  The Crab-like SNR G21.5-0.9 was observed in the X-ray band (0.5-10 keV) by
the XMM-Newton satellite for over 100 ks. The large effective area of the EPIC
instrument has allowed us to to perform a deep search for pulsations from the
central core of G21.5-0.9. No pulsations were found with upper limits on the
pulsed fraction between 7.5 % and 40 % (depending on frequency and energy
range).
