Usage of the ACE spectrograph on the RCC

Logging in

The RCC telescope can be controlled from m6. To access the computer, you can use ssh, for example: ssh -X user@m6.konkoly.hu where user is your username on m6.

Note: until recently, m5 was used as a control computer for the RCC. Everything from m5 has been migrated to m6, a Virtual Machine running on m9. Nevertheless, if you find anything missing, notify the support astronomer.

For observing, it is advised to use the screen utility, see its description here: Usage of the screen program

As an alternative to ssh, you can use X2GO, which gives you remote access to the graphical user interface. See its description here: Usage of X2GO

Turning ON the cooler

At the start of an observing week, you can turn on the spectrograph water cooler [1] as follows:

• • Check the IP Stecker on http://172.31.171.99 , Login: admin, FLI,CHILLER ON.
  • Restart the ALIX on the IP Stecker.
  • Wait for two minutes.
  • On m6: cooler --start, cooler --status.

If the weather is predicted to be bad for a few days, consider turning off the cooler. Try to avoid turning it on/off too frequently.

Starting

• Enter your working directory in a console: cd /data/user/YYYYMMDD Always save your fits files into the /data folder, not into your home directory!

• In a console type: rcc-test If everything is green, proceed further. If not, contact the support astronomer.

• In a console type: acectrl --status If Main pickoff mirror is on, the telescope is ready for spectroscopic observations. If not, type acectrl --start. For help see acectrl --help

• Start ds9. Check the telescope: http://ccdsh.konkoly.hu/static/tmp/prcc-state.html?refresh=60

• Start CCDSH in a console: ccdsh (preferably from screen, see Usage of the screen program).

• If your .ccdsh_startup file is not prepared for the usage of the spectrograph camera, type in CCDSH: CCD> source /usr/local/ccdsh/scripts/load-spec.ccdsh This will load the camera driver.

• Type CCD> status; rcc status in CCDSH. If everything is green, proceed further.

• Check the camera temperature in CCDSH: CCD> get temperature If it is not cooled down, check the status of the cooler (should be turned on): cooler --status Cool down the camera: CCD> set temperature -40 If the temperature difference between the actual temperature of the camera and the target temperature is big, cool it down in two steps. In summer, the target temperature should be -35 Celsius, in other seasons -40. Check CCD> get temperature, whether the cooler can keep the desired temperature (the power stays below 100%). Generally, do not go below -45 in summer, or below -50 in winter. You can check the weather information with pszk-met, and the Coudé room temperature and humidity at http://ccdsh.konkoly.hu/rccroom/.

• Cool the guider camera. Type in a console: rcc-autoguide.qsi --temperature -20 (or use a value around -15 in summer)

• Open the dome slit. In CCDSH: CCD> set dome slit open

• Start the tracking: CCD> set mount track on

• Start the automatic dome rotation: CCD> rcc dome auto

• Open the tube and mirror covers: CCD> rcc tubecover open

• After 30 seconds: CCD> rcc mirrorcover open

• Type CCD> rcc status. If everything is opened and green, proceed.

Focusing

• Set the spectrograph mode appropriately. Probably you would start with taking a few ThAr spectra, so use acectrl --mode thar. Starting with some ThAr spectra can easily check whether the bench collimator optics is in focus and such spectra can also be taken while waiting for the bench camera to completely be cooled down.
• If the ThAr spectra are slightly out of focus, use acectrl --spectrum-focus [+|-]step to fine-tune in the focus position. Usual increments are around +/-100. If the ThAr spectra are completely blurred, reset the collimator focus using acectrl --spectrum-reset and then start tuning with the focus. Don't forget to explicitly specify the sign of focusing steps!
• The exposure time and gain values used by the on-axis fiber camera can be controlled with the program mintronctrl: mintronctrl -g 6 -e 5.
• Turn on the auxiliary LED on by acectrl --led 0.7.
• Watch the live image of the on-axis camera. If needed, adjust focus of the on-axis fiber camera optics with acectrl --fiber-focus [+|-]step. Usual increments are around +/-10. The default value is around 1160.
• Turn off the auxiliary LED on by acectrl --led 0.
• In a single run, never change the focus of the fiber camera optics once set properly.
• Use the CCDSH focusing command CCD> set focus 81.2 to focus the telescope in order to have a sharp image on the on-axis fiber camera (the approximate telescope focus value for the spectrograph is around 81.2, depending on the weather conditions). As an alternative, you can use CCD> rcc autofocus apply, which sets the focus depending on the current temperature.

