*IVOA May 2021 Interoperability Meeting - DAL/Radio session *Time: Wednesday May 28 05:00 UTC participants:49 *schedule Baptiste Cecconi - TFCat - Time-Frequency Catalogue Hendrik Heinl - LoFAR DR1 VO services Ricardo Rizzo - Radio Astronomy projects in the Spanish VO Julian Garrido - Study of provenance data for the SKA Science Data processor *Notes *Baptiste Cecconi - TFCat - Time-Frequency Catalogue Low frequency radio - spectro-temporal data products key for science. Features strongly time dependent - origin can be distinguished by polarisation. Also want to charcterise shape - tops of spectral features etc Cross-over with IHDEA for solar physics No support for spatia-temporal in VO-STC or VO-??? but could look to geon-json TFCat model - TF geometry combines shape with time and frequency. Also normal votable features such as field metadata and global properties Can map most fields between VOCat and VOTable Current implem - Geo Json based * Can use TAP for query and distro * WOrks with astropy votable Overlay of catalogues over jupiter dynamic spectrum - shapes show outlines of features *For TAP out json into geometry column but then can't use ADQL to query insde column Added TFCat to autoplot via embedded jython script Other user cases such as pulsars, FRB, GW - helps with input to machine learning models Markus: Has GeoJSON come up with a replacement for the old CRF that (I think) they had deprecated? [BC] Ada Nebot: Looks neat. GW community - use MOC and attach data to it Francois Bonnarel: If ST-MOC is not extended to energy/frequency in the near fututre could still simulate in STC-string ascii BC: STC cannot express mixed time and freq that I know FB: Thought that had come back - discussion needed Mark Taylor: x-type - could just put tf-cat in the x-type and make it a defacto standard *Hendrik Heinl - LoFAR DR1 VO services Demo of Astron server with TOPCAT Quite a few tables to link sources with images and/or visibilities mosaic names are the links between catalogues and images but they don't have exactly matched names. IMages have size in them Called mosaic_id in lofar table but again it is mosaic name and lofar image has "mosaic" appended Join then requires string concat with known extra text - complex for users Examples are really useful in these cases if joins require extra work Radio image sizes are huge - averga size in 100s of MB or GB for the LOFAR survey images Metadata doesn't always identify table differences Solutions: * Cutouts to the rescue for large file sizes * python driving SODA service with sources from e.g. simbad (so we have angular size) * pvo samp doesn't support some desired features * Generates cutouts and sends to aladin Would love to see more datalink and more SODA for radio [FB]: astron Images are also in ivoa.obscore - may be easier to find them there Severin Gaudet: Also looking at source catalogues, datalink, SODA to produce cutouts. *Ricardo Rizzo - Radio Astronomy projects in the Spanish VO Just starting out in IVOA - looking to integrate products into VO SiO Catalog * SiO maser at 7mm to 1mm * Spectra towards oxygen rich stars * 61 different maser lines * then 2 telescopes x 2 pol x 5 bands x 67 stars * 4000+ spectra with potential wide applicability * Built VO service using SVOCat * FITS and preview images available * Also web front end for querying and retrieving data MADCUBA * Suite based on imageJ for large data cubes * Processing images and spectra - fitting and identifying line params * Fitting can be tuned or automatic * Considering outputing synthetic cubes and making available with SIA2, datalink and SODA(?) * IVOA radio note very helpful FB: How do you access ALMA cubes? RR: MADCUBA team is working with a container that user provides data. Scripting access to ALMA arvchie or via local files *Julian Garrido - Study of provenance data for the SKA Science Data processor Science Data Processor - will be where data is computed and analysed Metadata analysis - conceptual data model and pipelines Data will be sent to Science Regional Centres (SRC) where scientists will access the data Science Data Model will have some data not sent to SRCs Provenance data will sit in the Science data model Examined modeling data product catalogue with Provenance-DM standard * Found it best to model data products as entities * Still high level - still scope to split it and define it in further detail Also looked to model pulsar search workflow in provenance DM * successfully modelled workflow as prov activities SDP workflows are quite big and complex. Examined using ProvOne as it is aimed at more complex workflows * Could connect central part of Prov One DM with IVOA DM - can then have high level view as well as the very detailed view of computation * Two views usful as not everyone wants the full detail Examined visualisation * Static visualisation not scalable to SDP * Prov viewer interactivity was good but is a desktop app so not suitable fr archive * Prov store web service -basic visualisation - but no search FB: Have you seen CTA work? Have you seen ProvLog??? package JD: Have encountered it this week, will examine FB: IVOA prov group to contact