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Title: The First Palomar Gattini-IR Catalog of J-band Light Curves: Construction and Public Data Release
Abstract Palomar Gattini-IR (PGIR) is a wide-field, synoptic infrared time domain survey covering ≈15,000 sq. deg. of the accessible sky at ≈1–3 night cadence to a depth ofJ≈ 13.0 and ≈14.9 Vega mag in and outside the Galactic plane, respectively. Here, we present the first data release ofJ-band light curves of Two Micron All Sky Survey (2MASS) sources within the survey footprint covering approximately the first four years of operations. We describe the construction of the source catalog based on 2MASS point sources, followed by exposure filtering criteria and forced PSF photometry. The catalog contains light curves of ≈286 million unique sources with 2MASS magnitudes ofJ< 15.5 mag, with a total of ≈50 billion photometric measurements and ≈20 billion individual source detections at signal-to-noise-ratio > 3. We demonstrate the photometric fidelity of the catalog by (i) quantifying the magnitude-dependent accuracy and uncertainty of the photometry with respect to 2MASS and (ii) comparing against forced PGIR aperture photometry for known variable sources. We present simple filtering criteria for selecting reliable photometric measurements as well as examplePythonnotebooks for users. This catalog is one of the largest compilation of nightly cadence, synoptic infrared light curves to date, comparable to those in the largest optical surveys, providing a stepping stone to upcoming infrared surveys in the coming decade.  more » « less
Award ID(s):
1816100
PAR ID:
10549214
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Publications of the Astronomical Society of the Pacific
Date Published:
Journal Name:
Publications of the Astronomical Society of the Pacific
Volume:
136
Issue:
10
ISSN:
0004-6280
Page Range / eLocation ID:
104501
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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