There's a bit of a misunderstanding in your question. White dwarf stars are formed when a star like our Sun exhausts its nuclear fuel and sheds its outer layers, leaving behind a dense core.

White dwarfs do not form after a supernova. Supernovas are powerful explosions that occur when massive stars (much larger than our Sun) reach the end of their lives. These explosions leave behind either a neutron star or a black hole, not a white dwarf.

Here's a breakdown:

* White dwarfs: Formed from the core of low to medium mass stars (like our Sun). They are very dense but not formed after a supernova.

* Neutron stars: Formed after a supernova of massive stars. They are incredibly dense, with a teaspoonful of neutron star material weighing billions of tons.

* Black holes: Formed after a supernova of the most massive stars. They are so dense that not even light can escape their gravitational pull.

So, while a white dwarf is a dense and tiny star, it is not the remnant of a supernova.