Planck 2013 results X. Energetic particle effects: characterization, removal, and simulation. (arXiv:1303.5071v1 [astro-ph.CO]):
This paper presents the detection, interpretation and removal of the signal
resulting from interactions of high energy particles with the Planck High
Frequency Instrument (HFI). These interactions fall into two categories,
heating the 0.1 K bolometer plate and glitches in each detector time stream.
Glitch shapes are not simple single pole exponential decays and fall into a
three families. The glitch shape for each family has been characterized
empirically in flight data and removed from the detector time streams. The
spectrum of the count rate/unit energy is computed for each family and a
correspondence to where on the detector the particle hit is made. Most of the
detected glitches are from galactic protons incident on the Si die frame
supporting the micromachined bolometric detectors. At HFI, the particle flux is
~ 5 per square cm and per second and is dominated by protons incident on the
spacecraft with an energy >39 MeV, leading to a rate of typically one event per
second and per detector. Different categories of glitches have different
signature in timestreams. Two of the glitch types have a low amplitude
component that decays over nearly 1 second. This component produces an excess
noise if not properly removed from the time ordered data. We have used a glitch
detection and subtraction method based on the joint fit of population
templates. The application of this novel glitch removal method removes excess
noise from glitches. Using realistic simulations, we find this method does not
introduce signal bias.
RKS Note: Planck is in the same orbit as all proposed future X-ray missions, so this background will likely be the same.
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