909 research outputs found
Serendipitous UV source catalogues for 10 years of XMM and 5 years of Swift
Two UV serendipitous source catalogues are presented which were compiled based on the observations with two similar UV telescopes, one being on-board the ESA’s XMM Newton observatory and another—on-board the NASA’s Swift satellite. Both telescopes have similar optical and registration systems providing photometry in three ultraviolet and three visible bands. After processing a 10 years long series of observations from XMM and 5 years from Swift, we have compiled two source catalogues containing more than 4 million sources for XMM and 6 million sources for Swift. We describe the processing algorithms and present catalogue characteristics in comparison with each other
Equilibrium configurations of tripolar charges
It is shown that an ensemble of particles with tripolar (colour) charges will
necessarily cohere in a hierarchy of structures, from simple clusters and
strings to complex aggregates and cyclic molecule-like structures. The basic
combinatoric rule remains essentially the same on different levels of the
hierarchy, thus leading to a pattern of resemblance between different levels.
The number of primitive charges in each structure is determined by the symmetry
of the combined effective potential of this structure. The outlined scheme can
serve as a framework for building a model of composite fundamental fermions.Comment: 22 pages, 12 figure
- …