helium flash Comparison Table

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helium flash comparison table

Subject has definition has minimum temperature is a kind of

helium burning The stage when a star fuses helium into carbon and oxygen. All stars born with more than half a solar mass eventually burn helium. exothermic fusion process

helium flash The onset of runaway helium burning under degenerate conditions. The helium flash occurs in the hydrogen-exhausted core of a star in the red-giant phase of evolution. When gravitational pressure has brought the degenerate core to a temperature of about 10⁸ K, the helium nuclei can start to undergo thermonuclear reactions. Once the helium burning has started, the temperature builds up rapidly (without a cooling, stabilizing expansion), and the extreme sensitivity of the nuclear reaction rate to temperature causes the helium-burning process to accelerate. This in turn raises the temperature, which further accelerates the helium burning, until a point is reached where the thermal pressure expands the core and thus removes the degeneracy and limits the flash. The helium flash can only occur when the helium core is less than the 1.4 M_sun Chandrasekhar mass limit and thus it is restricted to low-mass stars. 10⁸ K helium burning

Subject	has definition	has minimum temperature	is a kind of
helium burning	The stage when a star fuses helium into carbon and oxygen. All stars born with more than half a solar mass eventually burn helium.		exothermic fusion process
helium flash	The onset of runaway helium burning under degenerate conditions. The helium flash occurs in the hydrogen-exhausted core of a star in the red-giant phase of evolution. When gravitational pressure has brought the degenerate core to a temperature of about 10⁸ K, the helium nuclei can start to undergo thermonuclear reactions. Once the helium burning has started, the temperature builds up rapidly (without a cooling, stabilizing expansion), and the extreme sensitivity of the nuclear reaction rate to temperature causes the helium-burning process to accelerate. This in turn raises the temperature, which further accelerates the helium burning, until a point is reached where the thermal pressure expands the core and thus removes the degeneracy and limits the flash. The helium flash can only occur when the helium core is less than the 1.4 M_sun Chandrasekhar mass limit and thus it is restricted to low-mass stars.	10⁸ K	helium burning

Next helium burning: helium shell flash Up: helium burning