EP2367404B1 - Device for reducing the heating of a vacuum chamber - Google Patents

Device for reducing the heating of a vacuum chamber Download PDF

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Publication number
EP2367404B1
EP2367404B1 EP11001598.9A EP11001598A EP2367404B1 EP 2367404 B1 EP2367404 B1 EP 2367404B1 EP 11001598 A EP11001598 A EP 11001598A EP 2367404 B1 EP2367404 B1 EP 2367404B1
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Prior art keywords
vacuum chamber
strips
superconducting
particle beam
superconductive
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EP11001598.9A
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German (de)
French (fr)
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EP2367404A3 (en
EP2367404A2 (en
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Robert Dr. Rossmanith
Daniel Dr. Wollmann
Axel Dr. Bernhard
Peter Peiffer
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Karlsruher Institut fuer Technologie KIT
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Karlsruher Institut fuer Technologie KIT
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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H7/00—Details of devices of the types covered by groups H05H9/00, H05H11/00, H05H13/00
    • H05H7/14—Vacuum chambers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F6/00—Superconducting magnets; Superconducting coils
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H7/00—Details of devices of the types covered by groups H05H9/00, H05H11/00, H05H13/00
    • H05H7/04—Magnet systems, e.g. undulators, wigglers; Energisation thereof

Definitions

  • the invention relates to a device for reducing the heating of a vacuum chamber, which is intended to receive a charged particle beam, which is incident on a magnetic field emanating from a superconducting magnet, in particular in an accelerator, and a vacuum chamber comprising such a device.
  • Modern accelerators include undulators or wigglers that include superconducting magnets that serve to impinge a charged particle beam that is typically in a vacuum chamber at helium temperature.
  • the particle beam heats the vacuum chamber through numerous effects.
  • the most common cause of the heating is that mirror charges are induced in the walls of the cold but non-superconducting vacuum chamber and travel with the particle beam. Due to the finite ohmic resistance, the currents generated thereby heat the metallic wall of the vacuum chamber and thus indirectly both the superconducting magnet and the vacuum chamber.
  • the accelerator is constructed so that there is no metallic wall between the superconducting magnet and the particle beam, the mirror charges traveling with the particle beam are induced directly into the metallic surfaces of the magnet.
  • the currents generated thereby due to the finite ohmic resistance heat the surfaces and thus indirectly the superconducting magnet and the vacuum chamber.
  • a device which is provided for receiving a particle beam (electron beam), wherein between the particle beam and a superconducting magnet (lens coil winding) is a cup-shaped shielding device made of superconducting material.
  • a particle beam electron beam
  • a superconducting magnet coil winding
  • the US 3,290,219 A , the WO 2007/122025 A1 and the DE 10 2006 027 218 A1 disclose other devices for receiving charged particle beams, which are surrounded by a plurality of superconducting magnets or in which a superconducting material is incorporated in a normal conducting coil to prevent the heating of the coil, which results in the production of mirror charges.
  • the object of the present invention is to provide a device for reducing the heating of a vacuum chamber, which is provided for receiving a charged particle beam in an accelerator, and a vacuum chamber,
  • such a device is to be provided which makes it possible for the magnetic field emanating from a superconducting magnet to strike the charged particle beam passing through the vacuum chamber as unhindered as possible.
  • the device according to the invention has a multiplicity of superconducting strips which are arranged between the charged particle beam and the superconducting magnet.
  • the superconducting strips are each arranged parallel to one another in at least one row.
  • the strips are arranged parallel to the beam direction of the particle beam.
  • the superconducting strips are distributed over at least two separate rows, which are spatially offset from one another.
  • the superconducting strips in the at least two rows are such offset from one another, that these, viewed from the particle beam, cover the largest possible area.
  • the plurality of superconducting strips is arranged in such a way that the charged particle beam "sees" a superconducting surface that is as homogeneous and as closed as possible, but that the magnetic field passes through the plurality of superconducting strips as unhindered as possible.
  • the thickness of the superconducting strips preferably assumes a value in the range of 100 nm to 1 ⁇ m.
  • the plurality of superconductive strips are deposited on a support disposed between the charged particle beam and the superconducting magnet.
  • the carrier consists of a solid, metallic or preferably insulating material.
  • the thickness of the support is preferably 10 ⁇ m to 1000 ⁇ m.
  • superconducting strips are respectively applied to the two sides of the carrier in such a way that the strips are applied offset on one side in relation to the strips on the other side.
  • the invention further relates to a vacuum chamber, in particular in an accelerator, for receiving a charged particle beam, on which a magnetic field emanating from a superconducting magnet impinges, which is equipped with a device according to the invention.
  • a superconductor is a diamagnet
  • the magnetic field lines in a so-called type I superconductor are completely displaced or in a so-called type II superconductor partially displaced, so that a superconducting vacuum chamber prevents heating by the mirror currents, but at the same time for the Reduce or eliminate the magnetic field required by the charged particle beam.
  • Such a reduction of the field strength by a thin superconducting layer of a type II superconductor could be detected experimentally.
  • the reduction of the magnetic field is prevented by the fact that the side facing the particle beam is indeed composed of a superconducting layer, but this layer is interrupted in strip form.
  • the field lines are deflected according to the diamagnetic behavior of the superconductor in each case to the superconducting strips and attenuated in this way only very slightly.
  • the device of the invention makes it possible to reduce the heating of a vacuum chamber by largely avoiding the formation of mirror currents in the wall of the vacuum chamber or the surface of the magnet, wherein the magnetic field passes through the plurality of superconducting strips largely unhindered, and is therefore suitable for the Use in vacuum chambers, especially in accelerators.
  • Fig. 1 shows a device according to the invention, which is designed in the form of arranged in a row superconducting strips 3, 3 ' in a vacuum chamber.
  • Fig. 2 is a device according to the invention, as in Fig. 1 in a vacuum chamber in the form of arranged in a row superconducting strips 3, 3 ' on an insulating support 6 is shown.
  • Fig. 3 shows an inventive device, which is in a vacuum chamber in the form of arranged in two separate rows superconducting strips 3, 3 ' and 4, 4', 4 "is executed.
  • Fig. 4 is a device according to the invention, as in Fig. 3 in a vacuum chamber in the form of arranged in two separate rows superconducting strips 3, 3 ' and 4, 4' , 4 ", which are located respectively on opposite side of the insulating support 6 , is shown.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Optics & Photonics (AREA)
  • Power Engineering (AREA)
  • Particle Accelerators (AREA)

