TY - JOUR

T1 - AT 2017fvz: a nova in the dwarf irregular galaxy NGC 6822

AU - Healy, M. W.

AU - Darnley, M. J.

AU - Copperwheat, C. M.

AU - Filippenko, A. V.

AU - Henze, M.

AU - Hestenes, J. C.

AU - James, P. A.

AU - Page, K. L.

AU - Williams, S. C.

AU - Zheng, W.

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 M W Healy, M J Darnley, C M Copperwheat, A V Filippenko, M Henze, J C Hestenes, P A James, K L Page, S C Williams, W Zheng, AT 2017fvz: a nova in the dwarf irregular galaxy NGC 6822, Monthly Notices of the Royal Astronomical Society, Volume 486, Issue 3, July 2019, Pages 4334–4347, https://doi.org/10.1093/mnras/stz1108 is available online at: https://academic.oup.com/mnras/article/486/3/4334/5475125

PY - 2019/7/1

Y1 - 2019/7/1

N2 - A transient in the Local Group dwarf irregular galaxy NGC 6822 (Barnard's Galaxy) was discovered on 2017 August 2 and is only the second classical nova discovered in that galaxy. We conducted optical, near-ultraviolet, and X-ray follow-up observations of the eruption, the results of which we present here. This 'very fast' nova had a peak $V$-band magnitude in the range $-7.41>M_V>-8.33$ mag, with decline times of $t_{2,V} = 8.1 \pm 0.2$ d and $t_{3,V} = 15.2 \pm 0.3$ d. The early- and late-time spectra are consistent with an Fe II spectral class. The H$\alpha$ emission line initially has a full width at half-maximum intensity of $\sim 2400$ km s$^{-1}$ - a moderately fast ejecta velocity for the class. The H$\alpha$ line then narrows monotonically to $\sim1800$ km s$^{-1}$ by 70 d post-eruption. The lack of a pre-eruption coincident source in archival Hubble Space Telescope imaging implies that the donor is a main sequence, or possibly subgiant, star. The relatively low peak luminosity and rapid decline hint that AT 2017fvz may be a 'faint and fast' nova.

AB - A transient in the Local Group dwarf irregular galaxy NGC 6822 (Barnard's Galaxy) was discovered on 2017 August 2 and is only the second classical nova discovered in that galaxy. We conducted optical, near-ultraviolet, and X-ray follow-up observations of the eruption, the results of which we present here. This 'very fast' nova had a peak $V$-band magnitude in the range $-7.41>M_V>-8.33$ mag, with decline times of $t_{2,V} = 8.1 \pm 0.2$ d and $t_{3,V} = 15.2 \pm 0.3$ d. The early- and late-time spectra are consistent with an Fe II spectral class. The H$\alpha$ emission line initially has a full width at half-maximum intensity of $\sim 2400$ km s$^{-1}$ - a moderately fast ejecta velocity for the class. The H$\alpha$ line then narrows monotonically to $\sim1800$ km s$^{-1}$ by 70 d post-eruption. The lack of a pre-eruption coincident source in archival Hubble Space Telescope imaging implies that the donor is a main sequence, or possibly subgiant, star. The relatively low peak luminosity and rapid decline hint that AT 2017fvz may be a 'faint and fast' nova.

KW - astro-ph.SR

U2 - 10.1093/mnras/stz1108

DO - 10.1093/mnras/stz1108

M3 - Journal article

VL - 486

SP - 4334

EP - 4347

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 3

ER -