Cosmic Rays and High Energy Physics

1. Cosmic Rays and High Energy Physics John P. Wefel Department of Physics and Astronomy Louisiana State University Baton Rouge, LA 70803 USA

2. Cosmic Ray and High Energy Physics have a common Ancestral Heritage The Study of Natural Radiation in the late 1800’s and early 1900’s Electroscope

3. High Energy Physics -- The Very Early Years 1913 Franck and Hertz excited electron shells by electron bombardment. Wimshurst-type machines. 1906 Rutherford bombards mica sheet with natural Alphas (several MeV) and develops the theory of atomic scattering. 1911 Rutherford publishes theory of atomic structure. 1919 Rutherford induces a nuclear reaction with natural alphas. ………..Rutherford believes he needs a source of many MeV to continue research on the nucleus. This is far beyond the electrostatic machines then existing, but ............ 1928 Gamov predicts tunneling so perhaps 500 keV would suffice. 1928 Cockcroft & Walton start designing an 800 kV generator encouraged by Rutherford 1932 Generator reaches 700 kV and Cockcroft & Walton split lithium atom with only 400 keV protons. They received the Nobel Prize in 1951.

4. High Voltage Machines The Cockcroft-Walton pre-accelerator, built in the late 1960s, at the National Accelerator Laboratory in Batavia, Illinois.

5. Van de Graaff's very large accelerator built at MIT's Round HillExperiment Station in the early 1930s.

6. Galactic Cosmic Rays: Discovered about a hundred years ago • In 1912 Victor Hess became the first cosmic ray balloonist • Measured an increase in the background radiation as a function of altitude, but only up to about 17,000 feet • Received the 1936 Nobel Prize in Physics for this work 17,000 feet is the highest altitude Hess reached. Data measured in 2003 by a simple 400 gm student-built sounding balloon payload.

7. Understanding the nature of cosmic rays • 1920’s radiation was thought to be some form of high energy photon • Hence the name Cosmic RAYS • Large debate between the photon camp and those who believed cosmic rays were charged particles (Millikan vs Compton) • 1930’s cosmic rays proved to be high energy charged particles (but were they protons or electrons) • Effects due to Earth’s magnetic field (first ‘magnetic analyzer’) • Latitude survey on-board ships • East-West Effect • Confirmed CR as positive charged (some believed they were positrons which had been discovered some years earlier) • Penetrating power through blocks of lead proved most primaries were protons (used mountaintop labs for some of these studies) • 1937 - Discovery of muon Birth of elementary particle physics • 40’s and 50’s cosmic ray “beam” was used to obtain data for studies of ‘elementary particles’.

8. Extensive air showers P. Auger P. Auger Jungfraujoch W. Kolhörster et al., Naturwiss. 26 (1938) 576 P. Auger et al., Comptes renduz 206 (1938) 1721

9. New Detector Technology • Geiger-Muller Tubes • Allowed coincidence experiments • Used mostly in ground-based experiments • Nuclear Emulsion • Particle tracks made visible in thick photographic film (requires darkroom development) • Passive detector – Configurable • Data collected/analyzed after the flight • Techniques perfected in labs all over the world • Basis of many International collaborations • Used continuously for about 60 years Would benefit both Cosmic Ray and High Energy Physics

10. Cosmic Ray Interaction in a Nuclear Emulsion

12. Followed a bit later by: Photomultiplier Tubes Scintillation Detectors Cherenkov Counters Solid State (Silicon) Detectors and rapid advances in electronics

13. High Energy Physics -- The Early Years 1924 Ising proposes time-varying fields across drift tubes. This is "resonant acceleration", which can achieve energies above that given by the highest voltage in the system. 1928 Wideröe demonstrates Ising's principle with a 1 MHz, 25 kV oscillator to make 50 keV potassium ions. 1929 Lawrence, inspired by Wideröe and Ising, conceives the cyclotron. 1931 Livingston shows the cyclotron by accelerating hydrogen ions to 80 keV. 1932 Lawrence's cyclotron produces 1.25 MeV protons and he also splits the atom just a few weeks after Cockcroft and Walton (Lawrence received the Nobel Prize in 1939).

