Flight Setting Preview (in progress)

1776 med GV Tau BBP5500

leak check in hi-med, 5-pix decker

order +7 room.lab.00162.fits

order +8 room.lab.00163.fits LEAK (from 22um?)

medium mode

order 7 

1887cm-1

The filter options for 1887cm-1 included BP4990 (decker), BBP5030 (decker). The snapshots below are raw frames converted to DN/s and shown with same stretch. BBP5030 has overwhelming long wavelength leaks (10 um?).

11th order, alpha=62.08 deg, BP4990/14pix decker

11 order, alpha=62.08, BBP5030/5-pix decker

order 10, alpha=53.05, BBP5030/5-pix decker

CD19 Begins

After a couple of false starts relating to issues with the turbo pump, we started LN at 9am. Beginning pressure on the pump was 4e-5T, and the cube indicated 40mT inside the dewar, very close to
what it reads bottomed out.  Once LN started, turbo reading dropped to low 1e-7s.

As it turns out, we didn't ever have a problem with the EXES vacuum valve, though we replaced the vacuum bellows thinking there was a problem with it. Turns out the lab turbo station has something very subtle and odd going on with it.  Do not use it until we get it serviced.  For now we're using the Detector Lab's turbo on loan.

- LN started in center can at 9:35am, pressure @ turbo reads 3e-8T.

- Both tanks full @ 10:20am, turbo @1.6e-8T.

- Topped cryos, valved off dewar from pump @noon.  Base of oBox indicate 115K, detector @209K.

- Had run out by 4pm....detector and both tank sensors around 150K, so that's probably where the echelon is....

- Both tanks topped at 5:20 pm 79K, 99K, 145K  (c4, c2, detector)

- Curtis filled both tanks at 8:40pm

- Ran out overnight.  @8:30am, all temps are around 95K.  Ran LN into center can full-bore for 5 minutes to get an arbitrary partial fill...didn't want to fill entirely in car we get too much to pump out.  Temps 78K, 85K, 95K.

Filters for CD19

SDF Configuration for CD 19

Filter Wheel:
1) 18a + ZnSe (no change)

2) BBP5500 + CaF2 (no change)
3) Open (no change)
4) Reading 6.2 + MgF2 (no change)
5) N04679 + CaF2 (no change)
6) N07466 + CaF2 (no change)
7) BP6600 + CaF2    -- MgF2 blocker with BP6000

8) Soifer (no change)

9) N07053 + CaF2  -- (OCLI Q + BaF2 removed and stored) (Swapped with 4990 in decker slot 3 on 1/21/2015)

10) BP6000+ MgF2  -- (OCLI O removed and stored+ CaF2 paired with #7)

11) N07904 + CaF2 (no change)

12) BP14100 (no change)

Decker Wheel:

1) BBP8000 + BaF2 (no change)

2) BBP4700 + MgF2 (no change) (note: swapped this blocker with the mystery blocker from the 5030 on 1/21/15)

3) BP4990 + MgF2 -- N07053+CaF2 moved to FW (Swapped with 7053 in filter slot 9 on 1/21/2015)

4) BBP5030 + blocker(?) (broken blocker 1/21/15, assembled without blocker)

High-low, 5.5 um at negative and positive angles

The purpose of these tests was to find which echelle orders work best for observing 5.5 um 

(1818cm-1) with largest feasible wavelength coverage. 

order angle  90%flux    largest dash

-4 -21.082 deg   7.2 adu/sec   5pix, not 7 pix

-3 -16.020 deg   22.3adu/sec 5pix blurs on blue side // doesn't work

-2 -11.073 deg  did not check

-1 -6.198 deg    did not check

 1 3.483 deg     did not check

 2 8.358 deg     67.3adu/sec 5pix blurs everywhere

 3 13.305 deg   52.0adu/sec 5pix blurs everywhere

 4 18.367 deg   31.8adu/sec 5pix

 5 23.596 deg   11.8adu/sec 7pix

the "90% flux" 

all images are taken with same OTPAT, with Fowler 7 signal, and divided by exposure time.

to get 90%, i sort the entire array, and take the mean around 2000 pixels nearest to the 0.90*(1024^2) of the flux order pixels. This is responsive to the continuum levels in the orders. 

Snapshots of the settings:

1818cm-1, -4th order, 5-pix decker. Stretch: 0-50.

1818cm-1, -3rd, 5-pix decker, Stretch: 0-50.

1818cm-1, +2nd order, 5-pix decker. Stretch: 0:150

1818cm-1, +3rd order, 5-pix decker. Stretch: 0:150

1818cm-1, 4th order, 5-pix decker, Stretch: 0:100

1818cm-1, 5th order, 7-pix decker, Stretch: 0-100

Watching EXES Warm up

CD018 finished over the weekend. Last LN2 fill was Friday, 11/29. Last LHe fill was Saturday, 11/30. From Sunday to Tuesday we've been on turbo pump.

Now we're running dry N2 into the LHe fill tube, recording the temperature rise of the C4 (LHe plate) sensor.  

Events to look out for --

63K triple pt of N2

77K boiling pt of N2. Outgassing from getters?

log of temperatures during this warm up is kept here:

https://www.dropbox.com/s/5efk83sbckvpb7r/exes_warmup_cd018.dat?dl=0

At no point did the cube sensor pressure go above -0.04torr/ 0.00torr (flickered in between).

Plot of data so far looks like :

We think the N2 that we flowed into the neck froze in the He dewar. The first plateau from 70-240 minutes is probably due to the heat going into melting and boiling the frozen N2.
The second plateau after 300 minutes is probably due to running out of pressure from the LN2 storage dewar.


4 days sparse logging of temperatures. The Dropbox log file has notes on changes made to our procedure (heating the airflow with hot water bath/ electric heated, etc).