Dark Matter Concept Questions
... 6. Do your results support the following statement? “It is reasonable to expect that stars orbit around the gravitational mass contained within the radius of their orbit in the same way that planets orbit around the Sun.” Discuss. 7. Explain the shape of your plot for measured speed against orbital ...
... 6. Do your results support the following statement? “It is reasonable to expect that stars orbit around the gravitational mass contained within the radius of their orbit in the same way that planets orbit around the Sun.” Discuss. 7. Explain the shape of your plot for measured speed against orbital ...
Dark Matter - the stuff of the Universe?
... Microlensing: light (from star in Large Magellanic Cloud) bending round unseen object (in halo of our Galaxy) ...
... Microlensing: light (from star in Large Magellanic Cloud) bending round unseen object (in halo of our Galaxy) ...
PH109 Exploring the Universe, Test#4, Spring 2005 Please indicate
... b) is best detected from the x-rays it produces in the intergalactic medium. c) will have no effect on the fate of the universe. d) comprises over 90% of the entire mass of the universe. 30. Which of these astronomers first related speeds and distances for galaxies? a) Harlow Shapley , b) Edwin Hubb ...
... b) is best detected from the x-rays it produces in the intergalactic medium. c) will have no effect on the fate of the universe. d) comprises over 90% of the entire mass of the universe. 30. Which of these astronomers first related speeds and distances for galaxies? a) Harlow Shapley , b) Edwin Hubb ...
r - JILA
... Motions of the stars and gas in the disk of a spiral galaxy are approximately circular (vR and vz << vf). Define the circular velocity at radius r in the galaxy as V(r). Acceleration of the star moving in a circular orbit must be provided by a net inward gravitational acceleration: ...
... Motions of the stars and gas in the disk of a spiral galaxy are approximately circular (vR and vz << vf). Define the circular velocity at radius r in the galaxy as V(r). Acceleration of the star moving in a circular orbit must be provided by a net inward gravitational acceleration: ...
Lecture 12: Age, Metalicity, and Observations Abundance
... that seem to determine observed metallicity are mass and SFR. • This forms the fundamental metallicity relation (FMR). • Despite extremely complex underlying physics, the relation exists out to z=2.5 and in a huge range of galaxies/ environments. ...
... that seem to determine observed metallicity are mass and SFR. • This forms the fundamental metallicity relation (FMR). • Despite extremely complex underlying physics, the relation exists out to z=2.5 and in a huge range of galaxies/ environments. ...
Question 1
... the source of energy is very small. energy is coming from matter and antimatter. the energy source is rotating rapidly. a chain reaction of supernovas occurs. there are many separate sources of energy in the core. ...
... the source of energy is very small. energy is coming from matter and antimatter. the energy source is rotating rapidly. a chain reaction of supernovas occurs. there are many separate sources of energy in the core. ...
Stellar Mass Assembly History
... Cimatti et al. 2006 and Brown et al. 2006 emphasize that, if only a factor of two in mass is added to the red sequence since z~1, and it is mainly in lower luminosity (< 1011Msun) galaxies, then simple “running down” of star formation in disk galaxies, turning them red, can account for the growth. ...
... Cimatti et al. 2006 and Brown et al. 2006 emphasize that, if only a factor of two in mass is added to the red sequence since z~1, and it is mainly in lower luminosity (< 1011Msun) galaxies, then simple “running down” of star formation in disk galaxies, turning them red, can account for the growth. ...
Slide 1
... What is the intermediate phase-mixing state as a star-forming region evaporates into a dIrr/dSph environ (theory/obs) Are there many small DM sub-halos in mid-sized dIrr galaxies (LMC-like) – look for effect on HI/GMC. Whatever caused the pre-enrichment*, might this (set of) processes affect early s ...
... What is the intermediate phase-mixing state as a star-forming region evaporates into a dIrr/dSph environ (theory/obs) Are there many small DM sub-halos in mid-sized dIrr galaxies (LMC-like) – look for effect on HI/GMC. Whatever caused the pre-enrichment*, might this (set of) processes affect early s ...
Lecture 33
... • It was all over in less than an hour, as T dropped from 3 billion to <300 million degrees • It stopped essentially because all the neutrons got used up, essentially all moving into helium-4 nuclei • A tiny amount of Li and Be were created too...nothing heavier ...
... • It was all over in less than an hour, as T dropped from 3 billion to <300 million degrees • It stopped essentially because all the neutrons got used up, essentially all moving into helium-4 nuclei • A tiny amount of Li and Be were created too...nothing heavier ...
Weak gravitational lensing
While the presence of any mass bends the path of light passing near it, this effect rarely produces the giant arcs and multiple images associated with strong gravitational lensing. Most lines of sight in the universe are thoroughly in the weak lensing regime, in which the deflection is impossible to detect in a single background source. However, even in these cases, the presence of the foreground mass can be detected, by way of a systematic alignment of background sources around the lensing mass. Weak gravitational lensing is thus an intrinsically statistical measurement, but it provides a way to measure the masses of astronomical objects without requiring assumptions about their composition or dynamical state.