A negative muon beam has been directed on adjacent solid layers of hyd
rogen and neon. Three targets differing by their deuterium concentrati
on were investigated. Muonic hydrogen atoms can drift to the neon laye
r where the muon is immediately transferred. The time structure of the
muonic neon X-rays follows the exponential law with a disappearance r
ate corresponding to the one of mu-p atoms in each target. The rates l
ambda(ppmu) and lambda(pd) can be extracted