Lecture 16: Iron Core Collapse, Neutron Stars, and Nucleosynthesis
... All of the elements made by nuclear reactions during the star’s life are ejected, along with some new ones made during the explosion. Some of these, like 56Ni, are radioactive and will play a role in powering the light curve ...
... All of the elements made by nuclear reactions during the star’s life are ejected, along with some new ones made during the explosion. Some of these, like 56Ni, are radioactive and will play a role in powering the light curve ...
Abstract Submitted for the PHY599 Meeting of
... age is that it allows the study of the time evolution of astronomical phenomena related to stars and their surrounding bodies. I will start with a basic and short description of the Hertzsprung-Russell-Diagram, which allows (together with stellar evolutionary models) an age determination for star cl ...
... age is that it allows the study of the time evolution of astronomical phenomena related to stars and their surrounding bodies. I will start with a basic and short description of the Hertzsprung-Russell-Diagram, which allows (together with stellar evolutionary models) an age determination for star cl ...
Supernovas 10/19
... All elements heavier than Helium are made inside stars up to Iron - fusion in Red Giants heavier than Iron (and some lighter) - Supernova explosions • Stars lose matter at end of life-cycle becoming Red Giants (can detect) Supernova debris (can detect) and this matter forms new stars (and planets an ...
... All elements heavier than Helium are made inside stars up to Iron - fusion in Red Giants heavier than Iron (and some lighter) - Supernova explosions • Stars lose matter at end of life-cycle becoming Red Giants (can detect) Supernova debris (can detect) and this matter forms new stars (and planets an ...
An Introduction - Solar Physics and Space Weather
... enough to pass the deuterium (2H, one proton + one neutron) bottleneck to further produce helium •At 15 minutes, the temperature of the universe is too low for any further nucleosynthesis •Therefore, the relics of primordial fireball are hydrogen, helium (1 helium out of every 10 protons), and photo ...
... enough to pass the deuterium (2H, one proton + one neutron) bottleneck to further produce helium •At 15 minutes, the temperature of the universe is too low for any further nucleosynthesis •Therefore, the relics of primordial fireball are hydrogen, helium (1 helium out of every 10 protons), and photo ...
lecture 27 nuclar fusion in stars
... If the mass is much more than 100 times the sun’s mass, it will blow apart very quickly. In between, a star’s life cycle is determined primarily by its mass. ¤ Stars ...
... If the mass is much more than 100 times the sun’s mass, it will blow apart very quickly. In between, a star’s life cycle is determined primarily by its mass. ¤ Stars ...
More stellar evolution…bloated stars and compact cores
... properties as described (we’re not making this up) • We know the mass of ...
... properties as described (we’re not making this up) • We know the mass of ...
Key Topics Astronomy Unit
... begin nuclear fusion, which converts matter to energy and fuse lighter elements into heavier ones. • All of the elements, except for hydrogen and helium, originated from the nuclear fusion reactions of stars. ...
... begin nuclear fusion, which converts matter to energy and fuse lighter elements into heavier ones. • All of the elements, except for hydrogen and helium, originated from the nuclear fusion reactions of stars. ...
MATTER AND ATOMS
... Sound waves reflect back from objects in front of you Easy to detect a wall this way Impossible to detect a fly this way Size of detectable objects depends on wavelength of sound ...
... Sound waves reflect back from objects in front of you Easy to detect a wall this way Impossible to detect a fly this way Size of detectable objects depends on wavelength of sound ...
Evolution of High Mass Stars
... Higher T ⇒ more nuclear burning stages (it is the high mass stars that make the elements heavier than C,N,O and even most of the C,N,O that goes into the ISM. ...
... Higher T ⇒ more nuclear burning stages (it is the high mass stars that make the elements heavier than C,N,O and even most of the C,N,O that goes into the ISM. ...
Atoms and Elements
... two atoms across) near the surface of a sample, and applying a voltage. – A small electric current flows from the sample to the probe in a process called electron tunneling. – The strength of the current flow is sensitive to the distance between the sample and the probe. – By adjusting the distance ...
... two atoms across) near the surface of a sample, and applying a voltage. – A small electric current flows from the sample to the probe in a process called electron tunneling. – The strength of the current flow is sensitive to the distance between the sample and the probe. – By adjusting the distance ...
