2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/5563Numerical modeling of shock breakout in compact presupernovae of type Ib/c is done by two independent methods. Peak color temperatures reach 4 to 8 million K for explosion energies 1 to 9 foe with a typical local time-scale of 0.03 seconds. In the obverver's frame the burst is smeared over few seconds due to light travel time correction R/c.4 pages 4 figures. 11th Workshop on "Nuclear Astrophysics", Ringberg Castle, Tegernsee, Germany, February 11-16, 2002. Minor correctionsAstrophysicstext