The Particle- And Astro-Physics Of Dark Matter The Particle and astro-physics of dark matter We review some recent determinations of the amount of dark matter on galactic, cluster, and large scales, noting some puzzles and their possible http://rdre1.inktomi.com/click?u=http://citebase.eprints.org/cgi-bin/citations?i
Extractions: Search The Infography: Through a Universe Darkly: A Cosmic Tale of Ancient Ethers, Dark Matter, and the Fate of the Universe, by Marcia Bartusiak, Harper, 1993. Chapter 5 of The Whole Shebang (A State of the Universe Report), by Timothy Ferris, Touchstone, Simon and Schuster, 1997. Dark Matter in Astro- and Particle Physics (Proceedings of DARK '96: Heidelberg, Germany, 16-20 September 1996), edited by H.V. Klapdor-Kleingrothaus and Y. Ramachers, Singapore and River Edge, NJ: World Scientific, 1997. Galactic Astronomy, by James Binney and Michael Merrifield, Princeton University Press, 1998. Supersymmtric Dark Matter, by Jungman, Kamionkowski, and Griest, Physics Reports, 267, 195 (1996). Dark Matter, by K. Ashman, Proceedings of the Astronomical Society of the Pacific, 104, 110 (1992). Science Magazine
CFHT Gives First Glimpse Of Dark Matter Distribution CFHT Gives First Glimpse of dark matter Distribution. More images here. Table of contents. Press release. Further scientific description. Images and captions. In depth technical description. Scientific team. Contact Information server for research papers (``astroph'') where the technical 8 Dept. of Physics, Johns Hopkins University, Baltimore, USA http://www.cfht.hawaii.edu/News/Lensing
Extractions: An international team of astronomers based in France has obtained the first-ever glimpse of the distribution of dark matter over a large section of sky. The team used images from the Canada-France-Hawaii Telescope's high-resolution wide-field imaging camera to analyze the light of 200,000 distant galaxies, looking for distortions caused by intervening dark matter. The results give cosmologists their first clear window into the possible roles of dark matter in the evolution of the Universe. The 13-member team, headed by Dr. Yannick Mellier of the Institut d'Astrophysique de Paris and the Observatoire de Paris, drew on a wide range of expertise, including cosmology, astrophysics, statistics, data analysis and instrument technology by bringing together researchers from France, Germany, Canada and the United States. The nature of dark matter is one of the greatest unsolved mysteries of modern science. While dark matter makes up at least 90% of the mass of the Universe, both its composition and its distribution are unknown. Knowledge of dark matter is, however, critical to understanding the evolution and fate of the Universe.
Extractions: Front Page Today's Digest Week in Review Email Updates ... Astro Particle Dark Matter (24 links) See Also: News about Dark Matter Chess Masters Are Quick On The Trigger (June 2, 2004) full story Gene At Root Of Urban Air Pollution's Lung Effects (June 1, 2004) full story Scientists Discover Undersea Volcano Off Antarctica (May 31, 2004) full story Geophysicist Discovers Why Earth 'Wobbles' (May 20, 2004) full story Chandra Opens New Line Of Investigation On Dark Energy (May 19, 2004) full story [ More news about Dark Matter
Ask A High-Energy Astronomer: Dark Matter questions unrelated to high energy astrophysics. Special Guidelines for Teachers.Ask your question about dark matter here, if it isn t excluded by the above http://imagine.gsfc.nasa.gov/docs/ask_astro/dark_matter.html
Extractions: Library of Past Questions First time visitors: Please be sure to read our main page What is dark energy, and what is dark matter? Could virtual WIMPS be the Dark Matter? What areas are at the forefront of Milky Way Studies? Can you tell me how dark matter affects galactic spin? Has there been any research with empirical results proving the existence of 'Dark Matter' Could the missing mass be around as energy from the Big Bang? ... Could mini-blackholes from the Big Bang be what Dark Matter is? Do you have a question that isn't answered in our archive?
