5. cosmic distance ladder ii: standard candles
... dwarf, increasing its mass until it begins to collapse under its own weight. As the white dwarf collapses, it heats up, until it reaches 6 × 108 K, the temperature at which carbon fusion occurs. Since white dwarfs are primarily made of carbon, the entire star ignites and explodes, resulting in what ...
... dwarf, increasing its mass until it begins to collapse under its own weight. As the white dwarf collapses, it heats up, until it reaches 6 × 108 K, the temperature at which carbon fusion occurs. Since white dwarfs are primarily made of carbon, the entire star ignites and explodes, resulting in what ...
Astrophysics - Part 2
... night sky is a measure of its brightness which depends on the intensity of the light received from the star. Stars were in ancient times divided into six levels of apparent magnitude. The brightest were called FIRST MAGNITUDE stars, those just visible to the unaided eye in the darkest sky, SIXTH MAG ...
... night sky is a measure of its brightness which depends on the intensity of the light received from the star. Stars were in ancient times divided into six levels of apparent magnitude. The brightest were called FIRST MAGNITUDE stars, those just visible to the unaided eye in the darkest sky, SIXTH MAG ...
The Cosmic Perspective Star Stuff
... a) Yes, all stars create heavier elements than carbon when they become a supernova. b) Yes, but there would be far fewer heavier elements because highmass stars form elements like iron far more prolifically than low-mass stars. c) No, the core temperatures of low-mass stars are too low to fuse ot ...
... a) Yes, all stars create heavier elements than carbon when they become a supernova. b) Yes, but there would be far fewer heavier elements because highmass stars form elements like iron far more prolifically than low-mass stars. c) No, the core temperatures of low-mass stars are too low to fuse ot ...
What makes stars tick?
... almost everything about the object, from the core temperature, to how long the star lives, to how it dies. While the Sun and a star 10 times its mass may have similarities during the “adult” stages of their lives, they couldn’t be more different as they reach the later stages. Why do some end their ...
... almost everything about the object, from the core temperature, to how long the star lives, to how it dies. While the Sun and a star 10 times its mass may have similarities during the “adult” stages of their lives, they couldn’t be more different as they reach the later stages. Why do some end their ...
X-ray emission from supernova shock waves Tanja Kramer Nymark Department of Astronomy
... in general – it is only about eighty years since astronomers first became aware that some of the “new stars” which occasionally appeared were far too energetic to be understood in the context of what was at the time known about stars. Bright new stars had been seen before, but their nature unfathome ...
... in general – it is only about eighty years since astronomers first became aware that some of the “new stars” which occasionally appeared were far too energetic to be understood in the context of what was at the time known about stars. Bright new stars had been seen before, but their nature unfathome ...
Lecture 15 Star Formation and Evolution 3/7
... Stellar Supernova Explosions For heavy white dwarves with a companion star • acquire mass, if becomes > 1.4 M(Sun) SUPERNOVA (Ia). p + e n + neutrino • Usually leaves neutron star For high mass stars • fusion continues beyond C,O • core of degenerate electrons builds up - opposes gravity • if Mas ...
... Stellar Supernova Explosions For heavy white dwarves with a companion star • acquire mass, if becomes > 1.4 M(Sun) SUPERNOVA (Ia). p + e n + neutrino • Usually leaves neutron star For high mass stars • fusion continues beyond C,O • core of degenerate electrons builds up - opposes gravity • if Mas ...
Stars and Stellar Evolution The Hertzsprung
... the Sun. The diagonal lines correspond to constant stellar radius, so that stellar size can be represented on the same diagram as luminosity and temperature. The first H-R diagrams considered stars in the solar neighbourhood and plotted absolute visual magnitude, M, versus spectral type, which is eq ...
... the Sun. The diagonal lines correspond to constant stellar radius, so that stellar size can be represented on the same diagram as luminosity and temperature. The first H-R diagrams considered stars in the solar neighbourhood and plotted absolute visual magnitude, M, versus spectral type, which is eq ...
Lecture Notes
... dwarf in a binary system. As the mass approaches the ‘Chandrasekhar limit’ of 1.4M , the increasing temperature and density results in ignition of carbon fusion. This proceeds very rapidly, releasing huge amounts of energy in a few seconds. Because all such ‘Type Ia’ supernovae originate in much th ...
... dwarf in a binary system. As the mass approaches the ‘Chandrasekhar limit’ of 1.4M , the increasing temperature and density results in ignition of carbon fusion. This proceeds very rapidly, releasing huge amounts of energy in a few seconds. Because all such ‘Type Ia’ supernovae originate in much th ...
The ultra-luminous x-ray sources near center of M82
... off-nuclear X-ray sources (not at the center) with isotropic luminosities much higher than the Eddington limit for a solar mass black hole (Lx ~ 1.381038 erg/s) Typical X-ray luminosities of ULXs are in between 1039 erg/s and 1041 erg/s (AGN > 1041 erg/s) ...
