Measurement of the inclusive jet cross section in pp collisions at \/s = 1.8 TeV

Physical Review D 64:3 (2001)

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, SR Amendolia, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, F Azfar, P Azzi-Bacchetta, N Bacchetta, MW Bailey, S Bailey, P de Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, S Baroiant, M Barone, G Bauer, F Bedeschi, S Belforte, WH Bell, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, B Bevensee, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, S van den Brink, C Bromberg, M Brozovic, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, P Calafiura, M Campbell, W Carithers, J Carlson, D Carlsmith, W Caskey, J Cassada, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, MT Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, YS Chung, CI Ciobanu, AG Clark, A Connolly, J Conway, M Cordelli, J Cranshaw, D Cronin-Hennessy, R Cropp, R Culbertson, D Dagenhart, S D’Auria

Abstract:

We present results from the measurement of the inclusive jet cross section for jet transverse energies from 40 to 465 GeV in the pseudorapidity range 0.1< | ?7|< 0.7. The results are based on 87 pb~' of data collected by the CDF Collaboration at the Fermilab Tevatron collider. The data are consistent with previously published results. The data are also consistent with QCD predictions given the flexibility allowed from current knowledge of the proton parton distributions. We develop a new procedure for ranking the agreement of the parton distributions with data and find that the data are best described by QCD predictions using the parton distribution functions which have a large gluon contribution at high ET (CTEQ4HJ).

Observation of orbitally excited B mesons in pp̄ collisions at √s=1.8 TeV

Physical Review D 64:7 (2001)

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, SR Amendolia, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, MW Bailey, S Bailey, P De Barbara, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, G Bauer, F Bedeschi, S Belferte, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, S Bertolucci, B Bevensee, A Bhatti, C Bigongiari, M Binkley, D Bisello, RE Blair, C Blocker, K Bloom, B Blumenfeld, BS Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandi, S Van Den Brink, C Bromberg, M Brozovic, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, M Campbell, A Caner, W Carithers, J Carlson, D Carlsmith, J Cassada, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, MT Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, S Cihangir, CI Ciobanu, AG Clark, M Cobal, E Cocca, A Connolly, J Conway, J Cooper, M Cordelli, D Costanzo, J Cranshaw, D Cronin-Hennessy

Abstract:

We measure the relative rate of production of orbitally excited (L=1) states of B mesons (B**) by observing their decays into Bπ±. We reconstruct B mesons through semileptonic decay channels using data collected pp̄ collisions at √s= 1.8 TeV. The fraction of light B mesons that are produced as L= 1B** states is measured to be 0.28±0.06(stat)±0.03(syst). We also measure the collective mass of the B** states, and quantify the result by quoting the (model-dependent) mass of the lowest B** state to be m(B1) = 5.71 ±0.02GeV/c2. ©2001 The American Physical Society.

Quasi-model-independent search for new physics at large transverse momentum

Physical Review D Particles Fields Gravitation and Cosmology 64:1 (2001)

Authors:

VM Abazov, B Abbott, A Abdesselam, M Abolins, V Abramov, BS Acharya, DL Adams, M Adams, SN Ahmed, GD Alexeev, GA Alves, N Amos, EW Anderson, MM Baarmand, VV Babintsev, L Babukhadia, TC Bacon, A Baden, B Baldin, PW Balm, S Banerjee, E Barberis, P Baringer, J Barreto, JF Bartlett, U Bassler, D Bauer, A Bean, M Begel, A Belyaev, SB Beri, G Bernardi, I Bertram, A Besson, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, M Bhattacharjee, G Blazey, S Blessing, A Boehnlein, NI Bojko, F Borcherding, K Bos, A Brandt, R Breedon, G Briskin, R Brock, G Brooijmans, A Bross, D Buchholz, M Buehler, V Buescher, VS Burtovoi, JM Butler, F Canelli, W Carvalho, D Casey, Z Casilum, H Castilla-Valdez, D Chakraborty, KM Chan, SV Chekulaev, DK Cho, S Choi, S Chopra, JH Christenson, M Chung, D Claes, AR Clark, J Cochran, L Coney, B Connolly, WE Cooper, D Coppage, MAC Cummings, D Cutts, GA Davis, K Davis, K De, SJ Jong, K Del Signore, M Demarteau, R Demina, P Demine, D Denisov, SP Denisov, S Desai, HT Diehl, M Diesburg, G Loreto, S Doulas, P Draper, Y Ducros, LV Dudko, S Duensing, L Duflot, SR Dugad, A Dyshkant

Abstract:

We apply a quasi-model-independent strategy (“SLEUTH”) to search for new high [Formula Presented] physics in ≈100 [Formula Presented] of [Formula Presented] collisions at [Formula Presented] collected by the DØ experiment during 1992–1996 at the Fermilab Tevatron. Over 32 [Formula Presented] [Formula Presented] [Formula Presented] and [Formula Presented] exclusive final states are systematically analyzed for hints of physics beyond the standard model. Simultaneous sensitivity to a variety of models predicting new phenomena at the electroweak scale is demonstrated by testing the method on a particular signature in each set of final states. No evidence of new high [Formula Presented] physics is observed in the course of this search, and we find that 89% of an ensemble of hypothetical similar experimental runs would have produced a final state with a candidate signal more interesting than the most interesting observed in these data. © 2001 The American Physical Society.

