Astrophysics And Space for dark matter Particles A presentation of dark matter particles, and the searchfor them, by the Particle Astrophysics Group at the University of Sheffield. http://www.hypography.com/links.cfm?query_string=astrophysics and space&startrow
The Search For Dark Matter Particles A presentation of dark matter particles, and the search forthem, by the Particle Astrophysics Group at the University of Sheffield. Particles http://www.hypography.com/info.cfm?id=18075
How Do We Know Dark Matter Exists? that a huge amount of dark (invisible to gravitationally with the normal, visiblematter in the is a service of the High Energy Astrophysics Science Archive http://starchild.gsfc.nasa.gov/docs/StarChild/shadow/questions/question59.html
Extractions: StarChild Question of the Month for July 2003 How do we know dark matter exists? Dark matter is the name scientists have given to the particles which we believe exist in the Universe , but which we cannot directly see! Dark matter was initially called "missing matter" because astronomers could not find it by observing the Universe in any part of the electromagnetic spectrum . This material appears to have mass (and therefore generates gravity ), but it does not appear to absorb or emit any electromagnetic radiation. Given the fact that it does not send us any light (which is how we have learned most of what we know about the Universe), it is not difficult to understand that it has been hard to discover anything about the nature of these mysterious particles. But do not despair, scientists are coming up with clever new ways to probe the dark parts of the cosmos! Scientists study dark matter by looking at the effects it has on visible objects. Scientists believe that dark matter may account for the unexplained motions of stars within galaxies . Computers play an important role in the search for dark matter information. They allow scientists to create models which predict galaxy behavior. Satellites are also being used to gather dark matterinformation. In 1997, a Hubble Space
StarChild: Dark Matter What is the difference between regular matter and dark matter? The StarChild siteis a service of the High Energy Astrophysics Science Archive Research Center http://starchild.gsfc.nasa.gov/docs/StarChild/universe_level1/darkmatter.html
Extractions: Dark Matter Dark matter was once called "missing matter". It was called this because scientists looking at the sky could not find it. Matter is anything that takes up space and has mass . We are used to matter which we will call visible matter. Visible matter can be seen because it gives off light or reflects light given off by another object. Dark matter cannot be seen. It does not give off light or reflect light. Scientists believe that over ninety-percent of the matter in the Universe is dark matter. They also believe that by studying dark matter they will gain new information about the Universe. Some of the information they hope to discover is the size, shape and future of the Universe. Scientists also hope to learn about how galaxies formed by studying dark matter. Scientists cannot see dark matter, so they have a special way of studying it. Scientists study dark matter by looking at how it affects visible matter. Scientists use computers and satellites to study dark matter. The Hubble Space Telescope has taken pictures that have helped scientists discover where dark matter can be found.
Astrophysics Seminar Schedule Shedding New Light On The Nature Of dark matter Abstract. dark matter,first proposed by Swiss astrophysicist Fritz Zwicky in 1937 http://mactania.phsx.ukans.edu/astro-seminar/
Extractions: Observations of narrow radio-emitting filaments near the Galactic center may indicate a pervasive vertical (i.e. perpendicular to the Galactic plane) milliGauss magnetic field in the central 100-200 parsecs of the Galaxy. This presentation will describe how a field of this orientation and strength can arise from inflow of plasma in the Galactic disk, and also how such a strong magnetic field could be confined. April 20 th Daniel Hogan In the Principia, Isaac Newton mathematically demonstrates that Kepler's Three Laws of Planetary Motion can be explained in light of Newton's own proposed laws. Newton's proofs of this connection are discussed with an emphasis on his proof of Kepler's Second Law. It is shown that Newton's procedures involve the application of limits to geometrical figures, making these proofs surprisingly different from proofs of the same principles more commonly seen today.
