Target Cooldown.  Takes ~4 hours. Can only be done once magnets are
cold in all halls. Vacuum needs to be in the 10^-5 range or better.
Have handy (ahead of time) the official procedures at
http://opsntsrv.acc.jlab.org/ops_docs/MCC_web_interface/interface_pages/operating_procedures.asp

0) Verify target rotation & lifting are ok. Is the archiver running?
   (on jeffylab, in ~/Archives, ./start_archiver).

1) Call mcc and tell them you want to cool down the target. They need
~1h to get ready. Sometimes they forget about you, so a reminder may
become necessary. Make sure the cooldown valve AND the precool jtv are
open. That is, open warm return valve (=cooldown valve EV9177; 10 is
wide open). Open precool HX valve EV9125 too, otherwise you may not
see TD9178 drop as it is supposed to.

2) Open up ballast tanks. Check valve lineup if anything has changed.
Check the following valves:
open: MV9127, 9126, 9113, 9148, 9130, 9120, 9116. MV9114 was closed.
open: MV9109, 9149, 9107, 9131, 9133. MV9108 was closed.

3) In area, power up itcs, heater ps (the power 10s), jt controllers,
and plug in all 3 fan controllers.

4) When mcc calls back, open loop JTs to ~5%, keep flow ~< 5g/s (Seely
says 8-9 g/s ok) during cooldown.  Keep an eye also on esr temp, if it
goes much above 15.5 degrees, throttle back.  When the itcs come on scale
(ie below 99K) turn on the fans to 30 Hz. Do not cool D2 too fast or
you might form D2 ice in the heat exchanger. Make sure the  solonoid
valves SV9082 (from loop1 gaspanel) and SV9012 (from loop2  gaspanel)
are open. These open the fill lines to the target from the gas
bottle/ballast tank. It should take a couple hours to drop down to the
vapor pressure curve. Then go to 8-9 g/s  flow.

5) Follow mcc procedure as outlined in white notebook in counting room.

6) When TD9178  drops below 25 K (28K works better),  call Mcc and
inform them we want to go to cold return. Inform the other halls too
since this will cause an excursion in the esr. Close warm return valve
& precool valve. But close the precool valve first, over a few
minutes.  Then wait 5 minutes before starting to close the cooldown
valve.  To close  cooldown valve, first go to 50% for a couple
minutes, then slowly close the rest of the way over a couple more
minutes. This will cause a blip in the esr over 1/2h, watch out.

Note: We are experimenting with closing this valve more slowly; 
doing it in small steps over 20-30 minutes seems to mitigate the ESR
excursion.

Note: Ongoing problem that sometimes, the target IOC dies while moving the warm
return valve. When this happens it keeps going in the direction you
were moving. This will crash the esr. Patch: Never use the gui to move
the warm return valve. Do it in the hall. Unplug the multiconnector
cable labelled "P3" just to the right of the keyboard. Then move the
warm return manually with the buttons behind the gas panel. Then
replug in "P3". Immediately re-open the H2 and D2 fill solenoid
valves, because they automatically close when you pull the P3
cable. Left closed, the pressure will fall sub-atmospheric during a
cooldown.These fill solenoid guis can be opened from the Loop1 and
Loop2 guis. Note this operation must be done multiple times since the
warm return valve has to be closed slowly.     


7) Make sure heaters come on when goal temps are achieved.  Watch for
blips in esr from hall A cooldown.