Princeton University Survey Science Discussion

Abstract 1. The Subaru Prime Focus Spectrograph (PFS) will soon be the first massively-multiplexed wide-field spectrograph on a 8-meter class telescope. PFS’s spectrograph system covers the optical to near-infrared—380 to 1260nm—in a single exposure and is fed by 2386 reconfigurable fibers distributed across a 1.3-degree wide field of view. Leveraging deep multiband imaging catalogs, particularly from Subaru’s Hyper Suprime-Cam (HSC) imager, PFS will fuel future discoveries in cosmology, galaxy evolution, and galactic archaeology. To fully leverage Subaru’s 8.2 meter aperture and probe the faintest targets, accurate spectral reduction and sky subtraction are critical to PFS’s operation. In commissioning of the PFS, the accuracy of the sky subtraction algorithms is being assessed through direct observations of the night sky. Here, we report the current status of the sky-subtraction routines, as determined from the commissioning data.

Abstract 2. The PFS pipeline is fundamentally dependent on understanding the emission of both atoms and molecules in the atmosphere, commonly grouped under the umbrella term of airglow. We have constructed a model for the airglow which has improved wavelength calibration greatly. The model is based on observations made with SuNSS, an auxiliary telescope dedicated to understanding the airglow, the results from which I will also discuss.