Centre for Advanced Studies in Electronics Science and Technology

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Browsing Centre for Advanced Studies in Electronics Science and Technology by Author "Abbott, B."
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    Combinations of single-top-quark production cross-section measurements and |f < inf > LV < /inf > V < inf > tb < /inf > | determinations at √s = 7 and 8 TeV with the ATLAS and CMS experiments
    ( 2019-05-01) Aaboud, M. ; Aad, G. ; Abbott, B. ; Abbott, D. C. ; Abdinov, O. ; Abed Abud, A. ; Abhayasinghe, D. K. ; Abidi, S. H. ; AbouZeid, O. S. ; Abraham, N. L. ; Abramowicz, H. ; Abreu, H. ; Abulaiti, Y. ; Acharya, B. S. ; Adachi, S. ; Adam, L. ; Adamczyk, L. ; Adamek, L. ; Adelman, J. ; Adersberger, M. ; Adiguzel, A. ; Adorni, S. ; Adye, T. ; Affolder, A. A. ; Afik, Y. ; Agapopoulou, C. ; Agaras, M. N. ; Aggarwal, A. ; Agheorghiesei, C. ; Aguilar-Saavedra, J. A. ; Ahmadov, F. ; Ai, X. ; Aielli, G. ; Akatsuka, S. ; Åkesson, T. P.A. ; Akilli, E. ; Akimov, A. V. ; Al Khoury, K. ; Alberghi, G. L. ; Albert, J. ; Alconada Verzini, M. J. ; Alderweireldt, S. ; Aleksa, M. ; Aleksandrov, I. N. ; Alexa, C. ; Alexandre, D. ; Alexopoulos, T. ; Alfonsi, A. ; Alhroob, M. ; Ali, B. ; Alimonti, G. ; Alison, J. ; Alkire, S. P. ; Allaire, C. ; Allbrooke, B. M.M. ; Allen, B. W. ; Allport, P. P. ; Aloisio, A. ; Alonso, A. ; Alonso, F. ; Alpigiani, C. ; Alshehri, A. A. ; Alstaty, M. I. ; Alvarez Estevez, M. ; Alvarez Gonzalez, B. ; Álvarez Piqueras, D. ; Alviggi, M. G. ; Amaral Coutinho, Y. ; Ambler, A. ; Ambroz, L. ; Amelung, C. ; Amidei, D. ; Amor Dos Santos, S. P. ; Amoroso, S. ; Amrouche, C. S. ; An, F. ; Anastopoulos, C. ; Andari, N. ; Andeen, T. ; Anders, C. F. ; Anders, J. K. ; Andreazza, A. ; Andrei, V. ; Anelli, C. R. ; Angelidakis, S. ; Angelozzi, I. ; Angerami, A. ; Anisenkov, A. V. ; Annovi, A. ; Antel, C. ; Anthony, M. T. ; Antonelli, M. ; Antrim, D. J.A. ; Anulli, F. ; Aoki, M. ; Aparisi Pozo, J. A. ; Aperio Bella, L. ; Arabidze, G. ; Araque, J. P. ; Araujo Ferraz, V.
    This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at s = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb−1 at s = 7 TeV and 12.2 to 20.3 fb−1 at s = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 ± 5.7 pb and 87.7 ± 5.8 pb at s = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 ± 4.1 pb and 23.1 ± 3.6 pb at s = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 ± 1.4 pb at s = 8 TeV. The square of the magnitude of the CKM matrix element Vtb multiplied by a form factor fLV is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |Vtd|, |Vts| ≪ |Vtb|. All the |fLVVtb|2 determinations, extracted from individual ratios at s = 7 and 8 TeV, are combined, resulting in |fLVVtb| = 1.02 ± 0.04 (meas.) ± 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions.[Figure not available: see fulltext.].
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    Combined Measurement of the Higgs Boson Mass in pp Collisions at s =7 and 8 TeV with the ATLAS and CMS Experiments
    ( 2015-05-14) Aad, G. ; Abbott, B. ; Abdallah, J. ; Abdinov, O. ; Aben, R. ; Abolins, M. ; Abouzeid, O. S. ; Abramowicz, H. ; Abreu, H. ; Abreu, R. ; Abulaiti, Y. ; Acharya, B. S. ; Adamczyk, L. ; Adams, D. L. ; Adelman, J. ; Adomeit, S. ; Adye, T. ; Affolder, A. A. ; Agatonovic-Jovin, T. ; Aguilar-Saavedra, J. A. ; Ahlen, S. P. ; Ahmadov, F. ; Aielli, G. ; Akerstedt, H. ; Åkesson, T. P.A. ; Akimoto, G. ; Akimov, A. V. ; Alberghi, G. L. ; Albert, J. ; Albrand, S. ; Alconada Verzini, M. J. ; Aleksa, M. ; Aleksandrov, I. N. ; Alexa, C. ; Alexander, G. ; Alexopoulos, T. ; Alhroob, M. ; Alimonti, G. ; Alio, L. ; Alison, J. ; Alkire, S. P. ; Allbrooke, B. M.M. ; Allport, P. P. ; Aloisio, A. ; Alonso, A. ; Alonso, F. ; Alpigiani, C. ; Altheimer, A. ; Alvarez Gonzalez, B. ; Álvarez Piqueras, D. ; Alviggi, M. G. ; Amadio, B. T. ; Amako, K. ; Amaral Coutinho, Y. ; Amelung, C. ; Amidei, D. ; Amor Dos Santos, S. P. ; Amorim, A. ; Amoroso, S. ; Amram, N. ; Amundsen, G. ; Anastopoulos, C. ; Ancu, L. S. ; Andari, N. ; Andeen, T. ; Anders, C. F. ; Anders, G. ; Anders, J. K. ; Anderson, K. J. ; Andreazza, A. ; Andrei, V. ; Angelidakis, S. ; Angelozzi, I. ; Anger, P. ; Angerami, A. ; Anghinolfi, F. ; Anisenkov, A. V. ; Anjos, N. ; Annovi, A. ; Antonelli, M. ; Antonov, A. ; Antos, J. ; Anulli, F. ; Aoki, M. ; Aperio Bella, L. ; Arabidze, G. ; Arai, Y. ; Araque, J. P. ; Arce, A. T.H. ; Arduh, F. A. ; Arguin, J. F. ; Argyropoulos, S. ; Arik, M. ; Armbruster, A. J. ; Arnaez, O. ; Arnal, V. ; Arnold, H. ; Arratia, M. ; Arslan, O. ; Artamonov, A.
