Lecture 15, PPT version
... • Extraordinarily bright, so can use them to measure distances to galaxies that are very far away: b = L / (4 d2) • Supernovae are the source of all heavy chemical elements! • The heavy chemical elements are produced during the explosion itself, when there is more than enough energy to fuse nuclei ...
... • Extraordinarily bright, so can use them to measure distances to galaxies that are very far away: b = L / (4 d2) • Supernovae are the source of all heavy chemical elements! • The heavy chemical elements are produced during the explosion itself, when there is more than enough energy to fuse nuclei ...
Diapositive 1 - Theoretical Astro-, Nuclear
... Light nuclei (typically A < 20, pp chain, CNO) or close to the drip lines (hot burning) ...
... Light nuclei (typically A < 20, pp chain, CNO) or close to the drip lines (hot burning) ...
Radioactivity and man
... All matter that surrounds us is made up of atoms. Every atom consists of protons and neutrons, which together form the nucleus, surrounded by a cloud of negatively-charged electrons. Within the atom, the nucleus is made up of positively charged protons and by neutrons that lack electric charge and a ...
... All matter that surrounds us is made up of atoms. Every atom consists of protons and neutrons, which together form the nucleus, surrounded by a cloud of negatively-charged electrons. Within the atom, the nucleus is made up of positively charged protons and by neutrons that lack electric charge and a ...
Stellar Evolution
... to type II and Ib, only difference is whether or not star sheds outer hydrogen layer before exploding ...
... to type II and Ib, only difference is whether or not star sheds outer hydrogen layer before exploding ...
How are stars formed
... The most massive stars have biggest tanks of fuel, but burn it much more quickly (like a Hummer) The least massive stars have smallest fuel reserves, but burn it very slowly by comparison (like a Moped) Difference in rate of fuel consumption so great that more massive stars exhaust fuel and die much ...
... The most massive stars have biggest tanks of fuel, but burn it much more quickly (like a Hummer) The least massive stars have smallest fuel reserves, but burn it very slowly by comparison (like a Moped) Difference in rate of fuel consumption so great that more massive stars exhaust fuel and die much ...
Sample Midterm - IUPUI Physics
... does the energy that a star needs to survive come from (before it starts to fuse Helium) and how does that affect the size and temperature of the surface of the star? B) What is the process by which Helium (also known as alpha particles) are fused into another element and what element is created fro ...
... does the energy that a star needs to survive come from (before it starts to fuse Helium) and how does that affect the size and temperature of the surface of the star? B) What is the process by which Helium (also known as alpha particles) are fused into another element and what element is created fro ...
Test 3 Review
... billion years ago. As Milky Way ages, the abundances of elements compared to H in gas and new stars are increasing due to fusion and supernovae. Elements up to iron (56Fe, 26 p + 30 n in nucleus) produced by steady fusion (less abundant elements we didn’t discuss, like Cl, Na, made in reactions that ...
... billion years ago. As Milky Way ages, the abundances of elements compared to H in gas and new stars are increasing due to fusion and supernovae. Elements up to iron (56Fe, 26 p + 30 n in nucleus) produced by steady fusion (less abundant elements we didn’t discuss, like Cl, Na, made in reactions that ...
Emergent structures
... when a number of simple entities (agents) operate in an environment, forming more complex behaviours as a collective Emergent structures are patterns not created by a single event or rule. There is nothing that commands the system to form a pattern, but instead the interactions of each part to its i ...
... when a number of simple entities (agents) operate in an environment, forming more complex behaviours as a collective Emergent structures are patterns not created by a single event or rule. There is nothing that commands the system to form a pattern, but instead the interactions of each part to its i ...
Stellar Structure — Polytrope models for White Dwarf density profiles
... taken to be almost at r = 0 (not quite at r = 0 as RHS of Eq. (6) diverges there). Take this small value of r to be r = δ. Then the mass boundary condition is trivial, m(δ) = 0. This leaves only one non-trivial boundary condition, ρ(δ), i.e., the mass density at the centre of the white dwarf. As a f ...
... taken to be almost at r = 0 (not quite at r = 0 as RHS of Eq. (6) diverges there). Take this small value of r to be r = δ. Then the mass boundary condition is trivial, m(δ) = 0. This leaves only one non-trivial boundary condition, ρ(δ), i.e., the mass density at the centre of the white dwarf. As a f ...
