2RE J0241-525: a nearby post-T Tauri visual binary system
Abstract
We present high-spatial-resolution X-ray observations, photometry and spectroscopy of the two low-mass, active stars proposed as optical counterparts to the extreme ultraviolet source 2RE J0241-525 (=EUVE J0241-530). It is confirmed that both stars, which are of types dK7e and dM3e and separated by 22 arcsec, are sources of soft X-ray emission and exhibit substantial chromospheric activity. Radial velocity measurements indicate that the two components are physically associated and most probably single. The projected equatorial velocities are measured as 75+/-3 and 11.7+/-0.7 km s^-1 for the hotter and cooler components respectively and, whilst the hotter component has a relatively high photospheric lithium abundance, log N(Li)=1.5+/-0.2, we are unable to detect any lithium in the cooler star. Isochrone fitting to this `mini-cluster' yields an age of 3-70 Myr and a distance of 19-60 pc. An empirical comparison of the lithium abundances with those for similar stars in young clusters and associations suggests a narrower age range of 5-30 Myr and a corresponding distance of 26-50 pc. We conclude that this object is a nearby post-T Tauri system, but we cannot locate any possible birth site. It appears unlikely that the system can have been ejected from a nearby open cluster in a two- or three-body encounter.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- August 1996
- DOI:
- 10.1093/mnras/281.3.1001
- Bibcode:
- 1996MNRAS.281.1001J
- Keywords:
-
- STARS: ACTIVITY;
- STARS: INDIVIDUAL: 2RE J0241-525;
- STARS: LATE-TYPE;
- STARS: PRE-MAIN-SEQUENCE;
- STARS: ROTATION;
- X-RAYS: STARS