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Determination of the e+e- → γγ (γ) cross-section at LEP 2

European Physical Journal C 37:4 (2004) 405-419

Authors:

J Abdallah, P Abreu, W Adam, P Adzic, T Albrecht, T Alderweireld, R Alemany-Fernandez, T Allmendinger, P Allport, U Amaldi, N Amapane, S Amato, E Anashkin, A Andreazza, S Andringa, N Anjos, P Antilogus, WD Apel, Y Arnoud, S Ask, B Asman, E Augustin, A Augustinus, P Baillon, A Ballestrero, P Bambade, R Barbier, D Bardin, G Barker, A Baroncelli, M Battaglia, M Baubillier, KH Becks, M Begalli, A Behrmann, E Ben-Haim, N Benekos, A Benvenuti, C Berat, M Berggren, L Berntzon, D Bertrand, M Besancon, N Besson, D Bloch, M Blom, M Bluj, M Bonesini, M Boonekamp, L Booth, G Borisov, O Botner, B Bouquet, V Bowcock, I Boyko, M Bracko, R Brenner, E Brodet, P Bruckman, M Brunet, L Bugge, P Buschmann, M Calvi, T Camporesi, V Canale, F Carena, N Castro, F Cavallo, M Chapkin, P Charpentier, P Checchia, R Chierici, P Chliapnikov, J Chudoba, U Chung, K Cieslik, P Collins, R Contri, G Cosme, F Cossutti, J Costa, D Crennell, J Cuevas, J D'Hondt, J Dalmau, T Da Silva, W Da Silva, G Della Ricca, A De Angelis, W De Boer, C De Clercq, B De Lotto, N De Maria, A De Min, L De Paula, L Di Ciaccio, A Di Simone, K Doroba, J Drees, M Dris

Abstract:

A test of the benchmark QED process e+e- → γγ(γ) is reported, using the data collected with the DELPHI detector at LEP 2. The data analysed were recorded at centre-of-mass energies ranging from 161 GeV to 208 GeV and correspond to a total integrated luminosity of 656.4 pb-1. The Born cross-section for the process e +e- → γγ(γ) was determined, confirming the validity of QED at the highest energies ever attained in electron-positron collisions. Lower limits on the parameters of a number of possible deviations from QED, predicted within theoretical frameworks expressing physics beyond the Standard Model, were derived. © Springer-Verlag/ Società Italiana di Fisica 2004.

Erratum: Search for supersymmetric particles assuming R-parity non-conservation in e+e- collisions at √s = 192 to 208 GeV (The European Physical Journal C (2004) 36 (1-23) DOI: 10.1140/epjc/s2004-01881-6)

European Physical Journal C 37:1 (2004) 129-131

Authors:

J Abdallah, P Abreu, W Adam, P Adzic, T Albrecht, T Alderweireld, R Alemany-Fernandez, T Allmendinger, P Allport, U Amaldi, N Amapane, S Amato, E Anashkin, A Andreazza, S Andringa, N Anjos, P Antilogus, WD Apel, Y Arnoud, S Ask, B Asman, E Augustin, A Augustinus, P Baillon, A Ballestrero, P Bambade, R Barbier, D Bardin, J Barker, A Baroncelli, M Battaglia, M Baubillier, KH Becks, M Begalli, A Behrmann, E Ben-Haim, N Benekos, A Benvenuti, C Berat, M Berggren, L Berntzon, D Bertrand, M Besancon, N Besson, D Bloch, M Blom, M Bluj, M Bonesini, M Boonekamp, L Booth, G Borisov, O Botner, B Bouquet, V Bowcock, I Boyko, M Bracko, R Brenner, E Brodet, P Bruckman, M Brunet, L Bugge, P Buschmann, M Calvi, T Camporesi, V Canale, F Carena, N Castro, F Cavallo, M Chapkin, P Charpentier, P Checchia, R Chierici, P Chliapnikov, J Chudoba, U Chung, K Cieslik, P Collins, R Contri, G Cosme, F Cossutti, J Costa, D Crennell, J Cuevas, J D'Hondt, J Dalmau, T da Silva, W da Silva, G della Ricca, A de Angelis, W de Boer, C de Clercq, B de Lotto, N de Maria, A de Min, L de Paula, L di Ciaccio, A di Simone, K Doroba, J Drees, M Dris