Search for dilepton signatures from minimal low-energy supergravity in pp̄ collisions at √s = 1.8 TeV

Physical Review D 63:9 (2001)

Authors:

B Abbott, M Abolins, V Abramov, BS Acharya, DL Adams, M Adams, GA Alves, N Amos, EW Anderson, MM Baarmand, VV Babintsev, L Babukhadia, A Baden, B Baldin, PW Balm, S Banerjee, J Bantly, E Barberis, P Baringer, JF Bartlett, U Bassler, A Bean, M Begel, A Belyaev, SB Beri, G Bernardi, I Bertram, A Besson, VA Bezzubov, PC Bhat, V Bhatnagar, M Bhattacharjee, G Blazey, S Blessing, A Boehnlein, NI Bojko, F Borcherding, A Brandt, R Breedon, G Briskin, R Brock, G Brooijmans, A Bross, D Buchholz, M Buehler, V Buescher, VS Burtovoi, JM Butler, F Canelli, W Carvalho, D Casey, Z Casilum, H Castilla-Valdez, D Chakraborty, KM Chan, SV Chekulaev, DK Cho, S Choi, S Chopra, BC Choudhary, JH Christenson, M Chung, D Claes, AR Clark, J Cochran, L Coney, B Connolly, WE Cooper, D Coppage, MAC Cummings, D Cutts, OI Dahl, GA Davis, K Davis, K De, K Del Signore, M Demarteau, R Demina, P Demine, D Denisov, SP Denisov, S Desai, HT Diehl, M Diesburg, G Di Loreto, S Doulas, P Draper, Y Ducros, LV Dudko, S Duensing, SR Dugad, A Dyshkant, D Edmunds, J Ellison, VD Elvira, R Engelmann, S Eno, G Eppley, P Ermolov, OV Eroshin

Abstract:

We report on a search for supersymmetry using the DØ detector. The 1994-1996 data sample of √s = 1.8 TeV pp̄ collisions was analyzed for events containing two leptons (e or μ), two or more jets, and missing transverse energy. Assuming the minimal supergravity model, with A0 = 0 and μ < 0, various thresholds were employed to optimize the search. No events were found beyond expectation from the background. We set a lower limit at the 95% C.L. of 255 GeV/c2 for equal mass squarks and gluinos for tan β = 2, and present exclusion contours in the (m0, m1/2) plane for tan β = 2-6.

Search for first-generation scalar and vector leptoquarks

Physical Review D Particles Fields Gravitation and Cosmology 64:9 (2001)

Authors:

VM Abazov, B Abbott, A Abdesselam, M Abolins, V Abramov, BS Acharya, DL Adams, M Adams, SN Ahmed, GD Alexeev, GA Alves, N Amos, EW Anderson, Y Arnoud, MM Baarmand, VV Babintsev, L Babukhadia, TC Bacon, A Baden, B Baldin, PW Balm, S Banerjee, E Barberis, P Baringer, J Barreto, JF Bartlett, U Bassler, D Bauer, A Bean, M Begel, A Belyaev, SB Beri, G Bernardi, I Bertram, A Besson, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, M Bhattacharjee, G Blazey, S Blessing, A Boehnlein, NI Bojko, F Borcherding, K Bos, A Brandt, R Breedon, G Briskin, R Brock, G Brooijmans, A Bross, D Buchholz, M Buehler, V Buescher, VS Burtovoi, JM Butler, F Canelli, W Carvalho, D Casey, Z Casilum, H Castilla-Valdez, D Chakraborty, KM Chan, SV Chekulaev, DK Cho, S Choi, S Chopra, JH Christenson, M Chung, D Claes, AR Clark, J Cochran, L Coney, B Connolly, WE Cooper, D Coppage, S Crépé-Renaudin, MAC Cummings, D Cutts, GA Davis, K Davis, K De, SJ Jong, K Del Signore, M Demarteau, R Demina, P Demine, D Denisov, SP Denisov, S Desai, HT Diehl, M Diesburg, G Loreto, S Doulas, P Draper, Y Ducros, LV Dudko, S Duensing, L Duflot

Abstract:

We describe a search for the pair production of first-generation scalar and vector leptoquarks in the [Formula Presented] and [Formula Presented] channels by the DØ Collaboration. The data are from the 1992–1996 [Formula Presented] run at [Formula Presented] at the Fermilab Tevatron collider. We find no evidence for leptoquark production; in addition, no kinematically interesting events are observed using relaxed selection criteria. The results from the [Formula Presented] and [Formula Presented] channels are combined with those from a previous DØ analysis of the [Formula Presented] channel to obtain 95% confidence level (C.L.) upper limits on the leptoquark pair-production cross section as a function of mass and of [Formula Presented] the branching fraction to a charged lepton. These limits are compared to next-to-leading-order theory to set 95% C.L. lower limits on the mass of a first-generation scalar leptoquark of 225, 204, and 79 [Formula Presented] for [Formula Presented] [Formula Presented] and 0, respectively. For vector leptoquarks with gauge (Yang-Mills) couplings, 95% C.L. lower limits of 345, 337, and 206 [Formula Presented] are set on the mass for [Formula Presented] [Formula Presented] and 0, respectively. Mass limits for vector leptoquarks are also set for anomalous vector couplings. © 2001 The American Physical Society.