Linking Asteroids and Meteorites through Reflectance Spectroscopy
... • The temperatures of high-mass stars in its latestage of life can reach temperatures above 600 million Kelvin • Can fuse Carbon and heavier elements • Helium Capture can also occur where Helium can be fused into heavy elements ...
... • The temperatures of high-mass stars in its latestage of life can reach temperatures above 600 million Kelvin • Can fuse Carbon and heavier elements • Helium Capture can also occur where Helium can be fused into heavy elements ...
26.5 Guided Notes
... The American astronomer Edwin Hubble observed a red shift in the light spectra of galaxies which shows that the universe is expanding. A blue shift would indicate that the universe was condensing. ...
... The American astronomer Edwin Hubble observed a red shift in the light spectra of galaxies which shows that the universe is expanding. A blue shift would indicate that the universe was condensing. ...
Life Cycle of Stars - Lab Science Schedule
... Medium-sized stars pass through a red-giant stage before they become white dwarfs and die. The core of the star left behind after the supernova may become a neutron star or a black hole, depending on the star’s starting mass. The Life and Death of Stars Changes in stars may take place over a few mil ...
... Medium-sized stars pass through a red-giant stage before they become white dwarfs and die. The core of the star left behind after the supernova may become a neutron star or a black hole, depending on the star’s starting mass. The Life and Death of Stars Changes in stars may take place over a few mil ...
2.5.2 development of a star
... During this time it is stable as the gravitational forces that enable hydrogen burning balance and pull the star in, balance with the gas pressure pushing out. This is much like the gas pressure inside a balloon balancing with the tension in the plastic of the balloon. In the star it is known ...
... During this time it is stable as the gravitational forces that enable hydrogen burning balance and pull the star in, balance with the gas pressure pushing out. This is much like the gas pressure inside a balloon balancing with the tension in the plastic of the balloon. In the star it is known ...
CEA - Nuclear astrophysics
... energy particles present in space, occur that transcosmic radiation. This flux makes the heaviest nuclei present in the form atomic interstellar environment (carbon, nuclei in what is nitrogen, etc.) explode, and the nuclei produced (lithium, known as stellar beryllium, boron) are dispersed. nucleos ...
... energy particles present in space, occur that transcosmic radiation. This flux makes the heaviest nuclei present in the form atomic interstellar environment (carbon, nuclei in what is nitrogen, etc.) explode, and the nuclei produced (lithium, known as stellar beryllium, boron) are dispersed. nucleos ...
Gilbert Ch 2 - Santa Rosa Junior College
... • Fusing of fundamental/subatomic particles (protons/neutrons) created atomic nuclei ...
... • Fusing of fundamental/subatomic particles (protons/neutrons) created atomic nuclei ...
7.1 Gravitational Potential Energy
... a peak near Fe (hence the term Fe-peak). Fusion of Fe-peak elements to form elements of higher mass is an endothermic process requiring an additional supply of energy (and conversely, energy can be released by the fission of these heavier nuclei into lighter ones, as in a nuclear power station). The ...
... a peak near Fe (hence the term Fe-peak). Fusion of Fe-peak elements to form elements of higher mass is an endothermic process requiring an additional supply of energy (and conversely, energy can be released by the fission of these heavier nuclei into lighter ones, as in a nuclear power station). The ...
Unit 5 - Stars
... helium. If the temperature gets high enough, the cores of these stars can continue fusion through the triple-alpha process. To model this, take two of your helium nuclei (also called alpha particles) and smash them together. This forms a very unstable beryllium atom. If a third helium nucleus hits i ...
... helium. If the temperature gets high enough, the cores of these stars can continue fusion through the triple-alpha process. To model this, take two of your helium nuclei (also called alpha particles) and smash them together. This forms a very unstable beryllium atom. If a third helium nucleus hits i ...
The Big Bang Theory
... Before the Big Bang, there was no time or space. The Big Bang marked the beginning of the universe's expansion from a single point that was infinitely small, infinitely hot, and infinitely dense. ...
... Before the Big Bang, there was no time or space. The Big Bang marked the beginning of the universe's expansion from a single point that was infinitely small, infinitely hot, and infinitely dense. ...
