Evidence for collectivity in pp collisions at the LHC

Measurements of two- and multi-particle angular correlations in pp collisions at root s = 5, 7, and 13TeV are presented as a function of charged-particle multiplicity. The data, corresponding to integrated luminosities of 1.0 pb(-1) (5 TeV), 6.2 pb(-1) (7 TeV), and 0.7 pb(-1) (13 TeV), were collected using the CMS detector at the LHC. The second-order (v(2)) and third-order (v(3)) azimuthal anisotropy harmonics of unidentified charged particles, as well as v(2) of K-S(0) and Lambda/(Lambda) over bar particles, are extracted from long-range two-particle correlations as functions of particle multiplicity and transverse momentum. For high-multiplicity pp events, a mass ordering is observed for the v(2) values of charged hadrons (mostly pions), K-S(0), and Lambda/(Lambda) over bar, with lighter particle species exhibiting a stronger azimuthal anisotropy signal below pT approximate to GeV/c. For 13 TeV data, the v(2) signals are also extracted from four- and six-particle correlations for th...

Keywords:

CMS / Physics / Heavy ion / Ridge / Correlation / pp

Source:
Physics Letters B, 2017, 765, 193-220

Funding / projects:

BMWFW (Austria), FWF (Austria), FNRS (Belgium), FWO (Belgium), CNPq (Brazil), CAPES (Brazil), FAPERJ (Brazil), FAPESP (Brazil), MES (Bulgaria), CERN, CAS (China), MOST (China), NSFC (China), COLCIENCIAS (Colombia), MSES (Croatia), CSF (Croatia), RPF (Cyprus), SENESCYT (Ecuador), ERDF (Estonia), MoER (Estonia), ERC IUT (Estonia), Academy of Finland, MEC (Finland), HIP (Finland), CEA (France), CNRS/IN2P3 (France), BMBF, Germany, DFG (Germany), HGF (Germany), GSRT (Greece), OTKA (Hungary), NIH (Hungary), DAE (India), DST (India), IPM (Iran), SFI (Ireland), INFN (Italy), MSIP (Republic of Korea), NRF (Republic of Korea), LAS (Lithuania), MOE (Malaysia), UM (Malaysia), BUAP (Mexico), CINVESTAV (Mexico), CONACYT (Mexico), LNS (Mexico), SEP (Mexico), UASLP-FAI (Mexico), MBIE (New Zealand), PAEC (Pakistan), MSHE (Poland), NSC (Poland), FCT (Portugal), JINR (Dubna), MON (Russia), RosAtom (Russia), RAS (Russia), RFBR (Russia), MESTD (Serbia), SEIDI (Spain), CPAN (Spain), Swiss Funding Agencies (Switzerland), MST (Taipei), ThEPCenter (Thailand), IPST (Thailand), STAR (Thailand), NSTDA (Thailand), TUBITAK (Turkey), TAEK (Turkey), NASU (Ukraine), SFFR (Ukraine), STFC (United Kingdom), DOE (USA), NSF (USA), Marie-Curie program (European Union), European Research Council (European Union), EPLANET (European Union), Leventis Foundation, Alfred P. Sloan Foundation, Alexander von Humboldt Foundation, Belgian Federal Science Policy Office, Fonds pour la Formation a la Recherche dans lIndustrie et dans lAgriculture (FRIA-Belgium), Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium), Ministry of Education, Youth and Sports (MEYS) of the Czech Republic, Council of Science and Industrial Research, India, HOMING PLUS program of the Foundation for Polish Science, European Union, Regional Development Fund, Mobility Plus program of the Ministry of Science and Higher Education, OPUS program of the National Science Center (Poland) [2014/13/B/ST2/02543, Sonata-bis DEC-2012/07/E/ST2/01406], Thalis program - EU-ESF, Aristeia program - EU-ESF, Greek NSRF, National Priorities Research Program by Qatar National Research Fund, Programa Clarin-COFUND del Principado de Asturias, Rachadapisek Sompot Fund for Postdoctoral Fellowship, Chulalongkorn University (Thailand), Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand), Welch Foundation [C-1845]

DOI: 10.1016/j.physletb.2016.12.009

ISSN: 0370-2693; 1873-2445

WoS: 000393627800025

Scopus: 2-s2.0-85007251845

[ Google Scholar ]



