Production of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">Υ</mml:mi><mml:mo>(</mml:mo><mml:mi>n</mml:mi><mml:mi>S</mml:mi><mml:mo>)</mml:mo></mml:mrow></mml:math> mesons in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Pb</mml:mi><mml:mo>+</mml:mo><mml:mi>Pb</mml:mi></mml:mrow></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>p</mml:mi><mml:mi>p</mml:mi></mml:mrow></mml:math> collisions at 5.02 TeV
G. Aad, B. Abbott, D. C. Abbott, K. Abeling, S. H. Abidi, A. Aboulhorma, H. Abramowicz, H. Abreu, Y. Abulaiti, A. C. Abusleme Hoffman, B. S. Acharya, B. Achkar, L. Adam, C. Adam Bourdarios, L. Adamczyk, L. Adámek, S. V. Addepalli, J. Adelman, A. Adıgüzel, S. Adorni, T. Adye, A. A. Affolder, Y. Afik, M. N. Agaras, J. Agarwala, A. Aggarwal, C. Agheorghiesei, J. A. Aguilar–Saavedra, A. Ahmad, F. Ahmadov, W. S. Ahmed, X. Ai, G. Aielli, I. Aizenberg, M. Akbiyik, T. P. A. Åkesson, A. V. Akimov, K. Al Khoury, G. L. Alberghi, J. Albert, P. Albicocco, M. J. Alconada Verzini, S. Alderweireldt, M. Aleksa, I. N. Aleksandrov, C. Alexa, T. Alexopoulos, A. Alfonsi, F. Alfonsi, M. Alhroob, B. Ali, S. Ali, M. Aliev, G. Alimonti, C. Allaire, B. M. M. Allbrooke, P. P. Allport, A. Aloisio, F. Alonso, C. Alpigiani, E. Alunno Camelia, M. Alvarez Estevez, M. G. Alviggi, Y. Amaral Coutinho, A. Ambler, C. Amelung, C. G. Ames, D. Amidei, S. P. Amor Dos Santos, S. Amoroso, K. R. Amos, Cherifa Sabrina Amrouche, V. Ananiev, C. Anastopoulos, N. Andari, T. Andeen, J. K. Anders, S. Y. Andrean, A. Andreazza, S. Angelidakis, A. Angerami, A. V. Anisenkov, A. Annovi, C. Antel, M. T. Anthony, E. Antipov, M. Antonelli, D. J. A. Antrim, F. Anulli, M. Aoki, J. A. Aparisi Pozo, M. A. Aparo, L. Aperio Bella, C. Appelt, N. Aranzabal, V. Araujo Ferraz, C. Arcangeletti, A. T. H. Arce, E. Arena, J-F. Arguin
Abstract
A measurement of the production of vector bottomonium states, $\ensuremath{\Upsilon}(\text{1S})$, $\ensuremath{\Upsilon}(\text{2S})$, and $\ensuremath{\Upsilon}(\text{3S})$, in $\mathrm{Pb}+\mathrm{Pb}$ and $pp$ collisions at a center-of-mass energy per nucleon pair of 5.02 TeV is presented. The data correspond to integrated luminosities of $1.38\phantom{\rule{4pt}{0ex}}{\text{nb}}^{\ensuremath{-}1}$ of $\mathrm{Pb}+\mathrm{Pb}$ data collected in 2018, $0.44\phantom{\rule{4pt}{0ex}}{\text{nb}}^{\ensuremath{-}1}$ of $\mathrm{Pb}+\mathrm{Pb}$ data collected in 2015, and $0.26\phantom{\rule{4pt}{0ex}}{\text{fb}}^{\ensuremath{-}1}$ of $pp$ data collected in 2017 by the ATLAS detector at the Large Hadron Collider. The measurements are performed in the dimuon decay channel for transverse momentum ${p}_{\text{T}}^{\ensuremath{\mu}\ensuremath{\mu}}<30\phantom{\rule{0.16em}{0ex}}\mathrm{GeV}$, absolute rapidity $|{y}^{\ensuremath{\mu}\ensuremath{\mu}}|<1.5$, and $\mathrm{Pb}+\mathrm{Pb}$ event centrality 0--80%. The production rates of the three bottomonium states in $\mathrm{Pb}+\mathrm{Pb}$ collisions are compared with those in $pp$ collisions to extract the nuclear modification factors as functions of event centrality, ${p}_{\text{T}}^{\ensuremath{\mu}\ensuremath{\mu}}$, and $|{y}^{\ensuremath{\mu}\ensuremath{\mu}}|$. In addition, the suppression of the excited states relative to the ground state is studied. The results are compared with theoretical model calculations.