Bibliographic Details
| Title: |
Diversity in extinction laws of Type Ia supernovae measured between $0.2$ and $2\,\mu\mathrm{m}$ |
| Authors: |
Amanullah, R., Johansson, J., Goobar, A., Ferretti, R., Papadogiannakis, S., Petrushevska, T., Brown, P. J., Cao, Y., Contreras, C., Dahle, H., Elias-Rosa, N., Fynbo, J. P. U., Gorosabel, J., Guaita, L., Hangard, L., Howell, D. A., Hsiao, E. Y., Kankare, E., Kasliwal, M., Leloudas, G., Lundqvist, P., Mattila, S., Nugent, P., Phillips, M. M., Sandberg, A., Stanishev, V., Sullivan, M., Taddia, F., Östlin, G., Asadi, S., Herrero-Illana, R., Jensen, J. J., Karhunen, K., Lazarevi, S., Varenius, E., Santos, P., Sridhar, S. Seethapuram, Wallström, S. H. J., Wiegert, J. |
| Publication Year: |
2015 |
| Collection: |
Astrophysics |
| Subject Terms: |
Astrophysics - High Energy Astrophysical Phenomena |
| More Details: |
We present ultraviolet (UV) observations of six nearby Type~Ia supernovae (SNe~Ia) obtained with the Hubble Space Telescope, three of which were also observed in the near-IR (NIR) with Wide-Field Camera~3. UV observations with the Swift satellite, as well as ground-based optical and near-infrared data provide complementary information. The combined data-set covers the wavelength range $0.2$--$2~\mu$m. By also including archival data of SN 2014J, we analyse a sample spanning observed colour excesses up to $E(B-V)=1.4~$mag. We study the wavelength dependent extinction of each individual SN and find a diversity of reddening laws when characterised by the total-to-selective extinction $R_V$. In particular, we note that for the two SNe with $E(B-V)\gtrsim1~$mag, for which the colour excess is dominated by dust extinction, we find $R_V=1.4\pm0.1$ and $R_V=2.8\pm0.1$. Adding UV photometry reduces the uncertainty of fitted $R_V$ by $\sim50\,$% allowing us to also measure $R_V$ of individual low-extinction objects which point to a similar diversity, currently not accounted for in the analyses when SNe~Ia are used for studying the expansion history of the universe.
Comment: 31 pages, 28 figures, accepted for publication in MNRAS |
| Document Type: |
Working Paper |
| DOI: |
10.1093/mnras/stv1505 |
| Access URL: |
http://arxiv.org/abs/1504.02101 |
| Accession Number: |
edsarx.1504.02101 |
| Database: |
arXiv |
