TY - JOUR

T1 - Multiwavelength observations of the 2015 nova in the Local Group irregular dwarf galaxy IC 1613

AU - Williams, S. C.

AU - Darnley, M. J.

AU - Henze, M.

N1 - This is a pre-copy-editing, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The definitive publisher-authenticated version S. C. Williams, M. J. Darnley, M. Henze; Multiwavelength observations of the 2015 nova in the Local Group irregular dwarf galaxy IC 1613, Monthly Notices of the Royal Astronomical Society, Volume 472, Issue 2, 1 December 2017, Pages 1300–1314, https://doi.org/10.1093/mnras/stx1793 which is available online at: https://academic.oup.com/mnras/article/472/2/1300/4036873/Multiwavelength-observations-of-the-2015-nova-in

PY - 2017/12/1

Y1 - 2017/12/1

N2 - A nova in the Local Group irregular dwarf galaxy IC 1613 was discovered on 2015 September 10 and is the first nova in that galaxy to be spectroscopically confirmed. We conducted a detailed multi-wavelength observing campaign of the eruption with the Liverpool Telescope, the LCO 2m telescope at Siding Spring Observatory, and Swift, the results of which we present here. The nova peaked at $M_V=-7.93\pm0.08$ and was fast-fading, with decline times of $t_{2(V)}=13\pm2$ and $t_{3(V)}=26\pm2$ days. The overall light curve decline was relatively smooth, as often seen in fast-fading novae. Swift observations spanned 40 days to 332 days post-discovery, but no X-ray source was detected. Optical spectra show the nova to be a member of the hybrid spectroscopic class, simultaneously showing Fe II and N II lines of similar strength during the early decline phase. The spectra cover the eruption from the early optically thick phase, through the early decline and into the nebular phase. The H$\gamma$ absorption minimum from the optically thick spectrum indicates an expansion velocity of $1200\pm200$ km s$^{-1}$. The FWHM of the H$\alpha$ emission line between 10.54 and 57.51 days post-discovery shows no significant evolution and remains at $\sim1750$ km s$^{-1}$, although the morphology of this line does show some evolution. The nova appears close to a faint stellar source in archival imaging, however we find the most likely explanation for this is simply a chance alignment.

AB - A nova in the Local Group irregular dwarf galaxy IC 1613 was discovered on 2015 September 10 and is the first nova in that galaxy to be spectroscopically confirmed. We conducted a detailed multi-wavelength observing campaign of the eruption with the Liverpool Telescope, the LCO 2m telescope at Siding Spring Observatory, and Swift, the results of which we present here. The nova peaked at $M_V=-7.93\pm0.08$ and was fast-fading, with decline times of $t_{2(V)}=13\pm2$ and $t_{3(V)}=26\pm2$ days. The overall light curve decline was relatively smooth, as often seen in fast-fading novae. Swift observations spanned 40 days to 332 days post-discovery, but no X-ray source was detected. Optical spectra show the nova to be a member of the hybrid spectroscopic class, simultaneously showing Fe II and N II lines of similar strength during the early decline phase. The spectra cover the eruption from the early optically thick phase, through the early decline and into the nebular phase. The H$\gamma$ absorption minimum from the optically thick spectrum indicates an expansion velocity of $1200\pm200$ km s$^{-1}$. The FWHM of the H$\alpha$ emission line between 10.54 and 57.51 days post-discovery shows no significant evolution and remains at $\sim1750$ km s$^{-1}$, although the morphology of this line does show some evolution. The nova appears close to a faint stellar source in archival imaging, however we find the most likely explanation for this is simply a chance alignment.

KW - astro-ph.SR

KW - novae, cataclysmic variables

KW - stars: individual (Nova IC 1613 2015)

KW - ultraviolet: stars

U2 - 10.1093/mnras/stx1793

DO - 10.1093/mnras/stx1793

M3 - Journal article

VL - 472

SP - 1300

EP - 1314

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 2

ER -