Discussion 4: Current observing issues at Parkes

G. Hobbs

Topics

The purpose of this discussion is to identify and, if possible, fix some of the current observing issues at Parkes. The PPTA project currently uses the prototype digital filterbank system (PDFB1) and CPSR2 (sometimes the WBC). Early next year we should be using the new digital filterbank (PDFB2). This system will provide the possibilities of a folded-data mode, search mode and output baseband data for coherent dedispersion. Later in the year we expect that the new coherent dedispersion system APSR will come on line. The receiver systems mainly used to date are the 20cm multibeam receiver and the 10/50 dual-band system. The 20cm multibeam is currently being refurbished and will not be available until May 2007. The HOH receiver will be used instead. The 50cm band is seriously affected by digital TV transmissions. Consideration is being given to an RFI mitigation system that will work in conjunction with the PDFB2 and to changing the receiver (to observe in a cleaner band).

The observing techniques etc. have been documented by John Sarkissian. The pulsars have been given a ranking to allow the observer to choose between two pulsars (at 20cm). However, it has been noted that such a ranking does not exist for observations using the 10/50cm receiver. The data are stored on disk at Parkes and the DFB/WBC data pre-processed by John Sarkissian. The CPSR2 are pre-processed by the Swinburne group. Scripts now exist that copy the data to Epping. John S. is providing an email report at the end of each observing session.

At Epping the data are processed using automatic scripts that produce scrunched archives and timing residuals.

Topics for discussion include:

• The RFI environment and mitigation
• The status of the final DFB system
• Status of APSR
• Documentation and reliance on John R. to set up unusual observing modes
• Optimising our observing due to scintillation, RFI and windparks
• Do we all know how to access the data as required?
• The Parkes observing log (what is it and why aren't we using it!)

Structure of meeting

• Overview (G. Hobbs, 10 min) - will provide an overview of this discussion and provide information on the current status of the new DFB system.
• The current RFI environment at Parkes (John S, 5 min) - will provide information on the current RFI environment at Parkes and the likely future RFI situation.
• Status of CPSR2 and APSR (A. Teoh, 5 min) - will explain to us how to use CPSR2 in 4-bit mode . Will provide a few notes on the current status of the APSR project.
• A proposal for optimising our observing at Parkes (J. Verbiest, 5 min) - will highlight problems with our current observing setup - including suggestions for prioritising our pulsar list.
• Remote observing possibility (F. Jenet, 5 min) - will explain his Arecibo Remote Control center (ARC) project in Brownsville and discuss the possibilities for Parkes observing.