Difference between revisions of "Installation notes for active collimator beam test 2007"

Revision as of 11:07, 26 March 2007

Preparation notes for active collimator beam tests to take place in Spring 2007. The online accelerator schedule shows that there will be significant photon running in Hall B in 2007.

• 2-20-2007 [R. Jones] I made an initial contact with Pawel Nadel-Turonski, spokesman of g13. G13 is scheduled for running in Hall B 3/8 - 5/29. Pawel welcomes us to conduct active collimator tests in parasitic mode during this period. The beam endpoint energy will gradually increase throughout this period, starting at 3.30 GeV and ending at the top accelerator energy of 5.16 GeV.

• 3-12-2007 [F. Klein] We have a stage+motor available (horizontal motion up to 1.5m). I checked the VME motor drivers in the Hall-B forward carriage but strangely all channels are connected (although I cannot recall more than 2 motors used in the alcove). I'll find out where the cables go next weekend. For sure, I'll have epics controls running for the stage!. I was looking for a table but haven't found Tom Carstens who keeps the stuff somewhere (that's easy to solve!). I connected some cables running from the forward carriage to the Hall-B counting house (in case that we want to look at discriminator signals).

• 3-19-2007 [F. Klein] There is a EPICS stepping motor controller located on the CLAS forward carriage that supports 4 motors. Right now two of them are connected on both ends, and the other two are connected only on the controller end, and are available for the translation stage motor. A motor requires two cables for the stepping motor control and also the limit switches. Franz has these cables and will provide them. We need to move a table into the alcove (Franz thinks one is available that is about the right height). Things we still need are:
  • support wedge for active collimator
  • ethernet and power for the PC
  • schedule time to install the table and collimator
  • schedule survey crew to align the collimator

• 3-19-2007 [R. Jones] If possible, I would like to install the detector during the week of March 26. The collaboration meeting is Thursday-Saturday.

& 3-26-2007 [V. Burkert] Thanks for the detailed description of the proposed test setup in Hall B. In general, I have no objection to doing this if it doesn't interfere with the running experiment. I do see a potential that there might be something like a "red flag" in that you want to continuously run this test. Hall B has currently quick access to the Hall without having to survey the Hall for radiation due to the generally very low level of activation in the Hall and in the beamline area. If your active collimator is continously exposed to the photon beam it may develop a high enough activation that Radcon may not allow the same procedure to continue. Therefore, I suggest that you work with Radcon to make sure that we will avoid such a situation. Additional shielding of the collimator area maybe sufficient, but Radcon clearly needs to be involved in setting this up. By the way, today I was made aware that the machine maybe running through Tuesday. If that is the case then Hall B will remain closed. So, you may want to check with the counting house (x5244) what the situation is.