Discovery of a Rapid, Luminous Nova in NGC 300 by the KMTNet Supernova Program

Antoniadis, John; Moon, D. S.; Ni, Yuan Qi; Kim, Dong-Jin; Lee, Yongseok; Neilson, Hilding R.

doi:10.3847/1538-4357/aa706b

Cited by 6 publications

(5 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We are conducting a systematic study of dwarf galaxies in nearby galaxy groups using data from the KMTNet (Korea Microlensing Telescope Network) Supernova Program (KSP; Moon et al 2016). KSP is a program to search for supernovae and optical transients (He et al 2016;Antoniadis et al 2017;Brown et al 2018;Lee et al 2019;Afsariardchi et al 2019) using three 1.6-m telescopes located at the Cerro Tololo Inter-American Observatory (CTIO, Chile), the South African Astronomical Observatory (SAAO, South Africa), and the Siding Spring Observatory (SSO, Australia). When several hundred KSP images in each field are stacked, the program provides deep BV I images reaching a sensitivity of about 28 mag arcsec −2 within a 1.5 acrsec radius aperture.…”

Section: Introductionmentioning

confidence: 99%

Dwarf Galaxy Discoveries from the KMTNet Supernova Program. II. The NGC 3585 Group and Its Dynamical State*

Park

Moon

Zaritsky

et al. 2019

ApJ

Self Cite

View full text Add to dashboard Cite

We present our discovery and analysis of dwarf galaxies in the NGC 3585 galaxy group by the KMTNet Supernova Program. Using deep stack images reaching ≃ 28 mag arcsec −2 in BV I, we discovered 46 dwarf galaxy candidates distributed in a 7 square degree field. The dwarf galaxy candidates exhibit central surface brightness as faint as µ 0,V = 26.2 mag arcsec −2 , with effective radii larger than 150 pc and total absolute magnitudes brighter than M V ≈ −10 mag, if at the distance of NGC 3585. The dwarf galaxy surface number density decreases with projected distance from NGC 3585. We estimate the background contamination to be about 20% based both on the number density profile and on diffuse galaxy counts in a control field. The dwarf galaxy colors and Sérsic structural parameters are consistent with those found for other dwarf galaxies. Unusually, there is no indication of a change of color or brightness in the dwarf galaxy candidates with projected distance from the group center. Approximately 20% of them contain an unresolved nucleus. The nucleated fraction is larger for brighter (and redder) galaxies but is independent of distance from the group center. We identify four ultra-diffuse galaxy candidates, all near the group center. We interpret these

show abstract

Section: Introductionmentioning

confidence: 99%

Dwarf Galaxy Discoveries from the KMTNet Supernova Program. II. The NGC 3585 Group and Its Dynamical State*

Park

Moon

Zaritsky

et al. 2019

ApJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, the origin of the color evolution is unknown. We also note that such color evolution is observed in the classical nova, where they suggest that the formation of a dust shell may have an additional thermal emission component, although how a dust shell can be formed is not explained (Antoniadis et al 2017). Here, for KSP-OT-201611a, the color evolution during the normal outburst may be explained if there is new cold material accreted from the secondary at the outer part of the accretion disk, increasing the flux in the I-band while overall temperature of the accretion disk increases during the outburst (Osaki 1989).…”

Section: Outburstsmentioning

confidence: 80%

KSP-OT-201611a: A Distant Population II Dwarf Nova Candidate Discovered by the KMTNet Supernova Program

Lee

Moon

Kim

et al. 2019

ApJ

Self Cite

View full text Add to dashboard Cite

We present a multi-color, high-cadence photometric study of a distant dwarf nova KSP-OT-201611a discovered by the Korea Microlensing Telescope Network Supernova Program. From October 2016 to May 2017, two outbursts, which comprises a super/long outburst followed by a normal/short outburst separated by ∼91 days, were detected in the BV I bands. The shapes and amplitudes of the outbursts reveal the nature of KSP-OT-201611a to be an SU UMa-or U Gem-type dwarf nova. Color variations of periodic humps in the super/long outbutst possibly indicate that KSP-OT-201611a is an SU UMatype dwarf nova. The super and normal outbursts show distinctively different color evolutions during the outbursts due most likely to the difference of time when the cooling wave is formed in the accretion disk. The outburst peak magnitudes and the orbital period of the dwarf nova indicate that it is at a large Galactocentric distance (∼13.8 kpc) and height (∼1.7 kpc) from the Galactic plane. KSP-OT-201611a, therefore, may provide a rare opportunity to study the accretion disk process of Population II dwarf novae.

show abstract

“…All our images are 60 sec exposures reaching an average detection limit of 21.5 mag. In addition to infant/early supernovae, KSP has also discovered other types of optical transients, including several novae and dwarf novae of interest (Antoniadis et al 2017;Brown et al 2018;Lee et al 2019Lee et al , 2022.…”

Section: Ksp-ot-201712a: Discovery and Light Curvesmentioning

confidence: 99%

Helium-deficient ER UMa-type Dwarf Nova below the Period Minimum with a Hot Secondary

Lee,

Moon,

Kim

et al. 2024

ApJ

Self Cite

View full text Add to dashboard Cite

We present the discovery of a peculiar dwarf nova KSP-OT-201712a using high-cadence, multicolor observations made with the Korea Microlensing Telescope Network. KSP-OT-201712a exhibits a rare presence of outbursts during standstills, as well as strong Hα emission for a dwarf nova below the period minimum with an orbital period of 58.75 ± 0.02 minutes. The outburst cycles are ∼6.6 days within standstills but increase to ∼15 days outside of them. Both B − V and V − I colors become bluer and redder as the outburst luminosities increase and decrease, respectively, for the outburst within standstill, while they evolve in the opposite directions outside of the standstills. The presence of strong double-peaked Hα and weak He i emission lines with He/H flux ratio of 0.27, together with absorption lines of Mg b and Na D in the source, leads to the estimation T eff ≃ 4570 ± 40 K, [Fe/H] ≃ 0.06 ± 0.15 dex, and log g ≃ 4.5 ± 0.1 for its secondary. KSP-OT-201712a is the second He-deficient dwarf nova below the period minimum, while the temperature of the secondary is measured for the first time in such objects. We identify it to be an ER UMa-type dwarf nova, suggesting that the evolution of dwarf novae across the period minimum is accompanied by large mass transfers. The high temperature of the secondary indicates that the system started its mass transfer when the secondary was about 93% of its main-sequence age. The system will evolve to a helium cataclysmic variable or to AM CVn once its hydrogen envelope is exhausted before it explodes as a Type Ia supernova.

show abstract

Discovery of a Rapid, Luminous Nova in NGC 300 by the KMTNet Supernova Program

Cited by 6 publications

References 37 publications

Dwarf Galaxy Discoveries from the KMTNet Supernova Program. II. The NGC 3585 Group and Its Dynamical State*

Dwarf Galaxy Discoveries from the KMTNet Supernova Program. II. The NGC 3585 Group and Its Dynamical State*

KSP-OT-201611a: A Distant Population II Dwarf Nova Candidate Discovered by the KMTNet Supernova Program

Helium-deficient ER UMa-type Dwarf Nova below the Period Minimum with a Hot Secondary

Contact Info

Product

Resources

About