J/ψ polarization in p+p collisions at s=200 GeV in STAR

STAR Collaboration

doi:10.1016/j.physletb.2014.10.049

J/ψ polarization in p+p collisions at s=200 GeV in STAR

STAR Collaboration

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

12 Scopus citations

Abstract

We report on a polarization measurement of inclusive J/ψ mesons in the di-electron decay channel at mid-rapidity at 2 < pT < 6 GeV/c in p + p collisions at √s = 200 GeV. Data were taken with the STAR detector at RHIC. The J/ψ polarization measurement should help to distinguish between the different models of the J/ψ production mechanism since they predict different pT dependences of the J/ψ polarization. In this analysis, J/ψ polarization is studied in the helicity frame. The polarization parameter λθ measured at RHIC becomes smaller towards high pT , indicating more longitudinal J/ψ polarization as pT increases. The result is compared with predictions of presently available models.

Original language	English
Pages (from-to)	180-188
Number of pages	9
Journal	Physics Letters B
Volume	739
DOIs	https://doi.org/10.1016/j.physletb.2014.10.049
State	Published - Dec 2 2014
Externally published	Yes

Funding

We thank the RHIC Operations Group and RCF at BNL , the NERSC Center at LBNL , the KISTI Center in Korea and the Open Science Grid consortium for providing resources and support. This work was supported in part by the Offices of NP and HEP within the U.S. DOE Office of Science , the U.S. NSF , CNRS/IN2P3 , FAPESP CNPq of Brazil , Ministry of Ed. and Sci. of the Russian Federation , NNSFC, CAS , MoST and MoE of China , the Korean Research Foundation , GA and MSMT of the Czech Republic , FIAS of Germany , DAE , DST , and CSIR of India , National Science Centre of Poland , National Research Foundation ( NRF-2012004024 ), Ministry of Sci., Ed. and Sports of the Rep. of Croatia , and RosAtom of Russia .

Funders	Funder number
FAPESP CNPq
MSMT
Ministry of Sci.
MOE of China
U.S. NSF	CNRS/IN2P3
National Science Foundation	1352081, 1067907
Office of Science
Department of Science and Technology, Ministry of Science and Technology, India
Council of Scientific and Industrial Research, India
Department of Atomic Energy, Government of India
National Natural Science Foundation of China
Chinese Academy of Sciences
National Research Foundation of Korea	NRF-2012004024
Narodowe Centrum Nauki
Ministry of Science and Technology, Taiwan
Council on grants of the President of the Russian Federation

Keywords

Charmonia
Polarization
RHIC
STAR
Spin alignment

Access to Document

10.1016/j.physletb.2014.10.049

Cite this

@article{fc1d415ccc3145ee8c35c642940b79b1,

title = "J/ψ polarization in p+p collisions at s=200 GeV in STAR",

abstract = "We report on a polarization measurement of inclusive J/ψ mesons in the di-electron decay channel at mid-rapidity at 2 < pT < 6 GeV/c in p + p collisions at √s = 200 GeV. Data were taken with the STAR detector at RHIC. The J/ψ polarization measurement should help to distinguish between the different models of the J/ψ production mechanism since they predict different pT dependences of the J/ψ polarization. In this analysis, J/ψ polarization is studied in the helicity frame. The polarization parameter λθ measured at RHIC becomes smaller towards high pT , indicating more longitudinal J/ψ polarization as pT increases. The result is compared with predictions of presently available models.",

keywords = "Charmonia, Polarization, RHIC, STAR, Spin alignment",

author = "{STAR Collaboration} and L. Adamczyk and Adkins, {J. K.} and G. Agakishiev and Aggarwal, {M. M.} and Z. Ahammed and I. Alekseev and J. Alford and Anson, {C. D.} and A. Aparin and D. Arkhipkin and Aschenauer, {E. C.} and Averichev, {G. S.} and J. Balewski and A. Banerjee and Z. Barnovska and Beavis, {D. R.} and R. Bellwied and A. Bhasin and Bhati, {A. K.} and P. Bhattarai and H. Bichsel and J. Bielcik and J. Bielcikova and Bland, {L. C.} and Bordyuzhin, {I. G.} and W. Borowski and J. Bouchet and Brandin, {A. V.} and Brovko, {S. G.} and S. B{\"u}ltmann and I. Bunzarov and Burton, {T. P.} and J. Butterworth and H. Caines and {Calder{\'o}n De La Barca S{\'a}nchez}, M. and D. Cebra and R. Cendejas and Cervantes, {M. C.} and P. Chaloupka and Z. Chang and S. Chattopadhyay and Chen, {H. F.} and Chen, {J. H.} and L. Chen and J. Cheng and M. Cherney and A. Chikanian and W. Christie and J. Chwastowski and J. Schambach",