Description

Die Erfindung betrifft eine Vorrichtung zur Verringerung der Erwärmung einer Vakuumkammer, die zur Aufnahme eines geladenen Teilchenstrahls, auf den ein von einem supraleitenden Magneten ausgehendes Magnetfeld auftrifft, insbesondere in einem Beschleuniger vorgesehen ist, sowie eine Vakuumkammer, die eine derartige Vorrichtung umfasst.The invention relates to a device for reducing the heating of a vacuum chamber, which is intended to receive a charged particle beam, which is incident on a magnetic field emanating from a superconducting magnet, in particular in an accelerator, and a vacuum chamber comprising such a device.

Moderne Beschleuniger enthalten Undulatoren oder Wiggler, die supraleitende Magnete umfassen, die zur Beaufschlagung eines geladenen Teilchenstrahls, der sich in einer Vakuumkammer in der Regel auf Helium-Temperatur befindet, dienen.Modern accelerators include undulators or wigglers that include superconducting magnets that serve to impinge a charged particle beam that is typically in a vacuum chamber at helium temperature.

Der Teilchenstrahl erwärmt die Vakuumkammer über zahlreiche Effekte. Die üblicherweise stärkste Ursache für die Erwärmung besteht darin, dass in den Wänden der kalten, aber nicht supraleitenden Vakuumkammer Spiegelladungen induziert werden, die mit dem Teilchenstrahl wandern. Die dadurch erzeugten Ströme erwärmen aufgrund des endlichen Ohmschen Widerstands die metallische Wand der Vakuumkammer und damit indirekt sowohl den supraleitenden Magneten als auch die Vakuumkammer.The particle beam heats the vacuum chamber through numerous effects. The most common cause of the heating is that mirror charges are induced in the walls of the cold but non-superconducting vacuum chamber and travel with the particle beam. Due to the finite ohmic resistance, the currents generated thereby heat the metallic wall of the vacuum chamber and thus indirectly both the superconducting magnet and the vacuum chamber.