Exam Study Guide
... 88. If a white dwarf is in a binary, what can happen to it and what does it become? 89. A neutron star is expected to spin rapidly because 90. In a survey of pulsars in binary systems, it is found that none of the pulsars has a mass greater than 3 solar masses. This is because … 91. If the Sun were ...
... 88. If a white dwarf is in a binary, what can happen to it and what does it become? 89. A neutron star is expected to spin rapidly because 90. In a survey of pulsars in binary systems, it is found that none of the pulsars has a mass greater than 3 solar masses. This is because … 91. If the Sun were ...
Sources of energy and the origin of the chemical elements
... mainly of hydrogen and helium, whose mass is too small to ignite stable thermonuclear hydrogen fusion in its interior (but they do produce some helium isotopes by fusing protons with deuterium, lithium and berillium). Theoretical expectations: M < 0.08 M¤. Incapable of generating substantial amount ...
... mainly of hydrogen and helium, whose mass is too small to ignite stable thermonuclear hydrogen fusion in its interior (but they do produce some helium isotopes by fusing protons with deuterium, lithium and berillium). Theoretical expectations: M < 0.08 M¤. Incapable of generating substantial amount ...
Binary Star Par 1802 Word Document
... An unusual binary star system in the Orion nebula (Translated from Sterne und Weltraum 12/08 by G S Kelly) For many years astronomers have assumed that the stars in binary or multiple systems form at the same time. Now, however, a research team headed by Keivan Stassun at the Vanderbilt University i ...
... An unusual binary star system in the Orion nebula (Translated from Sterne und Weltraum 12/08 by G S Kelly) For many years astronomers have assumed that the stars in binary or multiple systems form at the same time. Now, however, a research team headed by Keivan Stassun at the Vanderbilt University i ...
Home | STA Notes
... (The process of change that occurs throughout a star's life is known as stellar evolution.) The reason there are so many stars on the main sequence is that stars spend most of their lives there. They start their lives away from the main sequence, but it only takes a relatively "brief" (in astronomic ...
... (The process of change that occurs throughout a star's life is known as stellar evolution.) The reason there are so many stars on the main sequence is that stars spend most of their lives there. They start their lives away from the main sequence, but it only takes a relatively "brief" (in astronomic ...
HW10Solutions
... The solar wind consists of protons from the Sun moving toward Earth (the wind actually consists of about 95% protons). The number density of protons at a distance from the Sun equal to the orbital radius of Earth is about 7.0 protons per cubic centimeter. Your research team monitors a satellite that ...
... The solar wind consists of protons from the Sun moving toward Earth (the wind actually consists of about 95% protons). The number density of protons at a distance from the Sun equal to the orbital radius of Earth is about 7.0 protons per cubic centimeter. Your research team monitors a satellite that ...
Birth and Death of Stars
... energy to the outer shell of hydrogen which allows fusion to continue. This ongoing fusion radiates energy outward and the outer shell expands and cools creating a red supergiant. ...
... energy to the outer shell of hydrogen which allows fusion to continue. This ongoing fusion radiates energy outward and the outer shell expands and cools creating a red supergiant. ...
Production of Manganese-53 in a Self
... excesses of their daughter isotopes embedded within primitive meteorites found and analyzed via various physical and chemical means over the last 50 years. The challenge is to reconcile the abundances of these short-lived radioactivities, as inferred from meteorites, to those as predicted from ongoi ...
... excesses of their daughter isotopes embedded within primitive meteorites found and analyzed via various physical and chemical means over the last 50 years. The challenge is to reconcile the abundances of these short-lived radioactivities, as inferred from meteorites, to those as predicted from ongoi ...
nuclear reactions in stars: theoretical and experimental
... limited (typically up to a few levels per MeV). When the mass increases the level density is in general too large for cluster models or for an R-matrix approach. In that situation, the cross section essentially depends on properties of the compound nucleus. Here the shell-model approach [?] provides ...
... limited (typically up to a few levels per MeV). When the mass increases the level density is in general too large for cluster models or for an R-matrix approach. In that situation, the cross section essentially depends on properties of the compound nucleus. Here the shell-model approach [?] provides ...
P-nuclei
p-Nuclei (p stands for proton-rich) are certain proton-rich, naturally occurring isotopes of some elements between selenium and mercury which cannot be produced in either s- or r-process.