    A measurement of the Higgs boson mass is presented based on the combined data samples of the ATLAS and CMS experiments at the CERN LHC in the H→γγ and H→ZZ→4 decay channels. The results are obtained from a simultaneous fit to the reconstructed invariant mass peaks in the two channels and for the two experiments. The measured masses from the individual channels and the two experiments are found to be consistent among themselves. The combined measured mass of the Higgs boson is mH=125.09±0.21 (stat)±0.11 (syst) GeV.
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    Measurements of the Higgs boson production and decay rates and constraints on its couplings from a combined ATLAS and CMS analysis of the LHC pp collision data at √s = 7 and 8 TeV
    ( 2016-08-01) The ATLAS collaboration, ; Aad, G. ; Abbott, B. ; Abdallah, J. ; Abdinov, O. ; Abeloos, B. ; Aben, R. ; AbouZeid, O. S. ; Abraham, N. L. ; Abramowicz, H. ; Abreu, H. ; Abreu, R. ; Abulaiti, Y. ; Acharya, B. S. ; Adamczyk, L. ; Adams, D. L. ; Adelman, J. ; Adomeit, S. ; Adye, T. ; Affolder, A. A. ; Agatonovic-Jovin, T. ; Agricola, J. ; Aguilar-Saavedra, J. A. ; Ahlen, S. P. ; Ahmadov, F. ; Aielli, G. ; Akerstedt, H. ; Åkesson, T. P.A. ; Akimov, A. V. ; Alberghi, G. L. ; Albert, J. ; Albrand, S. ; Alconada Verzini, M. J. ; Aleksa, M. ; Aleksandrov, I. N. ; Alexa, C. ; Alexander, G. ; Alexopoulos, T. ; Alhroob, M. ; Aliev, M. ; Alimonti, G. ; Alison, J. ; Alkire, S. P. ; Allbrooke, B. M.M. ; Allen, B. W. ; Allport, P. P. ; Aloisio, A. ; Alonso, A. ; Alonso, F. ; Alpigiani, C. ; Alstaty, M. ; Alvarez Gonzalez, B. ; Álvarez Piqueras, D. ; Alviggi, M. G. ; Amadio, B. T. ; Amako, K. ; Amaral Coutinho, Y. ; Amelung, C. ; Amidei, D. ; Amor Dos Santos, S. P. ; Amorim, A. ; Amoroso, S. ; Amundsen, G. ; Anastopoulos, C. ; Ancu, L. S. ; Andari, N. ; Andeen, T. ; Anders, C. F. ; Anders, G. ; Anders, J. K. ; Anderson, K. J. ; Andreazza, A. ; Andrei, V. ; Angelidakis, S. ; Angelozzi, I. ; Anger, P. ; Angerami, A. ; Anghinolfi, F. ; Anisenkov, A. V. ; Anjos, N. ; Annovi, A. ; Antonelli, M. ; Antonov, A. ; Antos, J. ; Anulli, F. ; Aoki, M. ; Aperio Bella, L. ; Arabidze, G. ; Arai, Y. ; Araque, J. P. ; Arce, A. T.H. ; Arduh, F. A. ; Arguin, J. F. ; Argyropoulos, S. ; Arik, M. ; Armbruster, A. J. ; Armitage, L. J. ; Arnaez, O. ; Arnold, H. ; Arratia, M.
    Combined ATLAS and CMS measurements of the Higgs boson production and decay rates, as well as constraints on its couplings to vector bosons and fermions, are presented. The combination is based on the analysis of five production processes, namely gluon fusion, vector boson fusion, and associated production with a W or a Z boson or a pair of top quarks, and of the six decay modes H → ZZ, W W, γγ, ττ, bb, and μμ. All results are reported assuming a value of 125.09 GeV for the Higgs boson mass, the result of the combined measurement by the ATLAS and CMS experiments. The analysis uses the CERN LHC proton-proton collision data recorded by the ATLAS and CMS experiments in 2011 and 2012, corresponding to integrated luminosities per experiment of approximately 5 fb−1 at √s = 7 TeV and 20 fb−1 at √s = 8 TeV. The Higgs boson production and decay rates measured by the two experiments are combined within the context of three generic parameterisations: two based on cross sections and branching fractions, and one on ratios of coupling modifiers. Several interpretations of the measurements with more model-dependent parameterisations are also given. The combined signal yield relative to the Standard Model prediction is measured to be 1.09 ± 0.11. The combined measurements lead to observed significances for the vector boson fusion production process and for the H → ττ decay of 5.4 and 5.5 standard deviations, respectively. The data are consistent with the Standard Model predictions for all parameterisations considered.