Tech time tasks for NOTCam

Comments to Amanda


JHKs zeropoint monitoring (WF)

On every NOTCam technical night which is clear/photometric, observe one of the below suggested standard fields at three different air masses in the range [1,2]. NOTCam imaging is done with the WF camera and the three filters JHKs. The instrument is setup correctly from the scripts, and target is acquired. You have to verify that autoguiding is achieved, and the rest is automatic. A finding chart should pop up on the screen, but no pointing adjustment should be needed in normal cases. The standard fields are found in the TCS catalogue /catalogue/notcamstd.cat but you don't need to load it, since the script will add and goto target.

Use the sequencer scripts whose names are given in the table. The scripts make a 5-point (dice) dither for each of the three filters Ks, J, and H, and adjusts the telescope focus accordingly per filter. The total time refers to the total time spent doing all three filters.

Field FS Other name RA(J2000) Dec(J2000) K-mag # stars expmode script Tot time
AS05 6 Feige 22 02 30 17.5 05 16 25 13.4-13.5 2 frames 3.6 5 notcam.as05-jhk 11 min
AS16 14 Rub 149 07 24 15.4 -00 32 49 11.0-14.3 5 frames 3.6 3 notcam.as16-jhk 10 min
AS19 17 M67-IV-27 08 51 20.2 11 52 43 9.7-12.4 3 expose 4 notcam.as19-jhk 9 min
AS26 23 M3-VZ193 13 41 45.4 28 29 50 11.4-12.4 2 frames 3.6 3 notcam.as26-jhk 10 min
AS33 35 . 18 27 13.6 04 03 10 11.7-13.2 3 frames 3.6 3 notcam.as33-jhk 10 min
Ser-std 143 Ser-EC68,EC84 18 29 51.2 01 11 48 11-12.9 2 frames 3.6 5 notcam.serstd-jhk 12 min
AS40 . NGC 7790 23 58 50.2 61 10 02 9.4-10.8 6 expose 4 notcam.as40-jhk 9 min


The designation FS stands for the UKIRT Faint Standards (see Leggett et al. 2006, MNRAS 373, 781-792 for references and JHK magnitudes.) Finding charts are obtained by clicking on the field name in the table. These K-band charts have North up and East left, the FOV is about 4' x 4', and they are taken from Hunt et al., 1998, AJ 115, 2594, except for Ser-EC68,EC84 which is a NOTCam image.

The field Ser-std contains the new red standards EC68 and EC84 (see Leggett et al. 2006, MNRAS 373, 781-792 with J-K colours from 3.57 to 3.99 magnitudes.


The visibility plot of today:


Minimum observing altitude when lower hatch closed: 35 degrees.

Please wait ... Generating visibility plot

 


To calculate the visibility plot for any date you can cut and paste the following table into the Staralt program.
as05 02 30 17.5 +05 16 20
as16 07 24 15.4 -00 32 47
as19 08 51 20.2 +11 52 43
as26 13 41 45.4 +28 29 50
as33 18 27 13.6 +04 03 10
ser  18 29 55.4 +01 13 11
as40 23 58 50.2 +61 10 02


Illumination correction data

A model of the illumination correction for the H-band has already been made by Joachim Janz and is published in Janz et al. 2013, submitted. We still need to take data in photometric conditions to map the J band. Do as follows:

For the Ks band we have a total of 4 + 2 + 7 + 2 = 15 scans.
For the J band we have a total of 5 + 4 + 3 = 12 scans.


Vignetting of narrow-band filters

Check vignetting of narrow-band filters because of the fact that they are mounted tilted and in the parallel beam. Find a star with a strong emission line in e.g. Brackett gamma, for instance:

X-Per RA=03:55:23 DEC=31:02:45 (J2000) V=6.1mag

and scan the star across the FOV using the Br gamma narrow band filter (#209). Use a 5x5 dither. A script is found in ~scripts/staff/amanda/ and it is called fov.script, but you may have to adjust to a shorter exposure time than the "frame 4 8".


Through-focus test

Check the calibration and performance of the focus pyramid by running the script:

notcam.through-focus exptime

where exptime is the suitable exposure time for the focus star you have selected high in the sky (with no pyramid in the beam). For a typical exptime of 10 seconds, the whole script takes about 30 minutes. Alternating images are taken with the focus pyramid in and out scanning the focus range of +-150 units around initial guess-focus. The exptime is multiplied by 4 for the images taken through the focus pyramid. Make sure the instrument setup is correct before starting. Use Ks filter. Set the tcs.focus-position to your initial guess and tcs.focus-delta to zero.


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