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High Resolution Microwave Full Sky Simulations
Overview

Here are realistic, full-sky, half-arcminute resolution simulations of the microwave sky matched to many recent astrophysical observations. The maps utilize the easily accessible HEALPix format to make these simulations applicable to many current and near future microwave background experiments.

Some of the novel features of these simulations are that the radio and infrared galaxy populations are correlated with the galaxy cluster and group populations, the primordial microwave background is lensed by the dark matter structure in the simulation via a ray-tracing code, the contribution to the thermal and kinetic Sunyaev-Zel'dovich (SZ) signals from galaxy clusters, groups, and the intergalactic medium has been included, and the gas prescription to model the SZ signals has been refined to match the most recent X-ray observations.

The cosmology adopted in these simulations is also consistent with the WMAP 5-year parameter measurements. These simulations should serve as a useful tool for microwave surveys to cross-check SZ cluster detection, power spectrum, and cross-correlation analyses.

Here is an update of the Seghal et al. (2010) simulations below. The changes are that 1.) the extragalactic CIB and thermal SZ component have been scaled down to better match some current observations, 2.) a flux cut of 7 mJy at 150 GHz has been applied to all radio source maps, 3.) low-frequency Galactic foregrounds (Synchrotron, Free-Free, AME) have been added based on the Planck Commander analysis, but at lower resolution than the other components (~0.5 deg), 4.) the maps now span 13 frequencies between 27 and 353 GHz, 5.) the maps are at a resolution of Nside=4096 (1 arcminute), and 6.) are in units of uK, unless otherwise specified in the README file. These updates/revisions were made by J. Colin Hill. Any questions may be sent to jcolin.hill@gmail.com and Neelima Sehgal at neelima.sehgal@stonybrook.edu. These simulations were used in the Simons Observatory Science Goals and Forecast paper, where additional details can be found (https://arxiv.org/abs/1808.07445).

Sky Maps, Simons Observatory Forecasts (2019)
Map Type Frequency [GHz]
27 30 39 44 70 93 100 143 145 217 225 280 353 All
Cosmic Infrared Background (CIB) CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map CIB Sky Map All CIB Sky Map
Radio Sources Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map Radio Sources Sky Map All Radio Sources Sky Map
Galactic Dust Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map Galactic Dust Sky Map All Galactic Dust Sky Map
Low-Frequency Galactic Foregrounds L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map L-F Galactic Foregrounds Sky Map All L-F Galactic Foregrounds Sky Map
Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps Total Maps All Kinetic SZ Sky Maps
All All  27GHz Sky Maps All  30GHz Sky Maps All 39GHz Sky Maps All 44GHz Sky Maps All 70GHz Sky Maps All 93GHz Sky Maps All 100GHz Sky Maps All 143GHz Sky Maps All 145GHz Sky Maps All 217GHz Sky Maps All 225GHz Sky Maps All 280GHz Sky Maps All 353GHz Sky Maps
Please note that these links point directly at binary files; you should right click on the links and select the "Save link as" option. Each green dot represents a single map for the corresponding data type/frequency pair; each map is 3GB in size. The blue squares point to compressed tarballs containing all the maps in the corresponding column or row. More information...

CMB and SZ Maps, Simons Observatory Forecasts (2019)
Maps Description
Lensed CMB This is the lensed CMB temperature map, in units of uK (this map is frequency-independent in the thermodynamic CMB temperature units used here). More information...
CMB Lensing Convergence This is the CMB lensing convergence (kappa) map, with which the CMB temperature field is lensed. It is computed via the Born approximation, i.e., no ray-tracing is performed. More information...
Kinematic SZ This is the kSZ map, in units of uK (although the filename has '148', this map is frequency-independent in the thermodynamic CMB temperature units used here). More information...
Thermal SZ This is the tSZ map, in units of Compton-y (dimensionless), with the rescaling factor applied to bring the amplitude of the power spectrum into reasonable agreement with the Planck 2013 y-map tSZ power spectrum. Note that the user must rescale this map to each frequency by multiplying by the tSZ spectral function and T_CMB=2.726e6 uK. More information...

CMB and SZ power spectra, Simons Observatory Forecasts (2019)
Power Spectra Description
CMB_PS_healpix_Nside4096_DeltaT_uK_SimLensCMB.txt This is the power spectrum of the lensed CMB temperature map, in units of uK^2 (with no factors of ell, 2pi, etc.). More information...
kSZ_PS_Sehgal_healpix_Nside4096_DeltaT_uK.txt This is the power spectrum of the kSZ map, in units of uK^2 (with no factors of ell, 2pi, etc.). More information...
Sehgal_sim_tSZPS_unbinned_8192_y_rescale0p75.txt This is the power spectrum of the tSZ map, in units of Compton-y (dimensionless) (with no factors of ell, 2pi, etc.), with the rescaling factor applied to bring the amplitude into reasonable agreement with the Planck 2013 y-map tSZ power spectrum. More information...

