Observation and analysis of X181590 on Nov. 14, 2010 (UTC)

Nov. 27, 2010
Kazuhisa Miyashita

The catalogue's detail of R3230 is as follows.
Catalogue details

Catalogue details

 XZ 181590
 RA =  22  3 49.6241   PM = -0.00145s
Dec = - 7 49 59.709    PM = -0.0327"
 Mv = 11.08, Mb = 12.72, Mr = 10.22    Spectrum __    Dia: .0003" [Estimated]

Star is the primary of the following pair
Name    Cmpt   Yr1  Yr2: PA1   PA2  :   Sep1   Sep2  :  Mag1  Mag2:     #1      #2  mean
RST4704       1939 1991: 146.0 147.0:   1.900   1.800: 11.34 11.46: X181590  ------

WDS Discoverer codes
RST  Rossiter, R.A.                      

Light curve and explanation

This is a faint star occultation, and the light curve scattered with air scintillation and CCD's noise. The FFT low pass filtre was applied to reduce these noise. As a result, a rather clear step is obtained.

Comments from Brian Loader IOTA double star coordinator:
It does look that there is a step there, rather hidden in the noise.
The expected step time was 6.52 seconds, so in reasonable agreement with your observation. Again it would be good to get further observations to confirm this. There appears to be one or two possible opportunities in 2011, but the magnitude is likely to make observing difficult with any telescope less than 30cm, or at brighter phases of the moon.

Miyashita's observation
Raw light curve.

FFT low pass filtre applied.

Calculation of component's magnitude.