14. Leo Szilard and Ernest O. Lawrence

15. Leo Szilard (left) talks with Ernest O. Lawrence (right) at the American Physical Society meeting in Washington D.C., on April 27, 1935. The man in the background at upper left may be Walter Zinn. American physicist Ernest Lawrence received the 1939 Nobel Prize for inventing the cyclotron. Credit went to Lawrence, but Szilard invented it first. Szilard filed a German patent application on the cyclotron on January 5, 1929. Lawrence conceived the idea independently several months later. Lawrence's American patent application was not filed until January 26, 1932. First Cyclotron Lawrence’s cyclotron compared to the Nobel medal he received for it in 1939.

16. The 60 Inch Cyclotron Donald Cooksey and E.O. Lawrence

18. Back to Cosmic Rays

19. Brief Chronology • 1912-15 – Hess and Kolhorster Manned Flights • 1937 - Mu-Meson Discovered • 1947 – Pi-Meson Discovered • 1948 – Discovery of CR Helium and heavy elements • 1940-50’s – CR beam used for Elementary Particle Physics • 1957 – Sputnik-1 - ‘The Dawn of thr Space Age’ • 1961 – Primary Electrons and Gamma rays • 1966 Discovery of UH (Z>30) Elements in CR • 1979 – Identification of Anti-protons • 1970’s till – Isotopic Composition at low energy (mainly satellites)

20. ’The Age of ‘Plastic’ • Otto C. Winzen (1918-76) • General Mills: developed techniques to produce ultra-thin polyethylene • Winzen Research Inc. (1949) with wife Vera. Sold poly balloons to ONR • Projects Helios, Skyhook, Strato-lab, etc. • AF Reconnaissance (Moby Dick)

21. An Age of Discovery with Balloons • “Rubberized” Balloons (left) give way to the new Plastic Balloons • Balloon size and thus payload / altitude increases • New scientific disciplines • Propelled Cosmic Ray Physics • Beginning of High Energy (then called Elementary Particle) Physics • Gamma Ray Astronomy • X-ray Astronomy • UV Astronomy • Aids Solar and Galactic Astronomy • Remote Sensing • Atmospheric measurements • High Altitude human flight testing • Continuing technical advances

22. Brief Chronology • 1912-15 – Hess and Kolhorster Manned Flights • 1937 - Mu-Meson Discovered • 1947 – Pi-Meson Discovered • 1948 – Discovery of CR Helium and heavy elements • 1940-50’s – CR beam used for Elementary Particle Physics • 1957 – Sputnik-1 - ‘The Dawn of thr Space Age’ • 1961 – Primary Electrons and Gamma rays • 1966 Discovery of UH (Z>30) Elements in CR • 1979 – Identification of Anti-protons • 1970’s till – Isotopic Composition at low energy (mainly satellites)

23. The Dawn of the Space Age – Sputnik-1 1957 October 4 19:12:00 UTC Baikonur Cosmodrome 83.6 kg 58 cm diameter 4 antennas (2.4 – 2.9 m long) 20.005 and 40.002 MHz 92 day lifetime Iskustvennyi Sputnik Zemli (Fellow world traveler of the Earth)

24. The Space Program Evolves Sputnik -2 Launched Nov. 3, 1957 Explorer-I Launched Jan. 31, 1958 Sputnik – 3 Launched May 15, 1958 (1300 kg – first space environment laboratory) And there were many more satellites …. Explorers, Cosmos, Vanguard, Pioneers, IMP, OGO, OSO, Proton, Voyager, Sokol, to name just a few And many countries became involved in the Space Adventure Explorer-I launch Jan. 31, 1958

25. Space Age: Magnetospheric Physics Explorer-I carried the Geiger-Muller tube radiation experiment of James Van Allen which led to the discovery of trapped particles within the Earth’s magnetic field – the ‘birth’ of Magnetospheric Physics Dr. William H. Pickering, Dr. James A. Van Allen and Dr. Wernher von Braun (left to right) hoist a model of Explorer I and the final stage after the launch.