The halo and galaxy catalogs provided here are unchanged from the original versions. Note that to match the rescaling of the CIB and thermal SZ components in the updated maps the thermal SZ signals in the halo files and fluxes in the IR galaxy files should be rescaled (multiplied) by a factor of 0.75. See Section 2.4.1 of https://arxiv.org/abs/1808.07445 for more details.

Catalogs, Sehgal et al. (2010)
Catalog Description
Low-Mass Halo (ascii) Basic halo properties of halos with Mfof > 6.82 x 1012 Msun/h and with Mfof < 2 x 1013 Msun/h. More information...
Low-Mass Halo Same as above in binary. More information...
N-Body Halo (ascii) Basic halo properties of halos with Mfof > 2 x 1013 Msun/h. More information...
N-Body Halo Same as above in binary. More information...
SZ Halo (ascii) Halo properties, including SZ characteristics, for all the halos with Mfof > 2 x 1013 Msun/h. More information...
SZ Halo Same as above in binary. More information...
IR Galaxies Catalog of the basic population of infrared galaxies. More information...
High-Flux IR Galaxies Catalog of the very high flux infrared galaxies. More information...
Radio Galaxies Catalog of the radio galaxies. More information...

The maps below are from the original simulations described by Sehgal et al. (2010).

Sky Maps, Sehgal et al. (2010)
Map Type Frequency [GHz]
30 90 148 219 277 350 All
Unlensed CMB Unlensed CMB  30GHz Sky Map Unlensed CMB  90GHz Sky Map Unlensed CMB 148GHz Sky Map Unlensed CMB 219GHz Sky Map Unlensed CMB 277GHz Sky Map Unlensed CMB 350GHz Sky Map All Unlensed CMB Sky Maps
Lensed CMB Lensed CMB  30GHz Sky Map Lensed CMB  90GHz Sky Map Lensed CMB 148GHz Sky Map Lensed CMB 219GHz Sky Map Lensed CMB 277GHz Sky Map Lensed CMB 350GHz Sky Map All Lensed CMB Sky Maps
Thermal SZ Thermal SZ  30GHz Sky Map Thermal SZ  90GHz Sky Map Thermal SZ 148GHz Sky Map Thermal SZ 219GHz Sky Map Thermal SZ 277GHz Sky Map Thermal SZ 350GHz Sky Map All Thermal SZ Sky Maps
Kinetic SZ Kinetic SZ  30GHz Sky Map Kinetic SZ  90GHz Sky Map Kinetic SZ 148GHz Sky Map Kinetic SZ 219GHz Sky Map Kinetic SZ 277GHz Sky Map Kinetic SZ 350GHz Sky Map All Kinetic SZ Sky Maps
Full SZ Full SZ  30GHz Sky Map Full SZ  90GHz Sky Map Full SZ 148GHz Sky Map Full SZ 219GHz Sky Map Full SZ 277GHz Sky Map Full SZ 350GHz Sky Map All Full SZ Sky Maps
Radio Galaxies Radio Galaxies  30GHz Sky Map Radio Galaxies  90GHz Sky Map Radio Galaxies 148GHz Sky Map Radio Galaxies 219GHz Sky Map Radio Galaxies 277GHz Sky Map Radio Galaxies 350GHz Sky Map All Radio Galaxies Sky Maps
Infrared Galaxies Infrared Galaxies  30GHz Sky Map Infrared Galaxies  90GHz Sky Map Infrared Galaxies 148GHz Sky Map Infrared Galaxies 219GHz Sky Map Infrared Galaxies 277GHz Sky Map Infrared Galaxies 350GHz Sky Map All Infrared Galaxies Sky Maps
Galactic Dust Dust  30GHz Sky Map Dust  90GHz Sky Map Dust 148GHz Sky Map Dust 219GHz Sky Map Dust 277GHz Sky Map Dust 350GHz Sky Map All Dust Sky Maps
Combined Sky Map Combined  30GHz Sky Map Combined  90GHz Sky Map Combined 148GHz Sky Map Combined 219GHz Sky Map Combined 277GHz Sky Map Combined 350GHz Sky Map All Combined Sky Maps
All All  30GHz Sky Maps All  90GHz Sky Maps All 148GHz Sky Maps All 219GHz Sky Maps All 277GHz Sky Maps All 350GHz Sky Maps All Sky Maps

Please note that these links point directly at binary files; you should right click on the links and select the "Save link as" option. Each green dot represents a single map for the corresponding data type/frequency pair; each map is 3GB in size. The blue squares point to compressed tarballs containing all the maps in the corresponding column or row; the blue dot in the lower right corner points to a tarball containing all the maps. More information...

A service of the HEASARC and of the Astrophysics Science Division at NASA/GSFC
Goddard Space Flight Center, National Aeronautics and Space Administration
HEASARC Director: Dr. Alan P. Smale
LAMBDA Director: Dr. Eric R. Switzer
NASA Official: Dr. Eric R. Switzer
Web Curator: Mr. Michael R. Greason