We present the design and measurements on a magnetic shield based on MgB2 integrated in a commercial pulse tube cryostat. The shield is fabricated by an innovative manufacturing process, useful to obtain bulk MgB2 superconductor of high density. The shield is ideal for shielding at cryogenic temperatures lower than 35 K. With respect to the conventional cryogenic superconducting shields, made e.g. by lead foil, the actual MgB2 shield presents the advantages of a very high temperature margin and a lower density (2.4 g/cm3). The last characteristic will be particularly useful in space applications. Furthermore, with a superconducting transition temperature of about 39 K, it is possible to reduce markedly the Earth field trapped during the cool down of thin film based devices fabricated from materials with lower transition temperatures. The shape and the dimensions can be varied according to the needs. The prototype shield has a sample volume with the diameter of 37 mm and the height of 35 mm. As a test for the functionality of the shield we have measured properties of a SQUID magnetic field sensor showing significant reduction of ambient magnetic noise and interference. The shielding capability of the present MgB2 cup are reviewed and the possible applications of these line of products will be discussed.

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