5 June 1996
					G. Bunce


g-2 Ring News, and the Inflector, and the Beam
----------------------------------------------

	We started cooling the g-2 ring yesterday.  We had a 3 week delay to
repair a replacement first stage heat exchanger, which was completed
yesterday.  The outer coil was at 291 K at 9 am this morning.  We have added
coil restraints (stops), going from 4 to 8.  The stops have been redesigned
with springs which work over a limited range from about 85 K down, and are
"hard" when fully powered.  The stops transmit force to the cryostat, and
the cryostat is held by pushers to the iron yoke.  We have gone from 4 to
8 pushers, and 4 also include springs to protect us from temperature change
effects in the building.  We have also put in 7 windows so we can watch the
position of the outer coil mandrel and shield as we cool and power.  We have
also gone from 4 to 8 stops on the inner coils.

	The inflector has been tested at KEK.  In January the magnet quenched
at 1750 amps at the crossover between the inner and outer coils (the 
inflector is a double cos theta magnet where the outer cosine winding cancels
the return field of the magnet, the whole thing then fitting in between the
poles of the storage ring).  That quench burned out the crossover due to
inadequate protection.  This has been repaired and the sensitivity of the
quench protection increased.  The magnet runs at 2850 amps for g-2.  In the
test over the last 2 days, the inflector quenched several times around
2000 amps.  The quenches were located in the conductor which connects the
current leads and the magnet, not in the inflector body or crossover.  The
resistance in the crossover is 2 x 10^-9 ohm, or 8 mW at 2000 A, which agrees
with the report by the company that repaired the joint. They are now warming
the system, plan to access the problem area, and expect to test again next
week. 

	We have been working on the beam from May 2.  We first established
extracted protons to the target, actually steered to miss the target.  This was
very successful.  Extraction was done by/under Sanki Tanaka.  We use the
primary beam line to RHIC, then two dipoles steer the beam to a new line which
leads to the production target, which is in a new blockhouse.  This transport
was done with calculated magnet settings only.  Charlie Pearson led the
beamline construction, and Hugh Brown designed the optics. Extensive "fault"
studies were done to test the integrity of the shielding. This was fine, scaled
to 60 x 10^12 (60 TP), the full AGS intensity which we will use.  We then
"commissioned" the target, a nickel cylinder which rotates in a bed of water,
the beam hitting along the axis at the beam left edge.  We used a boroscope to
verify that it survived the fast beam, which we tested up to 3.5 TP per bunch
for 30 minutes. 

	We are in the process of tuning and doing the necessary fault studies
(checking shielding) for the secondary beam.  We have the expected beam at
an intermediate beam dump (3 x 10^7 for 1 TP protons).  We are using a set
of profile monitors (SWICs) and ion chambers which allow us to study the
optics of the quadrupole channel very elegantly.  The instrumentation works
very well.  The AGS instrumentation group has done an excellent job!  We are
using a CAMAC readout set up by Joel Kindem of Minnesota which allows us to
study one pulse at a time.  This has several advantages:  we don't irradiate
the target area unnecessarily, we are very parasitic, and we can see the
beam pattern in all the SWICS and ion chambers for the same pulse.

	We still need to do the fault studies for the secondary line--
probably Thursday night--then bring the beam to the ring.  The detector group
has 4 detectors (calorimeters and hodoscopes) in the ring awaiting beam.