1 / 34

Dark Puzzles of the Universe

Dark Puzzles of the Universe. Saturday Morning Physics (2007). Prof. Bhaskar Dutta and Prof. Teruki Kamon. Department of Physics Texas A&M University. Question. March 24, 2007. Dark Puzzles of the Universe. 2. Thinking of Our Universe. My Universe. March 24, 2007.

yaron
Download Presentation

Dark Puzzles of the Universe

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Dark Puzzles of the Universe Saturday Morning Physics (2007) Prof. Bhaskar Dutta and Prof. Teruki Kamon Department of Physics Texas A&M University Dark Puzzles of the Universe

  2. Question March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 2

  3. Thinking of Our Universe My Universe March 24, 2007 March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe Dark Puzzles of the Universe 3

  4. Message from the Universe How do we measure the content of the Universe? We look at the the oldest light which set out on its journey long before the Earth or even our galaxy existed. This light forms the background of the Universe: Cosmic Microwave Background (CMB) Measurement of this light tells us the story of the Universe. Dark Puzzles of the Universe

  5. The Most Distant Light CMB was emitted when the Universe was only380,000 years old. March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 5

  6. The Universe Pie Today, we discuss DM. March 24, 2007 March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe Dark Puzzles of the Universe 6

  7. Content of the Universe 4% The 23% is still unobserved in the laboratory.. (This new matter can not be seen visually!) We call this Dark Matter.. March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 7

  8. Existence of Dark Matter Examples of observations: We know the dark matter exist. Collision of the galaxies Rotation curves of the galaxies March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 8

  9. Cosmic Collision of 2 Galaxy Clusters 1 2 3 4 splitting normal matter and dark matter apart – Another Clear Evidence of Dark Matter – (8/21/06) Ordinary Matter (NASA’s Chandra X Observatory) time Approximately the same size as the Milky Way Dark Matter (Gravitational Lensing) March 24, 2007 March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe Dark Puzzles of the Universe 9

  10. Rotation Curves of the Galaxies Old observation March 24, 2007 March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 10

  11. What is Dark Matter? Neutral and long-lived object Can it be one of the known particles? Dark Puzzles of the Universe 11 March 24, 2007 March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe

  12. Building Blocks of Matter What are the elementary particles? Dark Puzzles of the Universe

  13. Zoo: 12 Particle Animals The elementary particles are fundamental building blocks of matter. 6 Types of Quarks 6 Types of Leptons All masses in MeV. ANIMAL MASSES SCALE WITH PARTICLE MASSES Dark Puzzles of the Universe

  14. Fantastic Four g g W G • Gluons (g) for strong force • Quarks experience them. • Protons & neutrons form. • Photons (g) for electromagnetic force • Quarks, leptons (other than neutrinos) experience this force. • W’s for weak forces • Quarks, leptons experience this force. NOTE : Graviton (G) (not found) carries gravitational force. Dark Puzzles of the Universe

  15. The Standard Model The Standard Model is a model which describes all these particles and 3 of 4 forces: We have confirmed the existence of SM in the laboratory experiments. So, can it explain our Universe? Dark Puzzles of the Universe

  16. Dark Matter Particle? x x x Quarks, electron, muon, tau particles, and force carriers can not be the dark matter, since their interactions are stronger than what we expect. Neutrinos can, but they have other problems. x x x x x x x x x x x x x We need a new model,called Supersymmetric Standard Model or SUSY.This model has a new charge-less (neutral) particle: Neutral-ino • What is the new model? • Can the neutralino be observed and consistent with the dark matter content of the Universe? Dark Puzzles of the Universe

  17. Dream of Unification Physicists always dream about unification of all the forces. The grand unification of the forces occur in theSUSY model. Dark Puzzles of the Universe

  18. Mirror Reflection Fermilab Boselab Dark Puzzles of the Universe

  19. Supersymmetric Reflection g  e  e   Lots of new particles!!!! Renamed as “chi one zero” But, one of them is neutralino. This is a leading candidate fordark matter particle. Dark Puzzles of the Universe

  20. When Were the Dark Matter Particles Created? Now ~ 0.0000001 seconds March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 20

  21. Thinking of Dark Matter Detection My Universe March 24, 2007 March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe Dark Puzzles of the Universe 21

  22. How Can We See Them in the Lab? µ detector One type of experiment: in deep underground Dark Matter particle Dark Puzzles of the Universe

  23. Collider One promising way: In collisions Dark Puzzles of the Universe

  24. Particle Collider One promising way: In particle collisions ➩ Tevatron and Large Hadron Collider Dark Puzzles of the Universe

  25. Physics Magic: Ping-pong balls  Steel Balls E = mc2 Proton and ant-proton collision can produce the Standard Model particles like heavy top quarks (~180 times heavier than a proton!) Dark Puzzles of the Universe

  26. CDF DØ Antiproton (p) Proton (p) Tevatron at Fermilab _ Dark Puzzles of the Universe

  27. Pattern Recognition [Tevatron] proton and anti-proton collide and produce the Standard Model particles as well as New Particles. In 1995,the CDF(*) and D0 collaborations co-discovered the top quark in ~4 trillion (4,000,000,000,000) collisions. [Q]We have 100 trillion collisons today. Can the Tevatron produce the neutralinos? [A] May not  [the neutralinos can be heavier.] (*) The TAMU group is one of charter members of the CDF collaboration. March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 27

  28. Large Hadron Collider (LHC) 7 times powerful than the Tevatron The LHC at CERN, scheduled for the first proton-proton collisions in 2007 in Switzerland, will have the smashing power of 14 Tera electron Volts (14,000,000,000 eV) - far larger than any other machine ever built. Two experimental groups, called ATLAS and CMS(*), will record the first collisions by the end of 2007. (*) The TAMU group is a member of the CMS collaboration. March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 28

  29. Collisions as We Imagine … March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 29

  30. More Pattern Recognition How do we produce the neutralinos at the LHC? We have to extract this reaction out of many trillion pp collisions. neutralinos (dark matter particles) March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 30

  31. How do you know that the neutralinos (we will observe) at the collider are responsible for the dark matter content? We measure the masses (m) of the particles at the LHC. We calculate the dark matter content (W) in the new model of the Universe. W =x(m) x y / z + g x h (m) - p (m)/ q + r (m)x 45 / 100 + 60 x ur (m) x ty + dx s (m) + j (m) x p (m)= 0.23 Dark Puzzles of the Universe

  32. Conclusion So far inthe laboratories we haveseen theparticlesresponsible for 4% of theuniverse. Theupcoming experiments will try toprobethe nature of 23 % of the universe: dark matter. Challenge: 73% of the universe is still a major puzzle. Not yet understood theoretically! March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 32

  33. Conclusion TO SOLVE THE PUZZLE OF THE UNIVERSE. So far inthe laboratories we haveseen theparticlesresponsible for 4% of theuniverse. Theupcoming experiments will try toprobethe nature of 23 % of the universe: dark matter. Challenge: 73% of the universe is still a major puzzle. Not yet understood theoretically! March 24, 2007 March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 33

  34. Any Question? March 24, 2007 March 24, 2007 Dark Puzzles of the Universe Dark Puzzles of the Universe 34

More Related