Non-Scanning Mass Spectrometry Does anyone do mass spectrometry with a magnetic sector to separate ions by mass and an array of detectors in a line to measure the ions? If not, why don't they?

Something like this this setup for measuring the spectrum of light?
Yes, this is called distance-of-flight mass spectrometry. It offers some advantages for large (e.g. biological) molecules and because of its high speed for identifying multiple targets, in chemical and biological warfare.