17 research outputs found
Isotope shifts of 6s5d D-states in neutral Barium
Laser spectroscopy of the low lying P and D states in atomic barium
has been performed. This work contributes substantially to the development of
an effective laser cooling and trapping for heavy alkaline earth elements and
aims in particular for a better understanding of the atomic wave function of
these systems. Isotope shifts and hyperfine structures are ideal probes for the
wave functions at the position of the nucleus. This is essential input for a
theoretical evaluation of the sensitivity to fundamental symmetry breaking
properties like permanent electric dipole moments. We report the first isotope
shift measurements of the D-P transitions. A deviation of
the King plot from its expected behavior has been observed. Further we have
optically resolved the hyperfine structure of the D states.Comment: 7 pages, 7 figure
Magneto optical trapping of Barium
First laser cooling and trapping of the heavy alkaline earth element barium
has been achieved based on the strong 6s S - 6s6p P
transition for the main cooling. Due to the large branching into metastable
D-states several additional laser driven transitions are required to provide a
closed cooling cycle. A total efficiency of for slowing
a thermal atomic beam and capturing atoms into a magneto optical trap was
obtained. Trapping lifetimes of more than 1.5 s were observed. This lifetime is
shortened at high laser intensities by photo ionization losses. The developed
techniques will allow to extend significantly the number of elements that can
be optically cooled and trapped.Comment: 4 pages, 5 figure
Aspects of Cooling at the TRIP Facility
The TriP facility at KVI is dedicated to provide short lived radioactive
isotopes at low kinetic energies to users. It comprised different cooling
schemes for a variety of energy ranges, from GeV down to the neV scale. The
isotopes are produced using beam of the AGOR cyclotron at KVI. They are
separated from the primary beam by a magnetic separator. A crucial part of such
a facility is the ability to stop and extract isotopes into a low energy
beamline which guides them to the experiment. In particular we are
investigating stopping in matter and buffer gases. After the extraction the
isotopes can be stored in neutral atoms or ion traps for experiments. Our
research includes precision studies of nuclear -decay through
- momentum correlations as well as searches for permanent electric
dipole moments in heavy atomic systems like radium. Such experiments offer a
large potential for discovering new physics.Comment: COOL05 Workshop, Galena, Il, USA, 18-23. Sept. 2005, 5 pages, 3
figure
Development of a thermal ionizer as ion catcher
An effective ion catcher is an important part of a radioactive beam facility
that is based on in-flight production. The catcher stops fast radioactive
products and emits them as singly charged slow ions. Current ion catchers are
based on stopping in He and H gas. However, with increasing intensity of
the secondary beam the amount of ion-electron pairs created eventually prevents
the electromagnetic extraction of the radioactive ions from the gas cell. In
contrast, such limitations are not present in thermal ionizers used with the
ISOL production technique. Therefore, at least for alkaline and alkaline earth
elements, a thermal ionizer should then be preferred. An important use of the
TRIP facility will be for precision measurements using atom traps. Atom
trapping is particularly possible for alkaline and alkaline earth isotopes. The
facility can produce up to 10 s of various Na isotopes with the
in-flight method. Therefore, we have built and tested a thermal ionizer. An
overview of the operation, design, construction, and commissioning of the
thermal ionizer for TRIP will be presented along with first results for
Na and Na.Comment: 10 pages, 4 figures, XVth International Conference on Electromagnetic
Isotope Separators and Techniques Related to their Applications (EMIS 2007
Standard Model tests with trapped radioactive atoms
We review the use of laser cooling and trapping for Standard Model tests,
focusing on trapping of radioactive isotopes. Experiments with neutral atoms
trapped with modern laser cooling techniques are testing several basic
predictions of electroweak unification. For nuclear decay, demonstrated
trap techniques include neutrino momentum measurements from beta-recoil
coincidences, along with methods to produce highly polarized samples. These
techniques have set the best general constraints on non-Standard Model scalar
interactions in the first generation of particles. They also have the promise
to test whether parity symmetry is maximally violated, to search for tensor
interactions, and to search for new sources of time reversal violation. There
are also possibilites for exotic particle searches. Measurements of the
strength of the weak neutral current can be assisted by precision atomic
experiments using traps of small numbers of radioactive atoms, and sensitivity
to possible time-reversal violating electric dipole moments can be improved.Comment: 45 pages, 17 figures, v3 includes clarifying referee comments,
especially in beta decay section, and updated figure
TRIμP - A radioactive-atom trapping facility at KVI
The TRIμP facility, under construction at KVI, requires the production and separation of short-lived and rare isotopes. For this purpose, we have designed, constructed and commissioned a versatile magnetic separator that allows efficient injection into an ion catcher, i.e., gas-filled stopper/cooler or thermal ionizer, from which a low energy radioactive beam will be extracted. These nuclides will be transported to atomic traps for precision experiments that may test the Standard Model
Aspects of cooling at the TRI mu P facility
The Tri mu P facility at KVI is dedicated to provide short lived radioactive isotopes at low kinetic energies to users. It comprised different cooling schemes for a variety of energy ranges, from GeV down to the neV scale. The isotopes are produced using beam of the AGOR cyclotron at KVI. They are separated from the primary beam by a magnetic separator. A crucial part of such a facility is the ability to stop and extract isotopes into a low energy beamline which guides them to the experiment. In particular we are investigating stopping in matter and buffer gases. After the extraction the isotopes can be stored in neutral atoms or ion traps for experiments. Our research includes precision studies of nuclear beta-decay through beta-v momentum correlations as well as searches for permanent electric dipole moments in heavy atomic systems like radium. Such experiments offer a large potential for discovering new physics