Measurement of ep-->e' ppi+ pi- and baryon resonance analysis.
The cross section for the reaction ep-->e(')ppi(+)pi(-) was measured in the resonance region for 1.4<W<2.1 GeV and 0.5<Q2<1.5 GeV(2)/c(2) using the CLAS detector at Jefferson Laboratory. The data show resonant structures not visible in previous experiments. The comparison of our data to a phenomenological prediction using available information on N(*) and Delta states shows an evident discrepancy. A better description of the data is obtained either by a sizable change of the properties of the P13(1720) resonance or by introducing a new baryon state, not reported in published analyses.
Ripani
M
M
INFN, Sezione di Genova, 16146 Genova, Italy.
Burkert
V D
VD
Mokeev
V
V
Battaglieri
M
M
De Vita
R
R
Golovach
E
E
Taiuti
M
M
Adams
G
G
Anciant
E
E
Anghinolfi
M
M
Asavapibhop
B
B
Audit
G
G
Auger
T
T
Avakian
H
H
Bagdasaryan
H
H
Ball
J P
JP
Barrow
S
S
Beard
K
K
Bektasoglu
M
M
Bellis
M
M
Berman
B L
BL
Bianchi
N
N
Biselli
A S
AS
Boiarinov
S
S
Bonner
B E
BE
Bouchigny
S
S
Bradford
R
R
Branford
D
D
Briscoe
W J
WJ
Brooks
W K
WK
Calarco
J R
JR
Carman
D S
DS
Carnahan
B
B
Cazes
A
A
Cetina
C
C
Ciciani
L
L
Cole
P L
PL
Coleman
A
A
Cords
D
D
Corvisiero
P
P
Crabb
D
D
Crannell
H
H
Cummings
J P
JP
De Sanctis
E
E
Degtyarenko
P V
PV
Denizli
H
H
Dennis
L
L
Dharmawardane
K V
KV
Djalali
C
C
Dodge
G E
GE
Doughty
D
D
Dragovitsch
P
P
Dugger
M
M
Dytman
S
S
Eckhause
M
M
Egiyan
H
H
Egiyan
K S
KS
Elouadrhiri
L
L
Empl
A
A
Fatemi
R
R
Fedotov
G
G
Feldman
G
G
Feuerbach
R J
RJ
Ficenec
J
J
Forest
T A
TA
Funsten
H
H
Gaff
S J
SJ
Gai
M
M
Garçon
M
M
Gavalian
G
G
Gilad
S
S
Gilfoyle
G P
GP
Giovanetti
K L
KL
Girard
P
P
Griffioen
K
K
Guidal
M
M
Guillo
M
M
Guo
L
L
Gyurjyan
V
V
Hadjidakis
C
C
Hardie
J
J
Heddle
D
D
Heimberg
P
P
Hersman
F W
FW
Hicks
K
K
Hicks
R S
RS
Holtrop
M
M
Hu
J
J
Hyde-Wright
C E
CE
Ishkhanov
B
B
Ito
M M
MM
Jenkins
D
D
Joo
K
K
Kelley
J H
JH
Kellie
J D
JD
Khandaker
M
M
Kim
K Y
KY
Kim
K
K
Kim
W
W
Klein
A
A
Klein
F J
FJ
Klimenko
A V
AV
Klusman
M
M
Kossov
M
M
Kramer
L H
LH
Kuang
Y
Y
Kuhn
S E
SE
Kuhn
J
J
Lachniet
J
J
Laget
J M
JM
Lawrence
D
D
Li
Ji
J
Livingston
K
K
Longhi
A
A
Lukashin
K
K
Manak
J J
JJ
Marchand
C
C
McAleer
S
S
McCarthy
J
J
McNabb
J W C
JW
Mecking
B A
BA
Mestayer
M D
MD
Meyer
C A
CA
Mikhailov
K
K
Minehart
R
R
Mirazita
M
M
Miskimen
R
R
Morand
L
L
Morrow
S A
SA
Mozer
M U
MU
Muccifora
V
V
Mueller
J
J
Murphy
L Y
LY
Mutchler
G S
GS
Napolitano
J
J
Nasseripour
R
R
Nelson
S O
SO
Niccolai
S
S
Niculescu
G
G
Niculescu
I
I
Niczyporuk
B B
BB
Niyazov
R A
RA
Nozar
M
M
O'Rielly
G V
GV
Opper
A K
AK
Osipenko
M
M
Park
K
K
Pasyuk
E
E
Peterson
G
G
Philips
S A
SA
Pivnyuk
N
N
Pocanic
D
D
Pogorelko
O
O
Polli
E
E
Pozdniakov
S
S
Preedom
B M
BM
Price
J W
JW
Prok
Y
Y
Protopopescu
D
D
Qin
L M
LM
Quinn
B
B
Raue
B A
BA
Riccardi
G
G
Ricco
G
G
Ritchie
B G
BG
Ronchetti
F
F
Rossi
P
P
Rowntree
D
D
Rubin
P D
PD
Sabatié
F
F
Sabourov
K
K
Salgado
C
C
Santoro
J P
JP
Sapunenko
V
V
Schumacher
R A
RA
Serov
V S
VS
Shafi
A
A
Sharabian
Y G
YG
Shaw
J
J
Simionatto
S
S
Skabelin
A V
AV
Smith
E S
ES
Smith
L C
LC
Sober
D I
DI
Spraker
M
M
Stavinsky
A
A
Stepanyan
S
S
Stoler
P
P
Strakovsky
I I
II
Taylor
S
S
Tedeschi
D J
DJ
Thoma
U
U
Thompson
R
R
Todor
L
L
Ungaro
M
M
Vineyard
M F
MF
Vlassov
A V
AV
Wang
K
K
Weinstein
L B
LB
Weller
H
H
Weygand
D P
DP
Whisnant
C S
CS
Wolin
E
E
Wood
M H
MH
Yegneswaran
A
A
Yun
J
J
Zhang
B
B
Zhao
J
J
Zhou
Z
Z