Keck Starlists

Background
Formatting Rules for Keck Target Lists
Installing Your Starlist
Sample Starlist Entries

Background

Your starlist file contains the list of targets you plan to observe during the night at Keck. The file must conform to certain formatting rules described below in order for the telescope control software to read the file properly. There are additional requirements for Adaptive Optics target lists.

Note: There is NO NEED to double check that you have followed all these rules if you use our recommended Starlist Tool, which can be accessed via your Keck Observer page. Still these guidelines can be useful to verify that your starlist meets the requirement.

Formatting Rules for Keck Target Lists

Starlist Pattern

      123456789012345 HH MM SS.SS +DD MM SS.SS 2000 keyword1=value1 keyword2=value2

General Rules

One object per line.
Blank lines and comment lines are allowed for non-AO lists.
Comment lines begin with # in column 1.
All fields are separated by spaces (not tabs), except for Target Name (see below).
All keyword=value fields may be in any order.

Required Fields

Target Name: Columns 1-16 (tabs and spaces allowed)
RA: HH MM SS.SS (begins in column 17 or after, no colons ":", arbitrary number of decimal places)
Dec: -DD MM SS.SS (plus sign "+" is implied, but allowed; arbitrary number of decimal places; Note: if the Dec is between 0 and -1, the DD field MUST be -00)
Equinox: YYYY.YY or APP (arbitrary number of decimal places, <=1950 is FK4, 2000 is FK5, and APP is apparent)

Additional AO Required Fields

AO Mode

lgs=1 for laser targets
lgs=0 for non-laser targets
Tip/tilt objects must follow on line(s) immediately after targets

TT Ref Magnitude

rmag=mm.m or vmag=mm.m

TT Ref Color

b-v=m.m or b-r=m.m

Optional Fields

The following fields are identified by the form keyword=value.

Important Note: no spaces are allowed around either side of the equals sign, nor within the keywords or values themselves.

Property Keyword Units or Values AO Lists

Comments # none X

RA proper motion pmra=s.ssss seconds-of-time/year X

Dec proper motion pmdec=a.aaa arcsec/year X

RA differential tracking rate dra=s.ssss arcsec/hr divided by 15 (positive implies moving east) O

Dec differential tracking rate ddec=a.aaa arcsec/hr O

Magnitude
V and/or R vmag=m.m
rmag=m.m mag R

Color
B-V and/or B-R b-v=m.m
b-r=m.m mag R

Rotator mode rotmode=nnn pa, vertical, or stationary I

Rotator position angle rotdest=mmm.mm degrees I

Telescope azimuth wrap wrap=xxx shortest, south, or north (south is clockwise with az increasing and north is counterclockwise with az decreasing) I

RA telescope offset from target RA raoffset=xx.x arcseconds (positive implies moving east) I

Dec telescope offset from target Dec decoffset=xx.x arcseconds (positive implies moving north) I

Notes:

AO Lists key:
- R = required
- O = optional
- X = not allowed
- I = ignored
raoffset and decoffset are passive in that the y fill in the fields on the OA offset GUI, but the OA must still execute the command for the telescope to move.
For historic reasons, if the equinox is APP, either dra/ddec or pmra/pmdec will be interpreted as differential tracking rates.
You may place other comments or notes at the end of the line. These will be ignored by the control software, but retained in your text file for your information.

Additional AO Notes

Duplicate target names are not allowed in AO lists
Laser target lists are due to Keck a minimum of 3 days prior to observing. Laser target lists are submitted via the AO Guide Star Tool
For laser target lists, there is a maximum of 378 laser targets per night. For half nights, each program is allotted 64 laser targets.
For targets that are their own tip/tilt reference object ("on-axis" targets) and rates are less than 60 arcsec per hour, differential rates (dra/ttdra and ddec/ttddec) are not needed.
If the tip/tilt reference is an extended object, the AO system needs to be configured differently. This is accomplished by:
- alerting your OA before taking science images
  OR
- including the exact name of the science object in the target name field, followed by a space. For example, Uranus or Titan 16UT. The objects automatically supported by the AO operating software are Uranus, Neptune, Titan, Io and AGN (where the guide star is assumed to be 1.0'' across).
  
