Wilkinson Microwave Anisotropy Probe

Product Name
Bandpass Frequency Response


The frequency response of the two detectors in each of WMAP's twenty radiometers (two per differencing assembly) are provided in this dataset; there is one file per radiometer. Each file contains three columns:

  • The first column contains the frequency in GHz.
  • The second and third columns contain the frequency response for the two detectors comprising the radiometer; these values are in linear Rayleigh-Jeans units that have since been normalized to a maximum of one, so these columns are dimensionless.

In principal the bandpass data for the two detectors should be weighted by their response to a thermal spectrum corresponding to how the WMAP data is calibrated in flight. In practice, weighting this bandpass data based upon the area beneath each response curve should be sufficient. It is worth noting that the center frequencies have drifted over time (Bennett et al. 2013); the effective frequency calculator on the software page and the corresponding IDL procedures in the delivered IDL library apply a correction factor to account for this drift over the nine-year mission.

These are the same files released in the fourth WMAP data release.

For more information, please see:

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Goddard Space Flight Center, National Aeronautics and Space Administration
HEASARC Director: Dr. Alan P. Smale
LAMBDA Director: Dr. Eric R. Switzer
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