Continuous density measurement of atomic hydrogen by means of a bolometer

We developed a device which allows continuous measurement of the density of low‐temperature stabilized atomic hydrogen by means of a bolometer. This density monitor was tested in a large open‐storage cell during microwave‐induced extraction of polarized atoms.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70391/2/RSINAK-62-1-251-1.pd

Transdermal Iontophoretic Delivery of Vapreotide Acetate AcrossPorcine Skin in Vitro

Purpose: The purpose of this study was to evaluate the feasibility of delivering vapreotide, a somatostatin analogue, by transdermal iontophoresis. Methods: In vitro experiments were conducted using dermatomed porcine ear skin and heat-separated epidermis. In addition to quantifying vapreotide transport into and across the skin, the effect of peptide delivery on skin permselectivity was also measured. The influence of (1) current density, (2) pre- and post-treatment of the skin, (3) competitive ions, and (4) inclusion of albumin in the receptor on vapreotide delivery were investigated. Results: Epidermis proved to be a better model than dermatomed skin for vapreotide transport studies. Despite the susceptibility of vapreotide to enzymatic degradation, a flux of 1.7μg/cm2 per hour was achieved after 7h of constant current iontophoresis (0.15mA/cm2). Post-iontophoretic extraction revealed that, depending on the experimental conditions, 80-300μg of peptide were bound to the skin. Vapreotide was found to interact with the skin and displayed a current-dependent inhibition of electroosmosis. However, neither the pre-treatment strategies to saturate the putative binding sites nor the post-treatment protocols to displace the bound peptide were effective. Conclusion: Based on the observed transport rate of vapreotide across porcine epidermis and its clinical pharmacokinetics, therapeutic concentrations should be achievable using a 15-cm2 patc

Cryopumping of atomic hydrogen

The pumping speed for the cryopumping of an atomic hydrogen beam was measured. Measurements were made for cryocondensation, cryosorption, and differential pumping. The pumping speed for atomic hydrogen was observed to be much smaller than the pumping speed for molecular hydrogen. It is believed that this is due to the energy released during the recombination of the atomic hydrogen.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69754/2/RSINAK-62-11-2738-1.pd

A Monitor of Beam Polarization Profiles for the TRIUMF Parity Experiment

TRIUMF experiment E497 is a study of parity violation in pp scattering at an energy where the leading term in the analyzing power is expected to vanish, thus measuring a unique combination of weak-interaction flavour conserving terms. It is desired to reach a level of sensitivity of 2x10^-8 in both statistical and systematic errors. The leading systematic errors depend on transverse polarization components and, at least, the first moment of transverse polarization. A novel polarimeter that measures profiles of both transverse components of polarization as a function of position is described.Comment: 19 pages LaTeX, 10 PostScript figures. To appear in Nuclear Instruments and Methods in Physics Research, Section

Study of a Depolarizing Resonance at the IUCF Cooler Ring

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Siberian Snake and Depolarizing Resonance Studies at the Cooler Ring

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Microwave driven extraction of stabilized spin polarized atomic hydrogen

The storage of ultracold spin-polarized hydrogen atoms offers the possibility of producing a high intensity nuclear polarized atomic hydrogen jet. We stored electron spin polarized atomic hydrogen at 0.4 K in an open 5 T magnetic storage cell. We also observed directly, for the first time, the extraction of hydrogen atoms from the storage cell by flipping their spins using a microwave driven transition. The results are being used to design a high intensity jet of nuclear polarized atomic hydrogen to be used as an internal target in the 400 GeV to 3 TeV UNK accelerator.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29451/1/0000533.pd

Investigation of the nucleon-nucleon tensor force in the three-nucleon system

Proton-deuteron elastic scattering has been investigated at Ep =22.7 MeV by comparison of rigorous Faddeev calculations with experimental results. The observable most sensitive to the tensor force is the nucleon-nucleon polarization transfer coefficient Kyy'. The new angular distribution of Kyy' clearly favours the tensor force of the Bonn A potential, which is weaker than the one of the Paris potential.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28425/1/0000208.pd

Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters