Presentation #232.01 in the session Supernovae II.
We present early results from the Young Supernova Experiment (YSE), an optical time-domain survey on the Pan-STARRS telescopes. Our survey is designed to obtain well-sampled griz light curves for thousands of transient events up to z ≍ 0.2 and tens of thousands of variable sources. This large sample of transients with four-band light curves will lay the foundation for the Vera C. Rubin Observatory and the Nancy Grace Roman Space Telescope, providing a critical training set in similar filters and a well-calibrated low-redshift anchor of cosmologically useful SNe Ia to benefit dark energy science. As the name suggests, YSE complements and extends other ongoing time-domain surveys by discovering fast-rising SNe within a few hours to days of explosion. YSE is the only current four-band time-domain survey and is able to discover transients as faint as ~21.5 mag in gri and ~20.5 mag in z, depths that allow us to probe the earliest epochs of stellar explosions. Stacked images from combined YSE and public PS1 observations will reach griz depths of 23.6, 23.7, 23.6, and 22.8 mag over ~5000 deg2 of sky. To date, YSE has discovered or observed more than 2500 transients, and ~5% of the transient candidates reported to the International Astronomical Union in 2020-2021. YSE’s follow-up spectroscopy and multi-wavelength light curves, including supplemental photometry from a long-term DECam survey, are forming a rich data set that will improve our understanding of the time-domain universe.