Berlin 2005 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
MS: Massenspektrometrie
MS 2: Posterbeiträge
MS 2.3: Poster
Freitag, 4. März 2005, 11:45–12:30, Poster HU
Carbon Cluster Ion Source for Absolute Mass Measurements at SHIPTRAP — •A. Chaudhuri — Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, D-17487, Germany
Carbon clusters are the mass reference of choice for SHIPTRAP, a Penning trap mass spectrometer for precision mass measurements of very heavy elements at GSI [1]. The cluster ions are produced by means of laser induced desorption, fragmentation and ionization of Sigradur®. A precision mass measurement is carried out by determining the ion cyclotron frequency ωc = qB/m, where q/m is the charge to mass ratio of the ion and B is the magnetic field in the precision trap. The unknown mass of the ion of interest is obtained from the comparison of its cyclotron frequency ωc with that of a well known reference mass. Since the unified atomic mass unit is defined as 1/12 of the mass of the 12C atom thus the masses of carbon clusters are exact multiples of the unified atomic mass unit (the atomic binding energies can be neglected) and their use as reference ions will allow absolute mass measurements at SHIPTRAP. In addition the systematic error will be determined by cross reference mass measurements between carbon clusters of different size [2]. References 1. J. Dilling et al., Hyp. Int. 127, 491 (2000) 2. A. Kellerbauer et al., Eur. Phys. J. D 22, 53-64 (2003)