Observing Instructions XCOV30 Oct/Nov

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1 Observing Instructions XCOV30 Oct/Nov Purpose and Plan: 1) Primary Targets: a) NGC 1501 RA: DEC: Epoch: 2000 V=14.36 (central star) NOTE: This is a planetary nebula b) WD RA: DEC: Epoch: ) Secondary Targets: a) G29 38 RA: (2000) DEC: (2000) V=13.03 b) G38 29 RA: (2000) DEC: (2000) V=15.6 3) Finder charts Headquarters: We will have a virtual Headquarters running between approximately Oc 25 Nov 9. All communications will be via at darcdelaware@gmail.com. We may also be using a Google Hangout. Details will follow. Data Upload: Data may be uploaded directly to darc@daedalus.physics.udel.edu with sftp or scp. A user account has been set up for this purpose, and the password and user name will be distributed shortly. Please upload all data to /home/data/incoming, Use sftp or scp. You will find a directory named according to your observatory (4 letter code). Please put all of the data from one night (images AND calibration files) into a subdirectory named for the date of the observations. We will be receiving data from multiple telescopes, so please do not use a different directory. We don't want to miss any data in the rush.

2 Contact during run: If any problems arise during the run, please contact any of the following: Best Contact: darcdelaware.at.gmail.com (please note the at ) Judi Provencal jlp.at.udel.edu Gerald Handler gerald.at.camk.edu.pl Paulina Sowicka: paula.at.camk.edu.pl Time Check: Please do a clock check each night before taking data and verify your time. Check your clock visually as often as possible during each observing run. You can check your time against the USNO Java Clock ( If your clock shows a drift during the night, include this information in your observing logs, and send to one of the contact people so it can be accounted for in the data reduction. Headquarters will also be available for time checks. CCD Observers: Naming Conventions: The most important rule is to BE CONSISTENT with your run/image names from night to night. If possible, name your runs according to the UT DATE when you begin the time series and the star you observe. For example, if you are at Mount Cuba Observatory, observing NGC1051 on (UTC), your image names would include mcao ngc1501, and thus each CCD science image would be mcao hs fits etc. Your flats would be mcao flat.0001.fits etc. See last page for suggested observatory abbreviations. Normal Calibrations: Bias: Take bias frames (zero time exposures) at the beginning of each night, and again at the end of the night. We would like to look for drifts in bias during the night due to temperature variations. Darks: Take 10 dark frames at the beginning of each night. The darks can be at the exposure time of your science images, or you can use longer exposure times (5 or 1 minute darks). Flats: Dome flats: If you choose to do dome flats, please take 30 flat field images per night. Choose an exposure time that fills your CCD to half its

3 saturation level, but is long enough that shutter opening speed is negligible. Please take dome flats using your filter. Sky Flats: If you take sky flats, take as many as possible in the time you have. Use a high elevation field away from the setting sun. and be sure to use your BG40 or S8612 filter (or the same filter as the science images). Exposure time: NGC1501 and G29 38 These are fairly bright targets. For large telescopes, choose an exposure time such that the resulting image does not approach the saturation level of your CCD. Try to include at least one comparison star of similar brightness (or brighter) than your target. It is important that the total cycle time be significantly shorter than the pulsation periods of our targets. For NGC1501 the pulsation periods are between minutes. We can tolerate cycle times as long as seconds. For G29 38, the pulsation periods are around 10 minutes. Aim for total cycle times less than 30 seconds. WD0246 and G38 29 These two targets are significantly fainter than NGC1501 and G You will need to balance cycle time with exposure time. For smaller telescopes, you should aim for counts above sky level at the center or the focused star. CCD binning: If appropriate, bin your CCD to decrease readout time. Be sure that the star images still fill an adequate number of summed pixels, and there is sufficient area for sky measurements. Again, it is necessary that the complete cycle time (exposure + readout) be significantly less than the pulsation period of the object. Filters: For NGC1501, it is important to suppress the nebula emission. If you have a BG39 or BG40 (S8612) filter, please use that. If not, please use a V filter. For the pulsating white dwarfs, please use a BG40 filter where available. Amplitudes are important, so please let us know which filter you are using. Make a note of the filter name (or lack thereof) in your log and if possible in the header of your fits files. If no filter is available, we will require your CCD s quantum efficiency versus wavelength. Finder Charts: Finder charts are available on the web site. Please try to include at least one comparison star that is at least as bright as your target. If a sufficiently bright comparison star is not within your field, you may need to increase your exposure time so dimmer reference stars have a significant number of counts above the sky level

4 Time Check: Please check the clock that is recording the time in your headers against a standard clock every night. You may use the Internet clock found at Even if you cannot change the clock, do this sanity check for us and note that you performed a time check in your log. Also, please note if there is any discrepancy in your clock. Logs: Keep a text log each night. We suggest a name similar to your image names. In this log, please give the star name, date, time, observers names, filter, basic weather conditions, number of images on each target, and any information you feel will help us reduce the data. Please include this file when you upload your data. Night Reports: We have created a web form so you can immediately let us know that you got data or were clouded out. Click on the Night Report tab on the XCOV30 run page. Please fill out the form every night, even if you don't observe. It will update table so you can inform the entire collaboration that you have obtained data. Suggested Observatory abbreviaions braz, Brazil LNA kpno = Kitt Peak ctio = Cerro Tololo hawa, hawaii krak, Krakow hvar, Hvar mcao, Mount Cuba mcdo, McDonald Observatory sara, SARA soar, SOAR mtjo, Mount John, mtlm, Mount Lemmon naos, NAOC 0.5m naob, NAOB 2m pjmo, Meyer Observatory prom, Prompt 0.4m saao, SAAO 1m suho, Suhora terb, Peak Terskol 2m ters, Peak Terskol 0.6m teub, Teubin

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