Ist der Beschleuniger so aufgebaut, dass sich zwischen dem supraleitenden Magneten und dem Teilchenstrahl keine metallische Wand befindet, werden die Spiegelladungen, die mit dem Teilchenstrahl wandern, direkt in die metallischen Oberflächen des Magneten induziert. Auch hier erwärmen die dadurch erzeugten Ströme aufgrund des endlichen Ohmschen Widerstands die Oberflächen und damit auch hier indirekt den supraleitenden Magneten und die Vakuumkammer.If the accelerator is constructed so that there is no metallic wall between the superconducting magnet and the particle beam, the mirror charges traveling with the particle beam are induced directly into the metallic surfaces of the magnet. Here, too, the currents generated thereby due to the finite ohmic resistance heat the surfaces and thus indirectly the superconducting magnet and the vacuum chamber.

Weitere Quellen für die Erwärmung der Vakuumskammer sind die Synchrotronstrahlung, die auf die kalte Vakuumkammer fällt, bzw. ein Bombardement der Vakuumkammer durch Elektronen oder Ionenwolken. Jede Erwärmung des Magneten oder des Supraleiters verringert den maximalen Strom im Supraleiter und somit das erreichbare maximale Magnetfeld. Darüber hinaus ist auch die Erwärmung des Volumens der Vakuumkammer unerwünscht.Further sources of heat for the vacuum chamber are the synchrotron radiation falling on the cold vacuum chamber or a bombardment of the vacuum chamber by electrons or Ion clouds. Each heating of the magnet or the superconductor reduces the maximum current in the superconductor and thus the maximum magnetic field achievable. In addition, the heating of the volume of the vacuum chamber is undesirable.

Aus S. Khrushchev, V. Lev, N. Mezentsev, E. Miginsky, V. Repkov, V. Shkaruba, V. Syrovatin, V. Tsukanov, 3.5 Tesla 49-pole superconducting wiggler for DLS, Proceedings of RuPAC 2006, Nowosibirsk, Russland , ist es bekannt, zwischen der Vakuumkammer und dem Magneten einen Vakuumspalt zu lassen. Die Vakuumkammer kann sich zwar erwärmen, die Wärme wird wegen des Spalts aber nicht auf den Magneten übertragen, da der Magnet und die Vakuumkammer gesondert gekühlt werden. Nachteilig hieran ist, dass diese Anordnung zu einer Verkleinerung des freien Raumes, der dem Teilchenstrahl zur Verfügung steht, führt.Out S. Khrushchev, V. Lev, N. Mezensev, E. Miginsky, V. Repkov, V. Shkaruba, V. Syrovatin, V. Tsukanov, 3.5 Tesla 49-pole superconducting wiggler for DLS, Proceedings of RuPAC 2006, Novosibirsk, Russia , It is known to leave a vacuum gap between the vacuum chamber and the magnet. Although the vacuum chamber can heat up, the heat is not transmitted to the magnet because of the gap, since the magnet and the vacuum chamber are cooled separately. The disadvantage of this is that this arrangement leads to a reduction of the free space available to the particle beam.

Aus C.S.Hwang et al, "Comparison of Predesign Parameters for Mini-Pole In-Vacuo Superconducting Undulators", IEEE Transactions on Applied Superconductivity, Vol.14, No.2, June 2004, Seiten 580-584 , ist ein Undulator bekannt, der eine Schicht aus Kupfer und Nickel umfasst, die Erwärmung der supraleitenden Magneten zu verringern.Out CSHwang et al, "Comparison of Predesign Parameters for Mini-Pole In-Vacuo Superconducting Undulators", IEEE Transactions on Applied Superconductivity, Vol. 14, No.2, June 2004, pages 580-584 , an undulator is known which comprises a layer of copper and nickel to reduce the heating of the superconducting magnets.

Aus der DE 27 31 458 A1 ist eine Vorrichtung bekannt, die zur Aufnahme eines Teilchenstrahls (Elektronenstrahls) vorgesehen ist, wobei sich zwischen dem Teilchenstrahl und einem supraleitenden Magneten (Linsenspulenwicklung) eine topfartig ausgebildete Abschirmvorrichtung aus supraleitendem Material befindet.From the DE 27 31 458 A1 a device is known, which is provided for receiving a particle beam (electron beam), wherein between the particle beam and a superconducting magnet (lens coil winding) is a cup-shaped shielding device made of superconducting material.

