
Accelerator
Mass Spectrometry at the
Gas-filled
Analyzing Magnet System GAMS
Accelerator mass
spectrometry (AMS) offers the possibility to measure minute
concentrations
of long-lived radionuclides (e.g. 60Fe, T1/2 =
1.49
My) by counting single ions. The stripping process in the terminal foil
of the tandem accelerator causes a breakup of molecules, which allows a
highly effective reduction of molecular background. Therefore, the
sensitivity
of AMS is limited by the background due to the stable isobar (60Ni)
and the stable isotopes (54,56,57,58Fe).
GAMS is an AMS
system optimized for background reduction and for efficiency, and
thus
allows determinations of long-lived radionuclides at highest
sensitivity
levels.
Additionally
to
the isobar rejection by a multi
delta
E ionization chamber, further separation is done in a gas-filled
magnet,
taking advantage of the Z dependence of the
average charge state of ions in gas. Supplementary isotope reduction is
achieved by means of a Wien velocity filter and a
time-of-flight
path.
These
measures,
together with the high energies available at the Munich
MP tandem, enable the most sensitive measurements of long-lived
radionuclides
with 30 < A < 100, like 36Cl, 41Ca, 53Mn,
59Ni,
60Fe,
63Ni,
79Se ...
scientific highlights:
Supernovaproduced 60Fe
on Earth (english / deutsch)
63Ni from
Hiroshima (english / deutsch)
publications
staff
Accelerator
Laboratory of the LMU and TU Munich
Festkolloquium anlässlich des 85. Geburtstags
von Herrn Prof.Dr. H. Morinaga
Fotogalerie
Teil 1
Teil 2
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