Λ c+ production in pp collisions at √s=7 TeV and in p-Pb collisions at √sNN=5.02 TeV

The ALICE collaboration

doi:10.1007/JHEP04(2018)108

Λ _c⁺ production in pp collisions at √s=7 TeV and in p-Pb collisions at √sNN=5.02 TeV

The ALICE collaboration

Relativistic Nuclear Physics

Research output: Contribution to journal › Article › peer-review

75 Scopus citations

Abstract

The p_T-differential production cross section of prompt Λ_c⁺ charmed baryons was measured with the ALICE detector at the Large Hadron Collider (LHC) in pp collisions at s=7 TeV and in p-Pb collisions at sNN=5.02 TeV at midrapidity. The Λ_c⁺ and Λ¯ _{c ¯} were reconstructed in the hadronic decay modes Λ_c⁺ → pK⁻π⁺, Λ_c⁺ → pK_S⁰ and in the semileptonic channel Λ_c⁺ → e⁺ν_eΛ (and charge conjugates). The measured values of the Λ_c⁺/D⁰ ratio, which is sensitive to the c-quark hadronisation mechanism, and in particular to the production of baryons, are presented and are larger than those measured previously in different colliding systems, centre-of-mass energies, rapidity and p_T intervals, where the Λ_c⁺ production process may differ. The results are compared with the expectations obtained from perturbative Quantum Chromodynamics calculations and Monte Carlo event generators. Neither perturbative QCD calculations nor Monte Carlo models reproduce the data, indicating that the fragmentation of heavy-flavour baryons is not well understood. The first measurement at the LHC of the Λ_c⁺ nuclear modification factor, R_pPb, is also presented. The R_pPb is found to be consistent with unity and with that of D mesons within the uncertainties, and consistent with a theoretical calculation that includes cold nuclear matter effects and a calculation that includes charm quark interactions with a deconfined medium.[Figure not available: see fulltext.]

Original language	English
Article number	108
Journal	Journal of High Energy Physics
Volume	2018
Issue number	4
DOIs	https://doi.org/10.1007/JHEP04(2018)108
State	Published - Apr 1 2018

Funding

Open Access, Copyright CERN, for the benefit of the ALICE Collaboration. Article funded by SCOAP3. The ALICE Collaboration would like to thank all its engineers and technicians for their invaluable contributions to the construction of the experiment and the CERN accelerator teams for the outstanding performance of the LHC complex. The ALICE Collaboration gratefully acknowledges the resources and support provided by all Grid centres and the Worldwide LHC Computing Grid (WLCG) collaboration. The ALICE Collaboration acknowledges the following funding agencies for their support in building and running the ALICE detector: A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute) Foundation (ANSL), State Committee of Science and World Federation of Scientists (WFS), Armenia; Austrian Academy of Sciences and Nationalstiftung für Forschung, Tech-nologie und Entwicklung, Austria; Ministry of Communications and High Technologies, National Nuclear Research Center, Azerbaijan; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Universidade Federal do Rio Grande do Sul (UFRGS), Financiadora de Estudos e Projetos (Finep) and Fundac¸ão de Amparo à Pesquisa do Estado de São Paulo (FAPESP), Brazil; Ministry of Science & Technology of China (MSTC), National Natural Science Foundation of China (NSFC) and Ministry of Education of China (MOEC), China; Ministry of Science, Education and Sport and Croatian Science Foundation, Croatia; Ministry of Education, Youth and Sports of the Czech Republic, Czech Republic; The Danish Council for Independent Research — Natural Sciences, the Carls-berg Foundation and Danish National Research Foundation (DNRF), Denmark; Helsinki Institute of Physics (HIP), Finland; Commissariat à l’Energie Atomique (CEA) and In-stitut National de Physique Nucléaire et de Physique des Particules (IN2P3) and Centre National de la Recherche Scientifique (CNRS), France; Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie (BMBF) and GSI Helmholtzzentrum für Schwe-rionenforschung GmbH, Germany; General Secretariat for Research and Technology, Ministry of Education, Research and Religions, Greece; National Research, Development and Innovation Office, Hungary; Department of Atomic Energy Government of India (DAE), Department of Science and Technology, Government of India (DST), University Grants Commission, Government of India (UGC) and Council of Scientific and Industrial Research (CSIR), India; Indonesian Institute of Science, Indonesia; Centro Fermi - Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi and Istituto Nazionale di Fisica Nu-cleare (INFN), Italy; Institute for Innovative Science and Technology, Nagasaki Institute of Applied Science (IIST), Japan Society for the Promotion of Science (JSPS) KAKENHI and Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan; Consejo Nacional de Ciencia (CONACYT) y Tecnología, through Fondo de Co-operación Internacional en Ciencia y Tecnología (FONCICYT) and Dirección General de Asuntos del Personal Academico (DGAPA), Mexico; Nederlandse Organisatie voor Weten-schappelijk Onderzoek (NWO), Netherlands; The Research Council of Norway, Norway; Commission on Science and Technology for Sustainable Development in the South (COM-SATS), Pakistan; Pontificia Universidad Católica del Perú, Peru; Ministry of Science and Higher Education and National Science Centre, Poland; Korea Institute of Science and Technology Information and National Research Foundation of Korea (NRF), Republic of Korea; Ministry of Education and Scientific Research, Institute of Atomic Physics and Romanian National Agency for Science, Technology and Innovation, Romania; Joint In-

