THE Pan-STARRS1 PHOTOMETRIC SYSTEM

TLDR

The Pan‑STARRS1 survey collects deep, multi‑epoch, multi‑color observations north of declination –30°, with photometric and astrometric calibration that makes the data a reference for many studies, and its photometric system is based on HST Calspec white‑dwarf models. This paper determines the Pan‑STARRS1 photometric system (gP1, rP1, iP1, zP1, yP1, wP1) by defining the magnitude system and measuring its passbands, including instrumental sensitivity and atmospheric transmission. The authors measure the system passbands, accounting for instrument sensitivity and atmospheric transmission, and discuss remaining systematic errors. They provide by‑products such as transformations to other photometric systems, Galactic extinction corrections, and the stellar locus.

Abstract

The Pan-STARRS1 survey is collecting multi-epoch, multi-color observations of the sky north of declination −30° to unprecedented depths. These data are being photometrically and astrometrically calibrated and will serve as a reference for many other purposes. In this paper, we present our determination of the Pan-STARRS1 photometric system: gP1, rP1, iP1, zP1, yP1, and wP1. The Pan-STARRS1 photometric system is fundamentally based on the Hubble Space Telescope Calspec spectrophotometric observations, which in turn are fundamentally based on models of white dwarf atmospheres. We define the Pan-STARRS1 magnitude system and describe in detail our measurement of the system passbands, including both the instrumental sensitivity and atmospheric transmission functions. By-products, including transformations to other photometric systems, Galactic extinction, and stellar locus, are also provided. We close with a discussion of remaining systematic errors.