note = "Publisher Copyright: {\textcopyright} 2014 The Authors.",

year = "2014",

month = dec,

day = "2",

doi = "10.1016/j.physletb.2014.10.049",

language = "English",

volume = "739",

pages = "180--188",

journal = "Physics Letters B",

issn = "0370-2693",

publisher = "Elsevier",

}

TY - JOUR

T1 - J/ψ polarization in p+p collisions at s=200 GeV in STAR

AU - STAR Collaboration

AU - Adamczyk, L.

AU - Adkins, J. K.

AU - Agakishiev, G.

AU - Aggarwal, M. M.

AU - Ahammed, Z.

AU - Alekseev, I.

AU - Alford, J.

AU - Anson, C. D.

AU - Aparin, A.

AU - Arkhipkin, D.

AU - Aschenauer, E. C.

AU - Averichev, G. S.

AU - Balewski, J.

AU - Banerjee, A.

AU - Barnovska, Z.

AU - Beavis, D. R.

AU - Bellwied, R.

AU - Bhasin, A.

AU - Bhati, A. K.

AU - Bhattarai, P.

AU - Bichsel, H.

AU - Bielcik, J.

AU - Bielcikova, J.

AU - Bland, L. C.

AU - Bordyuzhin, I. G.

AU - Borowski, W.

AU - Bouchet, J.

AU - Brandin, A. V.

AU - Brovko, S. G.

AU - Bültmann, S.

AU - Bunzarov, I.

AU - Burton, T. P.

AU - Butterworth, J.

AU - Caines, H.

AU - Calderón De La Barca Sánchez, M.

AU - Cebra, D.

AU - Cendejas, R.

AU - Cervantes, M. C.

AU - Chaloupka, P.

AU - Chang, Z.

AU - Chattopadhyay, S.

AU - Chen, H. F.

AU - Chen, J. H.

AU - Chen, L.

AU - Cheng, J.

AU - Cherney, M.

AU - Chikanian, A.

AU - Christie, W.

AU - Chwastowski, J.

AU - Schambach, J.

PY - 2014/12/2

Y1 - 2014/12/2

N2 - We report on a polarization measurement of inclusive J/ψ mesons in the di-electron decay channel at mid-rapidity at 2 < pT < 6 GeV/c in p + p collisions at √s = 200 GeV. Data were taken with the STAR detector at RHIC. The J/ψ polarization measurement should help to distinguish between the different models of the J/ψ production mechanism since they predict different pT dependences of the J/ψ polarization. In this analysis, J/ψ polarization is studied in the helicity frame. The polarization parameter λθ measured at RHIC becomes smaller towards high pT , indicating more longitudinal J/ψ polarization as pT increases. The result is compared with predictions of presently available models.

AB - We report on a polarization measurement of inclusive J/ψ mesons in the di-electron decay channel at mid-rapidity at 2 < pT < 6 GeV/c in p + p collisions at √s = 200 GeV. Data were taken with the STAR detector at RHIC. The J/ψ polarization measurement should help to distinguish between the different models of the J/ψ production mechanism since they predict different pT dependences of the J/ψ polarization. In this analysis, J/ψ polarization is studied in the helicity frame. The polarization parameter λθ measured at RHIC becomes smaller towards high pT , indicating more longitudinal J/ψ polarization as pT increases. The result is compared with predictions of presently available models.

KW - Charmonia

KW - Polarization

KW - RHIC

KW - STAR

KW - Spin alignment

UR - http://www.scopus.com/inward/record.url?scp=84910092408&partnerID=8YFLogxK

U2 - 10.1016/j.physletb.2014.10.049

DO - 10.1016/j.physletb.2014.10.049

M3 - Article

AN - SCOPUS:84910092408

SN - 0370-2693

VL - 739

SP - 180

EP - 188

JO - Physics Letters B

JF - Physics Letters B

ER -

J/ψ polarization in p+p collisions at s=200 GeV in STAR

Abstract

Funding

Keywords

Access to Document

Other files and links

Fingerprint

Cite this