This page describes the format for the HAT light curves generated by the LCC server. We include metadata about the object, the telescopes observing it, and environmental conditions at the time of observation. In general, HAT uses aperture photometry using three apertures to maximize photometric precision throughout the effective 5-sigma magnitude range of the instruments.

Reading and working with these light curves is described in the csvlc docs page.

Object metadata key listing

Metadata key Description
objectid object ID
hatid HAT ID
twomassid 2MASS ID
ra RA [deg]
decl Dec [deg]
jmag 2MASS J
hmag 2MASS H
kmag 2MASS Ks
ndet total number of observations
stations observed by telescopes
network observation network
lcapertures aperture definitions [aperture number, size in pixels]
filters telescope filter definitions [code, short name, description]
lastupdated last updated at UNIX time
lcserver HATLC generator gitref
lcinstnormcols light curve normalization description

Light curve column listing

Column Key Numpy dtype Description
0 rjd f8 time of observation in Reduced Julian date (JD = 2400000.0 + RJD)
1 bjd f8 time of observation in Baryocentric Julian date (BJD_TDB)
2 net i8 network of telescopes observing this target
3 stf i8 station ID of the telescope observing this target
4 cfn i8 camera frame serial number
5 cfs U20 camera subframe id
6 ccd i8 camera CCD position number
7 prj U20 project ID of this observation
8 fld U20 observed field name
9 frt U20 image frame type [flat, object, etc.]
10 flt i8 filter ID from the filters table
11 exp f8 exposure time for this observation in seconds
12 tfs i8 telescope focus setting
13 ttt f8 telescope tube temperature [deg]
14 tms U20 telescope mount state (tracking, drizzling, etc.)
15 mph f8 moon phase at this observation
16 iha f8 hour angle of object at this observation
17 izd f8 zenith distance of object at this observation
18 xcc f8 x coordinate on CCD chip
19 ycc f8 y coordinate on CCD chip
20 bgv f8 sky background measurement around object in ADU
21 bge f8 error in sky background measurement in ADU
22 fsv f8 source extraction S parameter (1/[the PSF spatial RMS]^2)
23 fdv f8 source extraction D parameter (the PSF ellipticity in xy)
24 fkv f8 source extraction K parameter (the PSF diagonal ellipticity)
25 aim_000 f8 aperture photometry raw instrumental magnitude in aperture 000
26 aim_001 f8 aperture photometry raw instrumental magnitude in aperture 001
27 aim_002 f8 aperture photometry raw instrumental magnitude in aperture 002
28 aie_000 f8 aperture photometry raw instrumental mag error in aperture 000
29 aie_001 f8 aperture photometry raw instrumental mag error in aperture 001
30 aie_002 f8 aperture photometry raw instrumental mag error in aperture 002
31 aiq_000 f8 aperture photometry raw instrumental mag quality flag, aperture 000
32 aiq_001 f8 aperture photometry raw instrumental mag quality flag, aperture 001
33 aiq_002 f8 aperture photometry raw instrumental mag quality flag, aperture 002
34 arm_000 f8 aperture photometry fit magnitude in aperture 000
35 arm_001 f8 aperture photometry fit magnitude in aperture 001
36 arm_002 f8 aperture photometry fit magnitude in aperture 002
37 aep_000 f8 aperture photometry EPD magnitude in aperture 000
38 aep_001 f8 aperture photometry EPD magnitude in aperture 001
39 aep_002 f8 aperture photometry EPD magnitude in aperture 002
40 atf_000 f8 aperture photometry TFA magnitude in aperture 000
41 atf_001 f8 aperture photometry TFA magnitude in aperture 001
42 atf_002 f8 aperture photometry TFA magnitude in aperture 002