LSST AGN

AGILE: AGN In the LSST Era

AGILE is a project (developed as part of the Italian in-kind contribution to LSST) aimed at creating a realistic LSST photometric catalog and images (DP0-like) which include not only galaxies but also stars and AGN. The final deliverable consists of three main products: the truth catalog, simulated images, and the photometric catalog extracted from the images.

This is a schematic view of how the AGILE pipeline works:

Step 1: Creation of the truth catalog containing Galaxies, AGN and stars

  1. Galaxies: We start from an empirically calibrated galaxy sample with redshifts, stellar masses, star-formation rates, and morphologies generated using EGG (Empirical Galaxy Generator; Schreiber+ 2017) and the most up-to-date measurements of the stellar mass function (COSMOS2020; Weaver+ 2023) up to z ~ 5.5.
  2. AGN: We then populate galaxies with AGN whose properties are based on empirical recipes:

In detail:

3. Stars: Finally, the Milky Way and Magellanic cloud single and binary stars are added from the publicly available LSST SIM database, which is based on the TRILEGAL code (Girardi+ 2012). Variability is included also for the star catalog.

Step 2: Simulated multi-band LSST images (ugrizy):

The AGN+galaxy+stars truth catalog is then fed into the LSST image simulation pipeline Imsim (https://www.lsst.org/scientists/simulations/imsim), which takes into account instrumental effects, sky background, and the LSST cadence, to generate simulated multi-band images in the Rubin-LSST bands, i.e. u, g, r, i, z, y (and possibly also Euclid VIS+NIR bands). For the current release, we have used the LSST baseline 4.0. In Fig. 1 we show the r-band image corresponding to 1 patch (0.05deg2) with overplotted type-1 AGN (orange circles), type-2 AGN (green circles), galaxies (red circles) and stars (violet).

Fig. 1: r-band image corresponding to 1 patch (0.05deg2) with overplotted type-1 AGN (orange circles), type-2 AGN (green circles), galaxies (red circles) and stars (violet).

Fig. 2 and 3 show a zoom-in to the individual 30s calexp images and coadded images. The panels correspond to ugrizy (left to right, top to bottom).

Fig. 2: Zoom-in to the individual 30s calexp images. The panels correspond to ugrizy (left to right, top to bottom).
Fig. 3: Zoom-in to the coadded images, corresponding to a total of 1,441 visits. The six panels correspond to ugrizy (left to right, top to bottom). The r-band image shows the locations of AGN type1 (circles) and AGN type2 (squares).

Step 3: Building realistic catalog-level simulated data:

On the simulated images we then extract the photometric catalogs using the official LSST photometric tool (https://pipelines.lsst.io/index.html) in order to create a realistic LSST photometric catalog. 
Fig. 4 shows an example of simulated SED (black line) with overplotted the extracted realistic fluxes (circles) while Fig. 5 shows a simulated AGILE type1 AGN lightcurve (solid line) with fluxes (circles) extracted in the imSim simulated images using the LSST Science Pipelines.

Fig. 4: Example of simulated SED (black line) with overplotted the extracted realistic fluxes (circles) in ugrizy bands
Fig. 5: Simulated AGILE type1 AGN lightcurve (solid line) with extracted realistic fluxes (circles) in ugrizy bands

THE FIRST DATA RELEASE DR1: NOW AVAILABLE!!

The first data release consists of the following products:

  1. Truth products for 24deg2

2. Simulated images for the central 1 deg2 (21 detectors), 1441 visits, and 3 yrs of COSMOS

3. Photometric catalogs for the central 1deg2, 1441 visits, and 3 yrs of COSMOS


HOW TO ACCESS THE DATA

1. Google DRIVE which includes:

2. ADHOC Newton server (https://www.fisica.unina.it/ricerca/grandi-attrezzature/adhoc)

All data (master.db, Deep Coadded images and SINGLE VISIT IMAGES)

If you want to use single visit images and access the data directly in the server, please write us!

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