Die US 3,290,219 A , die WO 2007/122025 A1 und die DE 10 2006 027 218 A1 offenbaren weitere Vorrichtungen zur Aufnahme von geladenen Teilchenstrahlen, die von mehreren supraleitenden Magneten umgeben sind bzw. bei denen ein supraleitendes Material in eine normalleitende Spule eingebaut wird, um die Erwärmung der Spule zu verhindern, die bei der Erzeugung von Spiegelladungen entsteht.The US 3,290,219 A , the WO 2007/122025 A1 and the DE 10 2006 027 218 A1 disclose other devices for receiving charged particle beams, which are surrounded by a plurality of superconducting magnets or in which a superconducting material is incorporated in a normal conducting coil to prevent the heating of the coil, which results in the production of mirror charges.

Daher besteht die Aufgabe der vorliegenden Erfindung darin, eine Vorrichtung zur Verringerung der Erwärmung einer Vakuumkammer, die zur Aufnahme eines geladenen Teilchenstrahls in einem Beschleuniger vorgesehen ist, sowie eine Vakuumkammer,Therefore, the object of the present invention is to provide a device for reducing the heating of a vacuum chamber, which is provided for receiving a charged particle beam in an accelerator, and a vacuum chamber,

die mit einer derartigen Vorrichtung ausgestattet ist, vorzuschlagen, die die genannten Nachteile und Einschränkungen nicht aufweisen. which is equipped with such a device to propose that do not have the disadvantages and limitations mentioned.

Insbesondere soll eine derartige Vorrichtung bereitgestellt werden, die es ermöglicht, dass das von einem supraleitenden Magneten ausgehende Magnetfeld möglichst ungehindert auf den geladenen Teilchenstrahl, der die Vakuumkammer durchläuft, auftrifft.In particular, such a device is to be provided which makes it possible for the magnetic field emanating from a superconducting magnet to strike the charged particle beam passing through the vacuum chamber as unhindered as possible.

Diese Aufgabe wird im Hinblick auf die Vorrichtung durch die Merkmale des Anspruchs 1 und im Hinblick auf die Vakuumkammer durch die Merkmale des Anspruchs 10 gelöst. Die Unteransprüche beschreiben vorteilhafte Ausgestaltungen der Erfindung.This object is achieved with regard to the device by the features of claim 1 and with respect to the vacuum chamber by the features of claim 10. The subclaims describe advantageous embodiments of the invention.

Die erfindungsgemäße Vorrichtung weist eine Vielzahl von supraleitenden Streifen auf, die zwischen dem geladenen Teilchenstrahl und dem supraleitenden Magneten angeordnet sind.The device according to the invention has a multiplicity of superconducting strips which are arranged between the charged particle beam and the superconducting magnet.

In einer bevorzugten Ausgestaltung sind die supraleitenden Streifen jeweils parallel zueinander in mindestens einer Reihe angeordnet. Vorzugsweise sind die Streifen hierbei parallel zur Strahlrichtung des Teilchenstrahls angeordnet.In a preferred embodiment, the superconducting strips are each arranged parallel to one another in at least one row. Preferably, the strips are arranged parallel to the beam direction of the particle beam.

Sind die Streifen innerhalb einer Reihe in einem Abstand voneinander, der ihrer Breite entspricht, angeordnet, so wird dadurch die Erwärmung der Vakuumkammer durch die Spiegelströme halbiert, da sich die Hälfte der Spiegelströme in einem supraleitenden Material mit dem Widerstand Null bewegt und daher nicht zur Ohmschen Erwärmung beiträgt.If the strips are arranged within a row at a distance from each other that corresponds to their width, this halves the heating of the vacuum chamber by the mirror currents, since half of the mirror currents in a zero-resistance superconducting material move and therefore not to ohmic Warming contributes.

In einer besonders bevorzugten Ausgestaltung sind die supraleitenden Streifen auf mindestens zwei gesonderte Reihen, die räumlich gegeneinander versetzt sind, verteilt. Hierbei sind die supraleitenden Streifen in den mindestens zwei Reihen derart gegeneinander versetzt, dass diese, vom Teilchenstrahl aus betrachtet, eine möglichst große Fläche überdecken.In a particularly preferred embodiment, the superconducting strips are distributed over at least two separate rows, which are spatially offset from one another. Here, the superconducting strips in the at least two rows are such offset from one another, that these, viewed from the particle beam, cover the largest possible area.

Insgesamt ist die Vielzahl der supraleitenden Streifen derart angeordnet, dass der geladene Teilchenstrahl eine möglichst homogene und möglichst geschlossene supraleitende Oberfläche "sieht", das Magnetfeld aber möglichst ungehindert durch die Vielzahl der supraleitenden Streifen hindurchgeht.Overall, the plurality of superconducting strips is arranged in such a way that the charged particle beam "sees" a superconducting surface that is as homogeneous and as closed as possible, but that the magnetic field passes through the plurality of superconducting strips as unhindered as possible.

