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

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.

Testing the consistency of dust laws in SN Ia host galaxies: A BayeSN Examination of Foundation DR1

“…Future investigations into these scientific questions and the refinement of our statistical modelling and inference techniques will both be greatly enhanced by the growth of well-calibrated SN Ia datasets. In particular, future data releases from the Foundation Supernova Survey and the Young Supernova Experiment (YSE; Jones et al 2021) will increase the already large sample of low-SNe Ia with Pan-STARRS light curves. Complementing this, the Carnegie Supernova Project-II (CSP-II Phillips et al 2019) will augment the previous CSP-I data releases (Contreras et al 2010;Stritzinger et al 2011;Krisciunas et al 2017) to provide further high quality observations at 0.1.…”

“…From the landmark discovery of the Universe's accelerating expansion (Riess et al 1998;Perlmutter et al 1999), to state-of-the-art efforts measuring the Hubble constant (Dhawan et al 2018;Burns et al 2018;Riess et al 2019) and dark energy equation-of-state parameter (Scolnic et al 2018;Abbott et al 2019), Type Ia supernovae (SNe Ia) have been a key pillar in our understanding of cosmology. The ongoing development of a homogeneous low redshift SN Ia sample (Foley et al 2018;Jones et al 2019Jones et al , 2021, as well as future high redshift data from the Nancy Grace Roman Space Telescope (Spergel et al 2015;Hounsell et al 2018) and the Vera C. Rubin Observatory's Legacy Survey of Space and Time (Ivezić et al 2019), will enable a new era of precision cosmology. To make the most of the incoming data, however, SN Ia models must be improved, and subtleties such as SN-host correlations (e.g.…”

“…In the near future, the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST; Ivezić et al 2019), and supernova programs on the Nancy Grace Roman Space Telescope (Roman Space Telescope;Spergel et al 2015;Hounsell et al 2018), will massively expand the high-redshift SN Ia dataset which informs dark energy analyses. However, these projects are likely to yield small or suboptimal low redshift samples (Foley et al 2018;Hounsell et al 2018;Jones et al 2021), meaning these data must come from elsewhere. The low-redshift sample used in many previous analyses (e.g.…”

“…By following up SN Ia discoveries that mainly come from 'untargeted' surveys -primarily the All-Sky Automated Search for Supernovae (ASAS-SN; Shappee et al 2014) and Pan-STARRS Survey for Transients (PSST; Huber et al 2015) -this sample should be considerably less biased in terms of host galaxy properties than existing low redshift data. Future data releases of the Foundation program and the Young Supernova Experiment (YSE; Jones et al 2021) will enlarge this further. This will provide a homogeneous, well-calibrated low-SN Ia sample to anchor the LSST and Roman Space Telescope datasets of the future, and accompany the considerable high-sample already observed in the PS1 MDS (Rest et al 2014;Scolnic et al 2018;Villar et al 2020).…”

Two c’s in a pod: cosmology-independent measurement of the Type Ia supernova colour–luminosity relation with a sibling pair

“…Currently, ZTF has a few SN Ia siblings (see Graham et al, 2021, in prep), while data collection continues in phase II. DES has published a few siblings, and one can expect more siblings from large ongoing surveys like ZTF, Young Supernova Experiment (Jones et al 2021) and upcoming surveys like the Legacy Survey of Space and Time (LSST Science Collaboration et al 2009;Ivezić et al 2019) at the Vera C. Rubin Observatory. While a simple square root of N calculation would suggest that ∼ 10 sibling systems should tighten the constraints to competitive levels, this actually depends on the properties of the SN Ia themselves.…”