Notes - Michigan State University
... then He core grows by H-shell burning until He-burning sets in. He burning is initially unstable (He flash) in degenerate electron gas, pressure does not depend on temperature (why ?) therefore a slight rise in temperature is not compensated by expansion ...
... then He core grows by H-shell burning until He-burning sets in. He burning is initially unstable (He flash) in degenerate electron gas, pressure does not depend on temperature (why ?) therefore a slight rise in temperature is not compensated by expansion ...
5. Lectures on Spectroscopy and Atomic Physics.
... 1. Deuterium is a form of hydrogen that has a nucleus of one proton (that’s why it’s still hydrogen) plus one neutron. 2. Tritium is another form of hydrogen with one proton and two neutrons in the nucleus. ...
... 1. Deuterium is a form of hydrogen that has a nucleus of one proton (that’s why it’s still hydrogen) plus one neutron. 2. Tritium is another form of hydrogen with one proton and two neutrons in the nucleus. ...
Where Did All The Elements Come From??
... supergiant stars. As the core of the supergiant becomes saturated with iron, its pressure and temperature increase. Eventually, the blackbody radiation from the core produces gamma rays powerful enough to break apart the iron atoms in the core. This further increases the pressure to a point where el ...
... supergiant stars. As the core of the supergiant becomes saturated with iron, its pressure and temperature increase. Eventually, the blackbody radiation from the core produces gamma rays powerful enough to break apart the iron atoms in the core. This further increases the pressure to a point where el ...
The big bang left the universe with its first atoms
... supergiant stars. As the core of the supergiant becomes saturated with iron, its pressure and temperature increase. Eventually, the blackbody radiation from the core produces gamma rays powerful enough to break apart the iron atoms in the core. This further increases the pressure to a point where el ...
... supergiant stars. As the core of the supergiant becomes saturated with iron, its pressure and temperature increase. Eventually, the blackbody radiation from the core produces gamma rays powerful enough to break apart the iron atoms in the core. This further increases the pressure to a point where el ...
Astronomy 112: The Physics of Stars Class 8 Notes: Nuclear
... the p − p chain, for proton proton chain. It is not surprising that the reaction involves protons, i.e. hydrogen nuclei. These are by far the most abundance nuclei in main sequence stars, and, since the strength of the Coulomb barrier scales as Zi Zj , it is also the reaction with the lowest Coulomb ...
... the p − p chain, for proton proton chain. It is not surprising that the reaction involves protons, i.e. hydrogen nuclei. These are by far the most abundance nuclei in main sequence stars, and, since the strength of the Coulomb barrier scales as Zi Zj , it is also the reaction with the lowest Coulomb ...
Scientific Background Paper: Iron`s Place and Role
... The stages of stellar evolution are determined by the mechanism used to limit the collapse of a star by producing an outward force to overcome the inward pull of gravity. The lifecycle of stars begins with the in-fall of a ball of gas and dust and their death is ultimately the failure to find a mech ...
... The stages of stellar evolution are determined by the mechanism used to limit the collapse of a star by producing an outward force to overcome the inward pull of gravity. The lifecycle of stars begins with the in-fall of a ball of gas and dust and their death is ultimately the failure to find a mech ...
Слайд 1 - University of Wrocław
... 2. The neutron star matter is so dense that P is almost independen t of the temperatu re T and is determined by the mass density and the compositio n of the matter; one usually w rites P P ( ). 3. The mass density is defined as E / c 2 , where E [erg/cc] is the total energy density (includ ...
... 2. The neutron star matter is so dense that P is almost independen t of the temperatu re T and is determined by the mass density and the compositio n of the matter; one usually w rites P P ( ). 3. The mass density is defined as E / c 2 , where E [erg/cc] is the total energy density (includ ...
catch some rays: alpha, beta, gamma (modified for adeed)
... gamma (γ) ray - a ray that is like an X-ray but of higher energy and that is given off especially by a radioactive substance PET scan – a three-dimensional image or map of functional processes in the body completed with positron emission tomography (PET), a nuclear medicine imaging technique radioac ...
... gamma (γ) ray - a ray that is like an X-ray but of higher energy and that is given off especially by a radioactive substance PET scan – a three-dimensional image or map of functional processes in the body completed with positron emission tomography (PET), a nuclear medicine imaging technique radioac ...
Dwarf novae
... If the second star is not a compact object and is close enough, it will transfer mass onto the white dwarf ...
... If the second star is not a compact object and is close enough, it will transfer mass onto the white dwarf ...