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TY  - JOUR
AU  - Khachatryan, V.
AU  - Adžić, Petar
AU  - Ćirković, Predrag
AU  - Devetak, Damir
AU  - Đorđević, Miloš
AU  - Milošević, Jovan
AU  - Reković, Vladimir
AU  - Milenović, Predrag
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1419
AB  - Measurements of two- and multi-particle angular correlations in pp collisions at root s = 5, 7, and 13TeV are presented as a function of charged-particle multiplicity. The data, corresponding to integrated luminosities of 1.0 pb(-1) (5 TeV), 6.2 pb(-1) (7 TeV), and 0.7 pb(-1) (13 TeV), were collected using the CMS detector at the LHC. The second-order (v(2)) and third-order (v(3)) azimuthal anisotropy harmonics of unidentified charged particles, as well as v(2) of K-S(0) and Lambda/(Lambda) over bar particles, are extracted from long-range two-particle correlations as functions of particle multiplicity and transverse momentum. For high-multiplicity pp events, a mass ordering is observed for the v(2) values of charged hadrons (mostly pions), K-S(0), and Lambda/(Lambda) over bar, with lighter particle species exhibiting a stronger azimuthal anisotropy signal below pT approximate to GeV/c. For 13 TeV data, the v(2) signals are also extracted from four- and six-particle correlations for the first time in pp collisions, with comparable magnitude to those from two-particle correlations. These observations are similar to those seen in pPb and PbPb collisions, and support the interpretation of a collective origin for the observed long-range correlations in high-multiplicity pp collisions. (C) 2016 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license.
T2  - Physics Letters B
T1  - Evidence for collectivity in pp collisions at the LHC
VL  - 765
SP  - 193
EP  - 220
DO  - 10.1016/j.physletb.2016.12.009
ER  -

@article{
author = "Khachatryan, V. and Adžić, Petar and Ćirković, Predrag and Devetak, Damir and Đorđević, Miloš and Milošević, Jovan and Reković, Vladimir and Milenović, Predrag",
year = "2017",
abstract = "Measurements of two- and multi-particle angular correlations in pp collisions at root s = 5, 7, and 13TeV are presented as a function of charged-particle multiplicity. The data, corresponding to integrated luminosities of 1.0 pb(-1) (5 TeV), 6.2 pb(-1) (7 TeV), and 0.7 pb(-1) (13 TeV), were collected using the CMS detector at the LHC. The second-order (v(2)) and third-order (v(3)) azimuthal anisotropy harmonics of unidentified charged particles, as well as v(2) of K-S(0) and Lambda/(Lambda) over bar particles, are extracted from long-range two-particle correlations as functions of particle multiplicity and transverse momentum. For high-multiplicity pp events, a mass ordering is observed for the v(2) values of charged hadrons (mostly pions), K-S(0), and Lambda/(Lambda) over bar, with lighter particle species exhibiting a stronger azimuthal anisotropy signal below pT approximate to GeV/c. For 13 TeV data, the v(2) signals are also extracted from four- and six-particle correlations for the first time in pp collisions, with comparable magnitude to those from two-particle correlations. These observations are similar to those seen in pPb and PbPb collisions, and support the interpretation of a collective origin for the observed long-range correlations in high-multiplicity pp collisions. (C) 2016 The Author. Published by Elsevier B.V. This is an open access article under the CC BY license.",
journal = "Physics Letters B",
title = "Evidence for collectivity in pp collisions at the LHC",
volume = "765",
pages = "193-220",
doi = "10.1016/j.physletb.2016.12.009"
}

Khachatryan, V., Adžić, P., Ćirković, P., Devetak, D., Đorđević, M., Milošević, J., Reković, V.,& Milenović, P.. (2017). Evidence for collectivity in pp collisions at the LHC. in Physics Letters B, 765, 193-220.
https://doi.org/10.1016/j.physletb.2016.12.009

Khachatryan V, Adžić P, Ćirković P, Devetak D, Đorđević M, Milošević J, Reković V, Milenović P. Evidence for collectivity in pp collisions at the LHC. in Physics Letters B. 2017;765:193-220.
doi:10.1016/j.physletb.2016.12.009 .

Khachatryan, V., Adžić, Petar, Ćirković, Predrag, Devetak, Damir, Đorđević, Miloš, Milošević, Jovan, Reković, Vladimir, Milenović, Predrag, "Evidence for collectivity in pp collisions at the LHC" in Physics Letters B, 765 (2017):193-220,
https://doi.org/10.1016/j.physletb.2016.12.009 . .