Abstract: A column-sealing tool is provided for use during decoupling of a capillary column from a gas chromatography-mass spectrometry (GC-MS) system. The column-sealing tool includes an engagement structure for removably securing the column-sealing tool within a high vacuum enclosure of the GC-MS system, at a location between a high vacuum end of a transfer line and a mass analyzer of the GC-MS system. Additionally, the column-sealing tool includes a sealing element that is actuatable between a non-sealing position and a sealing position. During use the sealing element forms a secondary vacuum seal with the first end of the transfer line when the column-sealing tool is inserted into the GC-MS system and when the sealing element is in the sealing position.

Abstract: A method of operating a mass spectrometer comprising: detecting a first ion species using a first gain setting of a detector or a first emission current for a first mass-to-charge range; detecting a second ion species using a second gain setting of the detector or a second emission current for a second mass-to-charge range; and using the detected first and second ion species to calibrate the mass range of a mass analyzer of the mass spectrometer, to tune the resolution of the mass analyzer, or to tune an ion optic of the mass spectrometer.

Abstract: A column-sealing tool is provided for use during decoupling of a capillary column from a gas chromatography-mass spectrometry (GC-MS) system. The column-sealing tool includes an engagement structure for removably securing the column-sealing tool within a high vacuum enclosure of the GC-MS system, at a location between a high vacuum end of a transfer line and a mass analyzer of the GC-MS system. Additionally, the column-sealing tool includes a sealing element that is actuatable between a non-sealing position and a sealing position. During use the sealing element forms a secondary vacuum seal with the first end of the transfer line when the column-sealing tool is inserted into the GC-MS system and when the sealing element is in the sealing position.

Abstract: A column-sealing tool is provided for use during decoupling of a capillary column from a gas chromatography-mass spectrometry (CG-MS) system. The column-sealing tool includes an engagement structure for removably securing the column-sealing tool within a high vacuum enclosure of the GC-MS system, at a location between a high vacuum end of a transfer line and a mass analyzer of the GC-MS system. Additionally, the column-sealing tool includes a sealing element that is actuatable between a non-sealing position and a sealing position. During use the sealing element forms a secondary vacuum seal with the first end of the transfer line when the column-sealing tool is inserted into the GC-MS system and when the sealing element is in the sealing position.

Abstract: A method includes producing ions from one or more calibrant species and delivering the ions to a mass analyzer, and measuring a first set of mass related physical values for the ions from the one or more calibrant species. The method further includes producing ions from a sample and delivering the ions to a mass analyzer, and measuring a second mass related physical value for a first sample ion species. The first sample ion species has a mass-to-charge ratio outside of the range of the mass-to-charge ratios of the calibrant ion species. Additionally, the method includes calculating a calibration curve based on the first set of mass related physical values and second mass related physical value, and modifying at least one instrument parameter based on the calibration curve.

Abstract: A column-sealing tool is provided for use during decoupling of a capillary column from a gas chromatography-mass spectrometry (CG-MS) system. The column-sealing tool includes an engagement structure for removably securing the column-sealing tool within a high vacuum enclosure of the GC-MS system, at a location between a high vacuum end of a transfer line and a mass analyzer of the GC-MS system. Additionally, the column-sealing tool includes a sealing element that is actuatable between a non-sealing position and a sealing position. During use the sealing element forms a secondary vacuum seal with the first end of the transfer line when the column-sealing tool is inserted into the GC-MS system and when the sealing element is in the sealing position.

Abstract: An electron source can selectively provide a first stream of electrons that travels in a direction along an imaginary line to a location remote from the electron source, or a second stream of electrons that travels in the direction along the line to the location. The electron source includes a first electron emitter for selectively emitting electrons for the first stream, and a second electron emitter for selectively emitting electrons for the second stream. A different aspect relates to a method for operating an apparatus having an electron source that includes first and second electron emitters. The method includes selectively producing a first stream of electrons that travels from the first electron emitter in a direction along an imaginary line to a location remote from the electron source, or a second stream of electrons that travels from the second electron emitter in the direction along the line to the location.

Abstract: A method and apparatus of combining an ion volume, a lens stack, and an ion optic that similarly cooperates with a detached multipole ion guide is herein incorporated into a single sub-assembly that can be removed from a mass spectrometer instrument without venting. Such an arrangement allows an operator to clean all parts of the ion path that get contaminated in normal operation, reassemble and reinsert in a timely manner and then pump down to an acceptable vacuum without having to vent the system.

Abstract: A method includes: accumulating ions having a plurality of m/z values in an ion trap during a time interval; deriving from the accumulated ions a respective intensity value for each of the m/z values; and adjusting each of the intensity values as a function of the time needed by the ion trap to begin collecting ions with the corresponding m/z value. According to a different aspect, an apparatus includes a first portion with an ion trap, and a second portion. The second portion causes the ion trap to accumulate ions with a plurality of m/z values during a time interval, derives from the accumulated ions in the ion trap a respective intensity value for each of the m/z values, and adjusts each of the intensity values as a function of the time needed by the ion trap to begin collecting ions with the corresponding m/z value.

