D. Schafer et Hf. Goenner, The gravitational field of a radiating and contracting spherically-symmetric body with heat flow, GEN RELAT G, 32(11), 2000, pp. 2119-2130
A model of a highly idealized spherically symmetric object radiating away i
ts mass with constant luminosity is presented. The body starts at t = -infi
nity with both infinite mass and radius and contracts to a point at t = 0 w
ithout forming an event horizon. Its material particles are moving non-geod
esically and shearfree while transporting heat to the surface. Unlike in so
me radiating star models of a similar type, all physically required conditi
ons are satisfied in this model.