NUCLEOSYNTHESIS
... Pagel’s book (referred to as Pagel hereafter) covers all the topics in these notes, although it puts more emphasis on galactic chemical evolution and somewhat less on the (stellar) nucleosynthesis processes than we do. A good supplement is the older but still excellent book by Donald Clayton: • D.D. ...
... Pagel’s book (referred to as Pagel hereafter) covers all the topics in these notes, although it puts more emphasis on galactic chemical evolution and somewhat less on the (stellar) nucleosynthesis processes than we do. A good supplement is the older but still excellent book by Donald Clayton: • D.D. ...
Milky Way
... Stellar spectra •Approximate black body spectrum – color tells you temperature •Red is cool, blue is hot •Spectral lines tell you a lot about the star •Different lines for each element (and ionization state) •Strength tells you about composition and temperature ...
... Stellar spectra •Approximate black body spectrum – color tells you temperature •Red is cool, blue is hot •Spectral lines tell you a lot about the star •Different lines for each element (and ionization state) •Strength tells you about composition and temperature ...
BREATHING IN LOW MASS GALAXIES: A STUDY - N
... the fluctuations are strictly periodic, though they would be unlikely to be so in a full cosmological context. The periods of their oscillation are 292, 342, and 387 Myr, respectively. These times are characteristic of the dynamical time of the central region of constant density gas that forms after ...
... the fluctuations are strictly periodic, though they would be unlikely to be so in a full cosmological context. The periods of their oscillation are 292, 342, and 387 Myr, respectively. These times are characteristic of the dynamical time of the central region of constant density gas that forms after ...
Properties of Ellipticals and Spirals
... Velocity dispersions are responsible for the overall shape of galaxies. Oblate and Prolate Ellipticals – how that? Spiral: Velocities of stars in spirals are more ordered. Stars rotate around the galactic center in a disk surrounding it – Halo is random. Spiral galaxies are flattened by rotation (el ...
... Velocity dispersions are responsible for the overall shape of galaxies. Oblate and Prolate Ellipticals – how that? Spiral: Velocities of stars in spirals are more ordered. Stars rotate around the galactic center in a disk surrounding it – Halo is random. Spiral galaxies are flattened by rotation (el ...
P1a_Revision_lesson
... as a fuel. During its main sequence a star will release energy by combining hydrogen and helium nuclei (light elements) into _________ elements. Any element in space that is heavier than helium is thought to have been made in a star. Words – heavier, balanced, hydrogen, nuclear, temperatures ...
... as a fuel. During its main sequence a star will release energy by combining hydrogen and helium nuclei (light elements) into _________ elements. Any element in space that is heavier than helium is thought to have been made in a star. Words – heavier, balanced, hydrogen, nuclear, temperatures ...
Educational Brief
... centimeter) - this is much less dense than the ISM surrounding it. The coffee mug that would contain about 500 hydrogen atoms in the average ISM would only contain 1 hydrogen atom (or maybe none at all!) if it were in the Local Bubble. This gas is also extremely hot—about 1 million degrees Kelvin (1 ...
... centimeter) - this is much less dense than the ISM surrounding it. The coffee mug that would contain about 500 hydrogen atoms in the average ISM would only contain 1 hydrogen atom (or maybe none at all!) if it were in the Local Bubble. This gas is also extremely hot—about 1 million degrees Kelvin (1 ...
our knowledge of high-mass star formation at the dawn of - CEA-Irfu
... high-mass star formation have been called massive starless or pre-stellar cores, massive cold molecular cores, or even infrared-dark clouds. In the subsequent phase, they have been named massive protostars, high-mass protostellar objects, or hot molecular cores. The better-known final phase would co ...
... high-mass star formation have been called massive starless or pre-stellar cores, massive cold molecular cores, or even infrared-dark clouds. In the subsequent phase, they have been named massive protostars, high-mass protostellar objects, or hot molecular cores. The better-known final phase would co ...
L69 CONVERSION OF NEUTRON STARS TO
... for nonrotating compact objects (Oppenheimer & Volkoff 1939). To highlight the dependence of E conv on the present uncertainties in the microphysics, we employed different models for the EOS of both NSM and SQM. Recently, a microscopic EOS of dense stellar matter has been calculated by Baldo, Bombac ...
... for nonrotating compact objects (Oppenheimer & Volkoff 1939). To highlight the dependence of E conv on the present uncertainties in the microphysics, we employed different models for the EOS of both NSM and SQM. Recently, a microscopic EOS of dense stellar matter has been calculated by Baldo, Bombac ...
The coronal temperatures of low-mass main
... the relevant parameter, then this would indicate that temperature scales somehow with how far a star is below the saturation threshold in rotation, given that saturation happens at a single mass-independent value of RX . It would further imply that all saturated stars have similar coronal temperatur ...
