Beam positions were centered on target last night before starting optics, but we see scrapping again (due to 5 MeV beam energy change this morning? halog 377086). BPMs have lock on it. Pengjia tried changing y-position but the beam is hitting both up and down, so he reduced the slow raster size to about 1.5cm but still beam positions are not optimal. Beam is scrapping the beam pipe somewhere and we see 10 times higher rates in 3rd arm.
We are running like this since we believe HRS do not see this beam scrapping. Is it possible to fine tune the beam again?