Summary: Too much cloud to do anything scientific (in fact, the dome was closed from 4:50 to 8:20). The night was however useful to practice various LUCIFER observing procedures. We probably didn't get any scientifically useful data during this two-night LUCIFER run, but we have at least learned a lot about the procedure for LUCIFER MOS observations and its pitfalls. We were also able to confirm that the three programs (A. Zabludoff's, G. Riekes', and E. Egami's) would work as designed. We would be happy to share our experience with other AZ observers so that they will be better prepared for future observations. We would also like to thank Dave Thompson (especially!), Olga Kuhn, Ian McGreer, and Fuyan Bian for their help during this run. A few points to note:
  • Potential problem with the mask position repeatability - It seems that we see a slight offset (2-3 pixels with the N3.75 camera) every time our slitmask gets moved into the focal plane. If this is really the case, we might want to look into the possibility of physically cutting alignment holes on slitmasks and use them for the final mask alignment.
  • Interrupting guiding and taking calibration frames - To keep telescope pointing while taking calibration frames (e.g., when inserting arc integrations among science ones), the TCS must be put into the track mode, which can be done by the telescope operator. However, to resume the active mode after taking calibration frames, the TEL-MODE=ACTIVE instruction has to be sent from the Telescope Control GUI of the Lucifer observer. What is tricky is that sending this TEL-MODE=ACTIVE instruction will also send the coordinates in the Next Target and Next Guide Star fields (see the notes by I. McGreer), which are not likely to be correct values and could slew the telescope to a completely different position. Therefore, when doing this, make sure to copy the coordinates in the Current Target and Current Guide Star fields into the Next Target and Next Guide Star fields.


  • Taking arcs and flats for Egami's program.
2:00
  • Opening the dome around the sunset as usual, but there are a lot of clouds in the sky.
2:00-4:00
  • Too much cloud to do any science, so practiced the procedure to perform telluric standard star observations with a MOS slitmask (following the script sent from MPE). A telluric standard was placed at two slitlets at the opposite ends of a slitmask (along the dispersion direction) using the SHIFT IMAGE task. Since everything had to be done in the tracking mode without guiding (clouds were too thick to see the guide star), it was a bit time-consuming to perform all the required offsets, but with a little more experience, it should be straightforward to do this under a better condition.
4:00
  • Too much cloud to do anything. Sitting and waiting....
4:40
  • Saw a bit of clearance, so started mask alignment procedure for Egami's program.
    Started science integrations, but the guide star started to fade quickly.
    Lost the guide star in the middle of the second 10min integration. The data are probably useless...
4:50
  • Clouds becoming thicker. Closed the dome...

8:20
  • Started the target acquisition script for A. Zabludoff's program.
    Aligned the slitmask.
9:00
  • Putting the telescope into the track mode; taking arcs.
    Sending the TEL-MODE=Active instruction also sent wrong Next Target and Next Guide Star coordinates to the telescope (these fields wouldn't be updated by running the target acquisition script, and would not reflect the Current Target and Current Guide Star coordinates). This has sent the telescope to the pointing star used previously frown, sad smile .
    While trying to recover from this, the Telescope Control GUI froze. Logged out and restarted the Lucifer control software.
9:30
  • Back to Page 1. Starting the target acquisition.
    Aligned the slitmask. Saw a few bright reference sources in the slitlets.
9:45
  • Started Zabuldoff's science integration. Guide star faint, suggesting a cloud cover.
10:00
  • Lost the guide star due to thickening clouds. Stopped integration.
10:15
  • Switching to G. Rieke's program. Target acquisition; Alignment with the 1" long-list mask.
11:15
  • Starting science integrations for Rieke's program, but looking through a lot of clouds. Barely guiding...
    Observing a telluric standard at the end.
12:00
  • Dome closed.
    Taking flats, arcs, and darks for Rieke's and Zabludoff's programs.

-- EiichiEgami - 18 Apr 2010
Topic revision: r2 - 18 Apr 2010, XiaohuiFan
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