70µm NARROW FOV PROFILE FITTING

Bill Wheaton

2005 October

The table below shows some results for a few AORs of 70µm NF data for several stars. Column 5 gives the nominal flux from the University of Arizona MIPS Flux Calbrators web page.

Fluxes were estimated by weighted least-squares fitting to a 4-parameter model including the source flux, a single background, and the source position in the frame, including all the good pixels on the good side of the array. The PRF was computed by integrating a 4000K STT PSF, generated centered in the good side of the array, over pixels using pixel boundaries based on the PIXSCAL sizes in the headers, with no correction for distortion. Flux estimates were computed using the calibration factor (2536 = 4*634) from the .FITS header.

The "Unweighted" columns give flux and standard error estimates obtained by simple averaging of the single-DCE estimates, with standard error obtained from 1./sqrt(N) of the Std.Dev of the DCE estimates, where N is the number of DCEs. The "Weighted" columns give the weighted average over DCEs for the fitted fluxes in each AOR, and the uncertainties have been adjusted by multiplying the standard weighted estimate of sigma by the sqrt of the reduced chisquare to the hypothesis that the DCE flux estimates are samples drawn from a population with a single unique flux for each AOR.

Because of the dearth of repeated observations of the same star available to date, nothing can yet be said about repeatability.

It is clear that saturation effects appear at higher flux levels.

AOR      PID  Campg HD star# F mJy  Date   Unweighted    Weighted      Run ID  
9189888  1708  5MC  HD100029  1110 031404 1018.1+/-27.6 1011.5+/-27.1 1025-1843
9190400  1708  5MC  HD131873  3140 031404 2725.1+/-68.4 2695.7+/-68.3 1025-1858
9653248  1710  7MC  HD082668  1520 050604 1464.5+/-31.2 1449.7+/-31.5 1025-1916
9942784  1712  9MC  HD163588   329 061804  261.7+/- 5.6  262.1+/- 5.7 1026-1727
12065024 1716 13MC  HD031398  1740 091904 1561.3+/-33.0 1546.7+/-33.2 1026-1846
13635072 1724 21MC  HD080493  1600 051205 1505.4+/-32.4 1492.0+/-31.1 1025-1829