ATLAS

Research group

Research theme

Sub department

About

Related research groups

Two-particle momentum correlations in jets produced in pp̄ collisions at s=1.96TeV

Physical Review D - Particles, Fields, Gravitation and Cosmology 77:9 (2008)

Authors:

T Aaltonen, J Adelman, T Akimoto, MG Albrow, BA González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, M Aoki, G Apollinari, A Apresyan, T Arisawa, A Artikov, W Ashmanskas, A Attal, A Aurisano, F Azfar, P Azzi-Bacchetta, P Azzurri, N Bacchetta, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, S Baroiant, V Bartsch, G Bauer, PH Beauchemin, F Bedeschi, P Bednar, S Behari, G Bellettini, J Bellinger, A Belloni, D Benjamin, A Beretvas, J Beringer, T Berry, A Bhatti, M Binkley, D Bisello, I Bizjak, RE Blair, C Blocker, B Blumenfeld, A Bocci, A Bodek, V Boisvert, G Bolla, A Bolshov, 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, 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, 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

Abstract:

We present the first measurement of two-particle momentum correlations in jets produced in pp̄ collisions at s=1.96TeV. Results are obtained for charged particles within a restricted cone with an opening angle of 0.5 radians around the jet axis and for events with dijet masses between 66 and 563GeV/c2. A comparison of the experimental data to theoretical predictions obtained for partons within the framework of resummed perturbative QCD in the next-to-leading log approximation shows that the parton momentum correlations survive the hadronization stage of jet fragmentation, giving further support to the hypothesis of local parton-hadron duality. The extracted value of the next-to-leading-log-approximation parton shower cutoff scale Qeff set equal to ΛQCD is found to be (1.4-0.7+0.9)×100MeV. © 2008 The American Physical Society.
More details from the publisher

A combined search for the standard model Higgs boson at sqrt(s) = 1.96   TeV

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 663:1-2 (2008) 26-36

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, Y Arnoud, M Arov, M Arthaud, A Askew, B Åsman, ACSA Jesus, O Atramentov, C Autermann, C Avila, C Ay, F Badaud, A Baden, L Bagby, B Baldin, S Banerjee, P 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, 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, NM Cason, H Castilla-Valdez, S Chakrabarti, D Chakraborty, KM Chan, K Chan, A Chandra, F Charles

Abstract:

We present new results of the search for W H → ℓ ν b over(b, ̄) production in p over(p, ̄) collisions at a center-of-mass energy of sqrt(s) = 1.96   TeV, based on a dataset with integrated luminosity of 0.44   fb-1. We combine these new results with previously published searches by the D0 collaboration, for WH and ZH production analyzed in the E{combining long solidus overlay}T b over(b, ̄) final state, for ZH (→ ℓ+ ℓ- b over(b, ̄)) production, for WH (→ W W W) production, and for H (→ W W) direct production. No signal-like excess is observed either in the WH analysis or in the combination of all D0 Higgs boson analyses. We set 95% C.L. (expected) upper limits on σ (p over(p, ̄) → W H) × B (H → b over(b, ̄)) ranging from 1.6 (2.2) pb to 1.9 (3.3) pb for Higgs boson masses between 105 and 145 GeV, to be compared to the theoretical prediction of 0.13 pb for a Standard Model (SM) Higgs boson with mass mH = 115   GeV. After combination with the other D0 Higgs boson searches, we obtain for mH = 115   GeV an observed (expected) limit 8.5 (12.1) times higher than the SM predicted Higgs boson production cross section. For mH = 160   GeV, the corresponding observed (expected) ratio is 10.2 (9.0). © 2008 Elsevier B.V.
More details from the publisher
More details

Measurement of the tt̄ production cross section in pp̄ collisions at s=1.96TeV

Physical Review Letters 100:19 (2008)

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 Asman, ACS Assis Jesus, O Atramentov, C Avila, C Ay, 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, 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 measure the tt̄ production cross section in pp̄ collisions at s=1.96TeV in the lepton+jets channel. Two complementary methods discriminate between signal and background: b tagging and a kinematic likelihood discriminant. Based on 0.9fb-1 of data collected by the D0 detector at the Fermilab Tevatron Collider, we measure σtt̄=7.62±0.85pb, assuming the current world average mt=172.6GeV. We compare our cross section measurement with theory predictions to determine a value for the top-quark mass of 170±7GeV. © 2008 The American Physical Society.
More details from the publisher
More details
Details from ArXiV

Search for the Flavor Changing Neutral Current Decay t $\to Zq$ in $p \bar{p}$ Collisions at $\sqrt{s}=1.96$

ArXiv 0805.2109 (2008)

Authors:

CDF Collaboration, T Aaltonen
Details from ArXiV

Simultaneous Measurement of the Ratio R=B(t→Wb)/B(t→Wq) and the Top-Quark Pair Production Cross Section with the D0 Detector at s=1.96TeV

Physical Review Letters 100:19 (2008)

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, Y Arnoud, M Arov, M Arthaud, A Askew, B Ásman, ACS Assis Jesus, O Atramentov, C Autermann, C Avila, C Ay, F Badaud, A Baden, L Bagby, B Baldin, DV Bandurin, S Banerjee, P 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, 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, NM Cason, H Castilla-Valdez, S Chakrabarti, D Chakraborty, KM Chan, K Chan, A Chandra

Abstract:

We present the first simultaneous measurement of the ratio of branching fractions, R=B(t→Wb)/B(t→Wq), with q being a d, s, or b quark, and the top-quark pair production cross section σtt̄ in the lepton plus jets channel using 0.9fb-1 of pp̄ collision data at s=1.96TeV collected with the D0 detector. We extract R and σtt̄ by analyzing samples of events with 0, 1, and 2 identified b jets. We measure R=0.97-0.08+0.09(stat+syst) and σtt̄=8.18-0.84+0.90(stat+syst)±0.50(lumi)pb, in agreement with the standard model prediction. © 2008 The American Physical Society.
More details from the publisher
More details