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arXiv · 1210.4112

Measurement of the D+/- production asymmetry in 7 TeV pp collisions

LHCb collaboration·R. Aaij·C. Abellan Beteta·A. Adametz·B. Adeva·M. Adinolfi·C. Adrover·A. Affolder·Z. Ajaltouni·J. Albrecht·F. Alessio·M. Alexander·S. Ali·G. Alkhazov·P. Alvarez Cartelle·A. A. Alves Jr·S. Amato·Y. Amhis·L. Anderlini·J. Anderson·R. B. Appleby·O. Aquines Gutierrez·F. Archilli·A. Artamonov·M. Artuso·E. Aslanides·G. Auriemma·S. Bachmann·J. J. Back·C. Baesso·W. Baldini·R. J. Barlow·C. Barschel·S. Barsuk·W. Barter·A. Bates·Th. Bauer·A. Bay·J. Beddow·I. Bediaga·S. Belogurov·K. Belous·I. Belyaev·E. Ben-Haim·M. Benayoun·G. Bencivenni·S. Benson·J. Benton·A. Berezhnoy·R. Bernet·M. -O. Bettler·M. van Beuzekom·A. Bien·S. Bifani·T. Bird·A. Bizzeti·P. M. Bjørnstad·T. Blake·F. Blanc·C. Blanks·J. Blouw·S. Blusk·A. Bobrov·V. Bocci·A. Bondar·N. Bondar·W. Bonivento·S. Borghi·A. Borgia·T. J. V. Bowcock·C. Bozzi·T. Brambach·J. van den Brand·J. Bressieux·D. Brett·M. Britsch·T. Britton·N. H. Brook·H. Brown·A. Büchler-Germann·I. Burducea·A. Bursche·J. Buytaert·S. Cadeddu·O. Callot·M. Calvi·M. Calvo Gomez·A. Camboni·P. Campana·A. Carbone·G. Carboni·R. Cardinale·A. Cardini·H. Carranza-Mejia·L. Carson·K. Carvalho Akiba·G. Casse·M. Cattaneo·Ch. Cauet·M. Charles
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Abstract

The asymmetry in the production cross-section σof D+/- mesons, A_P = (σ(D+) - σ(D-))/(σ(D+) + σ(D-)), is measured in bins of pseudorapidity ηand transverse momentum p_T within the acceptance of the LHCb detector. The result is obtained with a sample of D+ -> K_S pi+ decays corresponding to an integrated luminosity of 1.0 fb^-1, collected in pp collisions at a centre of mass energy of 7 TeV at the Large Hadron Collider. When integrated over the kinematic range 2.0 < p_T < 18.0 GeV/c and 2.20 < η< 4.75, the production asymmetry is A_P = (-0.96+/-0.26+/-0.18)%. The uncertainties quoted are statistical and systematic, respectively. The result assumes that any direct CP violation in the D+ -> K_S pi+ decay is negligible. No significant dependence on ηor p_T is observed.

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LHCb collaboration, R. Aaij, C. Abellan Beteta, A. Adametz, B. Adeva, M. Adinolfi, C. Adrover, A. Affolder, Z. Ajaltouni, J. Albrecht, F. Alessio, M. Alexander, S. Ali, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves Jr, S. Amato, Y. Amhis, L. Anderlini, J. Anderson, R. B. Appleby, O. Aquines Gutierrez, F. Archilli, A. Artamonov, M. Artuso, E. Aslanides, G. Auriemma, S. Bachmann, J. J. Back, C. Baesso, W. Baldini, R. J. Barlow, C. Barschel, S. Barsuk, W. Barter, A. Bates, Th. Bauer, A. Bay, J. Beddow, I. Bediaga, S. Belogurov, K. Belous, I. Belyaev, E. Ben-Haim, M. Benayoun, G. Bencivenni, S. Benson, J. Benton, A. Berezhnoy, R. Bernet, M. -O. Bettler, M. van Beuzekom, A. Bien, S. Bifani, T. Bird, A. Bizzeti, P. M. Bjørnstad, T. Blake, F. Blanc, C. Blanks, J. Blouw, S. Blusk, A. Bobrov, V. Bocci, A. Bondar, N. Bondar, W. Bonivento, S. Borghi, A. Borgia, T. J. V. Bowcock, C. Bozzi, T. Brambach, J. van den Brand, J. Bressieux, D. Brett, M. Britsch, T. Britton, N. H. Brook, H. Brown, A. Büchler-Germann, I. Burducea, A. Bursche, J. Buytaert, S. Cadeddu, O. Callot, M. Calvi, M. Calvo Gomez, A. Camboni, P. Campana, A. Carbone, G. Carboni, R. Cardinale, A. Cardini, H. Carranza-Mejia, L. Carson, K. Carvalho Akiba, G. Casse, M. Cattaneo, Ch. Cauet, M. Charles. 2012-12-19. Measurement of the D+/- production asymmetry in 7 TeV pp collisions. https://doi.org/10.1016/j.physletb.2012.11.038

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