A method of mass spectrometry is disclosed comprising providing a mixture of different analyte ions and supplying electrons or reagent ions to said mixture so as to transfer charge to the analyte ions. The cover forms an uncovering area where the lever is not covered, and a user can access the lever through the uncovering area. The control section 2 further performs control for switching the execution state of the application program from the non-active state to the rest state, in accordance with a function contained in an application program. A tether guide is provided on an inner surface of the airbag cushion to support the tether, and a sealing means is provided between the vent hole and the tether guide to support the tether, the tether passing through the sealing means. The first and second transistors each comprise a columnar semiconductor portion extending in a direction perpendicular to a semiconductor substrate, a gate-insulating film in contact with a side surface of the columnar semiconductor, and a gate electrode in contact with the gate-insulating film.