An Independent Determination of WFC 3-IR Zeropoints and Count Rate Non-Linearity from 2 MASS Asterisms

@inproceedings{Riess2011AnID,
  title={An Independent Determination of WFC 3-IR Zeropoints and Count Rate Non-Linearity from 2 MASS Asterisms},
  author={Adam G. Riess},
  year={2011}
}
We report the results from the CAL/WFC3 program 12335 to constrain the effect of count-rate non-linearity on the WFC3-IR detector by comparing the fluxes of 24 bright stars in asterisms observed with WFC3-IR and 2MASS. An incidental finding is an underestimate of the sample time of the first read for WFC3-IR (i.e., the zeroeth read) which is used to determine photometry for bright sources reaching saturation before the second read. After accounting for differences in zeropoint definitions and… CONTINUE READING