Summary Details for KELT Praesepe Exoplanet Archive-ETSS Data Sets
Telescope
The 4.5cm KELT-North Telescope (Winer Observatory, Arizona).
Instruments
The KELT detector is an Apogee Instruments AP16E thermoelectrically cooled camera, using a front-side illuminated 4096 x 4096 Kodak KAF-16801E CCD with 9-micron pixels.
Observed Region
For the Praesepe data set, KELT used a 10.8° x 10.8° field of view, with a pixel scale of 9.5 arcseconds. The field was centered on the Praesepe open cluster at J2000 08h 40m 06s, +19d 41m 06s.
Observed Filters
KELT utilized a Kodak Wratten No. 8 filter. The filter essentially transmits all light redward of 500nm. In practice the filter acts as a very broad Johnson R-band filter, which we call RK.
Photometric Technique
Because all data in the set was taken with the above filter, we calibrated the absolute magnitudes of the observations to RK, listed as Johnson R, even though there is a significant color term which could be as large as -0.3 magnitudes for very blue stars, to +0.8 magnitudes for very red stars. Details of the photometric calibrations are given in the paper discussing the KELT Praesepe observations, with a more comprehensive discussion of the filter and calibrations in the KELT instrumentation paper.
Exposure times were 60s.
Data Ranges
The data parameters fall into the following approximate ranges:
| Field | Min | Max |
|---|---|---|
| RA (2000) | 08 17 45.52 | 09 03 20.67 |
| Dec (2000) | 13 35 36.9 | 24 09 37.6 |
| HJD of the observation |
2453415.775 | 2453488.703 |
| RK magnitude | 5.792 | 17.566 |
| Total number of stars | - | 66637 |
| Number of epochs | - | ~3000 |
Figures and Images
Figure 1: Greyscale image of the Praesepe cluster.
Figure 2:
(a) RMS vs. RK magnitude for the 66,638 KELT stars, calculated from 105 observations over the course of one night.
(b) RMS plot for the same stars using all 3,137 observations over the full 34 nights. Structure in the plots results from the separate reductions of the four sections of the field to deal with the changes in the FWHM pattern.
Download Data Sets
| KELT Praesepe Interactive Table | Interactive table Data Column Definitions |
| KELT Praesepe summary file | IPAC ASCII format table |
| KELT Praesepe light curves | Download scripts |
Primary References
- "The Kilodegree Extremely Little Telescope (KELT): A Small Robotic Telescope for Large-Area Synoptic Surveys", Pepper et al. 2007, PASP, 119, 923
- "A Photometric Survey for Variables and Transits in the Field of Praesepe with the Kilodegree Extremely Little Telescope", Pepper et al. 2008, AJ, 135, 907
