The excimer laser started with the observation of a nascent spectral line narrowing at 176 nm  reported in 1971 by Nikolai Basov, V. A. Danilychev and Yu. M. Popov, at the Lebedev Physical Institute in Moscow, using liquid xenon dimer (Xe2) excited by an electron beam. Spurred by this report, a better substantiation of stimulated emission was communicated by H.A. Koehler et.al. in 1972, using high pressure Xenon gas. Definitive evidences of a xenon excimer laser action at 173 nm using a high pressure gas at 12 atmospheres, pumped also by an electron beam, were presented for the first time in March 1973  by Mani Lal Bhaumik of Northrop Corporation, Los Angeles. Spectral line narrowing from a continuum of 15 nm to just 0.25 nm and a thousand fold increase in intensity along with laser power high enough to evaporate part of the mirror coatings, imprinting the mode pattern, left little doubt about the realization of strong stimulated emission. With an estimated output of 1 Joule, the potential of developing high power lasers at short wavelengths was credibly established.