Colloquium Abstract - Dong - 2025Feb07

February 7, 2025

11:00am Mountain

Dillon Dong (NRAO)

 

Science at scale with the VLA Sky Survey

 

Abstract

In October 2024, the VLA Sky Survey (VLASS) completed its third full epoch, observing all ~34,000 deg² accessible to the VLA at S band with a ~140uJy RMS and a ~2.5 arcsecond resolution for the third time since 2017. Thanks to the efforts of the VLASS team, all observations have now been data-analyst-vetted and processed through the Stokes I quicklook imaging pipeline, enabling high-quality, multi-epoch measurements of ~99% of the surveyed area. The ~106,000 quicklook images represent a ~2 order of magnitude reduction in volume from the raw visibilities, transforming a nearly petabyte-scale problem to a ~5 TB dataset well within the processing capabilities of modern workstations. In this talk, I will discuss several ongoing efforts to distill these data further (into data products and science) and make them readily available to all. This will include: (1) a preview of the VLASS transient catalog: their demographics, rates, multi-wavelength counterparts, and new scientific windows they open up, (2) stacked quicklook images and the corresponding persistent source catalog, and (3) a new VLASS image cutout server capable of delivering cutouts at arbitrary locations in ~100 milliseconds per coordinate.


Local Host: Lilia Tremou

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