Dear Guest
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The lightcurves presented here are part of a paper entitled 'Long-term optical variability properties of the Palomar-Green quasars' by Uriel Giveon, Dan Maoz, Shai Kaspi, Hagai Netzer, and Paul S. Smith, accepted on February 16, 1999 by the MNRAS (see also http://xxx.lanl.gov/abs/astro-ph/9902254).

In the following directories, named after the objects, you will find a directory for each band used (B and R), and in it a file named 'lightcurve' containing the following data:
Column 1 - Julian date
Column 2 - Apparent magnitude
Column 3 - Total photometric error
Column 4 - Error due to the scatter in the reference star magnitudes
Column 5 - PSF fitting error of the quasar
Column 6 - Number of comparison stars used in that epoch
Column 7 - Image name (consists of observation date and serial number)

The last row gives the statistics of the lightcurve:
Number of data points
Total period
Mean sampling interval
Mean magnitude
Median magnitude
Standard deviation of the lightcurve
Mean difference of magnitudes
Median difference of magnitudes
Maximal difference of magnitudes
Mean gradient of the lightcurve (in mag per year)
Median gradient of lightcurve (in mag per year)
Maximal gradient of lightcurve (in mag per year)

allightcurves.tar.gz is a tar file containing these lightcurves together for convenience.

Individual files:
pg0026/B/lightcurve
pg0026/R/lightcurve
pg0052/B/lightcurve
pg0052/R/lightcurve
pg0804/B/lightcurve
pg0804/R/lightcurve
pg0838/B/lightcurve
pg0838/R/lightcurve
pg0844/B/lightcurve
pg0844/R/lightcurve
pg0923/B/lightcurve
pg0923/R/lightcurve
pg0953/B/lightcurve
pg0953/R/lightcurve
pg1001/B/lightcurve
pg1001/R/lightcurve
pg1012/B/lightcurve
pg1012/R/lightcurve
pg1048/B/lightcurve
pg1048/R/lightcurve
pg1100/B/lightcurve
pg1100/R/lightcurve
pg1114/B/lightcurve
pg1114/R/lightcurve
pg1115/B/lightcurve
pg1115/R/lightcurve
pg1121/B/lightcurve
pg1121/R/lightcurve
pg1151/B/lightcurve
pg1151/R/lightcurve
pg1202/B/lightcurve
pg1202/R/lightcurve
pg1211/B/lightcurve
pg1211/R/lightcurve
pg1226/B/lightcurve
pg1226/R/lightcurve
pg1229/B/lightcurve
pg1229/R/lightcurve
pg1307/B/lightcurve
pg1307/R/lightcurve
pg1309/B/lightcurve
pg1309/R/lightcurve
pg1322/B/lightcurve
pg1322/R/lightcurve
pg1351/B/lightcurve
pg1351/R/lightcurve
pg1354/B/lightcurve
pg1354/R/lightcurve
pg1402/B/lightcurve
pg1402/R/lightcurve
pg1404/B/lightcurve
pg1404/R/lightcurve
pg1411/B/lightcurve
pg1411/R/lightcurve
pg1415/B/lightcurve
pg1415/R/lightcurve
pg1426/B/lightcurve
pg1426/R/lightcurve
pg1427/B/lightcurve
pg1427/R/lightcurve
pg1444/B/lightcurve
pg1444/R/lightcurve
pg1512/B/lightcurve
pg1512/R/lightcurve
pg1519/B/lightcurve
pg1519/R/lightcurve
pg1545/B/lightcurve
pg1545/R/lightcurve
pg1613/B/lightcurve
pg1613/R/lightcurve
pg1617/B/lightcurve
pg1617/R/lightcurve
pg1626/B/lightcurve
pg1626/R/lightcurve
pg1700/B/lightcurve
pg1700/R/lightcurve
pg1704/B/lightcurve
pg1704/R/lightcurve
pg2130/B/lightcurve
pg2130/R/lightcurve
pg2233/B/lightcurve
pg2233/R/lightcurve
pg2251/B/lightcurve
pg2251/R/lightcurve