Convenient Scripts for Standard Fields

At the telescope computers, there is a set of useful scripts kindly provided by Douglas Tucker which allows to:

  • pick up standard fields available right now (or at any date/time), avoiding fields closer than 15 degrees from the Moon.
  • create an observation script in .json format for the desired filters. For the non-SDSS fields, the scripts autmatically offsets the coordinates so the field will lie on chip N4.

To run the scripts from the computers at the control room (observer1 or observer2):

> source ~/dtucker/bin/setup_StdStarFieldPicker.csh

The script to choose an observable standard field (decamStdFieldTimeDate.py) may get invoked in this way:

decamStdFieldsTimeDate.py --help (for detailed help)
decamStdFieldsTimeDate.py --UT=now (for standard stars accessible right now)
decamStdFieldsTimeDate.py --UT='2013/01/07 00:43' (for standard stars accessible at 00:43UT on Jan 7, 2013)

Output example:

> decamStdFieldsTimeDate.py --UT=now

Timestamp and Moon Information:
MJD: 56699.26513
UT: 2014/2/11 06:21:47
LST: 11:03:29
Moon: RA=06:46:28.821 DEC=+18:43:16.633 Phase=0.88 Up=Yes

SDSS Stripe82/Stripe10 and Other High-Priority Fields:
======================================================
Telescope Coordinates Recommended Exposure Times (sec)
fieldname RA(2000) DEC(2000) u g r i z Y MoonSep(Deg) HA ZD(Deg) Airmass
--------- -------- --------- -------- -------- -------- -------- -------- -------- ------------ --------- ------ ---------------
SDSSJ1048-0000 10:48:00 +00:00:00 30.00 15.00 15.00 15.00 15.00 20.00 62.29 00:14:44 30.28 1.16 (low)
SDSSJ0958-0010 09:58:00 -00:10:00 30.00 15.00 15.00 15.00 15.00 20.00 50.84 01:04:44 33.65 1.20 (low)
SDSSJ1227-0000 12:27:00 +00:00:00 30.00 15.00 15.00 15.00 15.00 20.00 85.59 -01:24:14 36.13 1.24 (low)
SDSSJ0933-0005 09:33:00 -00:05:00 30.00 15.00 15.00 15.00 15.00 20.00 45.17 01:29:44 36.82 1.25 (low)
SDSSJ0843-0000 08:43:00 +00:00:00 30.00 15.00 15.00 15.00 15.00 20.00 34.36 02:19:44 44.81 1.41 (medium)
SDSSJ1442-0005 14:42:00 -00:05:00 30.00 15.00 15.00 15.00 15.00 20.00 117.44 -03:39:14 60.00 1.99 (high)

Lower-Priority Fields:
======================
Telescope Coordinates Recommended Exposure Times (sec)
fieldname RA(2000) DEC(2000) u g r i z Y MoonSep(Deg) HA ZD(Deg) Airmass
--------- -------- --------- -------- -------- -------- -------- -------- -------- ------------ --------- ------ ---------------
E5-A 12:04:11 -45:24:03 10.00 3.00 3.00 3.00 3.00 5.00 96.27 -01:01:27 19.46 1.06 (low)
E4-A 09:23:44 -45:21:02 10.00 3.00 3.00 3.00 3.00 5.00 73.46 01:39:11 24.65 1.10 (low)
E6-A 14:45:33 -45:15:34 10.00 3.00 3.00 3.00 3.00 5.00 124.14 -03:43:00 45.60 1.43 (medium)
E3-A 06:42:54 -45:05:06 10.00 3.00 3.00 3.00 3.00 5.00 63.83 04:20:09 52.14 1.63 (medium)

To create .json scripts for standard fields use:

decamStdFieldsPickOneByName.py --help (for detailed help)
decamStdFieldsPickOneByName.py -v --stdFieldName="E6-A" --filterList="g,r,i" --outputFile=./std_E6-A_gri.json (for a .json file containing the exposure script for standardfield E6-A for filters g,r,i)

The README file contains the full list of the scripts in the StdStarPicker.

An additional tool to find standard fields at a given time is available within Kent's Tools. To acess Kent's Toold type observein a terminal in observer2. Then, type standards.This will give a list of 3 standard fields available at that moment (at low, medium and high airmass). You can also type standards UT (ex. standards 4:00).