J/A+A/623/A21 Thermal dust modified black-body parameter maps (Irfan+, 2019)
Determining thermal dust emission from Planck HFI data using sparse,
parametric technique.
Irfan M.O., Bobin J., Miville-Deschenes M.A., Grenier I.
<Astron. Astrophys. 623, A21 (2019)>
=2019A&A...623A..21I 2019A&A...623A..21I (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium
Keywords: cosmic microwave background - dust, extinction -
methods: data analysis
Abstract:
The Planck data releases have provided the community with
submillimetre and full-sky radio observations at unprecedented
resolutions. We make use of the Planck 353, 545, and 857GHz maps
alongside the IRAS 3000 GHz map. These maps contain information on the
cosmic microwave background (CMB), cosmic infrared background (CIB),
extragalactic point sources, and diffuse thermal dust emission.
We aim to determine the modified black-body (MBB) model parameters of
thermal dust emission in total intensity and produce all-sky maps of
pure thermal dust, having separated this Galactic component from the
CMB and CIB.
This separation is completed using a new, sparsity-based, parametric
method, Parameter Recovery Exploiting Model Informed Sparse Estimates
(premise). The method is comprised of three main stages: 1) filtering
the raw data to reduce the effect of the CIB on the MBB fit; 2)
fitting an MBB model to the filtered data across super-pixels of
various sizes determined by the algorithm itself; and 3) refining
these super-pixel estimates into full-resolution maps of the MBB
parameters.
We present our maps of MBB temperature, spectral index, and optical
depth at 5-arcmin resolution and compare our estimates to those of
GNILC and to the two-step MBB fit presented by the Planck
collaboration in 2013.
By exploiting sparsity we avoid the need for smoothing, enabling us to
produce the first full-resolution MBB parameter maps from intensity
measurements of thermal dust emission.We consider the premise
parameter estimates to be competitive with the existing
state-of-the-art solutions, outperforming these methods within low
signal-to-noise regions as we account for the CIB without removing
thermal dust emission through oversmoothing.
Description:
Thermal dust modified black-body parameter maps are presented. The
three maps (temperature, spectral index and optical depth at 353GHz)
are given at Nside 2048 with a FWHM of 5 arcmin. Missing (NAN) values
in each map correspond to the Planck PR2 HFI point source masks (the
353, 545 and 857GHz point source masks have multiplied to form a
'total' point source mask).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 86 3 List of fits files
fits/* . 3 Individual fits files
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Nx Number of pixels along X-axis
6- 10 I5 --- Ny Number of pixels along Y-axis
12- 17 I6 Kibyte size Size of FITS file
19- 27 A9 --- FileName Name of FITS file, in subdirectory fits
29- 86 A58 --- Title Title of the FITS file
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Acknowledgements:
Melis Irfan, melis.irfan(at)cea.fr
References:
Irfan & Bodin, Sparse estimation of model-based diffuse thermal dust emission,
2018MNRAS.474.5560I 2018MNRAS.474.5560I
(End) Melis Irfan [CEA, France], Patricia Vannier [CDS] 18-Jan-2019