PowerPoint
... we add more protons the Coulomb repulsion between protons diminishes the binding of heavier nuclei. In nuclei past Pb (lead) the large Coulomb energy makes the nuclei prone to fission. After Thorium nuclei are not stable anymore. ...
... we add more protons the Coulomb repulsion between protons diminishes the binding of heavier nuclei. In nuclei past Pb (lead) the large Coulomb energy makes the nuclei prone to fission. After Thorium nuclei are not stable anymore. ...
Evolution and the Big Bang, ET Life Lec. 6, Jan 18, 2002
... Nuclei are made of protons and neutrons. These particles have similar mass but only protons have an electric charge. Protons and neutrons are each made of three quarks. By about 3 min. after Big Bang all of the neutrons are bound into 4He nuclei which have two protons (Helium has Z=2) and 2 neutrons ...
... Nuclei are made of protons and neutrons. These particles have similar mass but only protons have an electric charge. Protons and neutrons are each made of three quarks. By about 3 min. after Big Bang all of the neutrons are bound into 4He nuclei which have two protons (Helium has Z=2) and 2 neutrons ...
Chapter 13 Practice Questions
... A) mainly carbon and oxygen nuclei supported by electron degeneracy pressure in a volume about the size of the Sun. B) mostly hydrogen nuclei supported by normal gas pressure due to the very high gas temperature, in a volume about the size of the Earth. C) mainly carbon and oxygen nuclei supported b ...
... A) mainly carbon and oxygen nuclei supported by electron degeneracy pressure in a volume about the size of the Sun. B) mostly hydrogen nuclei supported by normal gas pressure due to the very high gas temperature, in a volume about the size of the Earth. C) mainly carbon and oxygen nuclei supported b ...
Widener University Summer 2004 ENVR 261 Modern Physics Name
... Consider a square well with one finite wall and one infinite wall. Compare the energy and momentum of a particle trapped in this well to the energy and momentum of an identical particle trapped in an infinite well with the same width. ...
... Consider a square well with one finite wall and one infinite wall. Compare the energy and momentum of a particle trapped in this well to the energy and momentum of an identical particle trapped in an infinite well with the same width. ...
The Nuclear Fusion Reaction Inside Stars
... How is helium created? With your group discuss how nuclear fusion might happen to create helium. Diagram on dry erase board how helium is made in a star Be ready to present your idea to the class. ...
... How is helium created? With your group discuss how nuclear fusion might happen to create helium. Diagram on dry erase board how helium is made in a star Be ready to present your idea to the class. ...
Nuclear drip line
In nuclear physics, the boundaries for nuclear particle-stability are called drip lines. Atomic nuclei contain both protons and neutrons—the number of protons defines the identity of that element (ie, carbon always has 6 protons), but the number of neutrons within that element may vary (carbon-12 and its isotope carbon-13, for example). The number of isotopes each element may have is visually represented by plotting boxes, each of which represents a unique nuclear species, on a graph with the number of neutrons increasing on the abscissa (X axis) and number of protons increasing along the ordinate (Y axis). The resulting chart is commonly referred to as the table of nuclides, and is to nuclear physics what the periodic table of the elements is to chemistry.An arbitrary combination of protons and neutrons does not necessarily yield a stable nucleus. One can think of moving up and/or to the right across the nuclear chart by adding one type of nucleon (i.e. a proton or neutron, both called nucleons) to a given nucleus. However, adding nucleons one at a time to a given nucleus will eventually lead to a newly formed nucleus that immediately decays by emitting a proton (or neutron). Colloquially speaking, the nucleon has 'leaked' or 'dripped' out of the nucleus, hence giving rise to the term ""drip line"". Drip lines are defined for protons, neutrons, and alpha particles, and these all play important roles in nuclear physics. The nucleon drip lines are at the extreme of the proton-to-neutron ratio: at p:n ratios at or beyond the driplines, no stable nuclei can exist. The location of the neutron drip line is not well known for most of the nuclear chart, whereas the proton and alpha driplines have been measured for a wide range of elements. The nucleons drip out of such unstable nuclei for the same reason that water drips from a leaking faucet: in the water case, there is a lower potential available that is great enough to overcome surface tension and so produces a droplet; in the case of nuclei, the emission of a particle from a nucleus, against the strong nuclear force, leaves the total potential of the nucleus and the emitted particle in a lower state. Because nucleons are quantized, only integer values are plotted on the table of isotopes; this indicates that the drip line is not linear but instead looks like a step function up close.