Planck2013 results. X. HFI energetic particle effects: characterization, removal, and simulation

Abstract

We describe the detection, interpretation, and removal of the signal resulting from interactions of high energy particles with the Planck High Frequency Instrument (HFI). There are two types of interactions: heating of the 0.1 K bolometer plate; and glitches in each detector time stream. The transient responses to detector glitch shapes are not simple single-pole exponential decays and fall into three families. The glitch shape for each family has been characterized empirically in flight data and these shapes have been used to remove glitches from the detector time streams. The spectrum of the count rate per unit energy is computed for each family and a correspondence is made to the location on the detector of the particle hit. Most of the detected glitches are from Galactic protons incident on the die frame supporting the micro-machined bolometric detectors. In the Planck orbit at L2, the particle flux is around 5 cm −2 s −1 and is dominated by protons incident on the spacecraft with energy >39 MeV, at a rate of typically one event per second per detector. Different categories of glitches have different signatures in the time stream. Two of the glitch types have a low amplitude component that decays over nearly 1 s. This component produces 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 subtraction method removes excess noise from the time streams. Using realistic simulations, we find that this method does not introduce signal bias into the Planck data.

Kinetic Inductance Detectors for the OLIMPO experiment: in-flight operation and performance

“…For this reason the dead time due to CR events is usually smaller than in bolometric detectors, where the time constant is in the 10 ms range (see e.g. [32,33]).…”

Thermal Simulations of Temperature Excursions on the Athena X-IFU Detector Wafer from Impacts by Cosmic Rays

“…These protons will penetrate the spacecraft and create secondary particles, depositing energy wherever they go: the detectors, the wafer, or other mechanical structures. This effect becomes significant at this level of instrument sensitivity, as was the case with the Planck Space mission [3]. This manuscript focusses specifically on the frequent impacts by CRs into the detector wafer, which create a baseline thermal fluctuation seen by the detectors, and whether the level of these fluctuations will affect the energy resolution of the instrument.…”

Particle Response of Antenna-Coupled TES Arrays: Results from SPIDER and the Laboratory

“…The high rate (∼1 Hz) and long recovery times (as long as ∼2 s) of cosmic ray glitches led to significant analysis challenges and data loss [12]. Careful analyses of flight and laboratory data [13,14,12] led to successful cosmological analysis and elucidated several glitch classes corresponding to energy depositions in different regions of the detector assembly. Cosmic ray response is thus a key performance consideration for future space-based bolometric instruments, which will face the added complications of large shared wafers and crosstalk within multiplexed readout wiring.…”

“…To calibrate expectations, we make a crude estimate of the cosmic ray response of a SPIDER detector array by combining Planck 's estimated cosmic ray flux (∼5/cm 2 /s above 40 MeV [12]) and the stopping power of a minimum-ionizing particle. This suggests typical energy depositions in the bolometer island of order a few hundred eV every ∼10 minutes, with perhaps a similar rate on the suspension legs; a more detailed Monte Carlo model incorporating realistic incident energies and particle showers is left to future work.…”