ABSTRACT
Despite the tremendous advances in laser cooling of neutral atoms and positive ions, no negatively charged ion has been directly laser cooled. The negative ion of lanthanum, La(-), has been proposed as the best candidate for laser cooling of any atomic anion [ and , Phys. Rev. A 81, 032503 (2010)]. Tunable infrared laser photodetachment spectroscopy is used to measure the bound-state structure of La(-), revealing a spectrum of unprecedented richness with multiple bound-bound electric dipole transitions. The potential laser-cooling transition ((3)F(2)(e)â(3)D(1)(o)) is identified and its excitation energy is measured. The results confirm that La^{-} is a very promising negative ion for laser-cooling applications.
ABSTRACT
The best examples of halo nuclei, exotic systems with a diffuse nuclear cloud surrounding a tightly bound core, are found in the light, neutron-rich region, where the halo neutrons experience only weak binding and a weak, or no, potential barrier. Modern direct-reaction measurement techniques provide powerful probes of the structure of exotic nuclei. Despite more than four decades of these studies on the benchmark one-neutron halo nucleus 11Be, the spectroscopic factors for the two bound states remain poorly constrained. In the present work, the 10Be(d,âp) reaction has been used in inverse kinematics at four beam energies to study the structure of 11Be. The spectroscopic factors extracted using the adiabatic model were found to be consistent across the four measurements and were largely insensitive to the optical potential used. The extracted spectroscopic factor for a neutron in an nâj=2s(1/2) state coupled to the ground state of 10Be is 0.71(5). For the first excited state at 0.32 MeV, a spectroscopic factor of 0.62(4) is found for the halo neutron in a 1p(1/2) state.
ABSTRACT
While final rules clarify many "gray" areas of statutory interpretation under Stark I, some questions of interpretation under this law will remain largely unanswered until further Stark II regulations are issued. Thus, the health care industry is without definitive guidance on many issues. It must continue to make "best guesses" in interpreting the intent of the statute. However, bad guesses could mean imposition of severe penalties, including recoupment and substantial civil money penalties for making prohibited referrals. Moreover, the regulations confirm the Department of Health and Human Services' position that no advisory opinions are available. Because the final regulations were not issued until after the effective dates of the Stark Law, yet another round of restructuring may be required to effect regulatory compliance and avoid imposition of penalties. "Health Law" is a regular feature of Physician Executive from the Washington, D.C., law firm Epstein Becker & Green. Mark Lutes of that law firm serves as editor of the column.
