Cosmology

Abstract:

A search is presented for stars that may have formed coevally with the apparently young halo star PHL 346. Candidates were selected for spectroscopy from UBR Schmidt Telescope plates in U.K. Schmidt Telescope survey field 603 scanned with the COSMOS facility at the Royal Observatory, Edinburgh. Spectroscopic observations at ∼ 3.5 Å resolution were made of 72 field stars using the 1.9m telescope at the South African Astronomical Observatory; 16 A- and B-type stars were found, one of which had the appropriate spectral type and radial velocity to be associated with PHL 346. Further photometry and spectroscopy confirmed this identification. The remaining low gravity early-type stars have a mean LSR radial velocity of -75 km s-1, consistent with a non-rotating halo Population.

Abstract:

We report on the development of a new method for detecting automatically malignant masses in digitised mammograms, based on a novel non-linear method of multiscale analysis. We show that it is possible to detect > 85 percent of all malignant masses by this method, irrespective of their size, with a false-alarm rate that is close to acceptable for asymptomatic screening.