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taos 2 years result: on astroph

2 years of TAOS data lead to the strongest upper limit in the ~km region of the power spectrum. the limit is shown here as a limit to the power of a power law anchored to the smallest KBO observed directly (Bernstein et al. 2001). under a power law assumption any line steaper then the solid line in the plot is rule out to 95% confidence.

TAOS: a survey to see beyond the observable		TAOS is a blind occultation survey for the Kuiper Belt: we observe luminous stars awaiting serendipitous alignment of Kuiper Belt Objects. This is the only way to derive information about the small size objects in the Kuiper Belt: anything smaller then ~10km is not directly observable. The transit of a dark object of the size of Trans Neptunian Objects at the distance of the Kuiper Belt is dominated by diffraction effects: it projects on earth a diffraction pattern
	the variation in the flux might be observable. diffraction patterns are larger then the object that generates them for sum-km objects. as the KBO crosses the line of sight the duration of a diffraction event is generally no shorter then 0.1 second. the flux decrease however can be arbitrarily shallow, proportionally to the size of the occulter (smaller objects cause shallower flux troughs)	effect of time integration:

we observe at 5hz for now: zippermode photometry by shifting the charges by only a fraction of the rows on the CCD to read:

a block of rows (a rowblock, typically 76 rows) shows all the star-images that were in the original image in a compressed form

see how parameters such as size, distance of the KBO, magnitude of the star, impact parameter affect what we see (simulation tool prepared by Taryn Nihei, Matthew Lehner, Joe Giammarco, S.K. King and myself) diameter, distance, impact parameter Nihei et al. 07 Lehner et al. 08

a long one

a shorter, more generic one

a poster

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