Die Dicke der supraleitenden Streifen nimmt vorzugsweise einen Wert im Bereich von 100 nm bis 1 µm an.The thickness of the superconducting strips preferably assumes a value in the range of 100 nm to 1 μm.

In einer besonderen Ausgestaltung ist die Vielzahl von supraleitenden Streifen auf einem Träger aufgebracht, der zwischen dem geladenen Teilchenstrahl und dem supraleitenden Magneten angeordnet ist. Der Träger besteht aus einem festen, metallischen oder vorzugsweise isolierenden Material. Die Dicke des Trägers beträgt vorzugsweise 10 µm bis 1000 µm.In a particular embodiment, the plurality of superconductive strips are deposited on a support disposed between the charged particle beam and the superconducting magnet. The carrier consists of a solid, metallic or preferably insulating material. The thickness of the support is preferably 10 μm to 1000 μm.

In einer besonders bevorzugten Ausgestaltung werden auf die beiden Seiten des Trägers jeweils supraleitende Streifen derart aufgebracht, dass die Streifen auf der einen Seite in Bezug zu den Streifen auf der anderen Seite versetzt aufgebracht sind.In a particularly preferred embodiment, superconducting strips are respectively applied to the two sides of the carrier in such a way that the strips are applied offset on one side in relation to the strips on the other side.

Die Erfindung betrifft weiterhin eine Vakuumkammer, insbesondere in einem Beschleuniger, zur Aufnahme eines geladenen Teilchenstrahls, auf den ein von einem supraleitenden Magneten ausgehendes Magnetfeld auftrifft, die mit einer erfindungsgemäßen Vorrichtung ausgestattet ist.The invention further relates to a vacuum chamber, in particular in an accelerator, for receiving a charged particle beam, on which a magnetic field emanating from a superconducting magnet impinges, which is equipped with a device according to the invention.

Der mit der erfindungsgemäßen Vorrichtung erzielte physikalische Effekt lässt sich wie folgt erklären:

  • Die in der Vakuumkammer induzierten Ströme erwärmen die Vakuumkammer und den Magneten wegen des endlichen Ohmschen Widerstands der Vakuumkammer. Aufgrund des so genannten Skin-Effekts bewegen sich die Ströme im Allgemeinen in einer dünnen Schicht an der dem Strahl zugewandten Seite der kalten Vakuumkammer. Der hierdurch erzeugte Widerstand und die damit verbundene Erwärmung würden unterbleiben, wenn die Vakuumkammer aus supraleitendem Material mit dem Ohmschen Widerstand Null bestünde.
The physical effect achieved with the device according to the invention can be explained as follows:
  • The currents induced in the vacuum chamber heat the vacuum chamber and the magnet because of the finite ohmic resistance of the vacuum chamber. Due to the so-called skin effect , the streams generally move in a thin layer on the jet-facing side of the cold vacuum chamber. The resistance produced thereby and the associated heating would be omitted if the vacuum chamber made of superconducting material with the ohmic resistance zero.

Da ein Supraleiter jedoch ein Diamagnet ist, werden die magnetischen Feldlinien bei einem so genannten Typ I Supraleiter vollständig bzw. bei einem so genannten Typ II Supraleiter teilweise verdrängt, so dass eine supraleitende Vakuumkammer zwar die Erwärmung durch die Spiegelströme verhindert, gleichzeitig aber das für die Beaufschlagung des geladenen Teilchenstrahls erforderliche Magnetfeld verringern oder auslöschen würde. Eine derartige Reduktion der Feldstärke durch eine dünne supraleitende Schicht eines Typ II Supraleiters konnte experimentell nachgewiesen werden.However, since a superconductor is a diamagnet, the magnetic field lines in a so-called type I superconductor are completely displaced or in a so-called type II superconductor partially displaced, so that a superconducting vacuum chamber prevents heating by the mirror currents, but at the same time for the Reduce or eliminate the magnetic field required by the charged particle beam. Such a reduction of the field strength by a thin superconducting layer of a type II superconductor could be detected experimentally.

