Magnetic sector analyzer magnet scan

Mass range is the m/z range of the mass analyzer. For example, quadrupole analyzers typically only scan up to m/z 3000, magnetic sector analyzers can go to m/z 10 000, and time-of-flight analyzers have virtually unlimited m/z. 

Combinations of magnetic and electrostatic analyzers have been used to make instruments with high resolution capable (with appropriate calibration) of accurate mass measurements. Because they are scanning instruments, magnetic sector analyzers suffer from duty cycle limitations, as do quadrupole analyzers. Furthermore, because the scan speed of the magnetic field is proportional to resolution, additional time is required to obtain a spectrum as resolution is increased. Scanning the... 

An IRMS system (which is essentially a magnetic sector analyzer with an electron impact source) has multiple detectors or collectors, very similar in design to a Faraday cup, which is in place for each isotopomer enabling very high isotopic precision [98]. IRMS systems measure isotope ratios extremely precisely compared with conventional scanning molecular MS systems. 

Scanning techniques are carried out differently with such hybrid instruments as the triple quadrupole analyzer, the Q/TOF (quadrupole and time-of-flight), and double magnetic-sector instruments. 

The most common modes of operation for ms/ms systems include daughter scan, parent ion scan, neutral loss scan, and selected reaction monitoring. The mode chosen depends on the information required. Stmctural identification is generally obtained using daughter or parent ion scan. The mass analyzers commonly used in tandem systems include quadmpole, magnetic-sector, electric-sector, time-of-flight, and ion cyclotron resonance. Some instmments add a third analyzer such as the triple quadmpole ms (27). 

Rapid scanning mass spectrometers providing unit resolution are routinely used as chroaatographic detectors. Ion separation is accomplished using either a magnetic sector, quadrupole filter or ion trap device. Ions can also be separated by time-of-flight or ion cyclotron resonance mass analyzers but these devices are not widely used with chromatograidiic inlets and will not be discussed here [20]. 

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