Imagine The Universe! Dictionary A-D It was previously named the Advanced Xray Astrophysics Facility (AXAF dark MatterName given to the amount of mass whose existence is deduced from the analysis http://imagine.gsfc.nasa.gov/docs/dict_ad.html
Extractions: A quantity obtained by multiplying the mass of an orbiting body by its velocity and the radius of its orbit. According to the conservation laws of physics, the angular momentum of any orbiting body must remain constant at all points in the orbit, i.e., it cannot be created or destroyed. If the orbit is elliptical the radius will vary. Since the mass is constant, the velocity changes. Thus planets in elliptical orbits travel faster at perihelion and more slowly at aphelion . A spinning body also possesses spin angular momentum. apastron
1994 October Astrophysics Conference In Maryland The 1994 October Astrophysics Conference in Maryland is devoted toDark matter . Bulletin 1 (not available); Bulletin 2 (August 10 http://www.astro.umd.edu/october/1994.html
Inquiring Minds Fermilab participates in the experiment. Homepage of Cryogenic dark MatterSearch (CDMS) Experiment. Return to Astrophysics at Fermilab. http://www.fnal.gov/pub/inquiring/physics/astrophysics/colddarkmatter.html
Extractions: Based on thorough observations of the sky, astrophysicists noticed years ago that the shape and motion of galaxies and other objects cannot be explained with visible matter, the matter we know from stars and planets. The data suggested gravitional forces that can only be explained by what physicists called dark matter. Many speculations exist about the origin and composition of dark matter. The Cryogenic Dark Matter Search (CDMS) experiment is looking for dark matter in the form of Weakly Interacting Massive Particles, or WIMPs. One attempt to solve the dark matter problem hypothesizes the existance of an undiscovered particle already existed in the very early universe. One can calculate the abundance of these particles in the universe today. If these particles are to provide the mass necessary to prevent the universe from expanding for ever, their interaction with other matter must be very weak and their mass should be in the range 10 GeV to 10,000 GeV. (For comparison: the mass of a proton equals 1 GeV.) These properties gave rise to the name WIMP. Gravitational forces should keep WIMPs within our galaxy. We can imagine a cloud of WIMPs clumped around our galaxy, with the solar system sweeping through this cloud as we orbit the center of the Milky Way. WIMPs could easily travel through regular matter, like the earth, and the particles should have a mean velocity relative to the earth of about 300 km/s.
Penn Astrophysics Research students to join. Theoretical Astrophysics and Cosmology. dark MatterHalos and Weak Lensing (Jain, Takada, Jarvis, Dolney, Dobler) http://dept.physics.upenn.edu/astro-cosmo/research.html
Extractions: People Research Seminars Journal Club ... Department The astrophysics group in the Department of Physics and Astronomy at Penn currently consists of eight full time faculty, one lecturer, and a number of post-doctoral fellows, full-time staff, and graduate students (photos here ). We are in the process of hiring more faculty and plan to continue expanding our group over the next several years. Our areas of research include low-mass stars and their companions, variable stars, Kuiper-Belt objects, dark matter search, dark matter halos, the cosmic microwave background, and the development of new astronomical instrumentation and telescopes. Our research activities cover the full spectrum computations, instrumentation, observation, and theory. There are many exciting projects for students to join. Max Tegmark Angelica de Oliveira-Costa Bhuvnesh Jain Raul Jimenez ... Licia Verde Dark Matter Halos and Weak Lensing (Jain , Takada, Jarvis, Dolney, Dobler) One of the best ways of studying dark matter is through weak gravitational lensing, which is the shearing and magnification of light we receive from distant galaxies. Our research has focused on understanding how small fluctuations in the early Universe grew to form the large-scale structure observed today. We use theoretical modeling of weak lensing by large-scale structure for different cosmological models and are interested in the measurement of galaxy clustering parameters and their relation to the clustering of dark matter measured by lensing effects.
NERSC 2003 Annual Report Astrophysics Universe The Movie of long tails of luminous matter, formed by B. Allgood, and JR Primack, The darkside of the halo occupation distribution, Astrophysics Journal (submitted http://www.nersc.gov/research/annrep03/advances/1.1.universe.html