Erfindungsgemäß wird die Verringerung des Magnetfelds dadurch verhindert, dass die dem Teilchenstrahl zugewandte Seite zwar aus einer supraleitenden Schicht besteht, diese Schicht jedoch streifenförmig unterbrochen ist. Die Feldlinien werden gemäß dem diamagnetischen Verhalten des Supraleiters jeweils um die supraleitenden Streifen abgelenkt und auf diese Weise nur sehr geringfügig abgeschwächt.According to the invention, the reduction of the magnetic field is prevented by the fact that the side facing the particle beam is indeed composed of a superconducting layer, but this layer is interrupted in strip form. The field lines are deflected according to the diamagnetic behavior of the superconductor in each case to the superconducting strips and attenuated in this way only very slightly.

Die erfindungsgemäße Vorrichtung ermöglicht die Verringerung der Erwärmung einer Vakuumkammer durch die weitgehende Vermeidung der Ausbildung von Spiegelströmen in der Wand der Vakuumkammer bzw. der Oberfläche des Magneten, wobei das Magnetfeld jedoch weitgehend ungehindert durch die Vielzahl der supraleitenden Streifen hindurchgeht, und eignet sich daher für die Verwendung in Vakuumkammern, vor allem in Beschleunigern.The device of the invention makes it possible to reduce the heating of a vacuum chamber by largely avoiding the formation of mirror currents in the wall of the vacuum chamber or the surface of the magnet, wherein the magnetic field passes through the plurality of superconducting strips largely unhindered, and is therefore suitable for the Use in vacuum chambers, especially in accelerators.

Die Erfindung wird im Folgenden anhand eines Ausführungsbeispiels und der Figuren näher erläutert. Hierbei zeigen:

Fig. 1
Vorrichtung mit in einer Reihe angeordneten supraleitenden Streifen in einer Vakuumkammer.
Fig. 2
Vorrichtung mit in einer Reihe angeordneten supraleitenden Streifen auf einem Träger in einer Vakuumkammer.
Fig. 3
Vorrichtung mit in zwei gesonderten Reihen angeordneten supraleitenden Streifen in einer Vakuumkammer.
Fig. 4
Vorrichtung mit in zwei gesonderten Reihen angeordneten supraleitenden Streifen auf einem Träger in einer Vakuumkammer.
The invention will be explained in more detail below with reference to an embodiment and the figures. Hereby show:
Fig. 1
Device having in-line superconducting strips in a vacuum chamber.
Fig. 2
Device having in-line superconducting strips on a support in a vacuum chamber.
Fig. 3
Device with superconducting strips arranged in two separate rows in a vacuum chamber.
Fig. 4
Device with two separate rows arranged superconducting strips on a support in a vacuum chamber.

Fig. 1 zeigt eine erfindungsgemäße Vorrichtung, die in Form von in einer Reihe angeordneten supraleitenden Streifen 3, 3' in einer Vakuumkammer ausgeführt ist. Dadurch wird die Erwärmung des supraleitenden Magneten 2 durch die vom Teilchenstrahl 1 induzierten Spiegelströme verringert, da sich ein Teil der Spiegelströme in einem supraleitenden Material mit dem Widerstand Null bewegt und daher nicht zur Erwärmung beiträgt. Die Feldlinien 5 des Supraleiters werden entsprechend seinem diamagnetischen Verhalten jeweils um die supraleitenden Streifen 3, 3' abgelenkt und auf diese Weise nur sehr geringfügig in der Größenordnung von 1 % abgeschwächt. Fig. 1 shows a device according to the invention, which is designed in the form of arranged in a row superconducting strips 3, 3 ' in a vacuum chamber. Thereby, the heating of the superconducting magnet 2 is reduced by the induced by the particle beam 1 mirror currents, since a part of the mirror currents in a superconducting material moves with the resistance zero and therefore does not contribute to the heating. The field lines 5 of the superconductor are deflected according to its diamagnetic behavior in each case to the superconducting strips 3, 3 ' and attenuated in this way only very slightly on the order of 1%.

In Fig. 2 ist eine erfindungsgemäße Vorrichtung, die wie in Fig. 1 in einer Vakuumkammer in Form von in einer Reihe angeordneten supraleitenden Streifen 3, 3' auf einem isolierenden Träger 6 ausgeführt ist, dargestellt.In Fig. 2 is a device according to the invention, as in Fig. 1 in a vacuum chamber in the form of arranged in a row superconducting strips 3, 3 ' on an insulating support 6 is shown.