... the relevant parameter, then this would indicate that temperature scales somehow with how far a star is below the saturation threshold in rotation, given that saturation happens at a single mass-independent value of RX . It would further imply that all saturated stars have similar coronal temperatur ...
Nuclear Astrophysics
... • Shell outside core burning CNO-cycle • Convective outer envelope composed of (original) hydrogen and all other nascent abundances from original gas nebula The temperature is high enough in the CNO shell that the CNO1,2 cycles can, in principle, both function. ...
... • Shell outside core burning CNO-cycle • Convective outer envelope composed of (original) hydrogen and all other nascent abundances from original gas nebula The temperature is high enough in the CNO shell that the CNO1,2 cycles can, in principle, both function. ...
SGHS Faulkes ASISTM Star Cluster Photometry
... plot your graph. h) Now open the Excel file “SGHS Faulkes Star Cluster Photometry.xlsx” in I:\SCIENCE faculty\Mr Stanger\astronomy club\SGHS Faulkes Telescope Documents\ and go and measure B and V values for as many stars as possible in the cluster from images M80-B.fits and M80-V.fits. Remember to ...
... plot your graph. h) Now open the Excel file “SGHS Faulkes Star Cluster Photometry.xlsx” in I:\SCIENCE faculty\Mr Stanger\astronomy club\SGHS Faulkes Telescope Documents\ and go and measure B and V values for as many stars as possible in the cluster from images M80-B.fits and M80-V.fits. Remember to ...
Star Formation in Bok Globules - European Southern Observatory
... can provide much valuable information; but with the advent of molecular radio astronomy it has now become possible to obtain precise data on masses, temperatures and composition of the globules. Typical globule masses are between 15 M0 and 60 M0 , and temperatures are around 10 K to 20 K. The interi ...
... can provide much valuable information; but with the advent of molecular radio astronomy it has now become possible to obtain precise data on masses, temperatures and composition of the globules. Typical globule masses are between 15 M0 and 60 M0 , and temperatures are around 10 K to 20 K. The interi ...
Chapter 17
... begins to contract under its own gravitational force; as it collapses, the center becomes hotter and hotter until nuclear fusion begins in the core. When looking at just a few atoms, the gravitational force is nowhere near strong enough to overcome the random thermal motion. Even a massive cloud of ...
... begins to contract under its own gravitational force; as it collapses, the center becomes hotter and hotter until nuclear fusion begins in the core. When looking at just a few atoms, the gravitational force is nowhere near strong enough to overcome the random thermal motion. Even a massive cloud of ...
FutureEnvironments
... are the hottest, largest, and brightest stars, and class M stars as the smallest and coldest, with a gradual scale between them. Since a star’s mass determines how hot it burns (as well as how strong its gravity pull is), the star’s classification actually helps extrapolate the kinds of planets that ...
... are the hottest, largest, and brightest stars, and class M stars as the smallest and coldest, with a gradual scale between them. Since a star’s mass determines how hot it burns (as well as how strong its gravity pull is), the star’s classification actually helps extrapolate the kinds of planets that ...
poster
... White lines mark out two cores that we identify with a minimum spanning tree (MST) analysis. The dashed white line shows a suggestive way to separate the western core into two parts (North: low stellar density and South: high stellar density). ...
... White lines mark out two cores that we identify with a minimum spanning tree (MST) analysis. The dashed white line shows a suggestive way to separate the western core into two parts (North: low stellar density and South: high stellar density). ...
Lesson 6 - Magnitudes of Stars
... We’d really like to know things that are intrinsic properties of the star like: Luminosity (energy output) and Temperature ...
... We’d really like to know things that are intrinsic properties of the star like: Luminosity (energy output) and Temperature ...
Stellar evolution
Stellar evolution is the process by which a star changes during its lifetime. Depending on the mass of the star, this lifetime ranges from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. The table shows the lifetimes of stars as a function of their masses. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star.Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase. Stars with at least half the mass of the Sun can also begin to generate energy through the fusion of helium at their core, whereas more-massive stars can fuse heavier elements along a series of concentric shells. Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula. Stars with around ten or more times the mass of the Sun can explode in a supernova as their inert iron cores collapse into an extremely dense neutron star or black hole. Although the universe is not old enough for any of the smallest red dwarfs to have reached the end of their lives, stellar models suggest they will slowly become brighter and hotter before running out of hydrogen fuel and becoming low-mass white dwarfs.Stellar evolution is not studied by observing the life of a single star, as most stellar changes occur too slowly to be detected, even over many centuries. Instead, astrophysicists come to understand how stars evolve by observing numerous stars at various points in their lifetime, and by simulating stellar structure using computer models.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.