onion-shell burning structure
Definition: Onion-shell burning structure denotes the physical quantity, process, or model component captured by this lecture-specific statement: Massive stars (≳ 8 M☉) are found, in stellar-evolution models constrained by observed supernova progenitors, to develop successive concentric burning shells (hydrogen, helium, carbon, neon, oxygen, silicon) surrounding an inert iron-peak core, exactly the onion-shell structure this...
Why it matters here: Lecture 12’s Chandrasekhar mass explained why white dwarfs have a maximum mass; this lecture asks what happens to a star whose core exceeds that limit while still actively burning -- the answer, developed here, is the most energetic single event a star can undergo, and the direct origin of the compact-object mass measurements...
Relationships: It is used with iron core to interpret the lecture model. The quantitative connection is the working relation \(E_{\rm binding} \sim \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm core} - \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm remnant}\).
Boundary or common confusion: Describing a core-collapse supernova’s visible explosion as releasing "all" of the star’s available energy. As this lecture’s own order-of-magnitude energy budget shows, the visible kinetic energy and light are only a small fraction (of order 1%) of the total gravitational binding energy released; the great majority of the energy escapes as neutrinos, which...
iron core
Definition: Iron core denotes the physical quantity, process, or model component captured by this lecture-specific statement: Once the iron core’s mass approaches its own effective Chandrasekhar-like limit (reduced from Lecture 12’s pure electron-degenerate value by the additional effects of electron capture and photodisintegration of iron nuclei at these extreme temperatures and densities), electron degeneracy...
Why it matters here: Lecture 12’s Chandrasekhar mass explained why white dwarfs have a maximum mass; this lecture asks what happens to a star whose core exceeds that limit while still actively burning -- the answer, developed here, is the most energetic single event a star can undergo, and the direct origin of the compact-object mass measurements...
Relationships: It is used with onion-shell burning structure, photodisintegration to interpret the lecture model. The quantitative connection is the working relation \(E_{\rm binding} \sim \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm core} - \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm remnant}\).
Boundary or common confusion: Describing a core-collapse supernova’s visible explosion as releasing "all" of the star’s available energy. As this lecture’s own order-of-magnitude energy budget shows, the visible kinetic energy and light are only a small fraction (of order 1%) of the total gravitational binding energy released; the great majority of the energy escapes as neutrinos, which...
photodisintegration
Definition: Photodisintegration denotes the physical quantity, process, or model component captured by this lecture-specific statement: Once the iron core’s mass approaches its own effective Chandrasekhar-like limit (reduced from Lecture 12’s pure electron-degenerate value by the additional effects of electron capture and photodisintegration of iron nuclei at these extreme temperatures and densities), electron degeneracy...
Why it matters here: Lecture 12’s Chandrasekhar mass explained why white dwarfs have a maximum mass; this lecture asks what happens to a star whose core exceeds that limit while still actively burning -- the answer, developed here, is the most energetic single event a star can undergo, and the direct origin of the compact-object mass measurements...
Relationships: It is used with iron core, core collapse to interpret the lecture model. The quantitative connection is the working relation \(E_{\rm binding} \sim \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm core} - \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm remnant}\).
Boundary or common confusion: Describing a core-collapse supernova’s visible explosion as releasing "all" of the star’s available energy. As this lecture’s own order-of-magnitude energy budget shows, the visible kinetic energy and light are only a small fraction (of order 1%) of the total gravitational binding energy released; the great majority of the energy escapes as neutrinos, which...
core collapse
Definition: Core collapse denotes the physical quantity, process, or model component captured by this lecture-specific statement: Once the iron core’s mass approaches its own effective Chandrasekhar-like limit (reduced from Lecture 12’s pure electron-degenerate value by the additional effects of electron capture and photodisintegration of iron nuclei at these extreme temperatures and densities), electron degeneracy...
Why it matters here: Lecture 12’s Chandrasekhar mass explained why white dwarfs have a maximum mass; this lecture asks what happens to a star whose core exceeds that limit while still actively burning -- the answer, developed here, is the most energetic single event a star can undergo, and the direct origin of the compact-object mass measurements...