Observing

• If the camera is cooled, take same ThAr spectra and save them. Use exposure times between 1...5 seconds: CCD> !acectrl --mode thar; !sleep 4; sequence -n %N-%F-thar-1s 1*([object,time=1]); !acectrl --mode science This command first changes to ThAr mode, waits 4 seconds, takes 1 ThAr spectrum with 1 second exposure and turns back the spectrograph to science mode. As the strong emission lines of the ThAr lamp can saturate the pixels of the CCD, it can be useful to read out a few empty frames afterwards (e.g. with CCD> acquire -t 1).
• In a single run, never change the bench focus position once set properly.
• Turn the spectrograph into scientific mode with acectrl --mode science.
• Open a browser window to monitor the fiber camera on https://ccdsh.konkoly.hu/aux/rcc/onaxis/video.mjpg
• The exposure time and gain values used by the on-axis fiber camera can be controlled with the program mintronctrl: mintronctrl -g 6 -e 5
• Check the visibility of your target: CCD> staralt 'beta cvn'
• Slew the telescope to the desired position: CCD> slew 'beta cvn' In case of any problem, you can stop the slewing process by CCD> set mount stop. This will turn off also the tracking of the telescope. Check the position of the telescope on the "LSD" plot: https://ccdsh.konkoly.hu/img/prcc/state/mountaxes.png. Do mind the northern column and the artificial horizon denoted with solid red lines on the plot. For a detailed description of the "LSD" plot, see: https://ui.adsabs.harvard.edu/abs/2016ExA....41....1P/abstract.
• Tweak the telescope position (using CCDSH or the program rccpanel) in order to move the target star behind the fiber. If your target is not where you want it, type in a console: rccpanel --speed 8 &. This will bring up a small panel. With the arrows you can move the telescope. You can adjust the speed, max. is 10. Check the position again with a test image. If the target is where you want it, start the autoguiding. First, create a test image with the guider from the console: rcc-autoguide.qsi --exptime 10 -o x.fits And open it with: xpaset ds9 fits < x.fits If there are more than 10 stars, you can start the autogide with this command in a console: rcc-autoguide.qsi --exptime 10 --relax 5 --point This will do a 10 seconds exposure, and wait 5 seconds until the next. And in the meantime it will adjust the position of the telescope. If you have less than 10 stars in the guider FOV, use the --fine option, instead of the --point. As an alternative, or when no stars are found, you can use the analytic guider with rcc-guide (check rcc-guide --help for help). Typically, rcc-guide is less effective than rcc-autoguide.qsi, hence it is a good idea to check whether the star is on the fiber regularly (e.g. in every 5-10 mins) when using it. Stop autoguiding only during "Relaxing" using ctrl+c. Stop autoguiding first if you want to move to an other target!
• Take spectra: CCD> sequence -n %N-beta_cvn-60s 10*([object,time=60]) This will take 10 images with 60 seconds exposure time. The output fits image name starts with the date. For a quick check, you can take a 60 second exposure with CCD> acquire -t 60, without saving it.
• Take ThAr spectra regularly, at least 2-3 times per night. The frequency of such spectra depends on the scientific accuracy needed by the actual observations. In general, the larger the thermal stability of the bench, the less frequent the ThAr spectra have to be taken.

Calibration frames

You can take bias and dark frames with:

CCD> sequence -n bias 10*([bias])

CCD> sequence -n dark-60s 5*([dark,time=60])

To take flatfield images, turn on the flat lamp with acectrl --mode flat, and run:

CCD> sequence -n flat-5s-%N 10*([object,time=5])

The lamp illuminates the CCD directly via a fiber, so you don't need to move the telescope anywhere. A few seconds of exposure time is usually enough. Once finished, turn off the flat lamp with acectrl --mode science.

Also, don't forget to take ThAr images regularly.

Closing

When you finished observing, stop the autoguider when it is in a relax state with ctrl+c. Also, you can stop a sequence or a script with ctrl+c.

Warm up the guider camera. In a console: rcc-autoguide.qsi --temperature off

Stop the spectrograph: The following series of commands should be executed:

• Turn the spectrograph into scientific mode with acectrl --mode science. This command will also switch off the ThAr lamp and flat lamp if these were turned on before.
• Also ensure that the auxiliary LED is switched off with the command acectrl --led 0.
• Check the status with acectrl --status. The above two commands ensure that no light sources are left turned on and hence the spectrograph frontend box is completely dark. This is essential if alternate instrumentation mounted below the frontend box is going to be used.
• Turn off the spectrograph with acectrl --stop.

In CCDSH:

• CCD> set mount track off
• CCD> rcc dome manual
• CCD> rcc mirrorcover close
• After 30 seconds: CCD> rcc tubecover close
• CCD> set dome slit close
• CCD> rcc slew 0 47.8
• CCD> set dome azimuth=156.3

After a few minutes, check that everything is OK and closed: CCD> status; rcc status

Turn on the lights in the dome: CCD> set dome light 1 on/off

Check the telescope on the webpage: http://ccdsh.konkoly.hu/static/tmp/prcc-state.html?refresh=60

Turn off the lights in the dome: CCD> set dome light 1 off/on

After you finished making the calibration images you can warm up the camera: CCD> set temperature 0 Once this temperature is reached, you can turn off the camera cooling with: CCD> set temperature off

The temperature of the camera should rise slowly. You don't have to warm up the camera completely, but in case of storms and other anomalies it is recommended.

Turning OFF the cooler

At the end of the week observing with the spectrograph, if the spectrograph will likely not be used for at least 3-4 days, you can turn off the water cooler [2]. Try to avoid turning it on/off too frequently (i.e., don't turn it on/off every day). Make sure to warm up the camera beforehand from CCDSH with set temperature 0 and set temperature off.

• • Warm up the camera in ccdsh.
  • On m6: cooler --stop, cooler --status.
  • Log in to the IP Stecker (http://172.31.171.99) and turn off the FLI and the CHILLER.

Troubleshooting

In case of any problem, consult the Troubleshooting page and/or notify the support astronomer. If you are the support astronomer, document the problem on Internal:RCC_error_log.