T CrB

Constellation
Corona Borealis

Equatorial coordinates
α = 15 59 30.157
δ = +25 55 12.806

Galactic coordinates
l = 42.3739°
b = 48.1647°

Suspected	1932^Ref
Confirmed	1933^Ref
Symbiotic IR type	S^Ref
Hot component type	accreting-only^Ref
Outbursts	Yes^Ref - SyRN^Ref

Identifiers

T CrB	IRAS 15574+2603	GSC2.4.2 N64T000284	AAVSO 000-BBW-825
SIMBAD V* T CrB	Pan-STARRS 139102398753744451	SAO 84129	VSX 10602
GAIA DR3 1220110705972528512	SkyMapper -	WRAY -	GCVS T CrB
2MASS J15593015+2555126	HIP 78322	Hen -	BD +26 2765
WISE J155930.14+255512.6	TYC 2037-1144-1	ESO -	HD 143454

Symbiotic Catalogs

Bidelman (1954)	T Crb (Conf.)	Allen (1984)	T CrB (Conf.)	Belzcyński et al. (2001)	T CrB (Conf.)
Gaposchkin (1957)	-	Kenyon (1986)	T CrB (Conf.)	Akras et al. (2019)	T CrB (Conf.)
Boyarchuk (1969)	-	Vaidis (1988, 1991)	T CrB (Conf.)

Position

Right ascension (°)	239.8757^Ref	Parallax (mas)	1.092±0.028^Ref	Reddening E(B-V) (mag)	0.06±0.0^Ref ^{, Note}
Declination (°)	25.9202^Ref	Distance (kpc)	0.96±0.15^Ref 0.89^Ref ^{, Note}, 0.90^Ref ^{, Note}
Galactic longitude (°)	42.3739^Ref	Proper motion in α (mas/yr)	-4.46±0.02^Ref
Galactic latitude (°)	48.1647^Ref	Proper motion in δ (mas/yr)	12.02±0.03^Ref

Observations

X-Ray	Yes^Ref	IR type	S^Ref	Radio	Yes^Ref
X-Ray type	δ^Ref	J (mag)	6.00^Ref	Flickering	Yes^Ref
GALEX FUV (mag)	16.20^Ref	H (mag)	5.15^Ref	Outbursts	Yes^Ref
GALEX NUV (mag)	15.25^Ref	K (mag)	4.81^Ref	Outburst type	SyRN^Ref
IUE	Yes^Ref	WISE W1 (mag)	4.54^Ref	Jets	-
FUSE	No^Ref	WISE W2 (mag)	4.50^Ref	Resolved nebula	No^Ref
U (mag)	2.69^Ref	WISE W3 (mag)	4.41^Ref	IPmax (eV)	54.4^Ref, 77.5 (UV)^Ref
B (mag)	11.43^Ref	WISE W4 (mag)	4.23^Ref	[O III] lines	Yes^Ref
V (mag)	10.12^Ref	IRAS 12μm (Jy)	0.70^Ref	He II lines	Yes^Ref
R (mag)	9.70^Ref	IRAS 25μm (Jy)	0.23^Ref	[Fe VII] lines	No^Ref
I (mag)	-	IRAS 60μm (Jy)	0.40^Ref	O VI lines	No^Ref
BP (mag)	9.91^Ref	IRAS 100μm (Jy)	1.00^Ref
G (mag)	8.72^Ref	AKARI S09 (Jy)	0.95^Ref
RP (mag)	7.62^Ref	AKARI S18 (Jy)	0.25^Ref

Orbit

Orbital period (days)	227.53±0.02^Ref, 227.5687±0.0099^Ref	γ velocity (km/h)	-27.89±0.06^Ref, -27.79±0.13^Ref, -4.46±2.98^Ref	Size of giant’s orbit (AU)	0.488^Ref, 0.499^Ref
Eccentricity	0^Ref	RV of giant (km/h)	23.32±0.16^Ref, 23.89±0.17^Ref	Separation (AU)	-
Inclination (°)	60^Ref, 60±5^Ref, 68^Ref, 70^Ref	Inferior conj. of giant (JD)	2431933.83,2447918.62	Mass function	0.299^Ref, 0.3224^Ref
Eclipses	No^Ref			Mass ratio	1.3^Ref, 1^Ref, 0.6^Ref
Orbital ephemeris	-

Cool component

Spectral type	M3 III^Ref, M4.1 III^Ref, M4.5 III^Ref	Mass (M_⊙)	2.1^Ref, 1.4^Ref, 0.7±0.2^Ref, 1.38±0.2^Ref	Pulsation	Yes?^Ref
Eff. temperature (K)	3560^Ref, 3600^Ref	Radius (R_⊙)	90^Ref, 66±11^Ref	Type	-
IR type	S^Ref	Luminosity (L_⊙)	620±120^Ref	Pulsation period (days)	55^Ref
Metallicity [Fe/H]	0.02^Ref, 0.35±0.08^Ref			Pulsation ephemeris	-

