Observation of the naive-T-odd Sivers effect in deep-inelastic scattering.
Azimuthal single-spin asymmetries of leptoproduced pions and charged kaons were measured on a transversely polarized hydrogen target. Evidence for a naive-T-odd, transverse-momentum-dependent parton distribution function is deduced from nonvanishing Sivers effects for pi(+), pi(0), and K(+/-), as well as in the difference of the pi(+) and pi(-) cross sections.
Airapetian
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A
Physikalisches Institut, Universität Giessen, 35392 Giessen, Germany.
Akopov
N
N
Akopov
Z
Z
Aschenauer
E C
EC
Augustyniak
W
W
Avetissian
A
A
Avetisyan
E
E
Bacchetta
A
A
Ball
B
B
Bianchi
N
N
Blok
H P
HP
Böttcher
H
H
Bonomo
C
C
Borissov
A
A
Bryzgalov
V
V
Burns
J
J
Capiluppi
M
M
Capitani
G P
GP
Cisbani
E
E
Ciullo
G
G
Contalbrigo
M
M
Dalpiaz
P F
PF
Deconinck
W
W
De Leo
R
R
De Nardo
L
L
De Sanctis
E
E
Diefenthaler
M
M
Di Nezza
P
P
Dreschler
J
J
Düren
M
M
Ehrenfried
M
M
Elbakian
G
G
Ellinghaus
F
F
Elschenbroich
U
U
Fabbri
R
R
Fantoni
A
A
Felawka
L
L
Frullani
S
S
Gabbert
D
D
Gapienko
G
G
Gapienko
V
V
Garibaldi
F
F
Gharibyan
V
V
Giordano
F
F
Gliske
S
S
Hadjidakis
C
C
Hartig
M
M
Hasch
D
D
Hill
G
G
Hillenbrand
A
A
Hoek
M
M
Holler
Y
Y
Hristova
I
I
Imazu
Y
Y
Ivanilov
A
A
Jackson
H E
HE
Jo
H S
HS
Joosten
S
S
Kaiser
R
R
Keri
T
T
Kinney
E
E
Kisselev
A
A
Korotkov
V
V
Kozlov
V
V
Kravchenko
P
P
Lagamba
L
L
Lamb
R
R
Lapikás
L
L
Lehmann
I
I
Lenisa
P
P
Linden-Levy
L A
LA
López Ruiz
A
A
Lorenzon
W
W
Lu
X-G
XG
Lu
X-R
XR
Ma
B-Q
BQ
Mahon
D
D
Makins
N C R
NC
Manaenkov
S I
SI
Manfré
L
L
Mao
Y
Y
Marianski
B
B
Martinez de la Ossa
A
A
Marukyan
H
H
Miller
C A
CA
Miyachi
Y
Y
Movsisyan
A
A
Murray
M
M
Mussgiller
A
A
Nappi
E
E
Naryshkin
Y
Y
Nass
A
A
Negodaev
M
M
Nowak
W-D
WD
Pappalardo
L L
LL
Perez-Benito
R
R
Reimer
P E
PE
Reolon
A R
AR
Riedl
C
C
Rith
K
K
Rosner
G
G
Rostomyan
A
A
Rubin
J
J
Ryckbosch
D
D
Salomatin
Y
Y
Sanftl
F
F
Schäfer
A
A
Schnell
G
G
Schüler
K P
KP
Seitz
B
B
Shibata
T-A
TA
Shutov
V
V
Stancari
M
M
Statera
M
M
Steijger
J J M
JJ
Stenzel
H
H
Stewart
J
J
Stinzing
F
F
Taroian
S
S
Terkulov
A
A
Trzcinski
A
A
Tytgat
M
M
Vandenbroucke
A
A
van der Nat
P B
PB
Van Haarlem
Y
Y
Van Hulse
C
C
Varanda
M
M
Veretennikov
D
D
Vikhrov
V
V
Vilardi
I
I
Vogel
C
C
Wang
S
S
Yaschenko
S
S
Ye
H
H
Ye
Z
Z
Yen
S
S
Yu
W
W
Zeiler
D
D
Zihlmann
B
B
Zupranski
P
P