A model of diffuse Galactic radio emission from 10 MHz to 100 GHz

By A. D. Oliveira-Costa, Max Tegmark, B. Gaensler, J. Jonas, T. Landecker, P. Reich. 2008

408 citations recorded by the source corpus.

Understanding diffuse Galactic radio emission is interesting both in its own right and for minimizing foreground contamination of cosmological measurements. cosmic microwave background experiments have focused on frequencies ≥ 10 GHz, whereas 21-cm tomography of the high-redshift universe will mainly focus on ≤0.2 GHz, for which less is currently known about Galactic emission. Motivated by this, we present a global sky model derived from all publicly available total power large-area radio surveys, digitized with optical character recognition when necessary and compiled into a uniform format, as well as the new Villa Elisa data extending the 1.42-GHz map to the entire sky. We quantify statistical and systematic uncertainties in these surveys by comparing them with various global multifrequency model fits. We find that a principal component based model with only three components can fit the 11 most accurate data sets (at 10, 22, 45 and 408 MHz and 1.42, 2.326, 23, 33, 41, 61, 94 GHz) to an accuracy around 1-10 per cent depending on frequency and sky region. Both our data compilation and our software returning a predicted all-sky map at any frequency from 10 MHz to 100 GHz are publicly available at http://space.mit.edu/home/angelica/gsm.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/f21ac5b811bc27b48aea89e9d61441d5da60e232

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Citations in the corpus

PAPER-64 CONSTRAINTS ON REIONIZATION: THE 21 cm POWER SPECTRUM AT z = 8.4 (2015, background): “…where 21 cm reionization experiments operate, emission from these foregrounds is brighter than the predicted reionization signal by several orders of magnitude (Santos et al. 2005; Ali et al. 2008; de Oliveira-Costa et al. 2008; Jelić et al. 2008; Bernardi et al. 2009, 2010; Ghosh et al. 2011).”
ALL-SKY INTERFEROMETRY WITH SPHERICAL HARMONIC TRANSIT TELESCOPES (2013, methodology): “However, the Global Sky Model (de Oliveira-Costa et al. 2008) is based on a compilation of maps from 10 MHz to 94 GHz.”
An improved source-subtracted and destriped 408 MHz all-sky map (2014, methodology): “A compilation of large-area radio maps from 10 MHz to 94 GHz was produced by de Oliveira-Costa et al. (2008), who used them to produce a Global Sky Model (GSM) of diffuse Galactic radio emission.”
Reionization and the Cosmic Dawn with the Square Kilometre Array (2012, background): “…et al. (2008) made a first foreground model that includes both Galactic and extragalactic components of the foreground emission (see Figure 15). de Oliveira-Costa et al. (2008) used all publicly available total power radio surveys to obtain all-sky Galactic maps at the desired frequency range.”
The pre-launch Planck Sky Model: a model of sky emission at submillimetre to centimetre wavelengths (2012, methodology): “Also, contrary to the model of de Oliveira-Costa et al. (2008), the PSM is strongly linked to physical models of the Galactic emission processes.”
A simulation-calibrated limit on the H i power spectrum from the GMRT Epoch of Reionization experiment (2013, background): “Unfortunately the 21 cm signal is many orders of magnitude less than foregrounds from Galactic and extragalactic sources at the relevant frequencies (Oh & Mack 2003; de Oliveira-Costa et al. 2008).”
FIRST SEASON MWA EOR POWER SPECTRUM RESULTS AT REDSHIFT 7 (2016, background): “While the latter has been studied by many people and a Global Sky Model (GSM) is readily available (de Oliveira-Costa et al. 2008), the computational obstacle of simulating the instrument response to a full sky diffuse model is yet prohibitive, though under active pursuit (Thyagarajan et al. 2015b).”
THE GALACTIC POSITION DEPENDENCE OF FAST RADIO BURSTS AND THE DISCOVERY OF FRB011025 (2014, methodology): “We compute the position-dependent Tsky at 1.4 GHz using the multi-frequency global sky temperature model of de Oliveira-Costa et al. (2008).”
Foregrounds for observations of the cosmological 21 cm line - I. First Westerbork measurements of Galactic emission at 150 MHz in a low latitude field (2009, background): “In all the radio surveys of the Galaxy, the di ﬀ use emission decreases away from the Galactic plane (see de Oliveira-Costa et al. 2008 for a recent analysis of multi-frequency all-sky data).”
Reionization and Cosmology with 21-cm Fluctuations (2009, background): “The angular fluctuations in the Galactic emission at high latitude are quite small (de Oliveira-Costa et al. 2008) and largely resolve out in interferometric observations.14 However, at arcminute scales extra-galactic radio galaxies produce a confused and highly structured surface of emission that…”
INTENSITY MAPPING WITH CARBON MONOXIDE EMISSION LINES AND THE REDSHIFTED 21 cm LINE (2011, background): “For example, de Oliveira-Costa et al. (2008) find that a principle component model with only three components can fit maps of diffuse Galactic radio emission at frequencies from 10 Mhz to 100 Ghz, suggesting a highly-correlated origin for Galactic foreground emission at these frequencies.”
Hydrogen Epoch of Reionization Array (HERA) (2016, methodology): “This was a conservative value based on estimates of power in spectrally smooth foreground sources (Santos et al. 2005; Ali et al. 2008; de Oliveira-Costa et al. 2008; Jelić et al. 2008; Bernardi et al. 2010) and experience with PAPER dealing with foreground systematics.”
WHAT NEXT-GENERATION 21 cm POWER SPECTRUM MEASUREMENTS CAN TEACH US ABOUT THE EPOCH OF REIONIZATION (2013, methodology): “We assume that there exists one Galactic “cold patch” spanning 6 hours in right ascension suitable for EoR observations, an assumption which is based on measurements from both PAPER and the MWA and on previous models (e.g. de Oliveira-Costa et al. 2008).”
The interstellar cosmic-ray electron spectrum from synchrotron radiation and direct measurements. (2011, background): “The coverage of these surveys can be seen graphically in de Oliveira-Costa et al. (2008)12.”