  Beam-line equipment was upgraded for experiment E08-027 (g2p) in Hall A at
Jefferson Lab. Two beam position monitors (BPMs) were necessary to measure the
beam position and angle at the target. A new BPM receiver was designed and
built to handle the low beam currents (50-100 nA) used for this experiment. Two
new super-harps were installed for calibrating the BPMs. In addition to the
existing fast raster system, a slow raster system was installed. Before and
during the experiment, these new devices were tested and debugged, and their
performance was also evaluated. In order to achieve the required accuracy (1-2
mm in position and 1-2 mrad in angle at the target location), the data of the
BPMs and harps were carefully analyzed, as well as reconstructing the beam
position and angle event by event at the target location. The calculated beam
position will be used in the data analysis to accurately determine the
kinematics for each event.
