HET Beginning-Trimester Report
  Third Period of 2022
August 1 - November 30

This report is primarily to give updates to PIs on recent changes/improvements and to summarize the determination of time allocations for the 22-3 trimester.



Updates on recent changes/improvements:

Updates to documentation

   Acknowledgements for the HET and for each instrument are available here:
        https://hydra.as.utexas.edu/?a=help&h=61


Updates to TSL
    A reminder that we no longer accept PMEPOCH or EQUINOX keywords in TSL. It was recently realized that our system has been tacitly ignoring anything the users submit for these quantities in  TSL files and is always hard-coding values of PMEPOCH=2000 and EQUINOX=2000. Until we are able to support other values, we will not accept these keywords in TSL Phase II files to prevent confusion and misunderstandings.


HPF returns to full-precision RV observations
    After the engineering downtime in the 22-2 trimester, HPF returns to full high-precision RV observations on August 1st.
    The HPF team has emphasized that the pre- and post-engineering work data streams should formally be treated as different RV streams, with an offset that needs to be fit.  The actual instrument shift is about 1-1.5px, or ~2.1km/s (very approximate, since it actually varies across orders).  Applying the new wavelength calibration removes the bulk of these shifts. But the PSF itself could have varied a little, so best to fit an offset explicitly for any precision applications.









Commissioning, Engineering, and Guaranteed Time allocations


The HET Board granted the following allocations for the 22-3 period:



 





Breakdown of how science hours for TACs at each partner were determined:



quantity
Apr
(hrs)
May
(hrs)
Jun
(hrs)
Jul
(hrs)
Total
(hrs)
18deg-18deg times
243.93
268.10
306.58
318.17
1136.78
Weather loss frac. 0.44
0.48
0.36
0.37

Efficiency loss frac.
(align+PRs)
0.08
0.07
0.07
0.07

"Clear science" time
125.67
129.65
182.48
186.41
624.22
Com/Eng/GTO time
 *time granted by Board




209.00
"Allowed" hours
given to TACs
for science




415.22




 

Hours allowed for each TAC as determined Jun 15, 2022:


Partner
Share
Time deficit
correction
Total hours
allowed
Allocated
as of Aug 1
(excl. Pr4)
Goettingen
0.03860
-0.45
15.58
15.6
Munich
0.05724
+5.79
29.56
15
PSU
0.24897
-6.57
96.81
95.03
UT
0.65518
+1.23
263.27*
269.7
*includes 10h removed for TESLA

Corrections were applied using 20% of the cumulative deficits in time balance between the partners. As of May 15 2022, those time deficits were:
  UT:   4.1h deficit
  PSU: 21.9h surplus
  M:    19.3h deficit
  G:     1.5h surplus
Actual time usage is carefully monitored to ensure equitable balance between the partners; these corrected allocations should help improve this balance over the long-term.

Note that TACs may allocate up to 8.3% at P0, 25% at P1, 33.3% at P2 and 33.3% at P3; P4 allocations are not restricted. Priorities of Com/Eng/GTO time are assigned by the HET Board.








SJ, 1 Aug 2022