The cascade in muonic deuterium atoms has been investigated experimentally,
employing deeply depleted charge-coupled devices as x-ray detectors. The r
elative x-ray yields for the muonic deuterium transitions K alpha, K beta,
and K gamma and the K alpha/K beta ratios have been measured at densities b
etween 0.0107 and 1.145 of liquid hydrogen density. The results are compare
d with our measurements of the muonic x rays in hydrogen and in liquid-hydr
ogen deuterium mixtures in search for an isotopic effect. A comparison of o
ur results with recent calculations is given.