  The micromegas technology is a promising candidate to replace the forward
muon chambers for the luminosity upgrade of ATLAS. The LHC accelerator
luminosity will be five times the nominal one, increasing background and
pile-up event probability. This requires detector performances which are
currently under study in intensive R&D activities. Aging is one of the key
issues for a high-luminosity LHC application. For this reason, we study the
properties of resistive micromegas detectors under intense X-ray radiation and
under thermal neutrons in different CEA-Saclay facilities. This study is
complementary to those already performed using fast neutrons.
