A remarkable recurrent nova in M 31: The X-ray observations

Henze, M.; Ness, J. U.; Darnley, M. J.; Bode, M. F.; Williams, S. C.; Shafter, A. W.; Kato, Mariko; Hachisu, Izumi

doi:10.1051/0004-6361/201423410

Cited by 51 publications

(90 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The ultra-short recurrence period nova M31N 2008-12a shows a supersoft X-ray source phase (SSS) of 10 days (Henze et al 2014aTang et al 2014). In general, the SSS phase (from E to F in Figure 1) is shorter for a more massive WD.…”

Section: X-ray Light Curvementioning

confidence: 96%

“…We carried out a coordinated, very high-cadence observing campaign with the Swift satellite (Gehrels et al 2004) to detect the X-ray flash during the 2015 outburst of the recurrent nova M31N 2008-12a (Darnley et al 2014(Darnley et al , 2015Henze et al 2014aHenze et al , 2015aTang et al 2014). This is the ideal object to detect X-ray flashes because its recurrence period is as short as a year, possibly even half a year (Henze et al 2015b).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

X-RAY FLASHES IN RECURRENT NOVAE: M31N 2008-12a AND THE IMPLICATIONS OF THE SWIFT NONDETECTION

Kato

Saio

Henze

et al. 2016

ApJ

View full text Add to dashboard Cite

Models of nova outbursts suggest that an X-ray flash should occur just after hydrogen ignition. However, this X-ray flash has never been observationally confirmed. We present four theoretical light curves of the X-ray flash for two very massive white dwarfs (WDs) of 1.380 and 1.385 M ⊙ and for two recurrence periods of 0.5 and 1 years. The duration of the X-ray flash is shorter for a more massive WD and for a longer recurrence period. The shortest duration of 14 hours (0.6 days) among the four cases is obtained for the 1.385 M ⊙ WD with one year recurrence period. In general, a nova explosion is relatively weak for a very short recurrence period, which results in a rather slow evolution toward the optical peak. This slow timescale and the predictability of very short recurrence period novae give us a chance to observe X-ray flashes of recurrent novae. In this context, we report the first attempt, using the Swift observatory, to detect an X-ray flash of the recurrent nova M31N 2008-12a (0.5 or 1 year recurrence period), which resulted in the non-detection of X-ray emission during the period of 8 days before the optical detection. We discuss the impact of these observations on nova outburst theory. The X-ray flash is one of the last frontiers of nova studies and its detection is essentially important to understand the pre-optical-maximum phase. We encourage further observations.

show abstract

Section: X-ray Light Curvementioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

X-RAY FLASHES IN RECURRENT NOVAE: M31N 2008-12a AND THE IMPLICATIONS OF THE SWIFT NONDETECTION

Kato

Saio

Henze

et al. 2016

ApJ

View full text Add to dashboard Cite

show abstract

“…From results of other surveys, we know that some number of such fast novae do exist, an example being the famous M 31N 2008-12a (Shafter et al 2012;Darnley et al 2014;Henze et al 2014;Tang et al 2014; see also the MPE optical nova catalog from footnote 3), but their true frequencies in the bulge and the disk of the galaxy remain to be determined.…”

Section: Fast Novaementioning

confidence: 99%

“…We used the light curves from the PTF (Cao et al 2012) and WeCAPP (Lee et al 2012) nova catalogs with morphological classification available, the light curves from Shafter et al (2011) that have been observed in the V-band, the highquality light curves from Capaccioli et al (1989), and the sample of extragalactic novae discovered by P60-FasTING (Kasliwal et al 2011). To this compilation, we added the recently discovered very fast recurrent nova M 31N 2008-12a in M 31 with the shortest known recurrence period of ∼1 yr (Shafter et al 2012;Darnley et al 2014;Henze et al 2014;Tang et al 2014). The PTF and WeCAPP light curves were converted from R-band to V-band using the color (V −R) • = 0.16 (Shafter et al 2009) after accounting for the foreground extinction of A R = 0.15 (Shafter et al 2009) estimated using a reddening of E(B − V) = 0.062 along the line of sight to M 31 from Schlegel et al (1998).…”