Erratum: b-tagging in DELPHI at LEP (European Physical Journal C (2004) 32 (185-208) DOI 10.1140/epjc/s2003-01441-8)

European Physical Journal C 32:2 (2004) 299-301

Authors:

J Abdallah, P Abreu, W Adam, T Adye, P Adzic, T Albrecht, T Alderweireld, R Alemany-Fernandez, T Allmendinger, PP Allport, S Almehed, U Amaldi, N Amapane, S Amato, E Anashkin, A Andreazza, S Andringa, N Anjos, P Antilogus, WD Apel, Y Arnoud, S Ask, B Asman, JE Augustin, A Augustinus, P Baillon, A Ballestrero, P Bambade, R Barbier, D Bardin, G Barker, A Baroncelli, M Bates, M Battaglia, M Baubillier, KH Becks, M Begalli, A Behrmann, N Benekos, A Benvenuti, C Berat, M Berggren, L Berntzon, D Bertrand, M Besancon, N Besson, J Bibby, P Biffi, D Bloch, M Blom, M Bonesini, M Boonekamp, PSL Booth, G Borisov, O Botner, B Bouquet, TJV Bowcock, I Boyko, M Bracko, P Branchini, R Brenner, E Brodet, P Bruckman, JM Brunet, L Bugge, P Buschmann, M Caccia, M Calvi, T Camporesi, V Canale, F Carena, N Castro, F Cavallo, V Chabaud, M Chapkin, P Charpentier, P Checchia, R Chierici, P Chliapnikov, J Chudoba, SU Chung, K Cieslik, P Collins, R Contri, G Cosme, F Cossutti, MJ Costa, F Couchot, B Crawley, D Crennell, J Cuevas, B D'Almagne, J D'Hondt, J Dalmau, T da Silva, W Da Silva, G Della Ricca, A de Angelis, W de Boer, C de Clercq

Measurement of the branching fraction for B±→χ c0K±

Physical Review D 69:7 (2004)

Authors:

B Aubert, R Barate, D Boutigny, JM Gaillard, A Hicheur, Y Karyotakis, JP Lees, P Robbe, V Tisserand, A Zghiche, A Palano, A Pompili, JC Chen, ND Qi, G Rong, P Wang, YS Zhu, G Eigen, I Ofte, B Stugu, GS Abrams, AW Borgland, AB Breon, DN Brown, J Button-Shafer, RN Cahn, E Charles, CT Day, MS Gill, AV Gritsan, Y Groysman, RG Jacobsen, RW Kadel, J Kadyk, LT Kerth, YG Kolomensky, JF Kral, G Kukartsev, C LeClerc, ME Levi, G Lynch, LM Mir, PJ Oddone, TJ Orimoto, M Pripstein, NA Roe, A Romosan, MT Ronan, VG Shelkov, AV Telnov, WA Wenzel, K Ford, TJ Harrison, CM Hawkes, DJ Knowles, SE Morgan, RC Penny, AT Watson, NK Watson, K Goetzen, T Held, H Koch, B Lewandowski, M Pelizaeus, K Peters, H Schmuecker, M Steinke, NR Barlow, JT Boyd, N Chevalier, WN Cottingham, MP Kelly, TE Latham, C Mackay, FF Wilson, K Abe, T Cuhadar-Donszelmann, C Hearty, TS Mattison, JA McKenna, D Thiessen, P Kyberd, AK McKemey, VE Blinov, AD Bukin, VB Golubev, VN Ivanchenko, EA Kravchenko, AP Onuchin, SI Serednyakov, YI Skovpen, EP Solodov, AN Yushkov, D Best, M Bruinsma, M Chao, D Kirkby, AJ Lankford, M Mandelkern, RK Mommsen

