| The first measurement of the proton weak magnetic form factor GZM has been made using parity-violating, elastic H1e&ar; ,e scattering at a momentum transfer of Q2 = 0.1 GeV2/c2). A measured physics asymmetry of Aphys=- 5.22+/-2.24+/-0.62 x10-6 corresponds to a measured weak magnetic form factor of GZMQ2=0.1G eV2/c2=0.298+/- 0.156+/-0.044+/-0.024 mN. The first uncertainty is statistical, the second is systematic contributions from the measurement and the third uncertainty is the contribution from the uncertainty in theoretical calculations of weak radiative corrections. The strange quark contribution to the proton magnetic form factor GsM has been determined from the weak magnetic form factor. After applying model dependent radiative corrections, the value determined is GsMQ2=0.1G eV2/c2=0.49+/- 0.62+/-0.17+/-0.10m N. The measured value of GsM does not differentiate from zero. It is anticipated that the planned supplemental increase in the data set will decrease the uncertainty by a factor of two and improve the experimental precision of GsM . |