Beta-delayed two-neutron emission
... experimentally for 9 different nuclei, but only the decay of 31Ar has been studied to some extent. On the neutron-rich side, b-delayed two-neutron emission has been evidenced for 7 nuclei with branching ratios ranging from 1% to 10%. However, for none of these nuclei, correlations between the two ne ...
... experimentally for 9 different nuclei, but only the decay of 31Ar has been studied to some extent. On the neutron-rich side, b-delayed two-neutron emission has been evidenced for 7 nuclei with branching ratios ranging from 1% to 10%. However, for none of these nuclei, correlations between the two ne ...
The Luna experiment - EPJ Web of Conferences
... Two electrostatic accelerators able to deliver hydrogen or helium beams have been installed in LUNA: first a compact 50 kV home made machine and then, in the year 2000, a commercial 400 kV one. Common features of the two accelerators are the high beam current, the long term stability and the precise ...
... Two electrostatic accelerators able to deliver hydrogen or helium beams have been installed in LUNA: first a compact 50 kV home made machine and then, in the year 2000, a commercial 400 kV one. Common features of the two accelerators are the high beam current, the long term stability and the precise ...
glossary - Discovery Education
... of neutrons, or the remains of a supernova explosion. nova — a stellar explosion of a red giant star, ending in a planetary nebula and a white dwarf. parsec — a distance of 3.26 light-years; used to measure immense distances in space. planetary nebula — a ring of dust and gas blown off a red giant s ...
... of neutrons, or the remains of a supernova explosion. nova — a stellar explosion of a red giant star, ending in a planetary nebula and a white dwarf. parsec — a distance of 3.26 light-years; used to measure immense distances in space. planetary nebula — a ring of dust and gas blown off a red giant s ...
Life of a star
... In stars with masses comparable to the sun, the nucleus stops collapsing only when the inner temperature reaches above 100 million degrees, the threshold temperature necessary to start up nuclear fusions again. This time helium atoms fuse with carbon atoms releasing the necessary energy to regain th ...
... In stars with masses comparable to the sun, the nucleus stops collapsing only when the inner temperature reaches above 100 million degrees, the threshold temperature necessary to start up nuclear fusions again. This time helium atoms fuse with carbon atoms releasing the necessary energy to regain th ...
Nucleosynthesis
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons. The first nuclei were formed about three minutes after the Big Bang, through the process called Big Bang nucleosynthesis. It was then that hydrogen and helium formed to become the content of the first stars, and this primeval process is responsible for the present hydrogen/helium ratio of the cosmos.With the formation of stars, heavier nuclei were created from hydrogen and helium by stellar nucleosynthesis, a process that continues today. Some of these elements, particularly those lighter than iron, continue to be delivered to the interstellar medium when low mass stars eject their outer envelope before they collapse to form white dwarfs. The remains of their ejected mass form the planetary nebulae observable throughout our galaxy.Supernova nucleosynthesis within exploding stars by fusing carbon and oxygen is responsible for the abundances of elements between magnesium (atomic number 12) and nickel (atomic number 28). Supernova nucleosynthesis is also thought to be responsible for the creation of rarer elements heavier than iron and nickel, in the last few seconds of a type II supernova event. The synthesis of these heavier elements absorbs energy (endothermic) as they are created, from the energy produced during the supernova explosion. Some of those elements are created from the absorption of multiple neutrons (the R process) in the period of a few seconds during the explosion. The elements formed in supernovas include the heaviest elements known, such as the long-lived elements uranium and thorium.Cosmic ray spallation, caused when cosmic rays impact the interstellar medium and fragment larger atomic species, is a significant source of the lighter nuclei, particularly 3He, 9Be and 10,11B, that are not created by stellar nucleosynthesis.In addition to the fusion processes responsible for the growing abundances of elements in the universe, a few minor natural processes continue to produce very small numbers of new nuclides on Earth. These nuclides contribute little to their abundances, but may account for the presence of specific new nuclei. These nuclides are produced via radiogenesis (decay) of long-lived, heavy, primordial radionuclides such as uranium and thorium. Cosmic ray bombardment of elements on Earth also contribute to the presence of rare, short-lived atomic species called cosmogenic nuclides.