Gießen 2007 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
HK: Fachverband Physik der Hadronen und Kerne
HK 47: Instrumentation und Anwendungen
HK 47.5: Talk
Thursday, March 15, 2007, 15:15–15:30, F
Isobaric separation by a multiple-reflection time-of-flight mass spectrometer — •Timo Dickel1, Ulrich Czok1, Hans Geissel1,2, Christian Jesch1, Martin Petrick1, Wolfgang Plaß1, and Christoph Scheidenberger1,2 — 1II. Physikalisches Institut, Justus-Liebig-Universität Giessen — 2GSI, Darmstadt
Time-of-flight mass spectrometers (TOF-MS) are novel tools for direct mass measurement and separation of exotic nuclei, because of their short cycle time, large mass window and high mass resolving power. The short analysis time will allow measurements of very short-lived nuclei (ca. 1 ms) and operation with up to 10 millions ions per second. Thus it can be used as an isobar separator for nuclear spectroscopy and as fast pre-separator for Penning trap experiments under conditions with strong isobaric contaminations.
As proof-of-principle a multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) has been developed. It consists of an electron-impact ion source, two electrostatic reflectors and an MCP-detector. For the use of the MR-TOF-MS as an isobar separator the temporal separation of ions has to be converted into a spatial separation by in a pulsed ion gate, which has been realized as a Bradbury-Nielson-Gate.
For the MR-TOF-MS a mass resolving power of 60,000 has been achieved; a maximum transmission efficiency of 70 % has been estimated. If the MR-TOF-MS is used as separator, its resolving power is half as large as that for mass measurement.