Measurement of the proton asymmetry parameter in neutron beta decay.
The proton asymmetry parameter C in neutron decay describes the angular correlation between neutron spin and proton momentum. In this Letter, the first measurement of this quantity is presented. The result C= -0.2377(26) agrees with the standard model expectation. The coefficient C provides an additional parameter for new and improved standard model tests.
Physikalisches Institut der Universität Heidelberg, Philosophenweg 12, 69120 Heidelberg, Germany. marc.schumann@gmx.net
M
M
Schumann
M
M
Kreuz
M
M
Deissenroth
F
F
Glück
J
J
Krempel
B
B
Märkisch
D
D
Mund
A
A
Petoukhov
T
T
Soldner
H
H
Abele