Max Tegmark's CMB analysis center: EXPERIMENTS

This site contains up-to-date links to cosmic microwave background (CMB) resources across the globe, focusing on data analysis. For theoretical aspects, see e.g. Wayne Hu's theory center.

Experimental data summary

(Feb 2004) New CBI and VSA results!

This figure summarizes the experimental results as of February 23 2004. Click on it for a postscript version. If you find this too cluttered, here's a combination of WMAP, CBI, ACBAR, BOOM, DASI, MAXIMA & VSA as per January 2004 taking into account calibration and beam errors as described in this paper:

(click on it for ps). I've removed all other experiments from the compilation because they make essentially no difference to the combined plot above, and because the approximation that they are independent of WMAP breaks down except for experiments with small sky coverage on small angular scales. Nostalgic readers will find all the old data here: gif, ps. Here are text files with the corresponding data, window functions and correlation matrix (haven't yet had time to update these including WMAP - sorry). To use these window functions, make sure to read the definition here to avoid confusion about an extra l-factor etc.

(9/19/02) DASI detects polarization! (Sorry - haven't added WMAP polarization detection yet.)

Click on the plot for a postscript version.
You'll also find useful data compilations on the websites of Eric Gawiser and Lloyd Knox. Please send additions and corrections to I used to have a big yellow table here with all the numbers - I've removed it since it's superseded by the above-mentioned text files and was hard to cut and paste from.

Foreground summary

This figure summarizes the angular and frequency sensitivity of various experiments. Click on it for a postscript version. For foreground software and data tables (including polarization), please check out my foreground page here, our WMAP foreground paper and our monster review. Please send the specifications for missing ones to (Currently, e.g., TOP HAT, MAXIMA and BEAST are unfortunately omitted from the figure above simply since they make it too cluttered.) For future multichannel experiments, the crude boxes have been replaced by polygons, the highest l-value at each channel being that at which noise dominates over sample variance (see Knox 1995 or Tegmark & Efstathiou 1996). exp(theta^2 l^2)/w equals that of Qflat=20 microkelvin CMB fluctuations. Likewise, the colored regions show where fluctuations in various foregrounds are expected to exceed those of Qflat=20 microkelvin CMB fluctuations in the cleanest 20% of the sky. The foregrounds are dust (red), point-sources (green), synchrotron (magenta) and free-free emission (cyan), and the estimates are based on Tegmark & Efstathiou 1996. Needless to say, one can perform successful CMB measurements outside of the white region as well, with appropriate foreground removal schemes. 

Links to CMB Experiments

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Other CMB links:

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