User name Saha
Log entry time 11:45:27 on December 4,1999
Entry number 30578
keyword=Hall A Beam Checks for e89044
Systems Check for Hall A by Hall A personnel
In every shift Hall A personnel should pay attention to the following parameters:
1. Fast Feedback operational for Hall A
Make sure that it is running in both position and energy mode for Hall A.
If there is any doubt, verify from MCC.
DO NOT accept acceptable beam unless this is operational.
You will be responsible if it is not on and you accept beam.
2. OTR screen for beam energy width
Monitor the OTR screen
It is in the Accelerator Monticello MEDM screen in under Data Acq. Click on Dataqube Control Panel. In this screen, the source should be set for Hall A (If not, request MCC to put source to Hall A and set the proper standard settings for Hall A - John Lerose knows what they are for Hall A, MCC should also have them). If the settings are right, you should get narrow beam profiles for x and y profiles. If the screen is calibrated, the important parameter to monitor is the Calibrated x width.
This number reflects the energy width of the beam.
The OTR is located at the 1C12 location of the Hall A arc which, in achromatic tune, is the point of high dispersion in the arc : Dispersion = 4 m
For a width of 0.200 mm, reflects a energy width of 5 x 10^[-5].
This is the acceptable limit for our experiment (e89044).
If the width is significantly more than 0.200 mm, inform MCC and see if it is just a bad calibration or setup. If the width is really > 0.2 mm, MCC needs to make it smaller.
3. Perform Harp scans of scanners (#5,6) before the target
Performed this regularly to verify both beam position as well as width of the beam.
Also monitor beam size with "Spot" and see if it is calibrated with harps.
Instructions to run Harp scans are in the Experimental web page.
4. Monitor the beam related Strip Charts on the Accelerator screen.
Make sure all the parameters are within acceptable limits.
- Beam position on target (on BPMs 1H03A and B) are within 0.250 mm.
- Check both Hall A BCMs are functional and calibrated (proper coefficients) on BCM screen. If either one or both are frozen or non-functional, hallasc5 ioc may need to be rebooted.
- Beam energy widths are within 5 x 10^[-5] (see note 2 for OTR screen)
- Beam energy has not changed, more importantly the MBS1YC Bdl value has not changed. Inform MCC if this has changed and also me (Saha).