Privacy and Security Notice
Archived Messages for HALLA_MIN_1997@cebaf.gov: Minutes
Minutes
John LeRose (lerose@CEBAF.GOV)
Thu, 13 Feb 1997 09:21:40 -0500
Minutes of Hall A Group Meeting 11 February 1997
1 General Announcements: (Kees de Jager)
1.1 Welcome to Paul Brindza as new supervisor of
design and engineering in Hall A
1.2 Eddy Offermann will be run coordinator for the
1st two commissioning runs. Contact Eddy one
week in advance if you have any specific ideas
or requests for the runs.
1.3 Re the facility name change: anyone who wants
new business cards should contact Janet within
one week. This is a one and only one time
offer.
2 Installation: (Ed Folts)
2.1 Cryogenics: have found and repaired 2 leaks are
now cooling down (with priority to Hadron
Dipole)
2.2 Target Chamber Window:
2.2.1 Installed large window and it broke
yesterday afternoon
2.2.2 Source of failure understood
2.2.3 Nevertheless want to consider different
thicker window. Eddy will evaluate.
2.2.4 Installing old 2 port window today
2.3 Water installed on diffuser
2.4 Question re beam schedule in Hall this weekend.
2.4.1 Close noon Friday
2.4.2 Superharp tests 8 AM Saturday to 8 AM
Sunday.
2.4.2.1 Pascal Vernin reviewed plans for
these three shifts and welcomes
volunteers
2.4.2.2 Pascal reports on discussions with
Accelerator re removal of unused
magnetic elements in the arc in order
to simplify control of the remnant
field.
2.4.3 High Power tests Sunday to Monday
2.4.4 Larry Cardman insists on verification of
background monitoring. Arun will check on.
2.4.5 Prompts discussion of Accelerator desire
to leave the Hall locked up through the
week. Bottom line is that it’s out of the
question. We have too much to do in there.
2.5 Ed requests permission to test waterfall
target, by pressurizing it slightly, for leaks
resulting from the window implosion. Permission
granted.
2.6 Still trying to remove excess material from the
Hall. (e.g. Pierre’s boxes) Pierre agrees to
meet with Ed in the Hall after the meeting to
tell him what can go.
3 Magnetic Field Measuring and Monitoring: (John
LeRose)
3.1 Reports on latest schedule and plans for the
Septum magnets
3.2 Software and Hardware essentially ready for
field gradient measurements for polarized 3He
in target vicinity.
3.3 Planning to do some field stability tests on
the Hadron Dipole as soon as it is available.
4 Commissioning: (Eddy Offermann)
4.1 Energy calibration studies show that the beam
energy was 846.3 MeV for nominal 845 MeV
4.2 Repeatability studies are ongoing
4.3 Have started some preliminary background
studies. Pole tip scattering discussed. Needs
further systematic study.
4.4 Nilange reports on acceptance studies. Some
curious y0 shifts suggest need to get BPM
information into the data stream. (Shifts may
or may not be correlated to beam motion)
5 Beamline (Arun Saha)
5.1 Pierre Bertin reports that 3-D measurements are
being done at NASA on the detectors for ep.
5.2 ep will need access to Hall during April. Arun
will coordinate with Ed Folts.
6 Detectors: (Bogdan Wojtsekhowski)
6.1 Hadron Arm delay lines installed yesterday
6.2 Frame has been moved inside the hut.
6.3 Alignment group is measuring the position of
the VDC
6.4 Plan to start flushing gas in VDC tomorrow.
6.5 Thanks to an heroic effort by Maja the aerogel
Cerenkov is installed.
6.6 Expect to start taking cosmic ray data on
Friday
7 Cryotarget: (Jian-Ping Chen)
7.1 Gas system layout at top of cryo-can undergoing
final design iteration.
7.2 Finished design on service window and ports on
spool piece.
7.3 Cell blocks all plated.
7.4 Working on upstream windows. Got first 2 back
from machine shop. One leaked. Working on
improvements.
7.5 Cold test planned for this week in the Test
Lab.
7.5.1 setting up 30 sensors and low power heater
7.5.2 software and controls are ready
8 Hadron Electronics & Optics studies: (Meihua “Meme”
Liang)
8.1 Tested new configuration of MLU. It is working
now.
8.2 Working on analysis of optics study runs at 2.4
GeV
9 Controls: (Javier Gomez)
9.1 Electron and Hadron Dipole power supply
regulators have been repaired by James
Proffitt.
9.2 Repair of Q3 Hadron power supply (dumps
whenever you try to reduce the current) must
wait until magnet is cold.
9.3 Schematic for the slit box interlock is
completed.
9.4 BRU servo tested successfully (to be used on
the slit box and other things)
9.5 Valhalla DAC’s for Quadrupoles are being
tested.
9.6 Meeting yesterday re angular measurement and
positioning.
10 Ops Manual and Møller Polarimeter: (Sirish Nanda)
10.1 Sirish reminds us that the Ops manual must be
completed in one month in order for us to be
ready for the first experiment in three months.
10.1.1 e-mail message has been circulated re
outstanding contributions needed.
10.1.2 Still wants LaTex format. If you need
help translating to LaTex see Marti
Bennett.
10.1.3 Will accept HTML format as well.
10.2 Møller:
10.2.1 Had meetings last week
10.2.2 U. Ky. redoing vacuum box.
10.2.3 Ed Folts questions vacuum pump
requirements. Sirish will try to clarify.
10.2.4 Plan to test power supply in the Hall
next Thursday (20 February)
10.2.5 Dannphysik has tentatively scheduled
acceptance test for the first power supply
for week of 10 March.
-JJL