IW Andromedae

Source: Wikipedia, the free encyclopedia.
IW Andromedae

A visual band light curve for IW Andromedae, plotted from AAVSO data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Andromeda
Right ascension 01h 01m 08.907s[2]
Declination 43° 23′ 25.79″[2]
Apparent magnitude (V) 13.7 to 17.3[3]
Characteristics
Spectral type sdOB[4]
Variable type
Z Cam(?)[3]
Distance
2,860 ± 80 ly
(880 ± 30 pc)
Details
White dwarf
Mass0.75[5] M☉
Radius0.015[5] R☉
Temperature25,000[5] K
Donor star
Mass0.27[5] M☉
IW And, 2MASS J01010890+4323257, AAVSO 0055+42[6]
Database references
SIMBADdata

IW Andromedae is a

light years from the Sun based on parallax measurements.[2]

The irregular variability of this star was discovered by

hydrogen–alpha line was discovered by W. Liu and associates in 1999.[9]

This is a close binary system with an

mass of the Sun. The secondary component has 27% of the Sun's mass and is overflowing its Roche lobe, resulting in mass transfer to an accretion disk orbiting the primary. The accretion rate for the primary is 3×10−9 M☉·yr−1.[5]

T. Kato and associates in 2003 found the light curve matched a Z Cam variable, with the previously observed inactive states being caused by a characteristic standstill. The duty cycle of its standstill is unusually long for a variable of this class.[10] Outbursts during these standstills may be explained by flares on the secondary, which result in brief surges in mass transfer.[12]

Other variables displaying IW And–type behavior have since been discovered, including HO Puppis,[13] BC Cassiopeiae,[14] IM Eridani, V507 Cygni, and FY Vulpecula.[7]

References

  1. ^ "Download Data", aavso.org, AAVSO, retrieved 9 April 2023.
  2. ^
    doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR
    .
  3. ^
    S2CID 125853869
    .
  4. Bibcode:1980IBVS.1795....1M
    .
  5. ^
    S2CID 118631716
    .
  6. ^ "IW ANd". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-04-07.
  7. ^
    doi:10.1093/pasj/psy138
    , 20.
  8. Bibcode:1975MitVS...7....1M
    .
  9. ^
    S2CID 122899189
    .
  10. ^
    Bibcode:2003IBVS.5376....1K
    .
  11. Bibcode:1987IBVS.3081....1M
    .
  12. S2CID 119238557
    , A48.
  13. S2CID 231979353
    , 51.
  14. doi:10.1093/pasj/psaa096
    , 98.
Retrieved from "https://en.wikipedia.org/w/index.php?title=IW_Andromedae&oldid=1174834248"