1. Searching for Radio Stars
T. Christian
Macaulay Honors College at the City College of New York
Amy Kimball

2. What kinds of stars would be Radio Stars?
1. Morgan Keenan Spectral Classification
What kinds are stars are likely to be Radio Stars?

3. Low mass stars are ACTIVE
Convection moves material causing a magnetic field
2. Introduction to Stars,Galaxies and the Universe – Prof. Richard Pogge
3. Sychrotron Radiation

4. Looking for Radio Stars
Low mass stars are faint * They need to be nearby to be seen Nearby stars have more apparent motion in the sky
2004
1997
4. Proper Motion of Barnard’s Star

5. Possible Contaminating Sources
Quasars & Galaxies

6. Considering Proper Motion
FIRST
GAIA
WISE
Pan - STARRS(PS1)
First = Radio –
Gaia = Optical
Wise = Infrared
Pan-STARRS = Optical – 2010s

7. GOLD STAR okay Candidate Types
Gaia Wise Match ID ≠ First Wise Match ID
AND
First Wise Match is empty
GOLD STAR
okay
Gaia Wise Match ID == First Wise Match ID

8. Selection/Elimination Process
Optical Colors from Pan-STARRS
Infrared Colors from WISE

9. To be considered on the stellar locus, a source had to either:
Have the stellar locus contained within twice its error bounds in either the x or y direction OR
Was within .05 of the stellar locus
Cyan – non Stellar
Blue - Stellar

10. Wise Color Color Diagrams
Every source that was below 1.5 on the Color -Color chart was considered a star

11. 🌟Our Gold Star Candidates 🌟

12. Gold Star Candidate 1
GALAXY

13. Gold Star Candidate 2
QUASAR

14. Possible Radio Stars

15. Possible Radio Stars

16. Results
Stars Compact in Radio – 5 Star Extended in Radio – 1 No ID and No Spectra and Compact – 86 QSOs Radio Source no Spectra – 27 Galaxies – 94 TOTAL CANDIDATES = 380
Only 1.3% of the candidates are stars
Stars Found

18. Total Coordinates 946432 Stars 5 Unknown Objects 91
Real vs Random
Total Coordinates Stars 5 Unknown Objects 91
Total Coordinates * 7.3 = ~ Stars 0 * 7.3 = 0 Unknown Objects 4 * 7.3 = 29.2

19. Conclusions
Lots of Quasars and Galaxies These objects are radio bright and dominate in the Radio Survey They can mimic the optical colors of stars through their redshift Low Mass-Stars are faint in Radio Radio (<1 mJy) We are searching for the lower limits of detection of the instrumentation i.e they would be too dim to detect

20. Next Steps
Creating a candidate list for follow-up spectra confirmation