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What constitutes the dark matter? Dr. Theo M. Nieuwenhuizen Institute for Theoretical Physics University of Amsterdam Sterrenwacht Vesta Oostzaan, 17-10-2009
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Outline What is dark matter? Where is it located? Two forms of dark matter: Macho’s and/or Wimp’s Searches Solutions
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Discovery of dark matter 1931 Jan Oort Leiden: motions in our galaxy are “too fast” perpendicular to galactic plane: stars should escape In the plane: stars should escape from their elliptic orbit Explanation: there is more matter than we see: dark matter 1900 - 1992 1932 Fritz Zwicky: clusters of galaxies They rotate too fast around each other Explantion: dark matter 1898 - 1974
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Rotation of galaxies Rotation speed nearly independent of location
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Andromeda Nebula in Ultraviolet (HST 2009)
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p PlanetDistance to sunRotation speed Mercurius0.45 AE48 km/s Aarde1 AE = 92 million mi30 km/s Jupiter5 AE13 km/s In solar system outer planets are slower In galaxies there must be matter out of the center Where is the dark matter?
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Explanantions Planets? MACHOs: Massive Astrophysical Compact Halo Objects Heavy particles (“cold dark matter”) ? WIMPs: Weakly Interacting Massive Particles Newton’s law is not valid? Hydrodynamics, fluid mechanics
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Hydrodynamics 400.000 yr after big bang: plasma becomes gas (hydrogen, He) Jeans 1904: formation of proto-clusters Gibson 1996: Viscosity leads to fragmentation in gas balls of a few earth masses If gas balls coagulate, stars form Then Jeans cluster becomes visible as globular cluster Most gas balls cool and freeze, their clusters are invisible
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Carl H. Gibson * 1935 Sir James Hopwood Jeans 1877-1946 100.000.000 Jeans clusters around Galaxy, 149 visible as globular star clusters. Those clusters form the galactic dark matter. Isothermal density distribution explains the large rotation speeds far from the center More than 2000 objects with earth Rudy E. mass observed in microlensing Schild *1942
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Omega Centauri: Globular star cluster in Milky Way Young blue stars, older yellow stars Star formation out of already present frozen gas balls took place in phases
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Helix planetary nebula Star exploded Became white dwarf Ca 40.000 “cometary knots” = proto-gas balls Ca 1 earth mass Galactic dark matter = gas balls of earth mass: Macho’s
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NGC-2623: Two galaxies inside each others dark matter? Jeans clusters warmed: new stars in young star clusters
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Antennae galaxies: Two colliding galaxies come within each others dark matter sphere. Along their trajectories they transform several cold Jeans clusters into young globular star clusters.
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Part 2: Cluster dark matter Abell 1689 cluster of galaxies “Nearby” z = 0.184 Einstein ring
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Incomplete Einstein ring at 100/h kpc Abell 1689 Center Everything is in circles: Dark Matter acts as crystal ball
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Incomplete Einstein ring at 143 kpc Abell 1689 Centrum Dark Matter acts as crystal ball right: oldest galaxy 12.8 billion year
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Cluster of galaxies Abell 370 Strongest gravitation lens 20 times stronger than A1689 Hubble, after last repair May 2009
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Description of lensing data of Abell 1689 Th.M. N. ’09: Consider quantum particles (fermions) in each others gravitation at a certain temperature. Measure Limousin et al, ApJ 2007 for local Tyson and Fischer ApJ 1995 mass density distance to center
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Neutrinos cause this lensing Known particles: proton, electron, neutron, photon Neutrino “little neutron”: neutral particle Predicted in 1930 by Wolfgang Pauli Lightest of all particles (not massless!) Mass now predicted with help of Abell 1689 cluster: Mass between 0,2 eV and 2 eV will be searched in Karlsruhe (2012)
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Biggest quantum structure in the Universe normalized density: # neutrino’s per cubic thermal length per degree of freedom distance to center N>1: quantum degenerate N=1: transition quantum-classical At r = 505 kpc = 1.6 million lightyear d = 2r = 3.2 million lightyear That is pretty large …
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Incomplete Einstein ring at 143 kpc Abell 1689 Center
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Summary Two kinds: Oort and Zwicky Dark Matter Oort Dark matter: Dark matter of galaxies is normal matter. Frozen gas balls of earth mass (MACHO’s) in Jeans clusters of ca 100.000 solar masses. Ca 100 million of those clusters in our Galaxy. 149 visible as old globular star cluster. Star formation in globular clusters explained: new stars formed out of frozen gas balls that are already present. Dwarf galaxy problem (10.000 stars, much dark matter) solved: Jeans cluster with still many frozen gas balls.
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Summary Oort Dark Matter in galaxies Zwicky Dark Matter in clusters of galaxies: “new” particle: neutrino with mass of 1,5 eV (WIMP) Many searches for all kinds of heavy particles were in vain: mass = keV, MeV, GeV, TeV, PeV ADMX, ANAIS, ArDM, ATIC, BPRS, CAST, CDMS, CLEAN, CRESST,CUORE, CYGNUS, (DAMA), DEEP, DRIFT, EDELWEISS, ELEGANTS, EURECA, GENIUS, GERDA, GEDEON, GLAST, HDMS, IGEX, KIMS, LEP, LHC, LIBRA, LUX, NAIAD, ORPHEUS, PAMELA, PICASSO, ROSEBUD, SIGN, SIMPLE, UKDM, XENON, XMASS, ZEPLIN. DAMIC, FERMI, ICECUBE, VERITAS. Neutrino mass between 0,2 eV and 2 eV is searched in Katrin experiment in Karlsruhe (2012).
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Gravitational hydrodynamics of large scale structure formation Th. M. N., Carl H. Gibson, Rudy E. Schild arXiv:0906.5087 Do non-relativistic neutrinos constitute the dark matter? Th. M. N. Europhysics Letters 86 (2009) 59001
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Psalm 118:22 The stone which the builders refused is become the head stone of the corner
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KArlsruhe TRItium Neutrino Experiments
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