Basic data (System:663)

C1900.0 :11083-2555
C2000.0 :111312497-26275425
Comp. :
Magn. : 7.25 ; 9.02
Spect. :A3e ; (G5)


CD -25 8531CPD -25 4711GAIADR2 3532612598122182272GCVS TT Hya
HD 97528HIP 54807


ElementValueStd. dev.
Period (d.):6.9534
Periastron time (xJD-2,400,000.0):24620.488
Reference T0/epoch:JD
omega primary (deg.):319.8
K1 (km/s):41.2
K2 (km/s):
V0 (km/s):+17.5
sigma residuals primary:
sigma residuals secondary:
#RV primary:
#RV secondary:
Derived quantities (on the fly, from the above quantities)
a1sini (km):3.91092e+060
f(m) (sol.mass):0.04948820


The elements derived by Sahade and Cesco have been preferred although the
solution was a graphical one and Lucy & Sweeney question the reality of the
orbital eccentricity. R.F. Sanford (Astrophys. J., 86, 153, 1937) found a
smaller value of K1. D.M. Popper, as quoted by A.G. Kulkarni and K.D. Abhyankar
(J. Astrophys. Astron., 2, 119, 1981), has found preliminary values of K1=35
km/s and K2=130 km/s. Undoubtedly, Popper's study -- when it is published --
will supersede the others. The first observations of the D-line of the
secondary spectrum were reported by E.W. Miller and D.H. McNamara, (Publ.
Astron. Soc. Pacific, 75, 346, 1963) who also noted the presence of H-alpha in
emission. Several emission-lines of non-stellar origin, in the ultraviolet,
have been reported by M.J. Plavec (Bull. Am. Astron. Soc., 19, 708, 1987).
These will probably turn out to be related to distortions in the velocity-curve
found by Sahade and Cesco. Photoelectric UBV light-curves have been obtained
and analyzed by Kulkarni and Abhyankar (op. cit.) and re-analyzed by J. Koul
and K.D. Abhyankar (J. Astrophys. Astron., 3, 93, 1982) and P.B. Etzel (Bull.
Am. Astron. Soc., 18, 976, 1986). Agreement between the various analyses is not
fully satisfactory. The orbital inclination is well over 80 deg, the magnitude
difference (Delta V) between components is between 1.0m and 1.5m. Spectral
types are A0 V or A1 V and K1 III or G8 III.


Encapsulated PostScript file


Valid HTML 4.01 Transitional