The Thermo scientific Exactive Plus is the newest instrument of the mass spectrometry center.  The purpose of the  Exactive Plus is to precisely measure masses accurately.  The instrument is based on the orbitrap mass analyzer, which is a purely electrostatic trap, consisting of a cyclindical outer electrode and a barrell inner electrode that hold DC potentials to trap the ions in circular orbits around the inner electrodes.   The ions are collected in a device called a c-trap, which is an electrostatic trap in the shape of a C.  The ions from the C-trap are then injected simultanously into the orbitrap off axis.  The ions than undergo axial motion at frequency related to the square route of the m/z of the ions.   The frequency of the motion is measured to provide the m/z of the ions.  The instrument is capable of resolutions up to 140,000 at m/z 200.   The mass range of the instrument is up to 6000.