omi Cet
CONFIRMED
MILKY WAY
Constellation
Cetus |
Equatorial coordinates
α = 02 19 20.792
δ = -02 58 39.496 |
Galactic coordinates
l = 167.7563°
b = -57.9835° |
Suspected |
1957Ref |
Confirmed |
2010Ref |
Symbiotic IR type |
DRef |
Hot component type |
accreting-onlyRef |
Outbursts |
- |
|
|
Symbiotic Catalogs
Bidelman (1954) |
- |
Allen (1984) |
- |
Belzcyński et al. (2001) |
o Ceti (Conf.) |
Gaposchkin (1957) |
o Cet (Conf.) |
Kenyon (1986) |
- |
Akras et al. (2019) |
o Ceti (Conf.) |
Boyarchuk (1969) |
- |
Vaidis (1988, 1991) |
- |
Position
Right ascension (°) |
34.8366Ref |
Parallax (mas) |
- |
Reddening E(B-V) (mag) |
0.02±0.0Ref, Note |
Declination (°) |
-2.9776Ref |
Distance (kpc) |
0.092±0.01Ref, 0.11Ref -, Note |
|
|
Galactic longitude (°) |
167.7563Ref |
Proper motion in α (mas/yr) |
- |
|
|
Galactic latitude (°) |
-57.9835Ref |
Proper motion in δ (mas/yr) |
- |
|
|
Observations
X-Ray |
YesRef |
IR type |
DRef |
Radio |
YesRef |
X-Ray type |
βRef |
J (mag) |
-0.73Ref |
Flickering |
YesRef |
GALEX FUV (mag) |
15.20Ref |
H (mag) |
-1.57Ref |
Outbursts |
- |
GALEX NUV (mag) |
12.93Ref |
K (mag) |
-2.21Ref |
Outburst type |
- |
IUE |
YesRef |
WISE W1 (mag) |
4.75Ref |
Jets |
- |
FUSE |
YesRef |
WISE W2 (mag) |
3.36Ref |
Resolved nebula |
NoRef |
U (mag) |
- |
WISE W3 (mag) |
0.10Ref |
IPmax (eV) |
54.4 (UV)Ref |
B (mag) |
7.67Ref |
WISE W4 (mag) |
-3.69Ref |
[O III] lines |
NoRef |
V (mag) |
6.74Ref |
IRAS 12μm (Jy) |
4880.00Ref |
He II lines |
NoRef |
R (mag) |
5.03Ref |
IRAS 25μm (Jy) |
2260.00Ref |
[Fe VII] lines |
NoRef |
I (mag) |
- |
IRAS 60μm (Jy) |
301.00Ref |
O VI lines |
NoRef |
BP (mag) |
- |
IRAS 100μm (Jy) |
88.40Ref |
|
|
G (mag) |
- |
AKARI S09 (Jy) |
- |
|
|
RP (mag) |
- |
AKARI S18 (Jy) |
- |
|
|
Orbit
Orbital period (days) |
181857.975Ref |
γ velocity (km/h) |
- |
Size of giant’s orbit (AU) |
- |
Eccentricity |
0.16±nanRef |
RV of giant (km/h) |
- |
Separation (AU) |
70Ref |
Inclination (°) |
112Ref |
Inferior conj. of giant (JD) |
- |
Mass function |
- |
Eclipses |
- |
|
|
Mass ratio |
2.85Ref |
Orbital ephemeris |
- |
|
|
|
|
Cool component
Spectral type |
M5-9 IIIRef |
Mass (M⊙) |
2Ref |
Pulsation |
YesRef |
Eff. temperature (K) |
2918-3192Ref |
Radius (R⊙) |
332-402Ref |
Type |
MiraRef |
IR type |
DRef |
Luminosity (L⊙) |
8400-9360Ref |
Pulsation period (days) |
333.09±0.04Ref |
Metallicity [Fe/H] |
-0.15±0.18Ref |
|
|
Pulsation ephemeris |
Max (V) = 2444839 + 333.09±0.04 x ERef |
Hot component
Type/Spectral type |
WDRef |
Mass (M⊙) |
0.6Ref, 0.7Ref |
Spin period (min) |
- |
Shell-burning/Accreting-only |
accreting-onlyRef |
Radius (R⊙) |
0.012Ref |
Accretion disk |
- |
Eff. temperature (K) |
10000-20000Ref |
Luminosity (L⊙) |
- |
|
|
Lower limit (K) |
- |
|
|
|
|
Upper limit (K) |
- |
|
|
|
|
Notes
The nature of omi Cet was debated in the literature for a long time. Kenyon & Webbink (1984) listed the object as an extreme example of the symbiotic phenomenon. Nowadays, the system is considered to be an accreting-only symbiotic star consisting of a Mira pulsator and a WD (resolved at several wavelengths; Karovska, 2006) on an orbit with an orbital period of 497.9 years (Prieur et al., 2002). It was detected in X-ray outburst by Karovska et al. (2005). Many aspects have been well-reviewed in the Introduction of the paper by Nhung et al. (2022).
References
- Karovska, M., Hack, W., Raymond, J. et al., 1997, ApJL, 482, 2, L175, 1997ApJ...482L.175K
- Karovska, M., Schlegel, E., Hack, W. et al., 2005, ApJL, 623, 2, L137, 2005ApJ...623L.137K
- Karovska, M., 2006, The X-ray Universe 2005, 604, 183, 2006ESASP.604..183K
- Kastner, J. H., Soker, N., 2004, ApJ, 616, 2, 1188, 2004ApJ...616.1188K
- Kenyon, S. J., Webbink, R. F., 1984, ApJ, 279, 252, 1984ApJ...279..252K
- Nhung, P. T., Hoai, D. T., Tuan-Anh, P. et al., 2022, ApJ, 927, 2, 169, 2022ApJ...927..169N
- Prieur, J. L., Aristidi, E., Lopez, B. et al., 2002, ApJS, 139, 1, 249, 2002ApJS..139..249P
- Sokoloski, J. L., Bildsten, L., 2010, ApJ, 723, 2, 1188, 2010ApJ...723.1188S
- Templeton, M. R., Karovska, M., 2009, ApJ, 691, 2, 1470, 2009ApJ...691.1470T
- Woodruff, H. C., Eberhardt, M., Driebe, T. et al., 2004, A&A, 421, 703, 2004A&A...421..703W
- Zamanov, R. K., Boeva, S., Spassov, B. et al., 2019, BlgAJ, 31, 110, 2019BlgAJ..31..110Z
Last updated: April 14, 2022