The negative points in MJD 56007-56008 (Mar 21 - 22, 2012) are due to the contamination by the sun.
A leak of the solar X-ray passed near the source. You can see it in the daily images.
The data is updated in every day.
The data was processed with version 7L, where both 1650V and 1550V data
Evaluation of the shadow of solar paddles are improved. This decreased the
number of dropping data points.
A-system camera 0 (gas leaking camera) is also used until 57900 MJD.
There, the flux has a large uncertainty (a few tens of % in 2-4 keV).
Even in 4-10 keV, the data have larger uncertainty than those in
the other normal cameras.
After 57900 MJD, A-system Camera 0 is no-longer used in version 7L,
and the data have smaller error bars, although data gaps appears
for some sources.
Light curve Data
README for light curve data