Keywords

Heavy Ion Experiments
Quark gluon plasma

Access to Document

10.1007/JHEP04(2018)108

Cite this

@article{7ed8ebed79bb4d4e90c9f07f78003426,

title = "Λ c+ production in pp collisions at √s=7 TeV and in p-Pb collisions at √sNN=5.02 TeV",

abstract = "The pT-differential production cross section of prompt Λc+ charmed baryons was measured with the ALICE detector at the Large Hadron Collider (LHC) in pp collisions at s=7 TeV and in p-Pb collisions at sNN=5.02 TeV at midrapidity. The Λc+ and Λ¯ c ¯ were reconstructed in the hadronic decay modes Λc+ → pK−π+, Λc+ → pKS0 and in the semileptonic channel Λc+ → e+νeΛ (and charge conjugates). The measured values of the Λc+/D0 ratio, which is sensitive to the c-quark hadronisation mechanism, and in particular to the production of baryons, are presented and are larger than those measured previously in different colliding systems, centre-of-mass energies, rapidity and pT intervals, where the Λc+ production process may differ. The results are compared with the expectations obtained from perturbative Quantum Chromodynamics calculations and Monte Carlo event generators. Neither perturbative QCD calculations nor Monte Carlo models reproduce the data, indicating that the fragmentation of heavy-flavour baryons is not well understood. The first measurement at the LHC of the Λc+ nuclear modification factor, RpPb, is also presented. The RpPb is found to be consistent with unity and with that of D mesons within the uncertainties, and consistent with a theoretical calculation that includes cold nuclear matter effects and a calculation that includes charm quark interactions with a deconfined medium.[Figure not available: see fulltext.]",

keywords = "Heavy Ion Experiments, Quark gluon plasma",

author = "{The ALICE collaboration} and S. Acharya and Acosta, {F. T.} and D. Adamov{\'a} and J. Adolfsson and Aggarwal, {M. M.} and {Aglieri Rinella}, G. and M. Agnello and N. Agrawal and Z. Ahammed and Ahn, {S. U.} and S. Aiola and A. Akindinov and M. Al-Turany and Alam, {S. N.} and Albuquerque, {D. S.D.} and D. Aleksandrov and B. Alessandro and {Alfaro Molina}, R. and Y. Ali and A. Alici and A. Alkin and J. Alme and T. Alt and L. Altenkamper and I. Altsybeev and C. Andrei and D. Andreou and Andrews, {H. A.} and A. Andronic and M. Angeletti and V. Anguelov and C. Anson and T. Anti{\v c}i{\'c} and F. Antinori and P. Antonioli and N. Apadula and L. Aphecetche and H. Appelsh{\"a}user and S. Arcelli and R. Arnaldi and Arnold, {O. W.} and Arsene, {I. C.} and M. Arslandok and B. Audurier and A. Augustinus and R. Averbeck and Azmi, {M. D.} and F. Bock and Read, {K. F.} and Schmidt, {N. V.}",

note = "Publisher Copyright: {\textcopyright} 2018, The Author(s).",

year = "2018",

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day = "1",

doi = "10.1007/JHEP04(2018)108",

language = "English",

volume = "2018",

journal = "Journal of High Energy Physics",

issn = "1126-6708",

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TY - JOUR

T1 - Λ c+ production in pp collisions at √s=7 TeV and in p-Pb collisions at √sNN=5.02 TeV

AU - The ALICE collaboration

AU - Acharya, S.

AU - Acosta, F. T.

AU - Adamová, D.

AU - Adolfsson, J.

AU - Aggarwal, M. M.

