  With the data collected by LHC at 13 TeV, the CMS collaboration has searched
for low mass resonances decaying into two photons. This has resulted in the
observation of 3 sd excess around 95 GeV, reminiscent of an indication obtained
at LEP2 by combining the Higgs boson searches of the four LEP experiments.
These observations, marginally significant, motivate the present study which
shows how HL-LHC and ILC250 could search for a radion, the lightest new
particle predicted within the Randall Sundrum (RS) model. ILC operating at a
centre of mass energy of 250 GeV and with an integrated luminosity surpassing
LEP2 by three orders of magnitude, could become the ideal machine to study a
light radion and to observe, with very high accuracy, how it mixes with the
Higgs boson and modifies the various couplings.
