PHOBOS at RHIC 2001

Vertex Distributions

•Beam Orbit can be calculated for each fill, it was found to be very stable

•For the 130 AGeV data

¨X = -.17 cm, sX = .17 cm

¨Y = .14 cm, sY = .08 cm

•Make a cut in Z to define a fiducial volume:

3 mm in transverse direction