Title
Event-shape and multiplicity dependence of freeze-out radii in pp collisions at √s = 7 TeV
Date Issued
01 September 2019
Access level
open access
Resource Type
journal article
Author(s)
Acharya S.
Adamová D.
Adhya S.P.
Adler A.
Adolfsson J.
Aggarwal M.M.
Aglieri Rinella G.
Agnello M.
Agrawal N.
Ahammed Z.
Ahmad S.
Ahn S.U.
Aiola S.
Akindinov A.
Al-Turany M.
Alam S.N.
Albuquerque D.S.D.
Aleksandrov D.
Alessandro B.
Alfanda H.M.
Alfaro Molina R.
Ali Y.
Alici A.
Alkin A.
Alme J.
Alt T.
Altenkamper L.
Altsybeev I.
Anaam M.N.
Andrei C.
Andreou D.
Andrews H.A.
Andronic A.
Angeletti M.
Anguelov V.
Anson C.
Antičić T.
Antinori F.
Antonioli P.
Anwar R.
Apadula N.
Aphecetche L.
Appelshäuser H.
Arcelli S.
Arnaldi R.
Arsene I.C.
Arslandok M.
Augustinus A.
Averbeck R.
Azmi M.D.
Badalá A.
Baek Y.W.
Bagnasco S.
Bailhache R.
Bala R.
Baldisseri A.
Ball M.
Baral R.C.
Barbera R.
Barioglio L.
Barnaföldi G.G.
Barnby L.S.
Barret V.
Bartalini P.
Barth K.
Bartsch E.
Bastid N.
Basu S.
Batigne G.
Batyunya B.
Batzing P.C.
Bearden I.G.
Beck H.
Bedda C.
Behera N.K.
Belikov I.
Bellini F.
Bello Martinez H.
Bellwied R.
Beltran L.G.E.
Belyaev V.
Bencedi G.
Beole S.
Bercuci A.
Berdnikov Y.
Berenyi D.
Bertens R.A.
Berzano D.
Betev L.
Bhasin A.
Bhat I.R.
Bhatt H.
Bhattacharjee B.
Bhom J.
Bianchi A.
Bianchi L.
Bianchi N.
Bielčík J.
Bielčíková J.
Budker Institute for Nuclear Physics
Publisher(s)
Springer Science and Business Media Deutschland GmbH
Abstract
Two-particle correlations in high-energy collision experiments enable the extraction of particle source radii by using the Bose-Einstein enhancement of pion production at low relative momentum q ∝ 1/R. It was previously observed that in pp collisions at s = 7TeV the average pair transverse momentum kT range of such analyses is limited due to large background correlations which were attributed to mini-jet phenomena. To investigate this further, an event-shape dependent analysis of Bose-Einstein correlations for pion pairs is performed in this work. By categorizing the events by their transverse sphericity ST into spherical (ST > 0:7) and jet-like (ST < 0:3) events a method was developed that allows for the determination of source radii for much larger values of kT for the first time. Spherical events demonstrate little or no background correlations while jet-like events are dominated by them. This observation agrees with the hypothesis of a mini-jet origin of the non-femtoscopic background correlations and gives new insight into the physics interpretation of the kT dependence of the radii. The emission source size in spherical events shows a substantially diminished kT dependence, while jet-like events show indications of a negative trend with respect to kT in the highest multiplicity events. Regarding the emission source shape, the correlation functions for both event sphericity classes show good agreement with an exponential shape, rather than a Gaussian one.
Volume
2019
Issue
9
Language
English
OCDE Knowledge area
Física nuclear Astronomía Física de partículas, Campos de la Física
Scopus EID
2-s2.0-85074488241
Source
Journal of High Energy Physics
ISSN of the container
10298479
Sponsor(s)
National Science Foundation - 1719759 Science and Technology Facilities Council - ALICE
Sources of information: Directorio de Producción Científica Scopus