AU - Aglieri Rinella, G.

AU - Agnello, M.

AU - Agrawal, N.

AU - Ahammed, Z.

AU - Ahn, S. U.

AU - Aiola, S.

AU - Akindinov, A.

AU - Al-Turany, M.

AU - Alam, S. N.

AU - Albuquerque, D. S.D.

AU - Aleksandrov, D.

AU - Alessandro, B.

AU - Alfaro Molina, R.

AU - Ali, Y.

AU - Alici, A.

AU - Alkin, A.

AU - Alme, J.

AU - Alt, T.

AU - Altenkamper, L.

AU - Altsybeev, I.

AU - Andrei, C.

AU - Andreou, D.

AU - Andrews, H. A.

AU - Andronic, A.

AU - Angeletti, M.

AU - Anguelov, V.

AU - Anson, C.

AU - Antičić, T.

AU - Antinori, F.

AU - Antonioli, P.

AU - Apadula, N.

AU - Aphecetche, L.

AU - Appelshäuser, H.

AU - Arcelli, S.

AU - Arnaldi, R.

AU - Arnold, O. W.

AU - Arsene, I. C.

AU - Arslandok, M.

AU - Audurier, B.

AU - Augustinus, A.

AU - Averbeck, R.

AU - Azmi, M. D.

AU - Bock, F.

AU - Read, K. F.

AU - Schmidt, N. V.

PY - 2018/4/1

Y1 - 2018/4/1

N2 - The pT-differential production cross section of prompt Λc+ charmed baryons was measured with the ALICE detector at the Large Hadron Collider (LHC) in pp collisions at s=7 TeV and in p-Pb collisions at sNN=5.02 TeV at midrapidity. The Λc+ and Λ¯ c ¯ were reconstructed in the hadronic decay modes Λc+ → pK−π+, Λc+ → pKS0 and in the semileptonic channel Λc+ → e+νeΛ (and charge conjugates). The measured values of the Λc+/D0 ratio, which is sensitive to the c-quark hadronisation mechanism, and in particular to the production of baryons, are presented and are larger than those measured previously in different colliding systems, centre-of-mass energies, rapidity and pT intervals, where the Λc+ production process may differ. The results are compared with the expectations obtained from perturbative Quantum Chromodynamics calculations and Monte Carlo event generators. Neither perturbative QCD calculations nor Monte Carlo models reproduce the data, indicating that the fragmentation of heavy-flavour baryons is not well understood. The first measurement at the LHC of the Λc+ nuclear modification factor, RpPb, is also presented. The RpPb is found to be consistent with unity and with that of D mesons within the uncertainties, and consistent with a theoretical calculation that includes cold nuclear matter effects and a calculation that includes charm quark interactions with a deconfined medium.[Figure not available: see fulltext.]

AB - The pT-differential production cross section of prompt Λc+ charmed baryons was measured with the ALICE detector at the Large Hadron Collider (LHC) in pp collisions at s=7 TeV and in p-Pb collisions at sNN=5.02 TeV at midrapidity. The Λc+ and Λ¯ c ¯ were reconstructed in the hadronic decay modes Λc+ → pK−π+, Λc+ → pKS0 and in the semileptonic channel Λc+ → e+νeΛ (and charge conjugates). The measured values of the Λc+/D0 ratio, which is sensitive to the c-quark hadronisation mechanism, and in particular to the production of baryons, are presented and are larger than those measured previously in different colliding systems, centre-of-mass energies, rapidity and pT intervals, where the Λc+ production process may differ. The results are compared with the expectations obtained from perturbative Quantum Chromodynamics calculations and Monte Carlo event generators. Neither perturbative QCD calculations nor Monte Carlo models reproduce the data, indicating that the fragmentation of heavy-flavour baryons is not well understood. The first measurement at the LHC of the Λc+ nuclear modification factor, RpPb, is also presented. The RpPb is found to be consistent with unity and with that of D mesons within the uncertainties, and consistent with a theoretical calculation that includes cold nuclear matter effects and a calculation that includes charm quark interactions with a deconfined medium.[Figure not available: see fulltext.]

KW - Heavy Ion Experiments

KW - Quark gluon plasma

UR - http://www.scopus.com/inward/record.url?scp=85048630586&partnerID=8YFLogxK

U2 - 10.1007/JHEP04(2018)108

DO - 10.1007/JHEP04(2018)108

M3 - Article

AN - SCOPUS:85048630586

SN - 1126-6708

VL - 2018

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

IS - 4

M1 - 108

ER -