ROTATIONAL VELOCITIES FOR M DWARFS

By James S. Jenkins, L. Ramsey, H. Jones, Y. Pavlenko, José A. Gallardo, J. Barnes, D. Pinfield. 2009

137 citations recorded by the source corpus.

We present spectroscopic rotation velocities (v sin i) for 56 M dwarf stars using high-resolution Hobby–Eberly Telescope High Resolution Spectrograph red spectroscopy. In addition, we have also determined photometric effective temperatures, masses, and metallicities ([Fe/H]) for some stars observed here and in the literature where we could acquire accurate parallax measurements and relevant photometry. We have increased the number of known v sin i values for mid M stars by around 80% and can confirm a weakly increasing rotation velocity with decreasing effective temperature. Our sample of v sin is peak at low velocities (∼3 km s−1). We find a change in the rotational velocity distribution between early M and late M stars, which is likely due to the changing field topology between partially and fully convective stars. There is also a possible further change in the rotational distribution toward the late M dwarfs where dust begins to play a role in the stellar atmospheres. We also link v sin i to age and show how it can be used to provide mid-M star age limits. When all literature velocities for M dwarfs are added to our sample, there are 198 with v sin i ⩽ 10 km s−1 and 124 in the mid-to-late M star regime (M3.0–M9.5) where measuring precision optical radial velocities is difficult. In addition, we also search the spectra for any significant Hα emission or absorption. Forty three percent were found to exhibit such emission and could represent young, active objects with high levels of radial-velocity noise. We acquired two epochs of spectra for the star GJ1253 spread by almost one month and the Hα profile changed from showing no clear signs of emission, to exhibiting a clear emission peak. Four stars in our sample appear to be low-mass binaries (GJ1080, GJ3129, Gl802, and LHS3080), with both GJ3129 and Gl802 exhibiting double Hα emission features. The tables presented here will aid any future M star planet search target selection to extract stars with low v sin i.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/932a55549766b6ef2c433fd4fd959c90dc2362a6

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. B. Goldman
2. N. Joshi
3. A. Reiners
4. W. Jao
5. B. Mcarthur
6. G. Benedict
7. E. Nelan
8. Phillip Cargile

In Instrumentation

1. W. Jao
2. N. Joshi
3. B. Mcarthur
4. A. Reiners
5. G. Benedict
6. B. Goldman
7. E. Nelan
8. Phillip Cargile

Citations in the corpus

• A CATALOG OF ROTATION AND ACTIVITY IN EARLY-M STARS (2012, methodology): “During the course of our project, Jenkins et al. (2009) and Browning et al. (2010) added more stars to this list, and a few other rotational velocities were presented in Reiners (2007) and Reiners & Basri (2007).”
• THE SOLAR NEIGHBORHOOD. XXXVII. THE MASS–LUMINOSITY RELATION FOR MAIN-SEQUENCE M DWARFS (2016, background): “Relative metallicites could be inferred from single project efforts (Bean 2007; Jenkins et al. 2009) despite their lack of agreement, and such comparisons clearly indicated that some stars possess fewer metals than others.”
• FUNDAMENTAL PARAMETERS AND SPECTRAL ENERGY DISTRIBUTIONS OF YOUNG AND FIELD AGE OBJECTS WITH MASSES SPANNING THE STELLAR TO PLANETARY REGIME (2015, unknown): “…(1991), (66) Lucas et al. (2010), (67) Looper et al. (2007), (68) Reid et al. (2003a), (69) Artigau et al. (2010), (70) Giclas et al. (1961), (71) Jenkins et al. (2009), (72) Costa et al. (2006), (73) Reid (1987), (74) Kirkpatrick et al. (1991), (75) Wilson et al. (2001), (76) Burgasser et al.…”