THE SOLAR NEIGHBORHOOD. XXXIII. PARALLAX RESULTS FROM THE CTIOPI 0.9 m PROGRAM: TRIGONOMETRIC PARALLAXES OF NEARBY LOW-MASS ACTIVE AND YOUNG SYSTEMS

Abstract

We present basic observational data and association membership analysis for 45 young and active low-mass stellar systems from the ongoing RECONS photometry and astrometry program at the Cerro Tololo Inter-American Observatory. Most of these systems have saturated X-ray emission (log LX L bol > −3.5) based on X-ray fluxes from the ROSAT All-Sky Survey, and many are significantly more luminous than main-sequence stars of comparable color. We present parallaxes and proper motions, Johnson-Kron-Cousins V RI photometry, and multiplicity observations from the CTIOPI program on the CTIO 0.9m telescope. To this we add low-resolution optical spectroscopy and line measurements from the CTIO 1.5m telescope, and interferometric binary measurements from the Hubble Space Telescope Fine Guidance Sensors. We also incorporate data from published sources: JHK S photometry from the 2MASS point source catalog; X-ray data from the ROSAT All-Sky Survey; and radial velocities from literature sources. Within the sample of 45 systems, we identify 21 candidate low-mass pre-main-sequence members of nearby associations, including members of β Pictoris, TW Hydrae, Argus, AB Doradus, two ambiguous ≈30 Myr old systems, and one object that may be a member of the Ursa Major moving group. Of the 21 candidate young systems, 14 are newly identified as a result of this work, and six of those are within 25 parsecs of the Sun.

CARMENES input catalogue of M dwarfs

“…We started to fill the CARMENES database with the M dwarfs from the Research Consortium on Nearby Stars 2 , which catalogues all known stars with measured astrometric parallaxes that place them within 10 pc (e.g., Henry et al 1994;Kirkpatrick et al 1995;Riedel et al 2014;Winters et al 2015). The RECONS stellar compilation was next completed with the Palomar/Michigan State University survey catalogue of nearby stars (PMSU -Reid et al 1995Hawley et al 1996;Gizis et al 2002).…”

“…(a) Some other publications and meta-archives that we have searched for potential CARMENES targets are Kirkpatrick et al (1991), Gizis (1997), Gizis & Reid (1997), Gizis et al (2000b), Henry et al (2002Henry et al ( , 2006, Mochnacki et al (2002), Gray et al (2003), Bochanski et al (2005), Crifo et al (2005), Lodieu et al (2005), Scholz et al (2005), Phan-Bao & Bessell (2006), Reylé et al (2006), Riaz et al (2006), Caballero (2007Caballero ( , 2009Caballero ( , 2012, Gatewood & Coban (2009), Shkolnik et al (2009, 2012, Bergfors et al (2010), Johnson et al (2010), Boyd et al (2011), Irwin et al (2011), West et al (2011, Avenhaus et al (2012), Deacon et al (2012), Janson et al (2012, 2014), Frith et al (2013, Jódar et al (2013), Malo et al (2013), Aberasturi et al (2014), Dieterich et al (2014), Riedel et al (2014), Yi et al (2014), , and the DwarfArchive at http://dwarfarchive.org. (b) PMSU: Reid et al (1995Reid et al ( , 2002; Hawley et al (1996); Gizis et al (2002).…”

“…(c) With spectral types derived from spectroscopy in this work. (d) RECONS: Henry et al (1994Henry et al ( , 2006; Kirkpatrick et al (1995); Jao et al (2011);Riedel et al (2014); Winters et al (2015) and references therein.…”

A dusty M5 binary in theβPictoris moving group

“…Although neither the MagE or UVES spectra could be telluric corrected, the Na I index, a measure of surface gravity (Lawson et al 2009), has values in the range 1.16-1.18 and agrees well with those of other β Pic members (see, e.g., Fig. 5 in Riedel et al 2014). The numerous emission lines, strong Li absorption, and weak Na I index all suggest a young age for this system.…”

“…Both components of LDS 5606 exhibit very red colors comparable to those of stars known to host warm circumstellar dust disks. Riedel et al 2014) and the LDS 5606 system along with theoretical 10 and 20 Myr isochrones (Baraffe et al 1998;Siess et al 2000). The two models differ substantially at these late spectral types, which makes identification of additional late-type members of moving groups invaluable to better constrain stellar evolution models.…”