Precision measurement of forward Z boson production in proton-proton collisions at $$ \sqrt{\mathrm{s}} $$ = 13 TeV
R. Aaij, A. S. W. Abdelmotteleb, C. Abellán Beteta, F. Abudinén, T. Ackernley, B. Adeva, M. Adinolfi, H. Afsharnia, C. Agapopoulou, C. Aidala, S. Aiola, Z. Ajaltouni, S. Akar, J. Albrecht, F. Alessio, M. Alexander, A. Alfonso Albero, Z. Aliouche, Georgy Alkhazov, P. Álvarez Cartelle, S. Amato, J. L. Amey, Y. Amhis, L. An, L. Anderlini, M. Andersson, A. Andreianov, M. Andreotti, F. Archilli, A. Artamonov, M. Artuso, K. Arzymatov, E. Aslanides, M. Atzeni, B. Audurier, S. Bachmann, M. Bachmayer, J.J. Back, P. Baladrón Rodríguez, V. Balagura, W. Baldini, J. Baptista Leite, M. Barbetti, R. J. Barlow, S. Barsuk, W. Barter, M. Bartolini, F. Baryshnikov, J. M. Basels, S. Bashir, G. Bassi, B. Batsukh, A. Battig, A. Bay, A. Beck, M. Becker, F. Bedeschi, I. Bediaga, A. Beiter, V. Belavin, S. Belin, V. Bellée, K. Belous, I. Belov, I. Belyaev, G. Bencivenni, A. Berezhnoy, A. Berezhnoy, R. Bernet, D. Berninghoff, H. C. Bernstein, C. Bertella, A. Bertolin, C. Betancourt, F. Betti, Ia. Bezshyiko, S. Bhasin, J. Bhom, L. Bian, M. S. Bieker, N. V. Biesuz, S. Bifani, P. Billoir, A. Biolchini, M. Birch, F. C. R. Bishop, A. Bitadze, A. Bizzeti, M. Bjørn, M. P. Blago, T. Blake, F. Blanc, S. Blusk, D. Bobulska, J. A. Boelhauve, O. Boente García, T. Boettcher, A. S. Boldyrev, A. Bondar, N. Bondar
Abstract
A bstract A precision measurement of the Z boson production cross-section at $$ \sqrt{\mathrm{s}} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msqrt><mml:mi>s</mml:mi></mml:msqrt></mml:math> = 13 TeV in the forward region is presented, using pp collision data collected by the LHCb detector, corresponding to an integrated luminosity of 5.1 fb − 1 . The production cross-section is measured using Z → μ + μ − events within the fiducial region defined as pseudorapidity 2 . 0 < η < 4 . 5 and transverse momentum p T > 20 GeV /c for both muons and dimuon invariant mass 60 < M μμ < 120 GeV /c 2 . The integrated cross-section is determined to be $$ \sigma \left(Z\to {\mu}^{+}{\mu}^{-}\right)=196.4\pm 0.2\pm 1.6\pm 3.9\ \mathrm{pb}, $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>σ</mml:mi><mml:mfenced><mml:mrow><mml:mi>Z</mml:mi><mml:mo>→</mml:mo><mml:msup><mml:mi>μ</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>μ</mml:mi><mml:mo>−</mml:mo></mml:msup></mml:mrow></mml:mfenced><mml:mo>=</mml:mo><mml:mn>196.4</mml:mn><mml:mo>±</mml:mo><mml:mn>0.2</mml:mn><mml:mo>±</mml:mo><mml:mn>1.6</mml:mn><mml:mo>±</mml:mo><mml:mn>3.9</mml:mn><mml:mspace/><mml:mi>pb</mml:mi><mml:mo>,</mml:mo></mml:math> where the first uncertainty is statistical, the second is systematic, and the third is due to the luminosity determination. The measured results are in agreement with theoretical predictions within uncertainties.