We investigate the effectiveness of the statistical radio frequency interference (RFI) mitigation technique spectral kurtosis (
This content will become publicly available on March 29, 2025
The growth of supermassive black holes is strongly linked to their galaxies. It has been shown that the population mean black hole accretion rate (
 Award ID(s):
 2106990
 NSFPAR ID:
 10522735
 Publisher / Repository:
 The Astrophysical Journal
 Date Published:
 Journal Name:
 The Astrophysical Journal
 Volume:
 964
 Issue:
 2
 ISSN:
 0004637X
 Page Range / eLocation ID:
 183
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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Abstract ) in the face of simulated realistic RFI signals. $\widehat{\mathit{SK}}$ estimates the kurtosis of a collection of $\widehat{\mathit{SK}}\phantom{\rule{0.25em}{0ex}}$M power values in a single channel and provides a detection metric that is able to discern between humanmade RFI and incoherent astronomical signals of interest. We test the ability of to flag signals with various representative modulation types, data rates, duty cycles, and carrier frequencies. We flag with various accumulation lengths $\widehat{\mathit{SK}}\phantom{\rule{0.25em}{0ex}}$M and implement multiscale , which combines information from adjacent timefrequency bins to mitigate weaknesses in singlescale $\widehat{\mathit{SK}}$ . We find that signals with significant sidelobe emission from high data rates are harder to flag, as well as signals with a 50% effective duty cycle and weak signaltonoise ratios. Multiscale $\widehat{\mathit{SK}}$ with at least one extra channel can detect both the center channel and sideband interference, flagging greater than 90% as long as the bin channel width is wider in frequency than the RFI. $\widehat{\mathit{SK}}$ 
Abstract We measure the thermal electron energization in 1D and 2D particleincell simulations of quasiperpendicular, lowbeta (
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