Xcov 22 Observing Instructions: PG 1456+103

Coordinates:

      RA  (2000)    14 58 32.7 
      Dec (2000)   +10 08 18   
      Magnitude	    15.9

Consult the finder charts for more information.

Control Center:

The XCOV 22 control center is at Iowa State University's Department of Physics & Astronomy. The Control Center will contact each site at the beginning of the night for a time check and site update. Consult the Phone Contact List for information on phone, fax, and email for the control center as well as the other sites for this run.

Time Check:

Please do a clock time check each night before taking data and verify your time with HQ at the beginning of the run, and as often during the run as possible. HQ will have an accurate clock available for phone clock checks.

Run start:

Please start your run on an integral multiple of ten seconds (times ending in "0"). Check the computer clock just before the start of a run, synchronizing with your master clock to within 0.1 sec if possible.

PMT observers

Integration times: Use 10 second integration times.

Filters: Use NO filters in any channel.

Guide Stars: Please consult the finder chart. PG 1456 has several stars of comparable brightness in the field. Record your ch2 offsets and telescope plate scale so we can determine exactly which star was observed.

Sky calibration: Observers with 3-channel photometers should record sky in all three channels near the beginning and the end of each run to permit accurate cross calibration. Observers with 2 channel photometers should take sky by moving the telescope. We have sometimes in the past used the channel 2 verniers to measure channel 2 sky (only) but we find this is not really reliable. Try to take sky as often as needed, at least once per 1/2 hour, for 4 or 5 good sky points; more are not needed and cause unwanted data gaps in the light curve of the target star.

Apertures: Please use the smallest aperture consistent with getting data of good quality (e.g. no visible loss of light to the edge of the aperture). A general rule of thumb is to use an aperture approximately 8-10 times the diameter of the seeing disk. Record the size of the aperture (in arcsec) in your observing log.

CCD observers

Integration times: It is recommended that the separation between consecutive frames is either 10, 15 or 30 seconds, which will make data merging easiest. Observers should use their judgement to obtain the appropriate balance between signal to noise, cycle time, and duty time.

Filters: Use NO filters.

Choosing the CCD field of view: Please consult the finder chart. If you have the possibility to window your CCD frame to decrease the readout time, please do so by keeping the variable and at least two comparison stars of about the same brightness as the variable on your frames.

Calibrations for CCDs: Please make sure to collect a sufficient number of bias and dark frames as well as flat fields for each night (whenever possible). We leave it to you if you prefer to take sky or dome flats.

Observing Logs:

We ask that you keep an accurate log of the night, including observers, apertures, integration time, etc., and send a copy of your observation log along with the data.

Data Transfer:

We will be reducing the data as fast as they come in, and we'll contact you promptly if we have any questions about, or problems with, the data you send. There are two ways to send your data and logs at the end of each night.

1. By FTP to: wet.physics.iastate.edu
   (Note that this has changed from the previous site of wet.physics.iastate.edu!)
   The username for the FTP site and the password is available through email. This information is only available through email because we have had problems with hackers filling the FTP system in the past. This is not an anonymous FTP transfer, so you will need the username and password to upload your data. If you use the FTP option, load your data into the "wet/incoming/xcov22/" directory.
   
   
2. Via e-mail to: wet.physics.iastate.edu
   

Data transfer (CCD observers):

WET HQ is not set up to handle the large volume of image data that CCD systems produce. If you have on-line frame extraction and/or data reduction capability, we would appreciate to receive these preliminary results at your earliest occasion as well, so we can include it in the planned real-time analysis. You can transfer these (small) files as above.

Final analysis:

CCD observers, we would appreciate if you could do the basic reductions (overscan, bias, dark count, flat field corrections) yourself and send us the raw and reduced science frames after the run, along with an explanation of your reduction procedure. If you can't do this, please send us all your raw frames. We ask you to mail DAT tapes or CDs containing FITS files to: Gerald Handler Institut fuer Astronomie Tuerkenschanzstrasse 17 A-1180 Wien Austria Europe Please keep a copy of your data and logs in case some mail gets lost.

In case the mail/ftp servers go down, there is an alternate email address for use in contacting the control center: wholeearthtelescope@yahoo.com