Gravitational field of an infinitely long supermassive cosmic string
  We obtain an exact solution of the coupled Einstein-scalar-gauge field equations for a local infinitely long supermassive cosmic string. The solution correponds to that of Hiscock-Gott . The string appears to be due to the freezing of the scalar field at the null value giving rise to a constant linear energy density. 
M.M. Som (UFRJ - Brasil) and Marcelo de Oliveira Souza (UFRJ and UENF   - Brasil)