We study 1/2 Bogomol'nyi-Prasad-Sommerfield (BPS) domain walls, 1/2 BPS flux tubes (strings), and their 1/4 BPS junctions. We consider the simplest example of N=2 Abelian gauge theory with two charged matter hypermultiplets which contains all of the above-listed extended objects. In particular, we focus on string-wall junctions (boojums) and calculate their energy. It turns out to be logarithmically divergent in the infrared domain. We compute this energy first in the (2+1)-dimensional effective theory on the domain wall and then, as a check, obtain the same result from the point of view of (3+1)-dimensional bulk theory. Next, we study interactions of boojums considering all possible geometries of string-wall junctions and directions of the string magnetic fluxes.
|Original language||English (US)|
|Number of pages||10|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - Jul 15 2005|