This is a fairly bright event but only lasts 0.2s. Must use 1x to get this. (I in fact had to go to 2x)
Alt=21, Az=212 in Ophiuchus
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I got a recording from TreeTop Ln off Graham Hill at the far east end of the empty lot, NE corner, about 25 ft from the eastern fence edge. At 2x. Seeing was poor, lots of scintillation. Sky was moonless, but looking over Santa Cruz with humidity the sky background brightness was brighter than I hoped.
Below are my reductions. PyOTE found a positive at the correct time, duration 0.2s. However, the NIE test failed completely. Different "start over" assumptions failed to improve on the noise histogram. However, for Kirk's miss on the other side of the path, it looks like the required shift which would then favor a positive for me. so I likely should have had an event. I will report it as a positive but with the proviso of "unsure", and let the auditors decide its fate.
magDrop report: percentDrop: 81.2 magDrop: 1.816 +/- 1.056 (0.95 ci)
DNR: 1.43
D time: [04:13:45.6655]
D: 0.6800 containment intervals: {+/- 0.0216} seconds
D: 0.9500 containment intervals: {+/- 0.0783} seconds
D: 0.9973 containment intervals: {+/- 0.1813} seconds
R time: [04:13:45.8655]
R: 0.6800 containment intervals: {+/- 0.0216} seconds
R: 0.9500 containment intervals: {+/- 0.0783} seconds
R: 0.9973 containment intervals: {+/- 0.1813} seconds
Duration (R - D): 0.2000 seconds
Duration: 0.6800 containment intervals: {+/- 0.0350} seconds
Duration: 0.9500 containment intervals: {+/- 0.0944} seconds
Duration: 0.9973 containment intervals: {+/- 0.1979} seconds
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PyOTE finds an event at the correct time, of correct duration. but, the NIE test gives it little significance |
Detectability of a 4 point occultation to 6 mag drop. |
The detected event at predicted event time, is 3 consecutive points at zero. No other place in the light curve has 3 points at zero, but still - the scintillation noise is high enough that - not knowing the full depth required of the real event -PyOTE gives a very poor noise test result. I'll report it as a positive and "unsure". |
I think that one should have the option in PyOTE to specify the magnitude of the drop so that the probabilities for a depth that low to be detected can be determined. My guess here is that the detection of the event would be improved if the search test excluded apparent drops that are too shallow to be valid. the NIE test above is surprisingly poor, as is.
Got a recording at 2x at Sunlit Lane.I don't see an event in my data for 2000 QR 135, 2x at the Berm. There isn't a distinct drop at predicted time over the noise. There are scattered drops throughout, but the whole curve meshes with the background level. Either a miss or undetectable. Max predicted duration was 0.17. PyOTE detectability test reports an event as short as 0.240s would likely be detectable.
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Got a recording at 2x from home. The star was "invisible". No data.
