Question

What happens after a helium flash?
(a) The core quickly heats up and expands
(b) The star breaks apart in a violent explosion
(c) The core suddenly contracts
(d) The core stops fusing helium

Answer 1

Hint: We start by defining what helium flash means. Then proceed to why it occurs and some more details. We then proceed to talk about the processes happening in order for the helium flash to occur and finally ending with the right option.

Complete answer: A helium flash is an exceptionally short warm out of controlled nuclear fusion of huge amounts of helium into carbon through the triple-alpha interaction in the center of low mass stars (between 0.8 solar masses \[M\] and \[2.0M\] during their red giant stage. This outcome in warming up the center and extension of the center happens subsequently.
At the point when the temperature of the center arrives at 300 million degrees, an almost hazardous utilization of the helium happens called the helium flash. During the exceptionally short helium streak (a couple of moments), the star discharges more energy than multiple times the yield of the entire Galaxy. Such pulses might last a couple hundred years, and are thought to occur periodically every 10,000 to 100,000 years. After the flash, helium fusion continues at an exponentially decaying rate for about 40% of the cycle as the helium shell is consumed
In conclusion, the right answer is, option (a) The core quickly heats up and expands.

Note:
The Helium core is degenerate (in low-mass stars), the Helium-consuming response is explosive: a lot of the Helium fuses to Carbon in almost no time. This is known as the Helium Flash, however it isn't discernible, since the photons delivered in the blast are caught in the Hydrogen layers.