26. HEP -- The Era of Colliders In the 1950’s a number of places, MURA, Novosibirsk, CERN, Stanford, Frascati, and Orsay, developed the technology of colliding beams.( Bruno Touschek, Gersh Budker and Don Kerst, among others, were the people who made this happen.) • -- Electron – Positron • - Proton – Proton • -- Proton -- Anti-proton • -- Heavy Ion Colliders continue to be the source of the highest energy collisions

27. The first electron-positron storage ring, AdA. (About 1960) Built and operated at Frascati, Italy and later moved to take advantage of a more powerful source of positrons in France.

28. The CERN Electron Storage and Accumulation Ring (CESAR) was built, in the 1960’s, as a study-model for the ISR (Intersecting Storage Rings).

29. The first proton-proton collider, the CERN Intersecting Storage Rings (ISR), during the 1970’s. One can see the massive rings and one of the intersection points.

30. Superconducting RF cavities at the CERN Large Electron Positron Collider (LEP).

31. TEVATRON At FNAL The anti-proton source, the “p-bar” source, built in the 1990’s at Fermilab. The reduction in phase space density, the proper measure of the effectiveness of the cooling, is by more than a factor of 1011.

32. Space Age: Cosmic Ray Astrophysics ACE: Advanced Composition Explorer (below) Launched in 1997 & is still returning data L1 Halo orbit Goals: Determine charge state, elemental and isotopic composition of solar corona, solar wind, interplanetary particles, Interstellar medium and galactic particles over a broad energy range IMP-8 (J): Interplanetary Monitoring Platform (above) Launched in 1973 & returned data for over 30 years ! Elliptical orbit 45 x 25 Earth radii Goal: study magnetic fields, plasmas and energetic particles in near-Earth space

33. Satellites such as IMP-8 gave Elemental Composition Circles – Satellite and Balloon measurements Diamonds – Solar System Abundances • ‘Similar’ to Solar System (Local Galactic) Composition • Major differences at rare elements (Li, Be, B, odd-Z, sub-Fe) •  Nuclear Interactions in the Interstellar Medium (ISM) • Nuclear Physics input needed • Secondary to Primary ratios provide important information on Galactic Transport (Propagation) Relative to Si = 100

34. While ACE measured the Isotopic Composition of Cosmic Ray Matter

35. Investigating High and Very High Energy Cosmic Rays(Combination of Space-based, Balloon-based, and Ground-based Measurements) SPACE: PROTON Satellites (Naum Grigorov & Colleagues – (MSU) SOKOL Mission, HEAO-C2, CRN (Spacelab 2), PAMELA, AMS …. BALLOON: JACEE, RUNJOB, ATIC, TRACER, CREAM, TIGER …. GROUND: Extensive Air Showers (Technique used to discover the ‘knee’ at a few PeV by G. Khristiansen and colleagues) -- many arrays GOAL: Extend Space and Balloon measurements to higher energy and Air Shower measurements to lower energy until there is significant overlap.

36. Connections – Cosmic Ray and High Energy Physics Technology– Detectors, Electronics, DAQ, Software (Need to adapt HE systems and techniques to the space/near space environment.) Modeling and Simulations -- Need accelerator data as input to model the extensive air showers that must be studied to extend Cosmic Ray measurements to the highest energies. Instrument Development and Calibration – need accelerator beams at the highest possible energies for a variety of ions.

37. And Today …….. TheLHCat CERN And one of the big experiments CMS And …. in Space

38. AMS: A TeV precision, multipurpose spectrometer TRD Identify e+, e- Particles and nuclei are defined by their charge (Z) and energy (E ~ P) TOF Z, E 1 TRD Magnet ±Z Silicon Tracker Z, P TOF 2 3-4 5-6 Tracker 7-8 TOF RICH Z, E RICH ECAL E of e+, e-, γ 9 ECAL Z, P are measured independently from Tracker, RICH, TOF and ECAL

39. From The First Cyclotron to the Highest Energies in the Universe Let the ‘ride’ continue …….. First Cyclotron Pierre Auger Observatory