Be. Mcarthur et al., Astrometry with Hubble Space Telescope Fine Guidance Sensor 3: The parallax of the cataclysmic variable RW Triangulum, ASTROPHYS J, 520(1), 1999, pp. L59-L62
RW Triangulum (RW Tri) is a 13th magnitude nova-like cataclysmic variable s
tar with an orbital period of 0.2319 days (5.56 hr). Infrared observations
of RW Tri indicate that its secondary is most likely a late-K dwarf (Dhillo
n). Past analyses predicted a distance of 270 pc, derived from a blackbody
fit to the spectrum of the central part of the disk (Rutten, van Paradijs,
gr Tinbergen), Recently completed Hubble Space Telescope Fine Guidance Sens
or interferometric observations allow us to determine the first trigonometr
ic parallax to RW Tri. This determination puts the distance of RW Tri at 34
1(+38)(-31), one of the most distant objects with a direct parallax measure
ment. We compare our result with methods previously employed to estimate di
stances to cataclysmic variables.