| 摘要 |
A measurement condition storage unit (31) that is built into a control unit (30) stores a CID gas condition table (31a) that indicates the relationship between the scanning speed of mass scanning in a pre-stage quadrupole mass filter (3) and CID gas supply pressure. If the scanning speed is high, the impact of ion speed reduction due to collision with CID gas in a collision cell (4) becomes relatively large. Consequently, an appropriate CID gas supply pressure for each scanning speed is searched for beforehand and stored in the CID gas condition table (31a) so that the collapse of the waveform of the peak on a mass spectrum becomes small and ion strength becomes as high as possible. When measuring the target sample, if a precursor ion scan measurement mode or the like is designated, the CID gas supply pressure according to the scanning speed at the time is obtained on the basis of the CID gas condition table (31a), and a CID gas supply unit (8) is controlled. Thus, regardless of the scanning speed, a mass spectrum for which peak separability is high and sensitivity is good can be obtained. |