Extractions: We review some recent determinations of the amount of dark matter on galactic, cluster, and large scales, noting some puzzles and their possible resolutions. We discuss the interpretation of big bang nucleosynthesis for dark matter, and then review the motivation for and basic physics of several dark matter candidates, including Machos, Wimps, axions, and neutrinos. Finally, we discuss how the uncertainty in the models of the Milky Way dark halo will affect the dark matter detection experiments. References and citations for this submission:
Imperial College Astrophysics: Teaching dark matter and Neutrino Astrophysics. Staff contactsTim Sumner, IgorLiubarsky. Search for Galactic dark matter. Evidence continues http://astro.imperial.ac.uk/Teaching/Postgrad/particleastro.html
Extractions: home research people contact ... Selected References m day This work is well funded at ICSTM with a 4-year rolling grant in place, with a team of about 8 people involved. PhD opportunities exist in both data analysis and detector development. The possible projects are very much instrument biased although there is some freedom to explore also relevant astrophysical aspects. To learn more look at the UK Dark Matter Search site The Antarctic Muon Neutrino Detector Array (AMANDA), located at the South Pole is currently the largest operating detector of neutrinos in the world. The detector is scheduled for expansion (IceCube) towards instrumentation of 1km of Antarctic ice. AMANDA has been collecting data since 1990. There are opportunities for AMANDA data analysis as well as preparatory work for IceCube. Of particular interest is the investigation of cataclysmic events that would produce neutrino emission as well as Gravitational Waves (see later section). Possible sources of such emissions could be the coalescence of blackhole-companion systems or collapsing supermassive stars. Both of these have been postulated as possible candidates to explain Gamma Ray Bursts (GRB).
Astrophysics Challenged By Dark Energy Finding of dark energy, normal matter and dark matter (an invisible exotic form of matter). otherscientists, the new finding holds promise for astrophysics. http://www.space.com/scienceastronomy/generalscience/darkenergy_folo_010410.html
Extractions: A strange repulsive force of "dark energy" pervades every nook and cranny of the universe, a team of scientists said earlier this month , but the force not only pushes against the master force of gravity it also has astrophysicists' heads spinning. While gravity gently binds planets, stars and galaxies together, dark energy tugs on the fabric of time and space, pushing galaxies apart ever faster and faster into the farthest reaches of the universe. The evidence came in a recent Hubble space telescope observation of the most distant supernova (exploding star) ever detected. The record-breaking supernova appears brighter than it should if the universe had been expanding at a steady rate. The new finding suggests that a decelerating universe holds galaxies relatively close together and objects in them would have appeared brighter because they would be closer. Images
Springer-Verlag - EPJC Direct PS13 Particle Astrophysics (dark matter) EPS 2003 High Energy Physics(HEP) conference PS 13-01 - Review of recent progress in http://www.springeronline.com/sgw/cda/frontpage/0,10735,5-40213-12-102588-0,00.h
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Springer-Verlag - EPJC Direct All, Go, Advanced Search. PS13 Particle Astrophysics (dark matter) EPS 2003 High Energy Physics (HEP) conference http://www.springeronline.com/sgw/cda/frontpage/0,10735,4-40213-12-102588-0,00.h
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Extractions: home research people contact ... Damped Lyman alpha galaxies Our Group at Imperial College consists of: Steve Warren (Senior Lecturer), Simon Dye (PPARC Post-doctoral Fellow) and Steve Weatherley (PhD Student). We have a general interest in the problem of dark matter, trying to map the distribution and determine the nature of the dark matter in galaxies and galaxy clusters. This includes a new study of the mass of the Milky Way using remote blue horizontal branch stars as tracers of the halo potential, as well as several gravitational lensing projects. Under the latter the interests of the group include cluster lensing, microlensing in the Virgo cluster, and galaxy-galaxy lensing. Under quasars we are interested particularly in surveys in the near-ir, both for dusty quasars, and quasars of very high redshift. We are also engaged in a study with HST of the galaxies that give rise to damped Lyman alpha absorption lines seen in quasar spectra. If you would like to know more about gravitational lensing we have here three interactive gravitational lens simulations The total mass of the Milky Way is a fundamental but very poorly measured quantity. The dark halo evidently extends beyond 100 kpc radius, and the main source of uncertainty in the mass is the small number of objects known at large Galactocentric radii: only 23 dwarf galaxies and globular clusters beyond r=25 kpc. We are undertaking a programme of photometry and spectroscopy of faint stars in the halo to increase the number of distant tracers to 100. We are looking for remote blue horizontal branch (BHB) stars. At high Galactic latitude, BHB stars can be selected by B-V colour. BHB stars are ideal as mass tracers as they are bright (M=0.7), abundant, and are standard candles, so distances can be measured. The main problem in this work is that samples of candidate BHB stars are contaminated by blue stragglers, which are less luminous dwarf stars. Click