... off-nuclear X-ray sources (not at the center) with isotropic luminosities much higher than the Eddington limit for a solar mass black hole (Lx ~ 1.381038 erg/s) Typical X-ray luminosities of ULXs are in between 1039 erg/s and 1041 erg/s (AGN > 1041 erg/s) ...
3D GR Hydrodynamic Simulations of Binary Neutron Star
... 1) Capture fluxes on coarse and fine grid AMR boundary 2) Integrate both until coarse and fine grid are aligned in time again 3) Restrict integrated coarse grid flux onto fine grid boundary 4) Difference between integrated coarse grid flux and fine grid flux is correction ...
... 1) Capture fluxes on coarse and fine grid AMR boundary 2) Integrate both until coarse and fine grid are aligned in time again 3) Restrict integrated coarse grid flux onto fine grid boundary 4) Difference between integrated coarse grid flux and fine grid flux is correction ...
http://www.highpoint.edu/~afuller/PHY-1050
... ejects the H and He into space as a planetary nebula. • The core left behind becomes a white dwarf. • Despite the name, this phenomenon has nothing immediate to do with planets ...
... ejects the H and He into space as a planetary nebula. • The core left behind becomes a white dwarf. • Despite the name, this phenomenon has nothing immediate to do with planets ...
Chapter 12
... • How massive are newborn stars? —Stars greater than about 150MSun would be so luminous that radiation pressure would blow them apart. —Degeneracy pressure stops the contraction of objects <0.08MSun before fusion starts. ...
... • How massive are newborn stars? —Stars greater than about 150MSun would be so luminous that radiation pressure would blow them apart. —Degeneracy pressure stops the contraction of objects <0.08MSun before fusion starts. ...
Transcript - Chandra X
... bottom of the scale. The lower left quadrant of the diagram contains hot and dim stars; the upper left quadrant shows hot and bright stars, the upper right quadrant cool and bright, and the lower right quadrant cool and dim. The major branches (locations) of stars are: main sequence, white dwarfs, s ...
... bottom of the scale. The lower left quadrant of the diagram contains hot and dim stars; the upper left quadrant shows hot and bright stars, the upper right quadrant cool and bright, and the lower right quadrant cool and dim. The major branches (locations) of stars are: main sequence, white dwarfs, s ...
Final Stages of Stellar Evolution - supernovae and the synthesis of
... Nucleosynthesis Revision of Nucleosynthesis up to Iron Nuclear Synthesis of Heavy Elements ...
... Nucleosynthesis Revision of Nucleosynthesis up to Iron Nuclear Synthesis of Heavy Elements ...
Article PDF - IOPscience
... the estimated CCSN rate. We therefore conclude that SN 2004ip was very likely a core-collapse event. After correcting for a Galactic extinction of AV p 0.47 (Schlegel et al. 1998), the absolute magnitude of the SN at the time of the discovery becomes MK s p ⫺15.85 (before correcting for the host gal ...
... the estimated CCSN rate. We therefore conclude that SN 2004ip was very likely a core-collapse event. After correcting for a Galactic extinction of AV p 0.47 (Schlegel et al. 1998), the absolute magnitude of the SN at the time of the discovery becomes MK s p ⫺15.85 (before correcting for the host gal ...
Supernovae, Neutrinos, and the Chirality of the Amino Acids
... One suggested mechanism lies with processing of a population of amino acids, or of their chiral precursors, by circularly polarized light [18-23]; this could select one chirality over the other. However, this solution does not easily explain why it would select the same chirality in every situation, ...
... One suggested mechanism lies with processing of a population of amino acids, or of their chiral precursors, by circularly polarized light [18-23]; this could select one chirality over the other. However, this solution does not easily explain why it would select the same chirality in every situation, ...
Astrophysics
... Overview The astrophysics group at North Carolina State University investigates a range of topics within the broad category of high-energy astrophysics. Research includes observations with space-based observatories, analytical and numerical modeling, and large-scale numerical simulations. In additio ...
... Overview The astrophysics group at North Carolina State University investigates a range of topics within the broad category of high-energy astrophysics. Research includes observations with space-based observatories, analytical and numerical modeling, and large-scale numerical simulations. In additio ...
MAIN SEQUENCE STARS, Red Giants and White Dwarfs
... • 16O + 4He 20Ne + • 20Ne + 4He 24Mg + • We’ll come back to this type of onion-layer model star when we talk about supernova explosions and neutron stars. • The elements cooked here are needed for life ...
... • 16O + 4He 20Ne + • 20Ne + 4He 24Mg + • We’ll come back to this type of onion-layer model star when we talk about supernova explosions and neutron stars. • The elements cooked here are needed for life ...
Astro 3303 - Cornell Astronomy
... Distant galaxies • The galaxy ON-108036 • It has a redshift of 7.2. • That redshift corresponds to a “look back time” of 12.9 Gyr, or an epoch of only 749 Myr after the ...
