Raman, C.V.; Bhagavantam, S.; Experimental Proof of the Spin of the Photon
Nature 129 (1932) 22;
In a paper under this title which has recently appeared, we have described and discussed observations which have led us to the conclusion that the light quantum possesses an intrinsic spin equal to one Bohr unit of angular momentum. In the four weeks which have elapsed since that paper was put into print, the experimental technique has been much improved in the direction of attaining greater precision. It appears desirable forthwith to report our newer results, which confirm the conclusion
stated above. (Extracted from the introductory part of the paper.).
Related references More (earlier) information appears in C. V. Raman and S. Bhagavantam, Ind. Jour. Phys. 6 (1931) 353;
C. V. Raman and S. Bhagavantam, Nature 128 (1931) 727;
C. V. Raman and S. Bhagavantam, Nature 128 (1931) 576;
Experimental proof that the photon has spin = 1.