  Target name Uranus Neptune AGN Titan Io
  
  Extent (FWHM in arcsec) 2.80 1.68 1.0 0.7 0.7
  
  Notes:
  - The actual extent of the planetary object is larger than the FWHM
  - The AGN was arbitrarily designated to be 1.0 arcsec so that an option for an object larger than Titan but smaller than Neptune is available.
  - Be careful NOT to include the name of one of the planetary objects in the target name field for an object other than the planetary object (e.g., do NOT use Uranus PSF star as a target name).

Installing Your Starlist

In order for the Observing Assistant to locate your starlist file, you must install it in the “starlist directory” on our network. You can access the starlist directory /kroot/starlists from most of our computers.

Inside the Keck network

The convention we suggest is to store your starlist in a subdirectory which is named using the last name of the observing program's PI (e.g., copernicus). If needed, you can create the directory using the command

mkdir -p /kroot/starlists/piname

and then install your starlist using the command

cp starlist /kroot/starlists/piname

You are free to name your starlist file whatever you want.

Outside the Keck network

Login to your Keck Observer page and use the target list management tool to upload your target list to the Keck computers. In this case the starlist will be installed in the directory /kroot/starlists/web/your_keck_user_name.

Sample Starlist Entries

# basic objects including only required fields
197+17.1        07 29 09.40 +20 54 45.90 2000.0
ring neb        18 53 36.00 +33 02 00.00 2000.0

# star with proper motion
SAO 102961      17 34 24.13 +11 52 28.29 1950.0 pmra=+0.0001 pmdec=-0.007 vmag=9.0

# non-sideral targets
Hale-Bopp 5hr   17 30 6.62  -4 41 58.4   APP dra=0.35  ddec=7.3
Titan   6:00UT          01 05 39.60 +04 00 28.846 APP dra=-0.96 ddec=-4.2

# slitmask with specified rotator position
Cl0024+16-fld 1 00 24 00.00 +16 00 00.00 2000.0 rotdest=123.45 rotmode=pa

# target observed at parallactic angle
Herschel101     12 34 56.78 +01 23 45.67 2000.0 rotdest=0.0 rotmode=vertical

# science target with nearby offset stars
198xq            13 55 45.78  -25 24 03.3  2000.0
198xq_S1         13 55 46.85  -25 23 46.3  2000.0 raoffset=-14.51 decoffset=-16.99   # 14.51" W,  16.99" S to 198xq
198xq_S2         13 55 48.26  -25 22 10.6  2000.0 raoffset=-33.61 decoffset=-112.72  # 33.61" W, 112.72" S to 198xq
198xq_S3         13 55 39.96  -25 21 50.1  2000.0 raoffset=78.83 decoffset=-133.21  # 78.83" E, 133.21" S to 198xq

# AO targets
300 Sag A*      17 42 29.330 -28 59 18.50 1950.0 lgs=1
   0609-0602733 17 45 40.713 -29 00 11.18 2000.0 rmag=14.0 sep=19.3 b-v=0.83 b-r=1.65 S=0.31
   0609-0602749 17 45 42.287 -29 00 36.80 2000.0 rmag=13.5 sep=31.2 b-v=0.68 b-r=1.40 S=0.30
SKY Sag A*      19 00 00.0   -30 00 00.00 1950.0 lgs=0 comment=no laser
M5_core         15 18 33.240 +02 05  1.40 2000.0 rmag=11.5 lgs=1 comment=NGS/LGS?
IRAS 16342      16 37 39.890 -38 20 17.40 2000.0 lgs=1
   0516-0460239 16 37 39.178 -38 20 13.33 2000.0 rmag=14.3 sep=9.3 b-v=1.01 b-r=1.88 S=0.35
313 V1974 Cyg   20 30 31.700 +52 37 51.30 2000.0 lgs=1
   1426-0416488 20 30 28.917 +52 37 12.99 2000.0 rmag=13.7 sep=45.9 b-v=1.65 b-r=2.45 pa=69.0 S=0.27
NIR standard    21 30 31.700 +12 37 51.30 2000.0 vmag=10.1 lgs=0 comment=Ellias