfuss, P Bargassa, P Baringer, J Barreto, JF Bartlett, U Bassler, D Bauer, S Beale, A Bean, M Begalli, M Begel, C Belanger-Champagne, L Bellantoni, A Bellavance, JA Benitez, SB Beri, G Bernardi, R Bernhard, I Bertram, M Besançon, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, C Biscarat, G Blazey, F Blekman, S Blessing, D Bloch, K Bloom, A Boehnlein, D Boline, TA Bolton, EE Boos, G Borissov, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, D Brown, NJ Buchanan, D Buchholz, M Buehler, V Buescher, V Bunichev, S Burdin, S Burke, TH Burnett, CP Buszello, JM Butler, P Calfayan, S Calvet, J Cammin, W Carvalho, BCK Casey, H Castilla-Valdez, S Chakrabarti, D Chakraborty, K Chan, KM Chan, A Chandra, F Charles

Abstract:

We present a search for a narrow-width heavy resonance decaying into top quark pairs (X → t over(t, ̄)) in p over(p, ̄) collisions at sqrt(s) = 1.96 TeV using approximately 0.9 fb-1 of data collected with the DØ detector at the Fermilab Tevatron Collider. This analysis considers t over(t, ̄) candidate events in the lepton plus jets channel with at least one identified b jet and uses the t over(t, ̄) invariant mass distribution to search for evidence of resonant production. We find no evidence for a narrow resonance X decaying to t over(t, ̄). Therefore, we set upper limits on σX ṡ B (X → t over(t, ̄)) for different hypothesized resonance masses using a Bayesian approach. For a Topcolor-assisted technicolor model, the existence of a leptophobic Z′ boson with mass MZ′ < 700 GeV and width ΓZ′ = 0.012 MZ′ can be excluded at the 95% C.L. © 2008 Elsevier B.V.
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Measurement of the inclusive jet cross section at the Fermilab Tevatron pp̄ collider using a cone-based jet algorithm

Physical Review D - Particles, Fields, Gravitation and Cosmology 78:5 (2008)

Authors:

T Aaltonen, J Adelman, T Akimoto, MG Albrow, B Álvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, A Apresyan, T Arisawa, A Artikov, W Ashmanskas, A Attal, A Aurisano, F Azfar, P Azzurri, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, V Bartsch, G Bauer, PH Beauchemin, F Bedeschi, P Bednar, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, J Beringer, A Bhatti, M Binkley, D Bisello, I Bizjak, RE Blair, C Blocker, B Blumenfeld, A Bocci, A Bodek, V Boisvert, G Bolla, D Bortoletto, J Boudreau, A Boveia, B Brau, A Bridgeman, L Brigliadori, C Bromberg, E Brubaker, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, KL Byrum, S Cabrera, C Calancha, M Campanelli, M Campbell, F Canelli, A Canepa, 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, SH Chang, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, G Choudalakis, SH Chuang, K Chung, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, A Clark, D Clark, G Compostella

Abstract:

We present a measurement of the inclusive jet cross section in pp̄ collisions at s=1.96TeV based on data collected by the CDF II detector with an integrated luminosity of 1.13fb-1. The measurement was made using the cone-based midpoint jet clustering algorithm in the rapidity region of |y|<2.1. The results are consistent with next-to-leading-order perturbative QCD predictions based on recent parton distribution functions (PDFs), and are expected to provide increased precision in PDFs at high parton momentum fraction x. The results are also compared to the recent inclusive jet cross section measurement using the kT jet clustering algorithm, and we find that the ratio of the cross sections measured with the two algorithms is in agreement with theoretical expectations over a large range of jet transverse momentum and rapidity. © 2008 The American Physical Society.
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Measurement of neutrino oscillations with the MINOS detectors in the NuMI beam.

Phys Rev Lett 101:13 (2008) 131802

Authors:

P Adamson, C Andreopoulos, KE Arms, R Armstrong, DJ Auty, DS Ayres, B Baller, PD Barnes, G Barr, WL Barrett, BR Becker, A Belias, RH Bernstein, D Bhattacharya, M Bishai, A Blake, GJ Bock, J Boehm, DJ Boehnlein, D Bogert, C Bower, E Buckley-Geer, S Cavanaugh, JD Chapman, D Cherdack, S Childress, BC Choudhary, JH Cobb, SJ Coleman, AJ Culling, JK de Jong, M Dierckxsens, MV Diwan, M Dorman, SA Dytman, CO Escobar, JJ Evans, E Falk Harris, GJ Feldman, MV Frohne, HR Gallagher, A Godley, MC Goodman, P Gouffon, R Gran, EW Grashorn, N Grossman, K Grzelak, A Habig, D Harris, PG Harris, J Hartnell, R Hatcher, K Heller, A Himmel, A Holin, J Hylen, GM Irwin, M Ishitsuka, DE Jaffe, C James, D Jensen, T Kafka, SMS Kasahara, JJ Kim, MS Kim, G Koizumi, S Kopp, M Kordosky, DJ Koskinen, SK Kotelnikov, A Kreymer, S Kumaratunga, K Lang, J Ling, PJ Litchfield, RP Litchfield, L Loiacono, P Lucas, J Ma, WA Mann, A Marchionni, ML Marshak, JS Marshall, N Mayer, AM McGowan, JR Meier, GI Merzon, MD Messier, CJ Metelko, DG Michael, JL Miller, WH Miller, SR Mishra, CD Moore, J Morfín, L Mualem, S Mufson, S Murgia, J Musser, D Naples, JK Nelson, HB Newman, RJ Nichol, TC Nicholls, JP Ochoa-Ricoux, WP Oliver, R Ospanov, J Paley, V Paolone, A Para, T Patzak, Z Pavlović, G Pawloski, GF Pearce, CW Peck, EA Peterson, DA Petyt, R Pittam, RK Plunkett, A Rahaman, RA Rameika, TM Raufer, B Rebel, J Reichenbacher, PA Rodrigues, C Rosenfeld, HA Rubin, K Ruddick, VA Ryabov, MC Sanchez, N Saoulidou, J Schneps, P Schreiner, S-M Seun, P Shanahan, W Smart, C Smith, A Sousa, B Speakman, P Stamoulis, M Strait, P Symes, N Tagg, RL Talaga, MA Tavera, J Thomas, J Thompson, MA Thomson, JL Thron, G Tinti, I Trostin, VA Tsarev, G Tzanakos, J Urheim, P Vahle, B Viren, CP Ward, DR Ward, M Watabe, A Weber, RC Webb, A Wehmann, N West, C White, SG Wojcicki, DM Wright, T Yang, M Zois, K Zhang, R Zwaska, MINOS Collaboration

Abstract:

This Letter reports new results from the MINOS experiment based on a two-year exposure to muon neutrinos from the Fermilab NuMI beam. Our data are consistent with quantum-mechanical oscillations of neutrino flavor with mass splitting |Deltam2| = (2.43+/-0.13) x 10(-3) eV2 (68% C.L.) and mixing angle sin2(2theta) > 0.90 (90% C.L.). Our data disfavor two alternative explanations for the disappearance of neutrinos in flight: namely, neutrino decays into lighter particles and quantum decoherence of neutrinos, at the 3.7 and 5.7 standard-deviation levels, respectively.
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