V4743 Sagittarii
Location of V4743 Sagittarii (circled in red)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Sagittarius
Right ascension 19h 01m 09.38s[1]
Declination −22° 00′ 05.9″[1]
Apparent magnitude (V) 5.0 – 16.8[2]
Characteristics
Variable type CN[3]
Astrometry
Distance~21,000[4] ly
(6,300 pc)
Details
Mass1.22[5] M☉
Other designations
Nova Sagittarii 2002 c, V4743 Sgr, AAVSO 1855-22[6]
Database references
SIMBADdata
The light curve of V4743 Sagittarii from AAVSO data

V4743 Sagittarii was a bright nova in the southern constellation of Sagittarius. This event was discovered by K. Haseda and colleagues in September 2002.[1] It peaked at magnitude 5.0[7] on September 20, 2002, then declined rapidly thereafter. It reached a peak temperature of 740,000 K around April 2003 and remained at that level for at least five months, suggesting the white dwarf component has a mass of 1.1–1.2 M☉.[8] The distance to this system is uncertain.[3] Infrared observations indicate a distance of approximately 21 kly (6.3 kpc).[4] A derivation using maximum magnitude rate of decay showed a distance of 12.7 ± 1.0 kly (3.9 ± 0.3 kpc).[8]

Observations of the nova by the Chandra X-ray Observatory taken 180 days after the event showed an amplitude variation with a period of about 22 minutes. The X-ray output was dropping rapidly, and changed from a continuous spectrum to one showing emission lines. X-ray light curves of this system show a periodic signal with a frequency of 0.75 MHz that suggests a rapidly rotating magnetic white dwarf in an intermediate polar system.[9][8] In 2003, an optical variation of 6.74 ± 0.07 hours was observed, and was interpreted as the orbital period of the binary system.[4] A proposed beat period of ~24 minutes has been detected in the optical in between the orbital and period cycles.[3]

References

  1. ^ a b c Haseda, K.; et al. (September 2002). "Another nova in Sagittarius". IAU Circular. 7975: 1. Bibcode:2002IAUC.7975....1H.
  2. ^ Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869.
  3. ^ a b c Zemko, P.; et al. (November 2018). "Optical observations of 'hot' novae returning to quiescence". Monthly Notices of the Royal Astronomical Society. 480 (4): 4489–4504. arXiv:1807.10321. Bibcode:2018MNRAS.480.4489Z. doi:10.1093/mnras/sty2061.
  4. ^ a b c Leibowitz, E.; et al. (September 2006). "Variability and multiperiodic oscillations in the X-ray light curve of the classical nova V4743 Sgr". Monthly Notices of the Royal Astronomical Society. 371 (1): 424–430. arXiv:astro-ph/0607157. Bibcode:2006MNRAS.371..424L. doi:10.1111/j.1365-2966.2006.10684.x. S2CID 17107776.
  5. ^ Shara, Michael M.; et al. (June 2018). "The Masses and Accretion Rates of White Dwarfs in Classical and Recurrent Novae". The Astrophysical Journal. 860 (2): 11. arXiv:1804.06880. Bibcode:2018ApJ...860..110S. doi:10.3847/1538-4357/aabfbd. S2CID 55851634. 110.
  6. ^ "V4743 Sgr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-12-01.
  7. ^ Watson, Christopher. "VSX : Detail for V4743 Sgr". aavso.org. Retrieved 2016-12-08.
  8. ^ a b c Zemko, P.; et al. (August 2016). "V4743 Sgr, a magnetic nova?". Monthly Notices of the Royal Astronomical Society. 460 (3): 2744–2751. arXiv:1606.00225. Bibcode:2016MNRAS.460.2744Z. doi:10.1093/mnras/stw1199.
  9. ^ Dobrotka, A.; Ness, J. -U. (June 2017). "Counter-evidence against multiple frequency nature of 0.75 mHz oscillation in V4743 Sgr". Monthly Notices of the Royal Astronomical Society. 467 (4): 4865–4871. arXiv:1702.05375. Bibcode:2017MNRAS.467.4865D. doi:10.1093/mnras/stx442.
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