Mon R2 Monitoring
We are attempting to measure the flux density of the excited state 4765 MHz OH masers in Mon R2 (06:05:21.6 −06:22:27.0 B1950) approximately once per week. At the moment (October 2007), the peak emission is around 50 Jy and the source can be seen in a 5 second integration on SPD.
Basic setup instructions:
- Select 4.8 GHz receiver on multifeed system (receiver 4), and put this receiver on axis see Receiver Positions And System Temperatures Table
- Make sure that the hybrid is out (and if not, switch it out using the receiver control computer).
- Set the agilent to a frequency of 10.5 GHz and level of 17 dBm.
- Follow the instructions Setting up for a Multibeam Correlator Observation. The specifics for Mon R2 are that the SMY should be set to 617.0 MHz and the DAS profile to COR4000.PRO. NOTE: There have recently been some problems getting this particular DAS profile to work correctly, if the bandpass looks wrong in SPD, first try reprogramming the configuration in tkcor, and if that doesn’t work then restart the DAS (see Computing Instructions for details).
- Make sure levels into the DAS and square-law detectors etc are OK.
- Check that the correlator is plugged into the DAS - the eVLBI recorder can also use the correlator outputs from the DAS so it’s common to have to fix this.
- Start the Mon R2 observations by issuing the commands
/usr/local/pkg/correlator/survey_ng -a sys26m -c hobart -i 0 -n 2 -r rakbus -s sam26m -f mon_r2.out
in an xterm on hobart.
- Use SPD to look at the initial data collected. The first observation is a 10 minute reference, so you shouldn’t see any maser emission, but the bandpass should be relatively flat.