I am searching online the most up-to-date result/data of cmb temperature variation, i.e. $\sqrt{<\Delta T^2>} \mu K$

I sort of know it's of order $10\mu K$ and have seen it on an old first-year COBE data paper: Structure in the COBE differential microwave radiometer first-year maps

Anyone please direct me to the up-to-date paper?

  • $\begingroup$ On what angular scale? $\endgroup$ – Rob Jeffries Oct 14 '16 at 20:34
  • $\begingroup$ @RobJeffries based on any up-to-date experiment results, whatever their resolutions are. $\endgroup$ – HanaKaze Oct 15 '16 at 1:46

The best measurements of the CMB temperature fluctuations come from the Planck satellite.

The size of the fluctuations depends on the angular scale considered and is shown in the plot below (from the ESA Planck website).

CMB temperature fluctuations from Planck

Note the yaxis is in the conventional CMB units of $l(l+1)C_l/2\pi$, see here for an explanation of the CMB power spectrum. The translation to simple temperature fluctuations as a function of angular scale is not straightforward, but the plot below corresponds roughly to rms temperature variations of 20 $\mu$K on large angular scales, rising to $\sim 80\mu$K on 1 degree scales, before falling again.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.