Extractions: home research people contact ... Departmental Report Experimental Astrophysics T.J. Sumner, W.G. Jones (HEP), J.J. Quenby, G.K. Rochester, A. Bewick, A.S. Howard (HEP), I. Ivaniouchenkov, V. Lebedenko, I. Liubarsky, R. Luscher, D. Shaul per day per kg of target material. This new detector will get to 10 per day per kg, which is about two orders of magnitude better than our world competitors. In the meantime the UKDMC has just deployed a single-phase xenon instrument, ZEPLIN I, in the Boulby mine and this will use timing information in the primary pulse to provide some level of discrimination between the event types. In the longer term the UKDMC is developing direction gas chambers which will allow details study of the neutralino particle velocity distributions, hence providing direct information about the distribution of dark matter in our Galaxy. Figure 2 ZEPLIN III - a new advanced two-phase dark matter detector A project to start development work on a real-time low-threshold detector for solar neutrinos, SIREN, has just been funded. The "solar neutrino problem" is one of the long-standing major puzzles in astrophysics. The current generation of solar neutrino experiments give results which are not in agreement with advanced sophisticated solar models and are beset by complications as they are either long exposure radiochemical (with low-energy thresholds) or real-time water targets with high thresholds looking at neutrinos with different origins. Our proposal uses targets
The Interaction Point, January 23, 2004 Astrophysics Program Investigates dark matter By Linda DuShane White.Steve Kahns primary focus as Deputy Director of the Kavli http://www2.slac.stanford.edu/tip/2004/jan23/astrophysics.htm
Extractions: January 23, 2004 Back to SLAC Homepage Back to TIP Homepage In this issue: FRONT PAGE SPECIAL: SPEAR3 DEDICATION FEATURES POLICIES AND PROCEDURES EVENTS ABOUT TIP Astrophysics Program Investigates Dark Matter By Linda DuShane White Steve Kahns primary focus as Deputy Director of the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) is to develop major new programs. "As is essential for scientific programs at SLAC, two programs have been presented to and approved by the Experimental Program Advisory Committee (EPAC) in November 2003. So we have the green light to go forward," explains Kahn. These two programs are cornerstone elements of the new Kavli experimental program. Both are in the early stages, and both involve relatively substantial programs in experimental cosmology performed at SLAC. "Both of these projects are very visible national projects that have a prominent role in U.S. programs," Kahn added.
Economist.com | Cosmology enough to explain the irregularities without resorting to ghostly dark matter andenergy. in a December issue of Astronomy and Astrophysics, Sebastien Vauclair http://www.economist.com/science/displayStory.cfm?story_id=2404626
Cosmology: Physics Of The Universe 5/22/03 Solid State Plasma - The Conventional theory of dark matter gets Potent Fromthe University of California, San Diego Center for Astrophysics Space http://physics.about.com/cs/cosmology/
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Extractions: Dark Matter: Strong Gravitational Lensing Tony Tyson and Ayana Holloway (Lucent Technologies' Bell Labs) According to the General Theory of Relativity, mass warps space-time (this is what causes gravity). When light travels through space, then, its path is bent if it passes near large concentrations of matter. Thus, massive objects in the universe can act like huge magnifying glasses, distorting and concentrating light traveling around and through them. This effect is called gravitational lensing. This movie shows how it might work in a cluster of hundreds of galaxies. Strong Gravitational Lensing When light rays from a distant source bend around both sides of a massive object and cross near Earth, the effect is called "strong gravitational lensing." Strong lensing magnifies and distorts light from the source, and in some cases also produces multiple images of the source. This movie shows a simulation of strong lensing by a massive cluster of galaxies containing huge amounts of both visible matter and "dark matter." The light distortion effects are exaggerated in the movie, but generally speaking such effects are common since rich clusters of galaxies are the largest concentrations of matter in the universe. In fact, the patterns of distortion help astronomers determine the amount of dark matter in clusters, and how that matter is spread in the cluster - both of which tell a great deal about the behavior of matter in the cosmos as a whole.