Abstract: A first searcher executes a primary search with respect to a primary library based on a sample mass spectrum. The primary library includes a plurality of standard mass spectra. When a judging unit judges that a search range is to be enlarged, a second searcher executes a secondary search with respect to a secondary library based on the sample mass spectrum. The secondary library includes a plurality of predicted mass spectra produced from a plurality of molecular structures.

Abstract: An evaluation section identifies, in a list of candidate compounds, a group of candidate compounds having the degree of reverse similarity greater than or equal to a threshold s1. When all candidates in the group of candidate compounds have differences between the degrees of similarity that are greater than or equal to a threshold s2, the evaluation section judges that there is a composite state. The difference between the degrees of similarity is computed by subtracting the degree of forward similarity from the degree of reverse similarity. The similarity ratio may be used in place of the difference between the degrees of similarity.

Abstract: A partial structure estimation apparatus is configured to generate a first explanatory variable by performing composition estimation for each peak in a mass spectrum acquired from a sample, and to generate a second explanatory variable by performing composition estimation for each peak interval in the mass spectrum. The partial structure estimation apparatus is further configured to then estimate a partial structure as an objective variable based on the first explanatory variable and the second explanatory variable. In a partial structure estimation model generation apparatus, a partial structure estimation model is generated through machine learning using a training data set.

Abstract: Each estimated composition candidate is evaluated based on a mass spectrum produced using soft ionization and a mass spectrum produced using hard ionization. In the evaluation, a comparison between two measured isotope patterns (primary pattern matching), and a comparison between the measured isotope pattern and a theoretical isotope pattern (secondary pattern matching) are applied stepwise.

Abstract: A composition of a focused portion corresponding to a portion of a molecular ion is estimated as a partial composition based on a mass of the focused portion. An initial composition search range is modified based on the partial composition. A composition of the molecular ion is estimated as an overall composition based on a mass of the molecular ion under a modified composition search range. A way of modifying the composition search range may include a method for modifying a lower limit to a range of the number of atoms and a method for adding a new range of the number of atoms associated with a new chemical element.

Abstract: A composition estimation target peak is selected from a mass spectrum of a sample, and a group of measured isotope peaks related to the composition estimation target peak is selected. A composition candidate for the sample is estimated based on the composition estimation target peak. A distribution of a theoretical isotope peak corresponding to the composition candidate is calculated. Presence or absence of an adduct ion or a desorbed ion in the sample is determined based on a first mass difference between isotopes in a distribution of the measured isotope peaks and a second mass difference between isotopes in the distribution of the theoretical isotope peak.

Abstract: A first mass spectrum including a fragment ion peak is generated under application of a first ionization method. A second mass spectrum including a molecular ion peak is generated under application of a second ionization method. These mass spectra are synthesized to generate a synthesized mass spectrum. On the synthesized mass spectrum, difference information, such as a mass difference and difference composition, is calculated between the molecular ion peak and the fragment ion peak.

Abstract: In a mass spectrometry apparatus, an electric field is applied to an injected specimen to ionize the specimen, and mass spectrometry of the specimen is performed. In an emitter which ionizes the specimen, a flashing process to increase a temperature of the emitter is repeatedly performed at a short-time interval during an injection period of the specimen. A flashing current controller controls a flashing current value to be applied to the emitter to increase, in a long term, a flashing temperature which the emitter reaches in the flashing process.

Abstract: Mass spectrometry for a specimen is repeatedly performed while stepwise changing a parameter (for example, a current value) of an emitter current. Based on a plurality of chromatograms generated by this process, an evaluation value table including a plurality of evaluation values is generated. An individual evaluation value shows a degree of tailing for individual peak included in each chromatogram. A parameter function is generated based on the evaluation value table. The parameter of the emitter current is controlled according to the parameter function.

Abstract: An evaluation section identifies, in a list of candidate compounds, a group of candidate compounds having the degree of reverse similarity greater than or equal to a threshold s1. When all candidates in the group of candidate compounds have differences between the degrees of similarity that are greater than or equal to a threshold s2, the evaluation section judges that there is a composite state. The difference between the degrees of similarity is computed by subtracting the degree of forward similarity from the degree of reverse similarity. The similarity ratio may be used in place of the difference between the degrees of similarity.

Abstract: Each estimated composition candidate is evaluated based on a mass spectrum produced using soft ionization and a mass spectrum produced using hard ionization. In the evaluation, a comparison between two measured isotope patterns (primary pattern matching), and a comparison between the measured isotope pattern and a theoretical isotope pattern (secondary pattern matching) are applied stepwise.

Abstract: A composition of a focused portion corresponding to a portion of a molecular ion is estimated as a partial composition based on a mass of the focused portion. An initial composition search range is modified based on the partial composition. A composition of the molecular ion is estimated as an overall composition based on a mass of the molecular ion under a modified composition search range. A way of modifying the composition search range may include a method for modifying a lower limit to a range of the number of atoms and a method for adding a new range of the number of atoms associated with a new chemical element.

Abstract: There is provided a mass spectrometry data processor allowing for easy selection of a compositional formula for a sample component to be analyzed (analyte) even in general mass spectrometry applications. The mass spectrometry data processor is used to perform a qualitative analysis of the sample component based both on a first mass spectrum obtained by ionizing the sample component by a soft ionization method and on a second mass spectrum generated by cleavage of the sample component.

Abstract: A first mass spectrum including a fragment ion peak is generated under application of a first ionization method. A second mass spectrum including a molecular ion peak is generated under application of a second ionization method. These mass spectra are synthesized to generate a synthesized mass spectrum. On the synthesized mass spectrum, difference information, such as a mass difference and difference composition, is calculated between the molecular ion peak and the fragment ion peak.

Abstract: In a mass spectrometry apparatus, an electric field is applied to an injected specimen to ionize the specimen, and mass spectrometry of the specimen is performed. In an emitter which ionizes the specimen, a flashing process to increase a temperature of the emitter is repeatedly performed at a short-time interval during an injection period of the specimen. A flashing current controller controls a flashing current value to be applied to the emitter to increase, in a long term, a flashing temperature which the emitter reaches in the flashing process.

Abstract: Mass spectrometry for a specimen is repeatedly performed while stepwise changing a parameter (for example, a current value) of an emitter current. Based on a plurality of chromatograms generated by this process, an evaluation value table including a plurality of evaluation values is generated. An individual evaluation value shows a degree of tailing for individual peak included in each chromatogram. A parameter function is generated based on the evaluation value table. The parameter of the emitter current is controlled according to the parameter function.

Abstract: There is provided a mass spectrometry data processor allowing for easy selection of a compositional formula for a sample component to be analyzed (analyte) even in general mass spectrometry applications. The mass spectrometry data processor is used to perform a qualitative analysis of the sample component based both on a first mass spectrum obtained by ionizing the sample component by a soft ionization method and on a second mass spectrum generated by cleavage of the sample component.