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General Issues

All UK pipeline processed data will be archived online in the UK, with raw data probably being stored off line ``on a shelf''. There does not appear to be a compelling need for a near-line ``tape'' robotic storage system ?

Observing strategy for the interleaved mix of UKIDSS survey and PI observations is a further issue that needs addressing. This should take into account interactive feedback from derived DQC information and optimising data taking sequence to address sky variablity issues and so on. We suggest that the JAC $+$ UKIDSS survey project scientist should be responsible for overseeing the development of the toolkit required to do this.

Test observations to answers question regarding image persistence, possible intra-pixel sensitivity problems, non-linearity monitoring and so on ... who is organising them and guaranteeing that they are addressed ?

Setting up photometric standard fields covering entire FOV - see related photometric calibration document.

It is crucial that accurate, agreed and complete FITS headers are attached to all files for automatic pipeline processing (details TBD but should also include site monitoring information). A FITS header (and data) verification program should be run on all summit-produced FITS files before export to the UK. Any faults should be fixed in situ before shipping.

Are there science requirements for real-time data processing on the summit ? eg. transient event detection such as moving objects, variables ..., and related to this, are data products other than DQC information required at summit ?

Constraints on interleaving and dither patterns from non-linear astrometric field distortions to avoid pixel interpolation schemes - tiling will undoubtedly require non-linear resampling in all cases. The envisaged astrometric field distortion for WFCAM implies that for ``dithers'' up to $\approx$20 arcsec, non-linear resampling will not be needed for stacking data within one device. Satisfying this constraint is desirable for various reasons.

Defining a standardised set of parameters for each detected object describing the image location, the flux, the shape and error estimates for these parameters (details TBD but see Appendix C for starting point cf. also with SuperCosmos, APM, SDSS, 2MASS)

Undersampling and intra-pixel sensitivity variations problems

How to deal with bright stars, ghostimages, trails ? One possiblity it to use input predictions for positions of bright stars, galaxies, globular clusters, solar system objects and so on.

Do we want image atlases for extended sources ? - colour pictures ? directed public outreach products?

Community input on data processing products and requirements - UKIDSS is represented directly is there a need for wider consultation ?

Documentation and release of software ? Should we release the pipeline software ?

Official UK set of survey data products - can be multiple copies ? Continuous -v- staged release of survey data products ? Publication of survey and responsiblity for that ?

next up previous
Next: Outline of Basic Pipeline Up: APPENDICES Previous: Glossary of Terms
Nigel Hambly 2002-10-02