![Lecture 15.Dark.Matter.Dark.Energy [Autosaved]](http://s1.studyres.com/store/data/001653481_1-24d181abb7aa2350426c5e71bf17efb8-300x300.png)
Lecture 15.Dark.Matter.Dark.Energy [Autosaved]
... Future for dark matter detection “… what we are witnessing is an example of how the identification of dark matter will come about. We cannot expect a claim, beyond any statistical or systematic doubt, from a single experiment, but rather a gradual process. At some point there will be a barely signi ...
... Future for dark matter detection “… what we are witnessing is an example of how the identification of dark matter will come about. We cannot expect a claim, beyond any statistical or systematic doubt, from a single experiment, but rather a gradual process. At some point there will be a barely signi ...
Galaxies
... • The stars in the spiral arms are mainly metal-rich population I star • Sub-classification based on the smoothness of spiral arms and size of bulge: Sa, Sb, Sc – Sa: broad arms, relatively large bulge ...
... • The stars in the spiral arms are mainly metal-rich population I star • Sub-classification based on the smoothness of spiral arms and size of bulge: Sa, Sb, Sc – Sa: broad arms, relatively large bulge ...
Dark matter
... Only 20% of the dark matter is MACHOs: Some of the dark matter in galaxy “halos” consists of exotic matter. Suppose there existed a type of massive elementary particle that didn’t absorb, emit, or scatter photons. We’d detect such a particle only by its gravitational pull on luminous matter. ...
... Only 20% of the dark matter is MACHOs: Some of the dark matter in galaxy “halos” consists of exotic matter. Suppose there existed a type of massive elementary particle that didn’t absorb, emit, or scatter photons. We’d detect such a particle only by its gravitational pull on luminous matter. ...
thumbnail images - Kapteyn Astronomical Institute
... 1. When did the first objects form? 2. What are the progenitors of present-day giant ellipticals? 3. What types of galaxies are there at z> 1, 2, 4? 4. How many massive galaxies were already assembled at z=1,2,4? 5. How does the star formation and galaxy stellar mass density evolve? 6. What is the e ...
... 1. When did the first objects form? 2. What are the progenitors of present-day giant ellipticals? 3. What types of galaxies are there at z> 1, 2, 4? 4. How many massive galaxies were already assembled at z=1,2,4? 5. How does the star formation and galaxy stellar mass density evolve? 6. What is the e ...
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.