Hi Colin and Jon,
Thank you for both of your reports from Pole.
Make sure that the B2 RPS measurement is proceeding
well. Switch to
far sidelobe
mapping once that is done (probably not today).
I hope we will hear from you shortly on the B2 telecon, but in case the
satellite does not cooperate could you send a quick summary of BICEP2's
plan and projected schedule for the coming week?
Are we ready to make a decision about removing the FFFlat?
Have you got clear instructions on sidelobe mapping?
How about plan for taking BICEP2 off the mount--are the cryostat loader
parts and procedures clear? Or do you need to review details with folks
up north?
thanks,
John
On 11/26/12 2:43 PM, Colin Bischoff wrote:
hi all,
We got a lot done over the weekend, since the last update.
[Saturday]
* Took down the far field flat.
* Moved the RPS from DSL to MAPO and got it working on the bench.
[Sunday]
* Removed back end electronics from rx3, rx4.
* Installed RPS on the MAPO mast, adjusted attenuators, and leveled
the source so that BICEP2 can start its RPS schedule.
[Monday]
* Took down rx3 and rx4 in the morning.
* Started opening up rx3/K4 and rx4/K5:
- rx4/K5 insert has been removed and the telescope and camera are
separated.
- rx3/K4 is almost ready to remove the insert
* We found a couple of suspects for the rx3 cryogenic problems --
There was a light leak from an open hole that was not taped over near
the interface between the 50K tube and the filter stack. The much
larger problem is that the tunnel around the 4K strap had a massive
hole and seemed to be made primarily from Al tape, not mylar. We took
some photos, which I will try to send along later.
* Having some new computer issues with the BICEP2 RPS observation.
I've been in touch with Walt about this. However, I'm cautiously
optimistic that we might have solved the problem by switching to a
different USB port on the RPS laptop.
[Plan for today]
* Sarah arrives!
* Get the FPUs out of rx3 and rx4. This will give us a full day for
Grant and Howard to remove a tile, as specified in Grant's recent
email and responses.
* Still trying to track down the FTS, which we think arrived at Pole
on Friday. Zak or Jon have the best information about this, so maybe
they can provide an update.
* Deal with sudden increase in lab clutter caused by opening up two
cryostats at once.
* Make sure that the B2 RPS measurement is proceeding well. Switch to
far sidelobe mapping once that is done (probably not today).
-colin
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