Relationships: It is used with photodisintegration, neutronization to interpret the lecture model. The quantitative connection is the working relation \(E_{\rm binding} \sim \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm core} - \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm remnant}\).
Boundary or common confusion: Describing a core-collapse supernova’s visible explosion as releasing "all" of the star’s available energy. As this lecture’s own order-of-magnitude energy budget shows, the visible kinetic energy and light are only a small fraction (of order 1%) of the total gravitational binding energy released; the great majority of the energy escapes as neutrinos, which...
neutronization
Definition: Neutronization denotes the physical quantity, process, or model component captured by this lecture-specific statement: Once the iron core’s mass approaches its own effective Chandrasekhar-like limit (reduced from Lecture 12’s pure electron-degenerate value by the additional effects of electron capture and photodisintegration of iron nuclei at these extreme temperatures and densities), electron degeneracy...
Why it matters here: Lecture 12’s Chandrasekhar mass explained why white dwarfs have a maximum mass; this lecture asks what happens to a star whose core exceeds that limit while still actively burning -- the answer, developed here, is the most energetic single event a star can undergo, and the direct origin of the compact-object mass measurements...
Relationships: It is used with core collapse, core-bounce shock to interpret the lecture model. The quantitative connection is the working relation \(E_{\rm binding} \sim \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm core} - \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm remnant}\).
Boundary or common confusion: Describing a core-collapse supernova’s visible explosion as releasing "all" of the star’s available energy. As this lecture’s own order-of-magnitude energy budget shows, the visible kinetic energy and light are only a small fraction (of order 1%) of the total gravitational binding energy released; the great majority of the energy escapes as neutrinos, which...
core-bounce shock
Definition: Core-bounce shock denotes the physical quantity, process, or model component captured by this lecture-specific statement: Collapse halts abruptly once the core reaches nuclear density (where the strong nuclear force itself, not electron degeneracy, provides pressure support), producing a rebounding shock wave; while the shock alone often stalls, the enormous flux of neutrinos streaming out of the newly...
Why it matters here: Lecture 12’s Chandrasekhar mass explained why white dwarfs have a maximum mass; this lecture asks what happens to a star whose core exceeds that limit while still actively burning -- the answer, developed here, is the most energetic single event a star can undergo, and the direct origin of the compact-object mass measurements...
Relationships: It is used with neutronization, neutrino-driven explosion to interpret the lecture model. The quantitative connection is the working relation \(E_{\rm binding} \sim \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm core} - \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm remnant}\).
Boundary or common confusion: Describing a core-collapse supernova’s visible explosion as releasing "all" of the star’s available energy. As this lecture’s own order-of-magnitude energy budget shows, the visible kinetic energy and light are only a small fraction (of order 1%) of the total gravitational binding energy released; the great majority of the energy escapes as neutrinos, which...
neutrino-driven explosion
Definition: Neutrino-driven explosion denotes the physical quantity, process, or model component captured by this lecture-specific statement: Collapse halts abruptly once the core reaches nuclear density (where the strong nuclear force itself, not electron degeneracy, provides pressure support), producing a rebounding shock wave; while the shock alone often stalls, the enormous flux of neutrinos streaming out of the newly...
Why it matters here: Lecture 12’s Chandrasekhar mass explained why white dwarfs have a maximum mass; this lecture asks what happens to a star whose core exceeds that limit while still actively burning -- the answer, developed here, is the most energetic single event a star can undergo, and the direct origin of the compact-object mass measurements...
Relationships: It is used with core-bounce shock to interpret the lecture model. The quantitative connection is the working relation \(E_{\rm binding} \sim \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm core} - \dfrac{3}{5}\dfrac{GM^{2}}{R}\bigg|_{\rm remnant}\).
Boundary or common confusion: Describing a core-collapse supernova’s visible explosion as releasing "all" of the star’s available energy. As this lecture’s own order-of-magnitude energy budget shows, the visible kinetic energy and light are only a small fraction (of order 1%) of the total gravitational binding energy released; the great majority of the energy escapes as neutrinos, which...