“…The first experiment to actually use laserbackscattered photons as a beam in a physics measurement was conducted at SLAC in 1969 (Ballam et al, 1969). Many other experiments followed this approach to produce x rays and γ rays (Albert et al, 2010;Anderson et al, 2004;Babzien et al, 2006;Bula et al, 1996;Burke et al, 1997;Glotin et al, 1996;Kotaki et al, 2000;Leemans et al, 1997;Litvinenko et al, 1997;Pogorelsky et al, 2000;Sakai et al, 2003;Sandorfi et al, 1983;Schoenlein et al, 1996;Ting et al, 1995;Yorozu et al, 2003Yorozu et al, , 2001, and nowadays several γ-ray facilities are based on this method.…”