A cooled white dwarf is a black dwarf.
I think you are thinking of a neutron star which has nothing to do with a white dwarf.
A white dwarf is much larger than a neutron star.
Once a medium sized star has consumed all it's fuel it becomes a White Dwarf star (just the extremely dense core of the original star remains composed mainly of carbon). A White Dwarf star will, however, eventually lose it's heat to become a Black Dwarf.
A white dwarf is several hundred billion times denser than the average density of the sun.
The obvious reason is that the specific star has bigger density compared with the Sun. For example, that star could be a "white dwarf star". A white dwarf mostly contains "electron degenerate matter", which is very dense. A white dwarf is a small dense star.
A star that has undergone expansion, deflation and cooling is known as a white dwarf, or degenerate dwarf. It is a small star made up of mainly electron-degenerate matter.
White dwarf
A white dwarf is much larger than a neutron star.
White dwarf
Once a medium sized star has consumed all it's fuel it becomes a White Dwarf star (just the extremely dense core of the original star remains composed mainly of carbon). A White Dwarf star will, however, eventually lose it's heat to become a Black Dwarf.
A white dwarf is several hundred billion times denser than the average density of the sun.
A white dwarf is the remains of an old star, but they still remain very hot and will continue to shine as a white dwarf for many millions of years until they gradually cool off to become black dwarfs. They are very dense.
white dwarf
white dwarf
Most likely it would be a "white dwarf". They are composed mainly of carbon and oxygen in an extremely dense form, called "electron degenerate matter".
The obvious reason is that the specific star has bigger density compared with the Sun. For example, that star could be a "white dwarf star". A white dwarf mostly contains "electron degenerate matter", which is very dense. A white dwarf is a small dense star.
They are opposites a white is very dense like the Sun & brown insufficiently dense to form a reaction. Details both too lengthy to post here so search brown dwarf wikipedia & do the same with white & you will be bombarded with info.
It is not believed that any black dwarfs exist yet, as the universe is not old enough for a white dwarf to have cooled into one.