Abstract: A method for operating a mass spectrometer includes determining a first performance characteristic while operating the mass spectrometer with a first electron emitter, storing first information relating to the first performance characteristic, determining a second performance characteristic while operating the mass spectrometer with a second electron emitter, storing second information relating to the second performance characteristic, and thereafter switching from operation using the first electron emitter to operation using the second electron emitter. The switching includes using the first and second information to normalize performance of the second electron emitter after the switching relative to performance of the first electron emitter before the switching.

Abstract: A method and apparatus of combining an ion volume, a lens stack, and an ion optic that similarly cooperates with a detached multipole ion guide is herein incorporated into a single sub-assembly that can be removed from a mass spectrometer instrument without venting. Such an arrangement allows an operator to clean all parts of the ion path that get contaminated in normal operation, reassemble and reinsert in a timely manner and then pump down to an acceptable vacuum without having to vent the system.

Abstract: A method for operating a mass spectrometer includes determining a first performance characteristic while operating the mass spectrometer with a first electron emitter, storing first information relating to the first performance characteristic, determining a second performance characteristic while operating the mass spectrometer with a second electron emitter, storing second information relating to the second performance characteristic, and thereafter switching from operation using the first electron emitter to operation using the second electron emitter. The switching includes using the first and second information to normalize performance of the second electron emitter after the switching relative to performance of the first electron emitter before the switching.

Abstract: A variable duty cycle ion source assembly is coupled to a continuous beam mass spectrometer. The duty cycle can be adjusted based on previous scan data or real time sampling of ion intensities during mass analysis. This provides the ability to control the total number of ions formed, mass analyzed and detected for each ion mass of interest. The frequency of the ion source can be sufficiently high (kHz range) so as to maintain accurate peak centroiding. The ion source assembly can be used for both electron ionization (EI) or chemical ionization (CI) modes of operation.

Abstract: An electron source can selectively provide a first stream of electrons that travels in a direction along an imaginary line to a location remote from the electron source, or a second stream of electrons that travels in the direction along the line to the location. The electron source includes a first electron emitter for selectively emitting electrons for the first stream, and a second electron emitter for selectively emitting electrons for the second stream. A different aspect relates to a method for operating an apparatus having an electron source that includes first and second electron emitters. The method includes selectively producing a first stream of electrons that travels from the first electron emitter in a direction along an imaginary line to a location remote from the electron source, or a second stream of electrons that travels from the second electron emitter in the direction along the line to the location.

Abstract: An apparatus and method are disclosed for efficient detection of ions ejected from a quadrupolar ion trap, in which the ions are ejected as first and second groups of ions having different directions. The first and second groups of ions are received by a conversion dynode structure, which responsively emits secondary particles that are directed to a shared detector, such as an electron multiplier. The conversion dynode structure may be implemented as a common dynode or as two dynodes (or sets of dynodes), with each dynode positioned to receive one of the groups of ions.

Abstract: A method includes: accumulating ions having a plurality of m/z values in an ion trap during a time interval; deriving from the accumulated ions a respective intensity value for each of the m/z values; and adjusting each of the intensity values as a function of the time needed by the ion trap to begin collecting ions with the corresponding m/z value. According to a different aspect, an apparatus includes a first portion with an ion trap, and a second portion. The second portion causes the ion trap to accumulate ions with a plurality of m/z values during a time interval, derives from the accumulated ions in the ion trap a respective intensity value for each of the m/z values, and adjusts each of the intensity values as a function of the time needed by the ion trap to begin collecting ions with the corresponding m/z value.

Abstract: An apparatus and method are disclosed for efficient detection of ions ejected from a quadrupolar ion trap, in which the ions are ejected as first and second groups of ions having different directions. The first and second groups of ions are received by a conversion dynode structure, which responsively emits secondary particles that are directed to a shared detector, such as an electron multiplier. The conversion dynode structure may be implemented as a common dynode or as two dynodes (or sets of dynodes), with each dynode positioned to receive one of the groups of ions.

Abstract: A variable duty cycle ion source assembly is coupled to a continuous beam mass spectrometer. The duty cycle can be adjusted based on previous scan data or real time sampling of ion intensities during mass analysis. This provides the ability to control the total number of ions formed, mass analyzed and detected for each ion mass of interest. The frequency of the ion source can be sufficiently high (kHz range) so as to maintain accurate peak centroiding. The ion source assembly can be used for both electron ionization (EI) or chemical ionization (CI) modes of operation.

Abstract: An apparatus for delivering calibrant gas at selected flow rates to the ionization region of a mass spectrometer which employs capillary flow restrictors for metering the flow.

Abstract: An apparatus for delivering calibrant gas at selected flow rates to the ionization region of a mass spectrometer which employs capillary flow restrictors for metering the flow.