What would happen if 10^37 J of energy was dumped into the sun via antimatter detonation?

My first post here, and it's more about destroying worlds than making them.

Consider this scenario:

An earthlike planet where a powerful magic spell has been cast, protecting all positrons from annihilation on contact with regular matter. Stable antimatter can finally exist (in a sense). And positronium finds itself an array of useful applications, including weapons exchanges with parallel universes (which don't share the same protective field).

Something these wizards failed to account for was this protective field expanding outwards at the speed of light. 7 minutes after the spell was cast, positrons began to build up in the planet's sunlike star. The proton-proton fusion reaction at its core becomes about 5% less energetic, as it was fuelled in part by electron-positron annihilation. This goes wholly unnoticed for a while due to the 1000-year half life it takes for heat to reach the sun's surface.

Some time later, let's say 10,000 years, a terrorist group called the Curse Breakers disables the spell. All stored positronium detonates immediately. But 14 minutes later, the survivors of this blast bear witness an even greater cosmic catastrophe - the destruction of their sun.

What I'm asking is this: how big a boom would there be? How fast would it happen?

If my calculations are correct, the thick shell of positrons around the core would contain 6.28x10^36 joules. With this energy released in a tiny fraction of a second, could the star undergo a helium flash? Runaway fusion at its core? Maybe even a supernova?

(If not, how long would the spell need to last to generate enough positrons?)

Edit: And what effects would be felt on the planet, assuming it is earthlike and orbits at 1 AU?

posted over 6 years ago

Jynto‭

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