חזי יצחק, מיכל וולטר

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26.11.13. , . http://www.boker.org.il/meida/negev/desert_biking/school/dark_matter/dark-matter-003.htm. ? . - PowerPoint PPT Presentation

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26.11.13 ,

http://www.boker.org.il/meida/negev/desert_biking/school/dark_matter/dark-matter-003.htm ? ...

Fritz Zwicky-1933 coma " ---> 10 ----> ""

http://imagine.gsfc.nasa.gov/docs/science/mysteries_l2/dark_matter.html

?

46

Triangulum Galaxy - . " "

Triangulum " 7 . Rotation Curves

The Solar SystemPlanetr[km*1000]r[km]T [day]Mercury579105791000087.97Venus1082001.08E+08224.7Earth1496001.5E+08362.2Mars2279402.28E+08686.98Jupiter7783307.78E+084332.71Saturn14294001.43E+0910759.5Uranus28709902.87E+0930685Neptun45043004.5E+0960109Pluto59135205.91E+0990550Rotation Curve for the Solar System Rotation curves for Saturns moon - 1967

"Fame is fleeting. My numbers mean more to me than my name. If astronomers are still using my data years from now, that's my greatest compliment."

"In a spiral galaxy, the ratio of dark-to-light matter is about a factor of ten. That's probably a good number for the ratio of our ignorance-to-knowledge. We're out of kindergarten, but only in about third grade. Vera RubinMilky way r[kpc]r[ly]265202.581503.5114104.5146705.5179306.7218427228207.5244509.53097010.33357811.53749012.54075013.34335814.54727015.55053016.55379017.55705018.560310Calculating the mass of Milky Way

NGC 2998

http://www.wolframalpha.com/entities/galaxies/NGC_2715/sv/bw/lm/ NGC 2715

NGC 3495

NGC 801

M33

1973

James Peebles (left) and Jeremiah Ostriker (right) found evidence for dark matter in their computer simulations. -

This map shows the pattern of temperature variations in the cosmic microwave background (CMB) measured with the WMAP satellite. WMAP made a differential measurement of the CMB temperature with two sensitive radio antennae mounted with a fixed displacement between them. As the satellite rotated, the radio antennae traced out temperature variations in the entire sky. The largest temperature differences (between the red and dark blue regions) are about 0.0004 K, and the characteristic angular size of the temperature variations is around 1 degree. By analyzing the detailed pattern in this map, WMAP scientists infer that less than 4 percent of the universe is ordinary matter, and 23 percent is dark matter. -

? CandidateMass rangeProsConsAstronomical objects (failed stars, black holes, MACHOs...)1050-1063eVRather conservative scenario; lensing searches effectiveAmount of ordinary matter made in Big Bang falls short of total dark matter we need; not detected via lensing searchesNeutrinos< 2 eVKnown to exist, and have mass so a natural candidateTiny neutrino mass inhibits clumping on small scales needed to hold galaxies togetherAxions10-6eVPostulated to solve a different problem altogether; dark matter aspect comes for freeTough to detectWeakly Interacting Massive Particles (WIMPs)1010eVPlausible class of new elementary particles that emerge from multiple theories beyond the Standard ModelHave evaded detection in accelerators to dateAlternative Gravity ScenariosN/ANo mysterious new matter needed, but rather a modification of gravityHard to reconcile with Bullet Cluster observations; theories seen as "inelegant"Dark Sector InteractionsN/ATwo new pieces of physics: exotic dark matter particles plus new interactions between them; might help reconcile experimentsAdded complexity; wider range of phenomenology; tougher to rule outCERN Axion Solar Telescope (CAST)

. 9.5 X .

- WIMP

The Large Underground Xenon (LUX) detector contains 350 kg of cold liquid xenon that will scintillate when it interacts with a WIMP. The liquid xenon, held in the blue oblong vessel in this cutaway diagram, sits inside an 8-meter-diameter by 6-meter-high tank of water that reduces background signals from gamma radiation by seven orders of magnitude. Isolated from other sources of radiation by almost 1500 meters of rock, LUX will improve sensitivity to WIMPs by a factor of 100 over previous methods.AMS-02 Alpha Magnetic Spectrometer

"- . . -2013 18 .

http://ams.nasa.gov/

PRL

- MOND'

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? PI The Mystery of the Dark Matter The physics of the 21st Century

Uranus A very badly behaved planetDiscovered by William Herschel in 1781 Period of revolution 84 years, average distance from the Sun is: 19 AU. After 1800, discrepancies started to be apparent between the planet position as predicted by theory and as measured in the sky

Uranus A very badly behaved planetDiscovered by William Herschel in 1781 Period of revolution 84 years, average distance from the Sun is: 19 AU. After 1800, discrepancies started to be apparent between the planet position as predicted by theory and as measured in the sky

Neptune Discovery Chronology In October 1845, Adams wrote to George Airy, the Astronomer Royal of Greenwich Observatory, claiming that he had solved the problem of Uranus' orbit, and stating the position where the unknown planet could be found.In December 1845 (just two months after Adams), Le Verrier independently published a short manuscript on the orbit of the missing planet.

Neptune was ultimately discovered by the German astronomer Johann Galle, on September 29, 1846, using Le Verriers predictions.