Hot component

Type/Spectral type	WD^Ref	Mass (M_⊙)	1.4^Ref, 1.2^Ref, 1.35^Ref, 1.32^Ref	Spin period (min)	100-110?^Ref
Shell-burning/Accreting-only	accreting-only^Ref	Radius (R_⊙)	-	Accretion disk	-
Eff. temperature (K)	65800±2500^Ref	Luminosity (L_⊙)	40-70^Ref
Lower limit (K)	-
Upper limit (K)	-

Links

SIMBAD CDS Portal ARAS Database

Notes

A periodicity of 230.5 days was identified by Sanford (1949). In the outburst spectra, coronal emission lines such as [Fe X] and [Fe XIV] were observed by Bloch & Mao-Lin (1953). The activity of T CrB between SyRN outbursts was suggested to be similar to that in Z And-type stars by Iłkiewicz et al. (2016). Munari et al. (2016) presented spectra of T CrB in quiescence and super-active states. The next outburst of T CrB is predicted for 2026+-3 years (Luna et al., 2020). Furthermore, Iłkiewicz et al. (2023) proposed a close relation between T CrB and SU UMa-type dwarf novae.

References

Barnard, E. E., 1907, ApJ, 25, 279, 1907ApJ....25..279B
Belczyński, K., Mikołajewska, J., 1998, MNRAS, 296, 1, 77, 1998MNRAS.296...77B
Berman, L., 1932, PASP, 44, 261, 318, 1932PASP...44..318B
Bloch, M., Mao-Lin, T., 1953, AnAp, 16, 73, 1953AnAp...16...73B
Fekel, F. C., Joyce, R. R., Hinkle, K. H. et al., 2000, AJ, 119, 3, 1375, 2000AJ....119.1375F
Hachisu, I., Kato, M., 1999, ApJL, 517, 1, L47, 1999ApJ...517L..47H
Hric, L., Petrík, K., Urban, Z. et al., 1998, A&A, 339, 449, 1998A&A...339..449H
Iłkiewicz, K., Mikołajewska, J., Stoyanov, K. A., 2023, ApJL, 953, 1, L7, 2023ApJ...953L...7I
Iłkiewicz, K., Mikołajewska, J., Stoyanov, K. et al., 2016, MNRAS, 462, 3, 2695, 2016MNRAS.462.2695I
Kenyon, S. J., Garcia, M. R., 1986, AJ, 91, 125, 1986AJ.....91..125K
Kraft, R. P., 1958, ApJ, 127, 625, 1958ApJ...127..625K
Lines, H. C., Lines, R. D., Mcfaul, T. G., 1988, AJ, 95, 1505, 1988AJ.....95.1505L
Luna, G. J. M., Mukai, K., Sokoloski, J. L. et al., 2018, A&A, 619, A61, 2018A&A...619A..61L
Luna, G. J. M., Sokoloski, J. L., Mukai, K. et al., 2020, ApJL, 902, 1, L14, 2020ApJ...902L..14L
Luna, G. J. M., Sokoloski, J. L., Mukai, K., 2008, RS Ophiuchi (2006) and the Recurrent Nova Phenomenon, 401, 342, 2008ASPC..401..342L
Merrill, P. W., Burwell, C. G., 1933, ApJ, 78, 87, 1933ApJ....78...87M
Munari, U., Dallaporta, S., Cherini, G., 2016, NewA, 47, 7, 2016NewA...47....7M
Mürset, U., Schmid, H. M., 1999, A&AS, 137, 473, 1999A&AS..137..473M
Pavlenko, Y. V., Evans, A., Banerjee, D. P. K. et al., 2020, MNRAS, 498, 4, 4853, 2020MNRAS.498.4853P
Sanford, R. F., 1949, ApJ, 109, 81, 1949ApJ...109...81S
Selvelli, P. L., Cassatella, A., Gilmozzi, R., 1992, ApJ, 393, 289, 1992ApJ...393..289S
Shahbaz, T., Somers, M., Yudin, B. et al., 1997, MNRAS, 288, 4, 1027, 1997MNRAS.288.1027S
Vorontsov-Velyaminov, B., 1931, AN, 242, 201, 1931AN....242..201V
Webbink, R. F., Livio, M., Truran, J. W. et al., 1987, ApJ, 314, 653, 1987ApJ...314..653W
Yudin, B. F., Munari, U., 1993, A&A, 270, 165, 1993A&A...270..165Y
Zamanov, R., Boeva, S., Latev, G. Y. et al., 2023, A&A, 680, L18, 2023A&A...680L..18Z
Zhekov, S. A., Tomov, T., 2019, MNRAS, 489, 2, 2930, 2019MNRAS.489.2930Z