Elsevier

Physics Letters B

Volume 843, 10 August 2023, 137950
Physics Letters B

Collins and Sivers transverse-spin asymmetries in inclusive muoproduction of ρ0 mesons

https://doi.org/10.1016/j.physletb.2023.137950Get rights and content
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Abstract

The production of vector mesons in deep inelastic scattering is an interesting yet scarcely explored channel to study the transverse spin structure of the nucleon and the spin-dependence of fragmentation. The COMPASS collaboration has performed the first measurement of the Collins and Sivers asymmetries for inclusively produced ρ0 mesons. The analysis is based on the data set collected in deep inelastic scattering in 2010 using a 160GeV/c μ+ beam impinging on a transversely polarized NH3 target. The ρ0 mesons are selected from oppositely charged hadron pairs, and the asymmetries are extracted as a function of the Bjorken-x variable, the transverse momentum of the pair and the fraction of the energy z carried by the pair. Indications for positive Collins and Sivers asymmetries are observed.

Keywords

SIDIS
Spin
Fragmentation
Collins asymmetry
Sivers asymmetry

Data availability

The authors are unable or have chosen not to specify which data has been used.

Cited by (0)

A

Supported by MEYS, Grants LM2015058, LM2018104 and LTT17018 and Charles University Grant PRIMUS/22/SCI/017 (Czech Republic).

B

Supported by BMBF - Bundesministerium für Bildung und Forschung (Germany).

C

Supported by B. Sen fund (India).

D

Supported by the Israel Academy of Sciences and Humanities (Israel).

E

Supported by MEXT and JSPS, Grants 18002006, 20540299, 18540281 and 26247032, the Daiko and Yamada Foundations (Japan).

F

Supported by NCN, Grant 2020/37/B/ST2/01547 (Poland).

G

Supported by FCT, Grants CERN/FIS-PAR/0022/2019 and CERN/FIS-PAR/0016/2021 (Portugal).

H

Supported by the Ministry of Science and Technology, Taiwan.

I

Supported by the National Science Foundation, Grant no. PHY-1506416 (USA).

1

Supported by the European Union's Horizon 2020 research and innovation programme under grant agreement STRONG–2020 - No 824093.

2

Supported by ANR, France with P2IO LabEx (ANR-10-LABX-0038) in the framework “Investissements d'Avenir” (ANR-11-IDEX-0003-01).

3

Supported by the DFG Research Training Group Programmes 1102 and 2044 (Germany).

4

Retired from Ludwig-Maximilians-Universität, 80539 München, Germany.

d1

Supported by the DFG cluster of excellence ‘Origin and Structure of the Universe’ (www.universe-cluster.de) (Germany).

e

Also at ORIGINS Excellence Cluster, 85748 Garching, Germany.

f

Also at Institut für Theoretische Physik, Universität Tübingen, 72076 Tübingen, Germany.

g

Present address: NISER, Centre for Medical and Radiation Physics, Bubaneswar, India.

h

Also at University of Eastern Piedmont, 15100 Alessandria, Italy.

h1

Supported by the Funds for Research 2019-22 of the University of Eastern Piedmont.

i

Also at Chubu University, Kasugai, Aichi 487-8501, Japan.

j

Also at KEK, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.

k

Also at Dept. of Physics, Pusan National University, Busan 609-735, Republic of Korea.

k1

Also at Physics Dept., Brookhaven National Laboratory, Upton, NY 11973, USA.

l

Also at Dept. of Physics, National Central University, 300 Jhongda Road, Jhongli 32001, Taiwan.

m

Also at Dept. of Physics, National Kaohsiung Normal University, Kaohsiung County 824, Taiwan.

Deceased.