Fig. 3 zeigt eine erfindungsgemäße Vorrichtung, die in einer Vakuumkammer in Form von in zwei gesonderten Reihen angeordneten supraleitenden Streifen 3, 3' bzw. 4, 4', 4" ausgeführt ist. Fig. 3 shows an inventive device, which is in a vacuum chamber in the form of arranged in two separate rows superconducting strips 3, 3 ' and 4, 4', 4 "is executed.

In Fig. 4 ist eine erfindungsgemäße Vorrichtung, die wie in Fig. 3 in einer Vakuumkammer in Form von in zwei gesonderten Reihen angeordneten supraleitenden Streifen 3, 3' bzw. 4, 4', 4", die sich jeweils auf gegenüber liegenden Seite des isolierenden Trägers 6 befinden, ausgeführt ist, dargestellt.In Fig. 4 is a device according to the invention, as in Fig. 3 in a vacuum chamber in the form of arranged in two separate rows superconducting strips 3, 3 ' and 4, 4' , 4 ", which are located respectively on opposite side of the insulating support 6 , is shown.

Claims (10)

  1. Device for reducing the heating of a vacuum chamber, which is provided to accommodate a charged particle beam (1), wherein a magnetic field emitted by a superconductive magnet (2) impinges on the particle beam (1), characterised by a plurality of superconductive strips (3, 3', ... ) which are arranged between the charged particle beam (1) and the superconductive magnet (2).
  2. Device according to claim 1, wherein the superconductive strips (3, 3', ...) are in each case arranged parallel to one another in at least one row.
  3. Device according to claim 1 or 2, wherein the strips are arranged within a row at a distance from one another which corresponds to their width.
  4. Device according to any one of claims 1 to 3, wherein the superconductive strips (3, 3', ... ) are arranged in each case parallel to the beam direction of the particle beam (1).
  5. Device according to any one of claims 1 to 4, wherein the thickness of the superconductive strips (3, 3', ...) amounts to 100 nm to 1 µm.
  6. Device according to any one of claims 1 to 5, wherein the plurality of superconducting strips (3, 3', ... ) are located on a carrier (6), which is arranged between the charged particle beam (1) and the superconductive magnet (2).
  7. Device according to any one of claims 1 to 6, wherein at least two separate rows of superconductive strips (3, 3', ..; 4, 4', ...) are provided, which are spatially offset in relation to one another.
  8. Device according to claim 7, wherein two separate rows of superconductive strips (3, 3', ..; 4, 4', ...) are provided, which in each case are located on one side of the carrier (6), spatially offset in relation to the strips on the respective other side of the carrier (6).
  9. Device according to any one of claims 6 to 8, wherein the thickness of the carrier (6) is from 10 µm to 1000 µm.
  10. Vacuum chamber, which is provided to accommodate a charged particle beam (1) onto which a magnetic field impinges, emitted by a superconductive magnet (2), comprising a device according to one of claims 1 to 9.
EP11001598.9A 2010-03-19 2011-02-26 Device for reducing the heating of a vacuum chamber Not-in-force EP2367404B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE102010012073A DE102010012073B4 (en) 2010-03-19 2010-03-19 Device for reducing the heating of a vacuum chamber

Publications (3)

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EP2367404A2 EP2367404A2 (en) 2011-09-21
EP2367404A3 EP2367404A3 (en) 2014-02-26
EP2367404B1 true EP2367404B1 (en) 2015-11-25

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Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3290219A (en) * 1963-09-19 1966-12-06 Gen Electric Plasma containment method and apparatus
DE2731458C3 (en) * 1977-07-12 1980-03-20 Siemens Ag, 1000 Berlin Und 8000 Muenchen Magnetic objective lens device for corpuscular beam devices operating under vacuum, in particular objective lens device for high-voltage electron microscopes and use
DE102006018635B4 (en) * 2006-04-21 2008-01-24 Siemens Ag Irradiation system with a gantry system with a curved beam guiding magnet
DE102006027218A1 (en) * 2006-06-12 2007-12-20 Siemens Ag Magnet for the guidance of a beam of electrically charged particles along a path of the particles, comprises an evacuable beam guidance tube that encloses the path of the particles, and a winding chamber that encloses the guidance tube

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EP2367404A3 (en) 2014-02-26
EP2367404A2 (en) 2011-09-21
DE102010012073B4 (en) 2012-05-31
DE102010012073A1 (en) 2011-09-22

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