The Young Supernova Experiment : Survey Goals, Overview, and Operations

Foley, R. J. and Narayan, G. and Hjorth, J. and Huber, M. E. and Aleo, P. D. and Angus, C. R. and Auchettl, K. and Baldassare, V. F. and Bruun, S. H. and Chambers, K. C. and Chatterjee, D. and Coppejans, D. L. and Coulter, D. A. and Demarchi, L. and Dimitriadis, G. and Drout, M. R. and Engel, A. and French, K. D. and Gagliano, A. and Gall, C. and Hung, T. and Izzo, L. and Jacobson-Galán, W. V. and Kilpatrick, C. D. and Korhonen, H. and Margutti, R. and Raimundo, S. I. and Ramirez-Ruiz, E. and Rest, A. and Rojas-Bravo, C. and Siebert, M. R. and Smartt, S. J. and Terreran, G. and Wojtak, R. and Agnello, A. and Ansari, Z. and Arendse, N. and Baldeschi, A. and Blanchard, P. K. and Brethauer, D. and Bright, J. S. and Boer, T. J.L.De and Fairlamb, J. R. and Grillo, C. and Hajela, A. and Hede, C. and Kolborg, A. N. and Law-Smith, J. A.P. and Magnier, E. A. and Malanchev, K. and Matthews, D. and Mockler, B. and Muthukrishna, D. and Pfister, H. and Ramanah, D. K. and Rest, S. and Sarangi, A. and Schr der, S. L. and Stauffer, C. and Stroh, M. C. and Taggart, K. L. and Tinyanont, S. and Wainscoat, R. J. (2021) The Young Supernova Experiment : Survey Goals, Overview, and Operations. Astrophysical Journal, 908 (2): 143. ISSN 0004-637X

Abstract

Time-domain science has undergone a revolution over the past decade, with tens of thousands of new supernovae (SNe) discovered each year. However, several observational domains, including SNe within days or hours of explosion and faint, red transients, are just beginning to be explored. Here we present the Young Supernova Experiment (YSE), a novel 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. 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. YSE is currently observing approximately 750 deg2 of sky every 3 days, and we plan to increase the area to 1500 deg2 in the near future. When operating at full capacity, survey simulations show that YSE will find ∼5000 new SNe per year and at least two SNe within 3 days of explosion per month. To date, YSE has discovered or observed 8.3% of the transient candidates reported to the International Astronomical Union in 2020. We present an overview of YSE, including science goals, survey characteristics, and a summary of our transient discoveries to date.