1. The KELT Follow-Up Network: Crowd-Sourced Photometry
Rob Siverd (LCOGT)
Hotwired IV

2. What is KELT? Kilodegree Extremely Little Telescope
Wide-field photometric survey for bright transiting exoplanets (~15 discovered!)
Coarse pixel scale (23 arcsec, defocused)
Wide bandpass
Amateur- and commercial-grade hardware
Stable (but ugly) PSF
Difference Imaging Pipeline (ISIS-based)
Bright, high-value targets (8 < V < 10)

3. Why 8 < V < 10?

4. KELT-North and KELT-South
Pepper, J., 2012, “The KELT-South Telescope”, PASP, 124, 230
Pipeline and reductions:
Siverd, R. J., et al. 2012, “KELT-1b: A Strongly Irradiated, Highly Inflated, Short Period, 27 Jupiter-mass Companion Transiting a Mid-F Star”, ApJ, 761, 123
Pepper, J., et al. 2007, "The Kilodegree Extremely Little Telescope (KELT): A Small Robotic Telescope for Large-Area Synoptic Surveys", PASP, 119, 923

5. Bandpass

6. Bandpass

7. Performance
~50,000 stars per field
1% error for V < 10

8. Observing Fields
Colors indicate differing time baseline

9. KELT’s FOV
26°x26°

10. KELT’s FOV 4.6’ x 4.6’ 26°x26° KELT-North Keck = 10.4 meters
FTN = 2 meters
4.6’ x 4.6’
26°x26°

11. KELT’s FOV 4.6’ x 4.6’ 4.6’ x 4.6’ 26°x26° KELT-North
Faulkes Telescope North
Keck = 10.4 meters
FTN = 2 meters
4.6’ x 4.6’
4.6’ x 4.6’
26°x26°

12. KELT’s FOV
KELT-North
Faulkes Telescope North
Keck = 10.4 meters (Obtained with NIRC2 adaptive optics) FOV ~ 1/5 KELT pixel
FTN = 2 meters (Part of LCOGT)
4.6’ x 4.6’
4.6’ x 4.6’
26°x26°

13. Extra Photometry Required
Depth uncertainty due to blending/dilution (consequence of our DIA pipeline)
Source confusion (giant pixels)
False positives due to imperfect calibration and pointing issues (e.g., hot pixels)

14. Solution: Photometry Crowd
~50 telescopes around the world
Sites include backyards and pro observatories
Apertures from 0.3m (12”) to 2m
Wide variety of filters available
Amateurs, professionals, and educators
Observations taken at leasure (or request)
Results ed to Google Group
Key software contributions from collaborators

15. Solution: Photometry Crowd

16. Typical Results

17. Candidate Management (Google Docs)

18. Candidate Dissemination: Tapir
Public version (exoplanets.org):
Public code:

19. Tapir Search Interface

21. Example Output: BOS

24. Motivation and Incentives
Fun!
Scientific interest
Authorship or coauthorship
Learning new skills
Challenging
Bored of “pretty pictures” …