Research

Rotation & Activity in Open Clusters

My dissertation focuses on the connection between rotation and activity in Praesepe & The Hyades. I compare rotation distributions and various activity-rotation relations to model predictions for how stars spin down as they age.

Most recently, I measured rotation periods for low-mass Hyades members using K2 data, including the first rotation periods for fully convective Hyads. I found that recent models mostly replicate the observed rotation period distrubtion for G-K dwarfs and for fully convective stars. Early M dwarfs, on the other hand, do not match the models, likely due to a change in the magnetic field structure and/or dynamo around 0.5-0.6 Solar Masses. These results were published in Douglas et al. (2016)

For my first-year project at Columbia, I used optical spectra and photometric periods from our own observations and a variety of literature sources to compile one of the most extensive samples of chromospheric activity and rotation for a single-age population. I found that coronal and chromospheric activity indices depend differently on rotation. The results were published in Douglas et al. (2014).


 

Physical Parameters of Brown Dwarfs

I am working on an MCMC code that fits synthetic spectra to observed spectra of brown dwarfs. I'm carrying out this work as part of BDNYC, a brown dwarf research group based at the American Museum of Natural History and led by Kelle Cruz and Emily Rice. My goals are to determine believable uncertainties on the best-fit parameters that result from model fits, and to determine how well these parameters can be constrained using only low- or moderate-resolution data. A paper on this work is in prep.

Contact

Email: StephanieTDouglas [At] gmail [DoT] com

Twitter: @stephtdouglas

Tumblr: @spotsandloops

Github: stephtdouglas

FigShare: stephtdouglas