Magnetic field dependence of muonium-antimuonium conversion
Abstract We study the magnetic field dependence of muonium-antimuonium conversion for all relevent operators, such as ( V − A ) ( V − A ), ( V − A ) ( V + A ), SS and PP . The traditional ( V − A ) ( V − A ) interaction suffers two stage quenching and becomes strongly suppressed by 10 3 Gauss fields or higher. In contrast, all other operator types (except ( S − P ) ( S − P )) have a weaker field dependence and in general are not strongly quenched by strong fields. Since ongoing experiments are done with sizable magnetic fields, our results are useful for the interpretation of experimental results as bounds on different effective interactions.
Improved upper limit on muonium to antimuonium conversion
A new experiment has been set up at the Paul Scherrer Institut to search for muonium to antimuonium conversion. No event was found to fulfil the requested signature which consists of the coincident detection of both constituents of the antiatom in its decay. Assuming an effective (V - A) x (V - A) type interaction an improved upper limit is established for the conversion probability of P() less than or equal to 8 x 10(-9) (90% C.L.), which is almost 2 orders of magnitude lower compared to previous results and provides a sensitive test for theoretical extensions of the standard model.
Global Occupational Health Issues
1. Occupational health problems in developing countries are more widespread and serious because they occur against a background of endemic risk factors for ill health. 2. In general, developing countries have less adequately developed occupational health personnel and programs and less adequately developed and enforced laws and regulations than developed countries. 3. Awareness of the importance of occupational health among workers, management, government officials, and the public is increasing with developing countries. 4. Occupational health professionals in developed countries can contribute in many ways to improving occupational health in developing countries.