Improved measurement of the form factors in the decay lambda+c-->lambda + nue.
Using the CLEO detector at the Cornell Electron Storage Ring, we have studied the distribution of kinematic variables in the decay lambda(+)(c)lambda--> e(+)nu(e). By performing a four-dimensional maximum likelihood fit, we determine the form factor ratio, R= f(2)/f(1) = -0.31 +/- 0.05(stat) +/- 0.04(syst), the pole mass, M(pole) = [2.21 +/- 0.08(stat) +/- 0.14(syst)] GeV/c(2), and the decay asymmetry parameter of the lambda(+)(c), alpha (lambda(c)) = -0.86 +/-0.03(stat) +/- 0.02(syst), for q(2) = 0.67 (GeV/c(2))(2). We compare the angular distributions of the lambda(+)(c) and lambda(-)(c) and find no evidence for CP violation: A(lambda(c)) = (alpha(lambda(c)) + alpha (lambda(c)))/(alpha(lambda(c))-alpha(lambda(c))) = 0.00 +/- 0.03(stat) +/- 0.01(syst) +/- 0.02, where the third error is from the uncertainty in the world average of the CP-violating parameter, A(lambda), for ppi(-).
Hinson
J W
JW
Purdue University, West Lafayette, Indiana 47907, USA.
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G S
GS
Lee
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J
Miller
D H
DH
Pavlunin
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Rangarajan
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Sanghi
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Shibata
E I
EI
Shipsey
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IP
Cronin-Hennessy
D
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Park
C S
CS
Park
W
W
Thayer
J B
JB
Thorndike
E H
EH
Coan
T E
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Gao
Y S
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Liu
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F
Stroynowski
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Artuso
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M
Boulahouache
C
C
Blusk
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Dambasuren
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Dorjkhaidav
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Mountain
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Muramatsu
H
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Nandakumar
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Skwarnicki
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Stone
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Wang
J C
JC
Csorna
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Danko
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Bonvicini
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Cinabro
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Dubrovin
M
M
McGee
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Bornheim
A
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Lipeles
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Pappas
S P
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Shapiro
A
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Sun
W M
WM
Weinstein
A J
AJ
Briere
R A
RA
Chen
G P
GP
Ferguson
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Tatishvili
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Vogel
H
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Watkins
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Adam
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NE
Alexander
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JP
Berkelman
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Boisvert
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Cassel
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Duboscq
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Ecklund
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Ehrlich
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Galik
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Gibbons
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L
Gittelman
B
B
Gray
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Hartill
D L
DL
Heltsley
B K
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Hsu
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L
Jones
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CD
Kandaswamy
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Kreinick
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DL
Magerkurth
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A
Mahlke-Krüger
H
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Meyer
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Mistry
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Patterson
J R
JR
Peterson
D
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Pivarski
J
J
Richichi
S J
SJ
Riley
D
D
Sadoff
A J
AJ
Schwarthoff
H
H
Shepherd
M R
MR
Thayer
J G
JG
Urner
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Wilksen
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Warburton
A
A
Weinberger
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M
Athar
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Avery
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Breva-Newell
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Potlia
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Stoeck
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Yelton
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Benslama
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K
Cawlfield
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C
Eisenstein
B I
BI
Gollin
G D
GD
Karliner
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Lowrey
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Plager
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Sedlack
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C
Selen
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M
Thaler
J J
JJ
Williams
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Edwards
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KW
Besson
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D
Anderson
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Frolov
V V
VV
Gong
D T
DT
Kubota
Y
Y
Li
S Z
SZ
Poling
R
R
Smith
A
A
Stepaniak
C J
CJ
Urheim
J
J
Metreveli
Z
Z
Seth
K K
KK
Tomaradze
A
A
Zweber
P
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Ahmed
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Alam
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MS
Ernst
J
J
Jian
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L
Saleem
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M
Wappler
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Arms
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Eckhart
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E
Gan
K K
KK
Gwon
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Honscheid
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Kagan
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Kass
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Pedlar
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von Toerne
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Severini
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Dytman
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Mueller
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JA
Nam
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Savinov
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