Log entry time 23:56:03 on September 30, 2010

Entry number 333274

Put the detector in position (note: the beam wasn't going through the chicane), and "played" with the HV to get rates (see attached plot): - no visible signal if HV < 1550 V; - the vanishing rates during the short beam trip shows that these counts come from the halo; - rates are below 10 Hz for HV = 1600 V, around 10 Hz for HV = 1650 v and clearly above for HV = 1675 V. Didn't dare going above yet (and mostly, it wasn't useful).

Figure 1