European Physical Journal C: Particles and Fields (Dec 2020)

Two-particle correlations in azimuthal angle and pseudorapidity in central $$^7\hbox {Be}+{}^9\hbox {Be}$$ 7 Be + 9 Be collisions at the CERN Super Proton Synchrotron

  • A. Aduszkiewicz,
  • E. V. Andronov,
  • T. Antićić,
  • V. Babkin,
  • M. Baszczyk,
  • S. Bhosale,
  • A. Blondel,
  • M. Bogomilov,
  • A. Brandin,
  • A. Bravar,
  • W. Bryliński,
  • J. Brzychczyk,
  • M. Buryakov,
  • O. Busygina,
  • A. Bzdak,
  • H. Cherif,
  • M. Ćirković,
  • M. Csanad,
  • J. Cybowska,
  • T. Czopowicz,
  • A. Damyanova,
  • N. Davis,
  • M. Deliyergiyev,
  • M. Deveaux,
  • A. Dmitriev,
  • W. Dominik,
  • P. Dorosz,
  • J. Dumarchez,
  • R. Engel,
  • G. A. Feofilov,
  • L. Fields,
  • Z. Fodor,
  • A. Garibov,
  • M. Gaździcki,
  • O. Golosov,
  • V. Golovatyuk,
  • M. Golubeva,
  • K. Grebieszkow,
  • F. Guber,
  • A. Haesler,
  • S. N. Igolkin,
  • S. Ilieva,
  • A. Ivashkin,
  • S. R. Johnson,
  • K. Kadija,
  • N. Kargin,
  • E. Kashirin,
  • M. Kiełbowicz,
  • V. A. Kireyeu,
  • V. Klochkov,
  • V. I. Kolesnikov,
  • D. Kolev,
  • A. Korzenev,
  • V. N. Kovalenko,
  • S. Kowalski,
  • M. Koziel,
  • A. Krasnoperov,
  • W. Kucewicz,
  • M. Kuich,
  • A. Kurepin,
  • D. Larsen,
  • A. László,
  • T. V. Lazareva,
  • M. Lewicki,
  • K. Łojek,
  • V. V. Lyubushkin,
  • M. Maćkowiak-Pawłowska,
  • Z. Majka,
  • B. Maksiak,
  • A. I. Malakhov,
  • A. Marcinek,
  • A. D. Marino,
  • K. Marton,
  • H.-J. Mathes,
  • T. Matulewicz,
  • V. Matveev,
  • G. L. Melkumov,
  • A. O. Merzlaya,
  • B. Messerly,
  • Ł. Mik,
  • S. Morozov,
  • S. Mrówczyński,
  • Y. Nagai,
  • M. Naskręt,
  • V. Ozvenchuk,
  • V. Paolone,
  • O. Petukhov,
  • R. Płaneta,
  • P. Podlaski,
  • B. A. Popov,
  • B. Porfy,
  • M. Posiadała-Zezula,
  • D. S. Prokhorova,
  • D. Pszczel,
  • S. Puławski,
  • J. Puzović,
  • M. Ravonel,
  • R. Renfordt,
  • D. Röhrich,
  • E. Rondio,
  • M. Roth,
  • B. T. Rumberger,
  • M. Rumyantsev,
  • A. Rustamov,
  • M. Rybczynski,
  • A. Rybicki,
  • A. Sadovsky,
  • K. Schmidt,
  • I. Selyuzhenkov,
  • A. Yu. Seryakov,
  • P. Seyboth,
  • M. Słodkowski,
  • P. Staszel,
  • G. Stefanek,
  • J. Stepaniak,
  • M. Strikhanov,
  • H. Ströbele,
  • T. Šuša,
  • A. Taranenko,
  • A. Tefelska,
  • D. Tefelski,
  • V. Tereshchenko,
  • A. Toia,
  • R. Tsenov,
  • L. Turko,
  • R. Ulrich,
  • M. Unger,
  • D. Uzhva,
  • F. F. Valiev,
  • D. Veberič,
  • V. V. Vechernin,
  • A. Wickremasinghe,
  • Z. Włodarczyk,
  • K. Wojcik,
  • O. Wyszyński,
  • E. D. Zimmerman,
  • R. Zwaska,
  • NA61/SHINE Collaboration

DOI
https://doi.org/10.1140/epjc/s10052-020-08675-4
Journal volume & issue
Vol. 80, no. 12
pp. 1 – 20

Abstract

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Abstract A measurement of charged hadron pair correlations in two-dimensional $$\Delta \eta \Delta \phi $$ Δ η Δ ϕ space is presented. The analysis is based on total 30 million central Be + Be collisions observed in the NA61/SHINE detector at the CERN SPS for incident beam momenta of 19A, 30A, 40A, 75A, and 150A $$\text {Ge} \text {V}/c$$ Ge / c . Measurements were carried out for unlike-sign and like-sign charge hadron pairs independently. The $$C(\Delta \eta ,\Delta \phi )$$ C ( Δ η , Δ ϕ ) correlation functions were compared with results from a similar analysis on p + p interactions at similar beam momenta per nucleon. General trends of the back-to-back correlations are similar in central Be + Be collisions and p + p interactions, but are suppressed in magnitude due to the increased combinatorial background. Predictions from the Epos and UrQMD models are compared to the measurements. Evolution of an enhancement around $$(\Delta \eta ,\Delta \phi ) = (0,0)$$ ( Δ η , Δ ϕ ) = ( 0 , 0 ) with incident energy is observed in central Be + Be collisions. It is not predicted by both models and almost non-existing in proton–proton collisions at the same momentum per nucleon.