Abstract
Because polarization encodes geometrical information about unresolved scattering regions, it provides a unique tool for analyzing the 3-D structures of supernovae (SNe) and their surroundings. SNe of all types exhibit time-dependent spectropolarimetric signatures produced primarily by electron scattering. These signatures reveal physical phenomena such as complex velocity structures, changing illumination patterns, and asymmetric morphologies within the ejecta and surrounding material. Interpreting changes in polarization over time yields unprecedentedly detailed information about supernovae, their progenitors, and their evolution. Begun in 2012, the SNSPOL Project continues to amass the largest database of time-dependent spectropolarimetric data on SNe. I present an overview of the project and its recent results. In the future, combining such data with interpretive radiative transfer models will further constrain explosion mechanisms and processes that shape SN ejecta, uncover new relationships among SN types, and probe the properties of progenitor winds and circumstellar material.
| Original language | English |
|---|---|
| Pages (from-to) | 54-58 |
| Number of pages | 5 |
| Journal | Proceedings of the International Astronomical Union |
| Volume | 12 |
| Issue number | S329 |
| DOIs | |
| State | Published - Nov 1 2016 |
| Externally published | Yes |
Funding
Begun in 2012 and funded by the National Science Foundation, the SNSPOL Project (PI: G.G. Williams) continues to amass the largest database of time-dependent spectropo-larimetric data on supernovae of all types. The SNSPOL Project obtains observations of bright SNe roughly once per month using the CCD Imaging/Spectropolarimeter (SPOL; Schmidt, Elston, & Lupie 1992) at either the 61” Kuiper telescope on Mt. Bigelow, the 2.3-m Bok on Kitt Peak, or the 6.5-m MMT on Mt. Hopkins. Supporting observations include optical and near-IR photometry from the Mount Laguna Observatory (Khandrika et al. 2014) and ISP probe star observations from the HPOL spectropolarimeter at the University of Toledo’s Ritter Observatory (Davidson et al. 2014). To date, the SNSPOL project has obtained spectropolarimetric data for over 80 SNe, of which 59 have been observed at more than one observational epoch. Acknowledgments. JLH and LNH thank the IAU for generous travel support. The SNSPOL Project is supported by NSF awards AST-1210599, AST-1210311, and AST-1210372; the SN 2009ip research was also partly funded by NSF award AST-1211916.
| Funders | Funder number |
|---|---|
| Mount Laguna Observatory | |
| University of Toledo’s Ritter Observatory | |
| National Science Foundation | AST-1210372, AST-1211916, AST-1210599, AST-1210311 |
| Islamic Azad University | |
| National Science Foundation | |
| ARC Centre of Excellence in Cognition and its Disorders |
Keywords
- astronomical databases:miscellaneous
- polarization
- supernovae: general