Charging method for a superconductor magnet system with reduced stray field, weight and space includes: arranging the system within a charger magnet bore; with T.sub.main>T.sub.main.sup.crit and T.sub.shield>T.sub.shield.sup.crit, applying a current I.sub.charger to the charger magnet and increasing I.sub.charger to a first current I.sub.1>0; lowering a main superconductor bulk magnet temperature T.sub.main to an operation temperature T.sub.main.sup.op, with T.sub.main.sup.op<T.sub.main.sup.crit, while keeping T.sub.shield>T.sub.shield.sup.crit; lowering I.sub.charger to a second current I.sub.2<0, thereby inducing a persistent current IP.sub.main in the main magnet; lowering a shield magnet temperature T.sub.shield to an operation temperature T.sub.shield.sup.op, with T.sub.shield.sup.op<T.sub.shield.sup.crit; increasing I.sub.charger to zero, thereby inducing a persistent current IP.sub.shield in the shield magnet; removing the magnet system from the charger bore, and keeping T.sub.main≤T.sub.main.sup.op with T.sub.main.sup.op<T.sub.main.sup.crit and T.sub.shield≤T.sub.shield.sup.op with T.sub.shield.sup.op<T.sub.shield.sup.crit; where: T.sub.main.sup.crit: main magnet critical temperature and T.sub.shield.sup.crit: shield magnet critical temperature.

A superconductor magnet apparatus (2) includes a superconductor bulk magnet (9), a cryostat (7) and a ferromagnetic shielding body (11). The bulk magnet has a superconductor bore (10), an axis (z) of rotational symmetry, and a maximum outer diameter OD.sub.bm in a plane perpendicular to the z axis. The superconductor bore has a minimum cross-sectional area S.sub.bo in a plane perpendicular to the z axis. The cryostat has a room temperature bore (8), the bulk magnet is arranged within the cryostat and the room temperature bore is arranged within the superconductor bore. The shielding body has a shielding bore (12), the bulk magnet is arranged within the shielding bore and the shielding body extends beyond the bulk magnet at each axial end by at least OD.sub.bm/3. For an average cross-sectional area S.sub.fb of the shielding body, S.sub.fb≥2.5*S.sub.bo, and the shielding body is arranged within the cryostat.

A superconducting magnet may include magnet coils including at least one group of outer coils and at least one group of inner coils, a container including an accommodating space, at least one first chamber that is disposed within the accommodating space and houses the at least one group of the inner coils, and at least one second chamber that is disposed within the accommodating space and houses the at least one group of the outer coils. The at least one first chamber and the at least one second chamber may be configured to be filled with a cooling medium and are in fluid communication with each other. The cooling medium may be configured to cool the magnet coils to a superconducting state.

A technique relates to a superconducting chip. Resonant units have resonant frequencies, and the resonant units are configured as superconducting resonators. Josephson junctions are in the resonant units, and one or more of the Josephson junctions have a shorted tunnel barrier.

A superconducting magnet includes a vacuum vessel (20), a liquid helium vessel (14) disposed in the vacuum vessel, and superconducting magnet windings (12) disposed in the liquid helium vessel. A thermal shield (22, 24) is spaced apart from and at least partly surrounds the liquid helium vessel. A thermal battery (30) is disposed in the vacuum vessel and is in thermally conductive contact with the thermal shield. The thermal battery may comprise a sealed container (32) in thermally conductive contact with the thermal shield and containing a working fluid such as nitrogen, and may contain a porous material (34). In operation, when active cooling of the magnet is turned off, the thermal battery slows the warming of the magnet by way of absorption of latent heat by the working fluid undergoing a solid-to-liquid or liquid-to-gas phase change.

A magnetic resonance apparatus, for acquiring magnetic resonance data from a person who is asleep, includes a person support apparatus to provide a sleeping place; an acquisition arrangement including a radiofrequency coil arrangement for transmitting excitation pulses and for receiving magnetic resonance signals; and a controller, designed to operate the acquisition arrangement according to a magnetic resonance sequence for acquiring a magnetic resonance dataset from a region under examination of the person. The magnetic resonance apparatus includes a main magnetic field of strength less than 20 mT, in particular less than 10 mT, and the controller includes an acquisition unit for acquiring a magnetic resonance dataset via a prolonged magnetic resonance sequence having a total acquisition duration of more than one hour.

The present disclosure provides a magnetic resonance imaging (MRI) device. The MRI device may include a main magnet configured to generate a main magnetic field. The main magnet may form an accommodation space configured to accommodate a target object. The main magnet may include at least one group of main field coils. A direction of the main magnetic field generated by the at least one group of main field coils may form a preset angle with an axial direction of the accommodation space. The at least one group of main field coils may include a first group of main field coils and a second group of main field coils that are arranged oppositely along a radial direction of the accommodation space. Each of the first group of main field coils and the second group of main field coils may bend towards each other.

An asymmetric magnet for use in performing MRI of a patient's head. The magnet has a patient end. The magnet provides an offset imaging volume (35) in a recess with an isocentre that is positioned closer to the patient end than an opposite end. The magnet has at least three groups of coils (44, 45, 46) in a generally tapering arrangement. The magnet also has an additional group of coils (47). A first group of coils (44) overlaps the additional group of coils (47), such that a bottom portion (47) of the additional group of coils (47) is positioned closer to the patient end of the magnet than a top portion (44) of the first group of coils (44).

An energy delivery system includes a transmission member, an antenna at a distal end of the transmission member, a jacket surrounding the transmission member and the antenna, a fluid channel between the transmission member and the jacket, and a plug disposed at the distal end of the transmission member and a proximal end of the antenna. The plug is configured to prevent migration of a cooling fluid from the fluid channel to a cavity between the antenna and the jacket.

An imaging device may include multiple magnetic coils to generate a magnetic field. Additionally, the imaging device may include an outer support affixed to at least one coil of the plurality of magnetic coils and an axial support between at least two coils of the plurality of magnetic coils, wherein the outer support and the axial support operatively share a load corresponding to the generated magnetic fields.