Section: Appendix B: Peak Magnitudes Of Novaementioning

confidence: 99%

Constraining the role of novae as progenitors of type Ia supernovae

Soraisam

Gilfanov

2015

A&A

View full text Add to dashboard Cite

Context. With the progenitors of type Ia supernovae (SNe Ia) still eluding direct detections, various types of accreting white dwarfs (WDs) have been proposed as prospective candidates. One of the possibilities are WDs undergoing unstable nuclear burning on their surfaces. Although observations and theoretical modeling of classical novae generally suggest that more material is ejected during the explosion than is accreted, there is growing evidence that in certain accretion regimes of novae, appreciable mass accumulation by the WD in the course of unstable nuclear burning may be possible. Aims. We propose that statistics of novae in nearby galaxies may be a powerful tool to determine the role these systems play in producing SNe Ia. Methods. We used multicycle nova evolutionary models to compute the number and temporal distribution of novae that would be produced by a typical SN Ia progenitor before it reached the Chandrasekhar mass limit (M ch ) and exploded, assuming that it experienced unstable nuclear burning during its entire accretion history. We then used the observed nova rate in M 31 to constrain the maximal contribution of the nova channel to the SN Ia rate in this galaxy. Results. The M 31 nova rate measured by the POINT-AGAPE survey is ≈65 yr −1 . Assuming that all these novae will reach M ch , we estimate the maximal SN Ia rate novae may produce, which is < ∼ 0.1-0.5 × 10 −3 yr −1 . This constrains the overall contribution of the nova channel to the SN Ia rate at < ∼ 2-7%. However, if all POINT-AGAPE novae do eventually reach M ch , a significant population of fast novae (t 2 < ∼ 10 days) originating from the most massive WDs is expected, with a rate of ∼200−300 yr −1 , which is significantly higher than currently observed. We point out that statistics of such fast novae can provide powerful diagnostics of the contribution of the nova channel to the final stage of mass accumulation by the single-degenerate (SD) SN Ia progenitors. To explore the prospects of their use, we investigated the efficiency of detecting fast novae as a function of the limiting magnitude and temporal sampling of a nova survey of M 31 by a PTF class telescope. We find that a survey with the limiting magnitude of m R ≈ 22 observing at least every second night will catch ≈90% of fast novae expected in the SD scenario. Such surveys should be detecting fast novae in M 31 at a rate on the order of > ∼ 10 3 × f per year, where f is the fraction of SNe Ia that accreted in the unstable nuclear burning regime while accumulating the final ΔM ≈ 0.1 M before the supernova explosion.

show abstract

“…In the previous paper (Kato et al 2017), we established an iteration method for calculating the extended stage of novae with time-dependent mass-loss rates of optically thick winds, and presented a model for one full cycle of a nova outburst for the recurrent nova M31N 2008-12a. M31N 2008-12a has exploded almost every year which makes this object as the shortest record of the recurrence period of P rec ∼ 1 yr (Darnley et al , 2016Henze et al 2014Henze et al , 2015aTang et al 2014;Darnley et al 2016) or P rec ∼ 0.5 yr.…”

Section: Introductionmentioning

confidence: 99%

A Millennium-long Evolution of the 1 yr Recurrence Period Nova—Search for Any Indication of the Forthcoming He Flash

Kato

Saio

Hachisu

2017

ApJ

View full text Add to dashboard Cite

We present 1500 cycles of hydrogen shell flashes on a 1.38 M ⊙ white dwarf (WD) for a mass accretion rate of 1.6 × 10 −7 M ⊙ yr −1 , the mass ejection of which is calculated consistently with the optically thick winds. This model mimics the one-year-recurrence-period nova M31N 2008-12a. Through these hydrogen flashes a helium ash layer grows in mass and eventually triggers a helium nova outburst. Each hydrogen flash is almost identical and there is no precursor for the forthcoming He flash either in the outburst or in the quiescent until the next He flash suddenly occurs. Thus, M31N 2008-12a is a promising candidate of He novae, outbursting in any time within a millennium years. The prompt X-ray flash of He nova lasts as short as 15 min with the X-ray luminosity being about a half of the Eddington luminosity, making the observation difficult. In the very early phase of a He flash, the uppermost H-rich layer is convectively mixed into the deep interior and most of hydrogen is consumed by nuclear burning. In comparison with hydrogen shell flashes of M31N 2008-12a, we expect the forthcoming He nova with a very short prompt X-ray flash (15 min), a very bright optical/NIR peak (∼ 3.5 mag brighter than M31N 2008-12a), a much longer nova duration (> 2 years), and a longer supersoft X-ray source phase (40-50 days or more).

show abstract

A remarkable recurrent nova in M 31: The X-ray observations

Cited by 51 publications

References 38 publications

X-RAY FLASHES IN RECURRENT NOVAE: M31N 2008-12a AND THE IMPLICATIONS OF THE SWIFT NONDETECTION

X-RAY FLASHES IN RECURRENT NOVAE: M31N 2008-12a AND THE IMPLICATIONS OF THE SWIFT NONDETECTION

Constraining the role of novae as progenitors of type Ia supernovae

A Millennium-long Evolution of the 1 yr Recurrence Period Nova—Search for Any Indication of the Forthcoming He Flash

Contact Info

Product

Resources

About