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Title: Cleaning our own dust: simulating and separating galactic dust foregrounds with neural networks
ABSTRACT Separating galactic foreground emission from maps of the cosmic microwave background (CMB) and quantifying the uncertainty in the CMB maps due to errors in foreground separation are important for avoiding biases in scientific conclusions. Our ability to quantify such uncertainty is limited by our lack of a model for the statistical distribution of the foreground emission. Here, we use a deep convolutional generative adversarial network (DCGAN) to create an effective non-Gaussian statistical model for intensity of emission by interstellar dust. For training data we use a set of dust maps inferred from observations by the Planck satellite. A DCGAN is uniquely suited for such unsupervised learning tasks as it can learn to model a complex non-Gaussian distribution directly from examples. We then use these simulations to train a second neural network to estimate the underlying CMB signal from dust-contaminated maps. We discuss other potential uses for the trained DCGAN, and the generalization to polarized emission from both dust and synchrotron.
Authors:
; ; ; ;
Award ID(s):
1812199 1560482 1852581
Publication Date:
NSF-PAR ID:
10253855
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
500
Issue:
3
Page Range or eLocation-ID:
3889 to 3897
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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