Presented by Morgan Catha Physics 422, Fall 2012
WIMPs are hypothesized to be captured by Sol. Subsequent annihilations may produce neutrinos. These excess neutrinos might be detectable from Earth. Existing neutrino detectors are well suited for this search.
One of 5160 Digital Optical Modules installed below the Antarctic ice to depths of2450 meters. The photomultiplier tubes within the pressure spheres record Cherenkovradiation from muons created by neutrino interactions in the ice. Data is transmittedto the surface along cables for storage and processing.
Antares is mounted in the Mediterranean Sea near Toulon, France. Its design issimilar to that of IceCube – photomultiplier tubes mounted within pressure spheressubmerged within a shielding medium, detecting Cherenkov radiation from muonscreated by interactions of neutrinos emerging upward through the Earth’s crust.
The Kamioka Observatory sits below 1000 metersof rock in the Hida Mountains of central Japan.The neutrino detector consists of a cylindricalchamber lined with 11,146 Hamamatsu PMTs andfilled with 50,000 tons of pure water. In 2001, a chain reaction caused over half of thetubes immersed in water to implode. The tubes now all have acrylic shields.
The Fermi gamma ray space telescope wasThe Fermi space telescope was launched by NASAlaunched by NASA in 2008 to gatherdata on cosmic gamma rays. This craftmay be able to observe gamma rays created by WIMP annihilations in the galactic halo.
PICASSO, located at SNOLAB, is a direct WIMP detector that uses superheateddroplets of perfluorobutane suspended in an elastic polymer. When a WIMP collideswith an atom in one of the droplets, the atom recoils and heats up the bubble,triggering an explosive conversion to vapor. The resulting acoustic pulse is picked upby piezoelectric sensors mounted around the gel.
DEAP-3600, currently under construction atSNOLAB, uses a volume of liquid argon as ascintillation material to detect WIMPs. Like theNeutrino detectors, it uses an array of PMTs todetect the light resulting from collision events.
XENON100 is a scintillation detector located at Gran Sasso underground laboratory inItaly. It uses 161 kg of liquid Xenon, which has similar ionization and scintillationproperties to Argon. The measured ratio of ionization to scintillation allowsResearchers to determine what type of particle interacted within the liquid.
DRIFT II uses a carbon disulphide gaseous time projection chamber to detectionizations caused by WIMP collisions. A 3-D map of the ionization left by thescattering event is constructed by measuring the times at which the ions arrive at theanode endplate.
CDMS II, located in the Soudan Mine Underground Laboratory in Minnesota, usesultra cold germanium crystals to detect ionization and phonons produced by WIMPinteractions. When a WIMP collides with a nucleus in the crystal, the resultingrebound causes the entire crystal lattice to vibrate. Microscopic strips of tungsten atthe edge of the crystal are held at the transition point between superconducting modeand normal. The phonon energy transferrals to the tungsten are thus registered aslarge changes in resistivity. This apparatus is held at as low as 10 mK temperature.
Joseph Giannetti’s mural next to the MINOS neutrino detector in Soudan Mine.
CAST consists of a nine tesla dipole magnet pointed at Sol. Axions generated in thesolar plasma are expected to convert to x-rays after entering the magnetic field via thePrimakov effect. X-ray detectors are located at either end of the tube. Thisexperiment has been conducted using vacuum, helium-4, and helium-3 inside themagnet bore in order to scan different energy ranges for the proposed axion.
ADMX, located at the University of Washington’s Centerfor Experimental Nuclear Physics and Astrophysics, uses aneight tesla magnetic field in a resonant microwave cavity todetect axions decays via the Primakov effect. The apparatusis supercooled with liquid helium to a temperature of 4.2degrees Kelvin. The resonant frequency of the chamber ischanged by adjusting the position of the tuning rods. Axiondecays are detected with superconducting quantuminterference devices (SQUIDs).
WIMP detection experiment results as of July 2012.
Axion detection experimental results as of March 12, 2012.
Timothy J. Sumner, "Experimental Searches for Dark Matter", Living Rev. Relativity 5,(2002), http://www.livingreviews.org/lrr-2002-4 (November 29, 2012)“IceCube in Depth”, IceCube Neutrino Observatory,http://icecube.wisc.edu/science/depth (November 29, 2012)Icecube Neutrino Observatory images courtesy of the National Science Foundation.Thierry Stolarczyk, “Overview of the ANTARES experiment”, ANTARES home page,http://antares.in2p3.fr/index.html (November 29, 2012)ANTARES module image property of Camille Moirenc for the ANTARES collaboration.ANTARES computer model property of F. Montanet, the French National Center forScientific Research, and the University of Joseph Fourier.Yusuke Koshio, “Details of Super-Kamiokande”, Super-Kamiokande Official Homepage,http://www-sk.icrr.u-tokyo.ac.jp/sk/detector/detail-e.html (November 29, 2012)Kamiokande detector graphics property of Kamioka Observatory, University of Tokyo.Lynne Jenner, “Fermi Spacecraft and Instruments”, Fermi Gamma-ray Space Telescope,http://www.nasa.gov/mission_pages/GLAST/spacecraft/index.html (November 29, 2012)Fermi space telescope images courtesy of NASA and Stanford University.
Picasso render property of Alex Pepin and Martin Auger.“Detector Concept”, The Picasso Experiment,http://www.picassoexperiment.ca/experiment.php (November 30, 2012)DEAP-3600 schematic courtesy of DEAP Project, Queen’s University at Kingston.“Liquid argon based Dark Matter detection”, The DEAP Experiment,http://deap.phy.queensu.ca/ (November 30, 2012)Aprile, E., et al. (2010, May 3). First dark matter results from the XENON100 experiment.Physical Review Letters , 105:131302. Retrieved December 1, 2012, from the arXivdatadase.XENON detector image courtesy of the University of Zurich.XENON schematic property of Alan Stonebraker.DRIFT II graphics courtesy of the U.K. Dark Matter Collaboration.“DRIFT (Directional Recoil Identification From Tracks)”, Sheffield Particle Physics: DarkMatter, http://drift.group.shef.ac.uk/ (December 1, 2012)“The Experiment”, CAST – CERN Axion Solar Telescope,http://cast.web.cern.ch/CAST/CAST.php (December 1, 2012)
“Experiment”, ADMX | Axion Dark Matter eXperiment,http://www.phys.washington.edu/groups/admx/experiment.html (December 1, 2012)ADMX images courtesy of the ADMX Collaboration and CENPA.“The Experiment”, Super Cryogenic Dark Matter Searchhttp://cdms.berkeley.edu/experiment.html (December 1, 2012)CDMS II apparatus photos courtesy of the SuperCDMS Collaboration.MINOS mural photo courtesy of flickr member WMGoBuffs.Aprile, E., et al. (Nov. 2, 2012). Dark Matter Results from 225 Live Days ofXENON100 Data. Physical Review Letters, Phys. Rev. Lett. 109, 181301. RetrievedDecember 1, 2012, from the arXiv datadase.J. Beringer et al. (Revised March 12, 2012 by L.J. Rosenberg and G.G. Raffelt). Axionsand other similar particles. (Particle Data Group), PR D86, 010001 (2012).