Abstract:

We present a measurement of the branching fraction of the decay B ±→χc0K± sample of 89×106 BBÌ„ pairs collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. The χc0 meson is reconstructed through its two-body decays toÏ€+ Ï€- and K+K-. We measure B(B± → χc0K±) ×Β(χ c0→϶Ä+Ï€-) = [1.32-027 +0.28(stat)±0.26(syst)] × 10-6 and B(B ±→ χc0K±) × B(χc0 →K+K-) = [1.49 -0.34+0.36(stat) ±0.22(syst)] × 10 -6. Using the known values for the χc0 decays branching fractions, we combine these results to obtain Î’(B ± →χc0K±) = (2.7±0.7)× 10-4. © 2004 The American Physical Society.

Measurement of

European Physical Journal C 33:2 (2004) 213-232

Authors:

J Abdallah, P Abreu, W Adam, P Adzic, T Albrecht, T Alderweireld, R Alemany-Fernandez, T Allmendinger, P Allport, U Amaldi, N Amapane, S Amato, E Anashkin, A Andreazza, S Andringa, N Anjos, P Antilogus, WD Apel, Y Arnoud, S Ask, B Asman, E Augustin, A Augustinus, P Baillon, A Ballestrero, P Bambade, R Barbier, D Bardin, G Barker, A Baroncelli, M Battaglia, M Baubillier, KH Becks, M Begalli, A Behrmann, E Ben-Haim, N Benekos, A Benvenuti, C Berat, M Berggren, L Berntzon, D Bertrand, M Besancon, N Besson, D Bloch, M Blom, M Bluj, M Bonesini, M Boonekamp, L Booth, G Borisov, O Botner, B Bouquet, V Bowcock, I Boyko, M Bracko, R Brenner, E Brodet, P Bruckman, M Brunet, L Bugge, P Buschmann, M Calvi, T Camporesi, V Canale, F Carena, N Castro, F Cavallo, M Chapkin, P Charpentier, P Checchia, R Chierici, P Chliapnikov, J Chudoba, U Chung, K Cieslik, P Collins, R Contri, G Cosme, F Cossutti, J Costa, D Crennell, J Cuevas, J D'Hondt, J Dalmau, T da Silva, W Da Silva, G Della Ricca, A de Angelis, W de Boer, C de Clercq, B de Lotto, N de Maria, A de Min, L de Paula, L di Ciaccio, A di Simone, K Doroba, J Drees, M Dris

Abstract:

Data from Z decays in DELPHI have been searched for Bd 0 → D*+â„“-νℓ with the D*+ decaying to D0Ï€+ and D0 → K-Ï€+, K-Ï€ +Ï€+Ï€- or K-Ï€ +(Ï€0). These events are used to measure the CKM matrix element |Vcb| and the form factor slope, ÏA1 2: ℱD* (1) |Vcb| = 0.0392 ± 0.0018 ± 0.0023; ÏA12 = 1.32 ± 0.15 ± 0.33 corresponding to a branching fraction: BR(Bd 0 → D*+â„“-νℓ) = (5.90 ± 0.22 ± 0.50)%. Combining these and previous DELPHI measurements gives: ℱD* (1) |Vcb| = 0.0377 ± 0.0011 ± 0.0019, ÏA12 = 1.39 ± 0.10 ± 0.33 and BR(Bd0 → D* +â„“-νℓ) = (5.39 ± 0.11 ± 0.34)% Using ℱD* (1) = 0.91 ± 0.04, yields: |Vcbl = 0.0414 ± 0.0012(stat.) ± 0.0021(syst.) ± 0.0018(theory). The b-quark semileptonic branching fraction into a D*+ emitted from higher mass charmed excited states has also been measured to be: BR(b → D*+³Ýâ„“-ν â„“) = (0.67 ± 0.08 ± 0.10)%.