Talk:Charge radius

Other Nuclides

The article really only focuses on the proton, but there are all the other nuclides to consider. Here is a link to a resource for those: www-nds.iaea.org/publications/indc/indc-hun-0033.pdf‎ Perhaps someone who is good at html editing can tidy up the insertion on the main page. Thank you John Pons (talk) 07:26, 30 August 2013 (UTC)

What determines the charge radius?

This article never really comes out and says in clear language how the charge radius is defined. Is there a certain value of electric field (e.g. 10% of the charge of an electron) that defines the radius? What does it mean for an electron to "see" a cross-section? Why is there variation in such? There must be something by which an outermost radius is "seen" or else the average would be arbitrarily high; how is that explained? Perhaps a diagram would be helpful. - Beland (talk) 17:01, 11 August 2016 (UTC)

The rms charge radius $R$ is defined from the mean of the cross-section $\propto r^{2}$, weighted by the charge density $\rho (r)$, so something like

$<R^{2}>={\frac {\int _{r}\rho (r)r^{2}{\rm {d}}{\mathbf {r} }}{\int _{r}\rho (r){\rm {d}}{\mathbf {r} }}}$ 202.140.199.194 (talk) 08:12, 5 June 2020 (UTC)

r₀

where the empirical constant r0 of 1.2–1.5 fm can be interpreted as the proton radius

It is not the proton radius rp = 8,751e-16 but it is rather the Compton wavelength of the proton λC.p = 1,32140985396e-15. Neither is mentioned in the linked article by Weisskopf. Ra-raisch (talk) 15:50, 12 January 2019 (UTC) The number R = 7,5 given in the book probably gives the measured radius of gold and not based upon the mentioned r₀ = 1,33 (which differs for all atoms in the book). Ra-raisch (talk) 16:23, 12 January 2019 (UTC)