2825results about "Stability-of-path spectrometers" patented technology

A synchrocyclotron comprises a resonant circuit that includes electrodes having a gap therebetween across the magnetic field. An oscillating voltage input, having a variable amplitude and frequency determined by a programmable digital waveform generator generates an oscillating electric field across the gap. The synchrocyclotron can include a variable capacitor in circuit with the electrodes to vary the resonant frequency. The synchrocyclotron can further include an injection electrode and an extraction electrode having voltages controlled by the programmable digital waveform generator. The synchrocyclotron can further include a beam monitor. The synchrocyclotron can detect resonant conditions in the resonant circuit by measuring the voltage and or current in the resonant circuit, driven by the input voltage, and adjust the capacitance of the variable capacitor or the frequency of the input voltage to maintain the resonant conditions. The programmable waveform generator can adjust at least one of the oscillating voltage input, the voltage on the injection electrode and the voltage on the extraction electrode according to beam intensity and in response to changes in resonant conditions.

The invention concerns a device (10) for regulating the intensity of a beam extracted from a particle accelerator, such as a cyclotron, used for example for protontherapy, said particles being generated from an ion source. The invention is characterized in that it comprises at least: a comparator (90) determining a difference ε between a digital signal IR representing the intensity of the beam measured at the output of the accelerator and a setpoint value IC of the beam intensity: a Smith predictor (80) which determines on the basis of the difference ε, a correct value of the intensity of the beam IP; an inverted correspondence table (40) supplying, on the basis of the corrected value of the intensity of the beam IP, a setpoint value IA for supply arc current from the ion source (20).

A mass spectrometer is disclosed wherein ions having a particular desired charge state are selected by operating an ion mobility spectrometer in combination with a quadrupole mass filter. Precursor ions are fragmented or reacted to form product ions in a collision cell ion trap and sent back upstream to an upstream ion trap. The fragment or product ions are then passed through the ion mobility spectrometer wherein they become temporally separated according to their ion mobility. Fragment or product ions are then re-trapped in the collision cell ion trap before being released therefrom in packets. A pusher electrode of a time of flight mass analyzer is energized a predetermined period of time after a packet of ions is released from the collision cell ion trap. Accordingly, it is possible to select multiply charged precursor ions from a background of singly charged ions, fragment them, and mass analyze the fragment ions with a near 100% duty cycle across the whole mass range.

This invention relates to tandem mass spectrometry and, in particular, to tandem mass spectrometry using a linear ion trap and a time of flight detector to collect mass spectra to form a MS / MS experiment. The accepted standard is to store and mass analyze precursor ions in the ion trap before ejecting the ions axially to a collision cell for fragmentation before mass analysis of the fragments in the time of flight detector. This invention makes use of orthogonal ejection of ions with a narrow range of m / z values to produce a ribbon beam of ions that are injected into the collision cell. The shape of this beam and the high energy of the ions are accommodated by using a planar design of collision cell. Ions are retained in the ion trap during ejection so that successive narrow ranges may be stepped through consecutively to cover all precursor ions of interest.

A new geometry ion trap and its use as a mass spectrometer is described. The ion traps can be combined linearly and in parallel to form systems for mass storage, analysis, fragmentation, separation, etc. of ions. The ion trap has a simple rectilinear geometry with a high trapping capacity. It can be operated to provide mass analysis in the mass-selective instability mode as well as the mass-selective stability mode. Arrays of multiple ion traps allow combinations of multiple gas-phase processes to be applied to the trapped ions to achieve high sensitivity, high selectivity and / or higher throughput in the analysis of ions.

A three section linear or two-dimensional (2D) quadrupole ion trap as a high performance mass spectrometer is described. Mass analysis is performed by ejecting ions radically out a slot formed in one of the rods using the mass selective instability mode of operation. The slot geometry is optimized to yield high ejection efficiencies. Resolution can be controlled by using appropriate end section potentials to control the axial spread of the ion cloud. Multiple detectors can be used for enhancing sensitivity and for enabling enhanced ion analysis techniques in the ion trap.

An objective lens with magnetic and electrostatic focusing for an electron microscopy system is provided whose at least partially conical outer shape allows orienting an object to be imaged at a large angle range in respect of an electron beam, said objective lens exhibiting, at the same time, good optical parameters. This is enabled by a specific geometry of the lens elements. Furthermore, an examination for the simultaneous imaging and processing of an object is proposed which comprises, besides an electron microscopy system with the above-mentioned objective lens, also an ion beam processing system and an object support.

A power supply for applying a voltage to a scanning electromagnet for deflecting a charged particle beam has a first power supply unit having no filter and a second power supply unit having a filter. When an irradiation position of the charged particle beam in an irradiation object is moved, the first power supply unit, namely a power supply unit having no filter, is used to apply the voltage to the scanning electromagnet, so that an exciting current flowing in the scanning electromagnet can be changed in a short time. Further, when the irradiation position of the charged particle beam is maintained, the second power supply is used to apply a voltage whose pulsating component was removed to the scanning electromagnet, so that the exciting current flowing in the scanning electromagnet can be controlled precisely. Consequently, the charged particle beam can be applied uniformly to the irradiation object and an irradiation time of the charged particle beam to the irradiation object can be curtailed.

The invention comprises an ion beam focusing method and apparatus used as part of an ion beam injection system, which is used in conjunction with multi-axis charged particle or proton beam radiation therapy of cancerous tumors. The ion beam focusing system includes two or more electrodes where one electrode of each electrode pair partially obstructs the ion beam path with conductive paths, such as a conductive mesh. In a given electrode pair, electric field lines, running between the conductive mesh of a first electrode and a second electrode, provide inward forces focusing the negative ion beam. Multiple such electrode pairs provide multiple negative ion beam focusing regions.

A method for slowing and controlling a beam of charged particles includes the steps of superimposing at least one magnetic field on a mass and passing the beam through the mass and at least one magnetic field such that the beam and the mass slows but does not stop the particles. An apparatus for slowing and controlling a beam of charged particles includes a bending magnetic field superimposed on a focusing magnetic field within a mass.