Measuring stellar rotation periods with Kepler K2 light curves
Research Mentor(s)
Covey, Kevin R.
Description
Our aim is to measure stellar rotation periods from the Kepler K2 Campaign 2 light curves to study the evolution of stars’ angular momentum content. Our primary targets are members of the ~10 Million year-old cluster, Upper Scorpius: by comparing the rotation periods we measure for young stars in Upper Sco to those measured for stars in older clusters, we can better understand how stars spin up as they approach their main sequence radii, and help develop an age diagnostic for stars that are not in clusters. We measured rotation periods for by calculating an autocorrelation function for the Kepler K2 light curve of each of our targets. The autocorrelation function identifies the presence of periodic structures in a light curve by measuring the degree of similarity between the light curve and a copy that has been shifted by some time t. To measure the period for each target, we search the autocorrelation function for the shift t that maximizes the similarity of the light curve and its time-shifted copy. We summarize the current state of our period measurement algorithm and describe plans for further development.
Document Type
Event
Start Date
14-5-2015 10:00 AM
End Date
14-5-2015 2:00 PM
Department
Physics/Astronomy
Genre/Form
student projects; posters
Subjects – Topical (LCSH)
Stars--Rotation; Stellar oscillations
Type
Image
Rights
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this documentation for commercial purposes, or for financial gain, shall not be allowed without the author's written permission.
Language
English
Format
application/pdf
Measuring stellar rotation periods with Kepler K2 light curves
Our aim is to measure stellar rotation periods from the Kepler K2 Campaign 2 light curves to study the evolution of stars’ angular momentum content. Our primary targets are members of the ~10 Million year-old cluster, Upper Scorpius: by comparing the rotation periods we measure for young stars in Upper Sco to those measured for stars in older clusters, we can better understand how stars spin up as they approach their main sequence radii, and help develop an age diagnostic for stars that are not in clusters. We measured rotation periods for by calculating an autocorrelation function for the Kepler K2 light curve of each of our targets. The autocorrelation function identifies the presence of periodic structures in a light curve by measuring the degree of similarity between the light curve and a copy that has been shifted by some time t. To measure the period for each target, we search the autocorrelation function for the shift t that maximizes the similarity of the light curve and its time-shifted copy. We summarize the current state of our period measurement algorithm and describe plans for further development.