Galaxies and Dark Matter
... 3. Which galaxy is closest to earth? How far away is it? How many stars are in it? ________________________________________________________________________ ________________________________________________________________________ _______________________________________________________________________ ...
... 3. Which galaxy is closest to earth? How far away is it? How many stars are in it? ________________________________________________________________________ ________________________________________________________________________ _______________________________________________________________________ ...
Final for Astro 322, Prof. Heinke, April 23rd, 2010 Formula sheet
... d) Which of these features in elliptical galaxies indicate a recent merger? Explain for each feature, why it does or does not. i) Strong absorption lines of H. ii) Strong rotation. iii) “Disky” isophotes. iv) Spherical shells of stars. Problem 5: AGN & Clusters a) A distant quasar is observed to be ...
... d) Which of these features in elliptical galaxies indicate a recent merger? Explain for each feature, why it does or does not. i) Strong absorption lines of H. ii) Strong rotation. iii) “Disky” isophotes. iv) Spherical shells of stars. Problem 5: AGN & Clusters a) A distant quasar is observed to be ...
dm - The Institute of Mathematical Sciences
... decrease as their distance from the centre increased. Instead they orbited roughly at the same speed. What could cause such an effect? There is Dark Matter Consider stars near the centre of a galaxy. As you go further away from the centre (but remain within the bulge), there are more and more stars ...
... decrease as their distance from the centre increased. Instead they orbited roughly at the same speed. What could cause such an effect? There is Dark Matter Consider stars near the centre of a galaxy. As you go further away from the centre (but remain within the bulge), there are more and more stars ...
PowerPoint Presentation - Berkeley Center for Cosmological Physics
... sqrt{F} to try to localize w(zi). Unlike for LSS, for dark energy they do not localize well, and confuse interpretation. Also depends strongly on assumption of w(z>zmax) ...
... sqrt{F} to try to localize w(zi). Unlike for LSS, for dark energy they do not localize well, and confuse interpretation. Also depends strongly on assumption of w(z>zmax) ...
WIMPs vs. MACHOS: What's the Matter?
... million stars This significantly exceeds the single event expected from “known” stars in the Galaxy ...
... million stars This significantly exceeds the single event expected from “known” stars in the Galaxy ...
Discovering Poor Groups with Strong Lensing
... Astrophysics • We only see clumps if they contain stars and/or gas. • Maybe astrophysical processes suppress star formation in small objects, so most clumps are invisible. ...
... Astrophysics • We only see clumps if they contain stars and/or gas. • Maybe astrophysical processes suppress star formation in small objects, so most clumps are invisible. ...
What could it be?: the nature of dark matter
... as radius increases •The result should be a decreasing rotation velocity with increasing radius, ...
... as radius increases •The result should be a decreasing rotation velocity with increasing radius, ...
The Cosmic Dawn : Physics of the First Luminous Objects
... According to the modern theory of cosmological structure formation, the hierarchical assembly of dark matter (DM) halos provided the gravitational potential wells that allowed gas to form stars and galaxies inside them. Modern large telescopes have pushed the detection of galaxies up to a redshift o ...
... According to the modern theory of cosmological structure formation, the hierarchical assembly of dark matter (DM) halos provided the gravitational potential wells that allowed gas to form stars and galaxies inside them. Modern large telescopes have pushed the detection of galaxies up to a redshift o ...
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.