Do the DP0 data catalogs contain proper motion or parallax measurements?

Tags: #<Tag:0x00007fdd77c252c0>

Do any of the DP0 data catalogs, based on the DC2 data set, contain proper motion or parallax measurements?

In The LSST DESC DC2 Simulated Sky Survey, Section 5.3 “The Local DC2 Universe: The Milky Way” does indicate that stars are assigned proper motions and parallaxes as part of the simulation.

However, as described in Section 4.2 “The Instance Catalogs”: “Since version 19.0.0 of the LSST Science Pipelines, which we used for image processing, cannot handle proper motion and parallax of stars, we omitted those effects from the instance catalog entries”.

Thus, none of the catalogs available for DP0.1, as listed in the DP0.1 Data Products Definitions Document, contain parallax or proper motion measurements.

And they don’t have the proper motions or parallaxes simulated! (Not just not measured, but not simulated).

1 Like

Thanks this is very helpful to know.

1 Like

(just to be really clear for anyone reading)

That’s right. The instance catalogs are the inputs to the image simulations.

We had these effects in DC1 but DM couldn’t correct for it and it caused a bias. This was still the case when we made DC2 so we didn’t write the effect into the instance catalog and they weren’t included in the simulations.

1 Like