33,893 research outputs found
Probing Hadronic Structure with The Decay
We compute the branching ratio for and
in chiral perturbation theory and find that
both decays should be observable at CEBAF. With sufficiently low thresholds on
the invariant mass a branching ratio of may be observed
for . For the decay
mode we predict a branching ratio of . The dependence of the
M1 and E2 amplitudes on the momentum transfer will provide a useful test of
chiral perturbation theory which predicts variation over the
allowed kinematic range.Comment: 6 pages, 3 figures, UCSD/PTH 93-06, QUSTH-93-02, Duke-TH-93-4
Recommended from our members
A Generation at Risk: When the baby boomers reach Golden Pond
Hogg Foundation for Mental Healt
Microscopes and computers combined for analysis of chromosomes
Scanning machine CHLOE, developed for photographic use, is combined with a digital computer to obtain quantitative and statistically significant data on chromosome shapes, distribution, density, and pairing. CHLOE permits data acquisition about a chromosome complement to be obtained two times faster than by manual pairing
Improving Drug Safety: The Importance of Postmarking Drug Surveillance
Improved postmarketing surveillance system may reduce the number of adverse reactions to prescription drugs that under the current system continue to rise as the number of prescriptions written in the U.S. rises
Achieving and Maintaining Cognitive Vitality With Aging
This report contains the summary results of a workshop held at Canyon Ranch Health Resort in Tucson, Arizona. Physicians and scientists shed light on the process of cognitive aging. They review current scientific and clinical knowledge of normal human cognitive aging, the biological mechanisms that underlie this process, and risk factors associated with mental decline. They make recommendations for lifestyle changes and outline a research agenda for the development of new therapies to prevent mental decline and maintain cognitive vitality
Biomarkers of Aging: From Primitive Organisms to Man
What biological changes take place as we age? Efforts by scientists to uncover the biomarkers of aging, that is, the normal phenomena of growing old, and to separate these inevitable physiologic changes from diseases and other factors.Warns that alleged "anti-aging" medicines like growth hormone injections are unprovable given current scientific knowledge
Preparing for an Aging Nation: The Need for Academic Geriatricians
According to the author of this issue brief, a strong commitment by the government to a regular stream of financial support for geriatrics would encourage medical centers to establish or expand programs, enhance their ability to attract funds from private sources, and ultimately produce a sufficient number of academic geriatricians. Given the impending retirement of the baby boom generation, this process should begin as soon as possible. This issue brief highlights the critical need for academic geriatricians and presents a realistic proposal to help address the problem
Walk to a Healthy Future
Proposes a new national commitment to walking and formation of walking partnerships and clubs to fight the epidemic of overweight Americans
DI in the outer Galaxy
We report on a deep search with the Westerbork Synthesis Radio Telescope
towards the galactic anticenter for the 327 MHz hyperfine transition of DI.
This is a favorable direction for a search because: (i) the HI optical depth is
high due to velocity crowding; (ii) the observed molecular column density is
low (implying that most of the deuterium would probably be in atomic form,
rather than in HD); and (iii) the stellar reprocessing should be minimal.
Our observations are about a factor of two more sensitive than previous
searches for DI in this direction. We detect a low significance (about 4 sigma)
feature, consistent in both amplitude and center frequency with an emission
feature reported previously (Blitz & Heiles 1987). If this is the DI line, then
the implied N_D/N_H of 3.9+/-1.0 x 10^-5 is comparable to the inferred
pre-solar deuterium abundance. Our observation is consistent with the recent
low measurements of D/H towards high-redshift Lyman-limit systems. On the other
hand, if the reports of high DI abundance (about 24 x 10^-5) in such systems
are confirmed, then our observations imply that even in regions of reduced star
formation within the outer Galaxy, the DI abundance has been reduced by a
factor of about 6 from the primordial abundance.Comment: 4 page LaTeX requires l-aa.sty and psfig.sty, 1 ps figure. Accepted
for publication in A&A Letter
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