Improved direct measurement of A(b) and A(c) at the Z(0) pole using a lepton tag.
The parity violation parameters A(b) and A(c) of the Zb(b) and Zc(c) couplings have been measured directly, using the polar angle dependence of the polarized cross sections at the Z(0) pole. Bottom and charmed hadrons were tagged via their semileptonic decays. Both the electron and muon analyses take advantage of new multivariate techniques to increase the analyzing power. Based on the 1993-1998 SLD sample of 550,000 Z(0) decays produced with highly polarized electron beams, we measure A(b) = 0.919+/-0.030(stat)+/-0.024(syst), and A(c) = 0.583+/-0.055(stat)+/-0.055(syst).
Abe
Kenji
K
Nagoya University Chikusa-ku, Nagoya, 464 Japan.
Abe
Koya
K
Abe
T
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Adam
I
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Akimoto
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Aston
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Baird
K G
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Baltay
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Band
H R
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Barklow
T L
TL
Bauer
J M
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Bellodi
G
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Berger
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Blaylock
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Bogart
J R
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Bower
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Brau
J E
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Breidenbach
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Bugg
W M
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Burke
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Burnett
T H
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Burrows
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Calcaterra
A
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Cassell
R
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Chou
A
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Cohn
H O
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Coller
J A
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Convery
M R
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Cook
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Cowan
R F
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Crawford
G
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Damerell
C J S
CJ
Daoudi
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de Groot
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de Sangro
R
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Dong
D N
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Doser
M
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Dubois
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Erofeeva
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Eschenburg
V
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Fahey
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Falciai
D
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Fernandez
J P
JP
Flood
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Frey
R
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Hart
E L
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Hasuko
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Hertzbach
S S
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Huffer
M E
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Huynh
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Iwasaki
M
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Jackson
D J
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Jacques
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Jaros
J A
JA
Jiang
Z Y
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Johnson
A S
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Johnson
J R
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Kajikawa
R
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Kalelkar
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Kang
H J
HJ
Kofler
R R
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Kroeger
R S
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Langston
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M
Leith
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Lia
V
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Lin
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Mancinelli
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Manly
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Mantovani
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Markiewicz
T W
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Maruyama
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McKemey
A K
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Messner
R
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Moffeit
K C
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Moore
T B
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Morii
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Muller
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Murzin
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Narita
S
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Nauenberg
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Neal
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Nesom
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Oishi
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Onoprienko
D
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Osborne
L S
LS
Panvini
R S
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Park
C H
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Peruzzi
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Piccolo
M
M
Piemontese
L
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Plano
R J
RJ
Prepost
R
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Prescott
C Y
CY
Ratcliff
B N
BN
Reidy
J
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Reinertsen
P L
PL
Rochester
L S
LS
Rowson
P C
PC
Russell
J J
JJ
Saxton
O H
OH
Schalk
T
T
Schumm
B A
BA
Schwiening
J
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Serbo
V V
VV
Shapiro
G
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Sinev
N B
NB
Snyder
J A
JA
Staengle
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Stahl
A
A
Stamer
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Steiner
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Su
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Suekane
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Sugiyama
A
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Suzuki
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Swartz
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Taylor
F E
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Thom
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Torrence
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Usher
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Va'vra
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Verdier
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Wagner
D L
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Waite
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Walston
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Weidemann
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Weiss
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Whitaker
J S
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Williams
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Willocq
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Wilson
R J
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Wisniewski
W J
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Wittlin
J L
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Woods
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Wright
T R
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Yamamoto
R K
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Yashima
J
J
Yellin
S J
SJ
Young
C C
CC
Yuta
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