An ion trap storage/time‐of‐flight mass spectrometer

An ion trap/time‐of‐flight (TOF) mass spectrometer combination has been developed in order to combine the storage capabilities of an ion trap with the speed and resolution of a time‐of‐flight device. The ion trap is an rf quadrupole trap which operates in the total storage mode, i.e., with the dc voltage=0 on the end caps and rf voltage on the ring electrode. The trap has an ion storage time of ≥2 s at an rf potential of 310 Vpp. The stored ions are ejected into the time‐of‐flight device using a −150 V dc pulse on the exit end cap which causes the ion trajectories in the trap to become unstable. The ions are mass analyzed using either a linear or reflectron TOF. In the linear mode the resolution is 240 while in the reflectron mode a resolution of 1300 at m/z 93 is achieved. The storage capabilities of this device may have important applications towards enhancing sensitivity, the study of very slow metastable decay, and photodissociation mass spectrometry and spectroscopy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70469/2/RSINAK-63-10-4277-1.pd