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BSM transformation coefficients

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HQA
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Joined: 2010-05-10

The Bright Star Monitor is actually one of the best determined systems in AAVSOnet.  We image standard fields every night, and with the large field of view, we cover many standards in each image.  On a typical night, we cover about 300 Landolt standards that form the basis of the transformation coefficient calculation.  BSM uses Schuler glass filters, using the Bessell formulation, along with a refractor and an ST-8XME camera.  This combination actually matches the Landolt/Johnson/Cousins system pretty closely.  The results from BSM will be used in the upcoming CCD Photometry book.


For 10 nights from 101114-101202, here are the coefficients and mean extinction values:

Tv = -0.010 +/- 0.006

Tbv = 0.990 +/- 0.015

Tvr = 1.001 +/- 0.008

Tri = 0.968 +/- 0.017

Tvi = 0.994 +/- 0.010

 

kv = 0.137 +/- 0.013

kbv = 0.126 +/- 0.022

kvr = 0.038 +/- 0.010

kri = 0.047 +/- 0.010

kvi = 0.084 +/- 0.014

Arne

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