Germany

C. Adolph

Italy

M.G. Alekseev

JINR

V. Yu. Alexakhin

Russia

Yu. Alexandrov

G.D. Alexeev

A. Amoroso

France

V. Andrieux

CERN

A. Austregesilo

Poland

B. Badełek

F. Balestra

J. Barth

G. Baum

Y. Bedfer

A. Berlin

J. Bernhard

R. Bertini

K. Bicker

J. Bieling

R. Birsa

J. Bisplinghoff

M. Boer

Portugal

P. Bordalo

F. Bradamante

C. Braun

A. Bravar

A. Bressan

M. Büchele

E. Burtin

L. Capozza

M. Chiosso

S.U. Chung

A. Cicuttin

M.L. Crespo

S. Dalla Torre

S.S. Dasgupta

India

S. Dasgupta

O. Yu. Denisov

S.V. Donskov

Japan

N. Doshita

V. Duic

W. Dünnweber

M. Dziewiecki

A. Efremov

C. Elia

P.D. Eversheim

W. Eyrich

M. Faessler

A. Ferrero

A. Filin

Czechia

M. Finger

M. Finger Jr.

H. Fischer

C. Franco

N. du Fresne von Hohenesche

J.M. Friedrich

V. Frolov

R. Garfagnini

F. Gautheron

O.P. Gavrichtchouk

S. Gerassimov

R. Geyer

M. Giorgi

I. Gnesi

B. Gobbo

S. Goertz

S. Grabmüller

A. Grasso

B. Grube

R. Gushterski

A. Guskov

T. Guthörl

F. Haas

D. von Harrach

F.H. Heinsius

F. Herrmann

C. Heß

F. Hinterberger

Ch. Höppner

N. Horikawa

N. d’Hose

S. Huber

S. Ishimoto

Yu. Ivanshin

T. Iwata

R. Jahn

V. Jary

P. Jasinski

R. Joosten

E. Kabuß

D. Kang

B. Ketzer

G.V. Khaustov

Yu. A. Khokhlov

Yu. Kisselev

F. Klein

K. Klimaszewski

J.H. Koivuniemi

V.N. Kolosov

K. Kondo

K. Königsmann

Erratum to: Hadron transverse momentum distributions in muon deep inelastic scattering at 160Â GeV/ c

A measurement of the azimuthal asymmetry in dihadron production in deep-inelastic scattering of muons on transversely polarised proton (NH 3 ) targets is presented. They provide independent access to the transversity distribution functions through the measurement of the Collins asymmetry in single hadron production. The data were taken in the year 2010 with the COMPASS spectrometer using a 160 GeV/c muon beam of the CERN SPS, increasing by a factor of about four the overall statistics with respect to the previously published data taken in the year 2007. The measured sizeable asymmetry is in good agreement with the published data. An approximate equality of the Collins asymmetry and the dihadron asymmetry is observed, suggesting a common physical mechanism in the underlying fragmentation.

R. Akhunzyanov

V. Anosov

R. Beck

M. Bodlak

Q. Curiel

O.Yu. Denisov

N. du Fresne von Hohenesche

M. Gorzellik

D. Hahne

R. Hashimoto

N. d'Hose

A. Ivanov

P. Joerg

Yu.A. Khokhlov

A high-statistics measurement of transverse spin effects in dihadron production from muon–proton semi-inclusive deep-inelastic scattering

Exclusive production of Ï0 mesons was studied at the COMPASS experiment by scattering 160Â GeV/c muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured as a function of Q2 , xBj , or pT2 . The sinÏS asymmetry is found to be â0.019Â±0.008(stat.)Â±0.003(syst.) . All other asymmetries are also found to be of small magnitude and consistent with zero within experimental uncertainties. Very recent calculations using a GPD-based model agree well with the present results. The data is interpreted as evidence for the existence of chiral-odd, transverse generalized parton distributions.

V.Yu. Alexakhin

Transverse target spin asymmetries in exclusive ρ0 muoproduction