Precision measurement of the double quantum transition 32S12−32D52 in hydrogen

By observing the $\text{3}{}^2\text{S}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{(F =0) – 3}{}^2\text{D}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{(F = 2)}$ double quantum transition in a fast beam of atomic hydrogen, we have found for the $\text{3}{}^2\text{S}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{– 3}{}^2\text{D}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}$ interval the value 4013.152± 0.098 MHz, in satisfactory agreement with QED theory.