DIA object#

Derived properties for transient and variable objects.

Schema: DiaObject table

Access#

The DIA object table is accessible via the TAP and Butler services.

Recommended access service: TAP

TAP#

Citation: NSF-DOE Vera C. Rubin Observatory (2025); Legacy Survey of Space and Time Data Preview 2: DiaObject searchable catalog <doi-tbd>
Table name: DiaObject
Columns: <tbd>
Rows: <tbd>

Butler#

Citation: NSF-DOE Vera C. Rubin Observatory (2025); Legacy Survey of Space and Time Data Preview 2: dia_object dataset type <doi-tbd>
Dataset type: (‘dia_object’, {skymap, tract}, ArrowAstropy)
Format: Parquet
Number of Butler datasets: 25

Description#

A “DIA object” is an astrophysical transient or variable object at a static sky coordinate.

The DIA object table is created by associating DIA sources within a 1 arcsecond radius. DIA objects are assigned to a tract and patch based on their RA, Dec at radecMjdTai. DIA objects are only created in the non-overlapping tract and patch inner regions.

The DIA object table contains derived per-filter variability parameters such as the minimum, mean, maximum, standard deviation and skew in the difference-image fluxes, and the light curve’s slope, percentiles, and StetsonJ parameter.

Processing#

The DIA object table is the result of Difference image analysis (DIA).

Tutorials#

See the 200-level catalog Tutorials for a notebook on the DIA object table.