SN 2005hk was a peculiar Type Iax supernova event in UGC 272, which is a barred spiral galaxy[6] in the equatorial constellation of Cetus. This galaxy is located at a distance of approximately 185.1 million light-years (56.75 Mpc) from the Milky Way.[5] The supernova was discovered October 30, 2005.[7]
 Host galaxy UGC 272 imaged by Legacy Surveys | |
| Event type | Supernova |
|---|---|
| Type Iax[1] | |
| Date | October 30, 2005[2][3] |
| Instrument | SDSS[2] |
| Constellation | Cetus |
| Right ascension | 00h 27m 50.89s[4] |
| Declination | −01° 11′ 53.3″[4] |
| Epoch | J2000 |
| Distance | 185.1 Mly (56.75 Mpc)[5] |
| Redshift | 0.012993±0.000041[1] |
| Host | UGC 272[1] |
Observations
editThis event was discovered by J. Burket and W. Li on October 30, 2005. At magnitude 17.5, it was located 17.2″ east and 6.9″ north of the UGC 272 nucleus.[7] This supernova was independently discovered on images taken with the SDSS telescope dated October 28. The event was not observed on images taken two days earlier.[2]
The early spectra of SN 2005hk appeared peculiar, with prominent lines of double-ionized iron and only weak lines of intermediate mass elements. It was similar to SN 2002cx, with an unusually slow photospheric velocity of 6,000 km/s. These peculiarities could not be readily explained as the result of a large asymmetry in the explosion.[8] It was under-luminous for a Type Ia supernova, reaching peak light on November 9 with a near-normal spectrum for a supernova of this type. The later spectrum then continued to resemble SN 2002cx as it evolved.[3][9]
At later stages, this supernova did not show the nebular emission lines of a normal Type Ia supernova, instead showing iron and calcium lines.[10] It was suggested that the peculiarity of this event was due to a deflagration explosion.[11] However, observations with the Hubble Space Telescope showed no evidence of unburnt material at late stages, ruling out a "complete deflagration" model.[10] Type Iax supernovae such as SN 2005hk are now widely interpreted as a pure deflagration of a Chandrasekhar mass carbon-oxygen white dwarf. This explosion may have been insufficient to completely unbind the progenitor. Instead, it could have left behind a stellar remnant that is coated in the nuclear products of the explosion, including 56Ni.[12]
References
edit- 1 2 3 Friedman, Andrew S.; et al. (October 2004), "CfAIR2: Near-infrared Light Curves of 94 Type Ia Supernovae", The Astrophysical Journal, 613 (2): 1120–1132, arXiv:astro-ph/0105490, Bibcode:2004ApJ...613.1120G, doi:10.1086/422986.
- 1 2 3 Barentine, J.; et al. (November 2005), Green, D. W. E. (ed.), "Supernovae 2005hk-2005ik", Central Bureau Electronic Telegrams, 268: 1, Bibcode:2005CBET..268....1B.
- 1 2 Stanishev, V.; et al. (August 2007), "The Peculiar Type Ia Supernova 2005hk", The Multicolored Landscape of Compact Objects and their Explosive Origins, AIP Conference Proceedings, vol. 924, pp. 336–341, arXiv:astro-ph/0611354, Bibcode:2007AIPC..924..336S, doi:10.1063/1.2774878.
- 1 2 Zheng, Chen; et al. (May 2008), "First-Year Spectroscopy for the Sloan Digital Sky Survey-II Supernova Survey", The Astronomical Journal, 135 (5): 1766–1784, arXiv:0802.3220, Bibcode:2008AJ....135.1766Z, doi:10.1088/0004-6256/135/5/1766.
- 1 2 Tully, R. Brent; et al. (October 2013), "Cosmicflows-2: The Data", The Astronomical Journal, 146 (4): 25, arXiv:1307.7213, Bibcode:2013AJ....146...86T, doi:10.1088/0004-6256/146/4/86, S2CID 118494842, 86.
- ↑ Phillips, M. M.; et al. (April 2007), "The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations?", The Publications of the Astronomical Society of the Pacific, 119 (854): 360–387, arXiv:astro-ph/0611295, Bibcode:2007PASP..119..360P, doi:10.1086/518372.
- 1 2 Quimby, R.; et al. (October 31, 2005), Green, D. W. E. (ed.), "S/2005 P 1, S/2005 P 2; 2005hh, 2005hi, 2005hj, 2005hk", International Astronomical Union Circular, 8625: 1, retrieved 2026-03-23.
- ↑ Chornock, Ryan; et al. (May 2006), "Spectropolarimetry of the Peculiar Type Ia Supernova 2005hk", The Publications of the Astronomical Society of the Pacific, 118 (843): 722–732, arXiv:astro-ph/0603083, Bibcode:2006PASP..118..722C, doi:10.1086/504117.
- ↑ Sahu, D. K.; et al. (June 2008), "The Evolution of the Peculiar Type Ia Supernova SN 2005hk over 400 Days", The Astrophysical Journal, 680 (1): 580–592, arXiv:0710.3636, Bibcode:2008ApJ...680..580S, doi:10.1086/587772.
- 1 2 McCully, Curtis; et al. (May 2014), "Hubble Space Telescope and Ground-based Observations of the Type Iax Supernovae SN 2005hk and SN 2008A", The Astrophysical Journal, 786 (2), id. 134, arXiv:1309.4457, Bibcode:2014ApJ...786..134M, doi:10.1088/0004-637X/786/2/134.
- ↑ Maund, Justyn R.; et al. (October 2010), "A Spectropolarimetric View on the Nature of the Peculiar Type I SN 2005hk", The Astrophysical Journal, 722 (2): 1162–1174, arXiv:1008.3985, Bibcode:2010ApJ...722.1162M, doi:10.1088/0004-637X/722/2/1162.
- ↑ Callan, F. P.; et al. (May 2024), "Including a luminous central remnant in radiative transfer simulations for Type Iax supernovae", Monthly Notices of the Royal Astronomical Society, 530 (2): 1457–1473, arXiv:2403.15084, Bibcode:2024MNRAS.530.1457C, doi:10.1093/mnras/stae847.