Laser spectroscopy for fundamental symmetry tests
(C. H. Li, S. M. Rochester)
measurement of tensor and scalar electric polarizabilities,
lifetimes, branching ratios, and search for new energy levels in atoms
of interest for parity and time-reversal violation experiments and test
of quantum statistics
Searches for parity violation and temporal variation of fundamental "constants" in dysprosium
(A.-T. Nguyen)
Search for parity nonconservation in ytterbium
(J. E. Stalnaker, V. V. Yashchuk, in collaboration with Prof. S. J. Freedman and Prof. D. P. DeMille)
We are carrying out a high-precision measurement of both the
nuclear-spin-independent and the nuclear-spin-dependent
parity-nonconserving (PNC) effects in atomic ytterbium (Yb). While
based on proven experimental techniques, these measruements represent a
radically different approach compared to earlier work in that they use
an atom with an unusually large PNC effect and do not rely on highly
accurate atomic calculations. These measurements will have a
significant impact on our understanding of both the semi-leptonic and
purely hadronic electroweak interactions.
Sensitive magnetometry based on nonlinear magneto-optical rotation
(V. V. Yashchuk, D. F. Kimball, S. M. Rochester, K. R. Kerner)
Some of the sub-projects include:
- NMOR detection of nuclear polarization (with the group of Prof. A. Pines, UC Berkeley Chemistry Dept.)
- New magnetometers for space research (with the group of Dr. V. Angelopolous, Berkeley SSL)
- Investigation of the light-induced atomic desorption (LIAD) from paraffin coatings (with Prof. E. B. Alexandrov and Dr. M. V. Balabas, SPB, Russia)
- Theoretical description of NMOR in paraffin-coated cells (with Dr. A. I. Okunevich, Russia)
Design and construction of the Magnetometer Test Facility (MTF) for characterization of advanced magnetic sensors
(V. V. Yashchuk, M. Solarz, D. F. Kimball, S. M. Rochester)
We are presently constructing a facility for testing and
characterization of newly developed ultra-sensitive magnetometric
sensors. The facility will consist of a state-of-the-art magnetic
shielding and field application/stabilization system, and two of the
currently most sensitive and precise commercial magnetometric systems:
a potassium narrow-line optical pumping super-gradiometer, and a 3-axis
high-Tc superconducting quantum interference device (SQUID). The
facility will be used for quantitative characterization and comparison
of various new sensor types, including those based on nonlinear
magneto-optical rotation, dark-resonance magnetometers, etc., and for
characterization of properties of nominally non-magnetic materials.
Specifications of the Proposed Facility:
The MTF magnetic shield, ready to leave the machine shop for
thermal treatment. The shield is shown with covers off displaying the
four shielding layers. Standing: machinists Dave Nguyen, Pete Thuesen,
and Alex Vaynberg; D. Budker. In front: Dr. Val Yashchuk.
- Axial Alignment: Coil orthogonality better than 0.1°
- Magnetic Constant : 1 Gauss/ampere nominal (in each of the three directions)
- Calibration Accuracy of Magnetic Constant: ± 10-4 % at coil center, for the Earth field range
- Magnetic Field Uniformity : 0.01% gradient in a centrally located 10 cm sphere
- Inner Coil Geometry: Three nested rectangular solenoids using magnetic mirror reflections in the inner shield walls optimized for highest field uniformity
- Inner Coil Dimensions: Available experimental volume of 20"x20"x20"
- Coil Construction: All non-magnetic materials with coils electrically isolated to prevent eddy current loops
- Sensor mounting: Kinematic non-magnetic mounting system with external manual control, and computer-controlled motion activators for vibration and orientation sensitivity characterization.
- Overall system dimensions: The system will occupy a small dedicated laboratory room. The overall dimensions of the outer magnetic coils are 10'x10'x10'.
- Portability: The system as a whole is not designed to be portable, but can be easily transported between laboratories. Parts of the system, including the SQUID 3D sensor, super-gradiometer, and the NMOR-based sensors will be portable with an option of operating in the field.