Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.mrao.cam.ac.uk/~bn204/almasim08/papers/discuss.pdf Дата изменения: Tue Dec 2 15:00:32 2008 Дата индексирования: Tue Oct 2 10:44:14 2012 Кодировка: Поисковые слова: voyager 2

Simulations for ALMA: Discussion points

Robert Laing European Instrument Scientist

Simulations for ALMA IRAM, Sept 8 -11 2008


Issues for the user


What simulations are needed to help (inexperienced) users?


Easy interface, particularly for input of source models Library of examples Closely linked to ALMA-OT Initial simple filters: is source accessible; field of view; range of spatial scales; rough sensitivity Residual design issues (pad locations) Commissioning issues (what do we expect from small numbers of antennas?) Preparation for Early Science
ALMA 2 Simulations for ALMA



Priorities


Robert Laing European Instrument Scientist


Collaboration between simulation groups


Groups working within different reduction packages and analysis frameworks


CASA/almasimmos; Miriad; GILDAS; Viallefond; Nikolic Different strengths and weaknesses; different effects simulated How to preserve the benefits of working in familiar environments while sharing and comparing results? Interoperability? Common routines? Interchange formats (data, metadata)? UVFITS sufficient?



What can we do to promote collaboration
ALMA 3

Robert Laing European Instrument Scientist

Simulations for ALMA


Technical Issues


Voltage patterns


Critical for I and polarization Start with EM simulations; then use measurements Can we do better than MEM / multiscale clean? NNLS, subtraction of model voltage patterns in uv plane Exploit redundancy in uv plane Coming soon in CASA?



Deconvolution issues:




Pointing self-calibration


Phase transfer between frequencies Heterogeneous arrays (SD + ACA + 12m array)


in hand
ALMA 4 Simulations for ALMA

Robert Laing European Instrument Scientist


Technical Issues (2)


Multiple configurations


Will be essential for very wide ranges of spatial scales Demonstrations Cross-calibration issues

Robert Laing European Instrument Scientist

ALMA 5

Simulations for ALMA