A magnetic resonance apparatus comprising a superconducting magnet coil
which is disposed in a cryostat, and a refrigerator for cooling the
magnet coil, which comprises a compressor for compressing a working gas,
and a high-pressure line and a low-pressure line between the compressor
and a control valve, which periodically connects the high-pressure line
and the low-pressure line to a connecting line from the control valve to
a cold head of the refrigerator, thereby generating pressure pulses via
the connected working gas, wherein the control valve is mechanically
rigidly connected to the cryostat, is characterized in that one pressure
reservoir is provided in the high-pressure line and/or in the low
pressure line, which is mechanically rigidly connected to the cryostat
and which is connected to the compressor via a mechanically flexible line
section. This permits supply of a working gas to a cold head using a
compressor in such a manner that the artifacts in the NMR signals caused
by the pressure pulses of the working gas are minimized.