... Distant galaxies • The galaxy ON-108036 • It has a redshift of 7.2. • That redshift corresponds to a “look back time” of 12.9 Gyr, or an epoch of only 749 Myr after the ...
Radiation feedback in star formation simulations
... With Antoine Verliat (masters student this summer with Patrick Hennebelle) Some success explaining expansion of HII regions with constant photon sources (Geen et al 2015a,b, 2016) Can we extend this to explaining the regulation of star formation inside molecular clouds? Fairly easy to get ~1 to 10% ...
... With Antoine Verliat (masters student this summer with Patrick Hennebelle) Some success explaining expansion of HII regions with constant photon sources (Geen et al 2015a,b, 2016) Can we extend this to explaining the regulation of star formation inside molecular clouds? Fairly easy to get ~1 to 10% ...
Lecture12
... Cepheid variable stars are very luminous and can be observed over very large distances. Why are such stars important to astronomers? A. They confirm the theory of nuclear fusion as the energy source for stars. B. They can be used as distance indicators because their luminosity can be determined fro ...
... Cepheid variable stars are very luminous and can be observed over very large distances. Why are such stars important to astronomers? A. They confirm the theory of nuclear fusion as the energy source for stars. B. They can be used as distance indicators because their luminosity can be determined fro ...
The Vampire Stars - d_smith.lhseducators.com
... • As hydrogen from the red giant piles onto the surface of the white dwarf, it may cause the total mass of the white dwarf to surpass the Chandrasekhar Limit. • The electron repulsion can no longer support the star, so the entire star collapses and explodes. ...
... • As hydrogen from the red giant piles onto the surface of the white dwarf, it may cause the total mass of the white dwarf to surpass the Chandrasekhar Limit. • The electron repulsion can no longer support the star, so the entire star collapses and explodes. ...
Which Stars Form Black Holes and Neutron Stars?
... presence of SGR 0525–66 in the metal-poor LMC). If the binary hypothesis is correct, then the extreme mass loss required to turn a >30 M⊙ star into a neutron star should occur infrequently. Alternatively, some process during the supernova, such as a strong magnetically-driven wind [1], might cause t ...
... presence of SGR 0525–66 in the metal-poor LMC). If the binary hypothesis is correct, then the extreme mass loss required to turn a >30 M⊙ star into a neutron star should occur infrequently. Alternatively, some process during the supernova, such as a strong magnetically-driven wind [1], might cause t ...
Sub-luminous type Ia supernovae from the mergers of equal
... diversity. Interestingly, a recent analysis of the spectral evolution of SN 2005bl10, which is representative of the 1991bg-like SNe Ia, showed that both iron group elements and silicon are present over a wide range of radii extending as close to the centre of the ejecta as is accessible observation ...
... diversity. Interestingly, a recent analysis of the spectral evolution of SN 2005bl10, which is representative of the 1991bg-like SNe Ia, showed that both iron group elements and silicon are present over a wide range of radii extending as close to the centre of the ejecta as is accessible observation ...
Supernova
A supernova is a stellar explosion that briefly outshines an entire galaxy, radiating as much energy as the Sun or any ordinary star is expected to emit over its entire life span, before fading from view over several weeks or months. The extremely luminous burst of radiation expels much or all of a star's material at a velocity of up to 7007300000000000000♠30,000 km/s (10% of the speed of light), driving a shock wave into the surrounding interstellar medium. This shock wave sweeps up an expanding shell of gas and dust called a supernova remnant. Supernovae are potentially strong galactic sources of gravitational waves. A great proportion of primary cosmic rays comes from supernovae.Supernovae are more energetic than novae. Nova means ""new"" in Latin, referring to what appears to be a very bright new star shining in the celestial sphere; the prefix ""super-"" distinguishes supernovae from ordinary novae, which are far less luminous. The word supernova was coined by Walter Baade and Fritz Zwicky in 1931. It is pronounced /ˌsuːpərnoʊvə/ with the plural supernovae /ˌsuːpərnoʊviː/ or supernovas (abbreviated SN, plural SNe after ""supernovae"").Supernovae can be triggered in one of two ways: by the sudden re-ignition of nuclear fusion in a degenerate star; or by the gravitational collapse of the core of a massive star. In the first case, a degenerate white dwarf may accumulate sufficient material from a companion, either through accretion or via a merger, to raise its core temperature, ignite carbon fusion, and trigger runaway nuclear fusion, completely disrupting the star. In the second case, the core of a massive star may undergo sudden gravitational collapse, releasing gravitational potential energy that can create a supernova explosion.The most recent directly observed supernova in the Milky Way was Kepler's Star of 1604 (SN 1604); remnants of two more recent supernovae have been found retrospectively. Observations in other galaxies indicate that supernovae should occur on average about three times every century in the Milky Way, and that any galactic supernova would almost certainly be observable in modern astronomical equipment. Supernovae play a significant role in enriching the interstellar medium with higher mass elements. Furthermore, the expanding shock waves from supernova explosions can trigger the formation of new stars.