Software for Deep Survey How useful are tools developed for HIPASS for ALFA surveys? HIPASS members in DEEP working group Software not specific to DEEP survey Initial assessment by Martin Zwaan Wolfram Freudling

Tools developed for HIPASS Livedata: On-line/off-line processing software removes bandpass calibrates the spectra applies doppler tracking, smoothes and baselines the spectra has an excellent capability for visualising calibrated spectra Gridzilla: takes spectra from a collection of bandpass-calibrated measurement sets and writes a 3-plane cube Both are aips++ packages (Solaris/Linux, not Mac) See: for desciption of tasks Both were specifically designed for Parkes Multibeam, but could be easily modified to work for ALFA Viewgraphs prepared by Martin Zwaan (ESO)

Livedata GUI scheduler Bandpass calibration Multibeam reader Data monitor

Gridzilla GUI

On-line monitoring Monitor display  livedata Statistics tools  livedata RFI id & removal  /  (median filtering removes some RFI) NVSS cross reference  1 beam bandpass  livedata 1 beam spectra  livedata Quick-look T-F maps  livedata Quick-look X-Y maps  (maps made with gridzilla, not on-line)

Level I processing Bandpass subtraction  livedata Continuum subtraction  by LUTHER (fits and subtracts templates) Flux calibration  livedata Higher level RFI excision  Astrometry  (not an issue for HIPASS…) Gridding  gridzilla Level 1 CLEANing  (HIPASS sources unresolved so no deconvolution. Need to do this for ALFA) Level 1 spectra  livedata Level 1 maps & cubes  maps & cubes only level II Continuum catalogue in progress (David Barnes) (level II) Data validation process  livedata Level 1 access tools  livedata Level 1 documentation  see ATNF/HIPASS webpages Level 1 software export  Level 1 archive 

Level II processing Level II CLEANing  (is required for ALFA) Level II spectra  livedata Level II maps  gridzilla Level II cubes  gridzilla Data validation  livedata Level II archive  FITS cubes Level II access tools  Level II documentation  Level II software export  Portal to NVO the HIPASS catalogue is VO compliant, the cubes are not

Level III Data & Software Tasks Baseline fluctuations  livedata Noise characteristics  livedata Sidelobe “cleaning” schemes  livedata Object finding algorithms  peak flux/wavelet (see Meyer et al 2004) Template fitting ? Injection of fake sources  lesson from HIPASS: need MANY! (see Zwaan et al 2004) Extended vs. point sources  not a big issue for HIPASS (see M04) Detection documentation  M04 & Z04 Data validation process ? HI source catalogue  Survey simulator  why? ALFA simulator  Overlay tool  Drinkwater et al in prep Catalogue Xreference tool  ditto Toolkit documentation 

Level of effort to convert to ALFA “pskread”  “alfareader” –Converts data to glish format which can be continuously read Time dependent bandpass estimate, depends on observing strategy Cleaning RFI treatment Modify line spread function by clever smoothing (convolution)

Issues AIPS++ support? Date rate Parkes: 1024ch * 2pols * 13 beams every 5 sec= 26* 1 kByes/sec ALFA data rate: 8194 * 2pol * 7 beams ~ factor of 5 bigger than Parkes