Charting a Course to the Energy Frontier Breese Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 B. Quinn Mississippi University of
On the edge of discovery… “The field of elementary particle physics is entering an era of unprecedented potential. ” “We concluded that this might be the most exciting moment in particle physics in a generation. ” Harold T. Shapiro, Princeton Univ. , Chair EPP 2010 Norman Augustine, Lockheed Martin, Chair NAS “Gathering Storm” Cmte. “…increased support of the physical sciences, engineering, and mathematics [is] essential to U. S. competitiveness … particle physics is a key priority within the physical sciences. . . Without question, the United States should be a leader in this great scientific adventure. ” B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 2
On the edge of discovery… “Rising Above the Gathering Storm” Report commissioned by the National Academy of Sciences to advise Congress of policy actions that they “could take to enhance the science and technology enterprise so that the U. S. can successfully compete, prosper, and be secure in the global community of the 21 st century. ” Norman R. Augustine chaired the committee formed to respond to the request. Retired Chairman and CEO of Lockheed Martin, serves on PCAST, served as undersecretary of the Army, recipient of National Medal of Technology Found that U. S. leadership in science and technology is eroding rapidly, and one of four main recommendations was to focus attention and resources to basic research. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 3
On the edge of discovery… “Revealing the Hidden Nature of Space and Time: Charting the Course for Elementary Particle Physics” (EPP 2010) Report is part of National Academies’ decadal review of all branches of physics Harold T. Shapiro chairs the Committee on Elementary Particle Physics in the 21 st Century which produced the report President Emeritus of Princeton Univ. , Professor of Economics, member Institute of Medicine, serves on PCAST Committee members are half particle physicists, quarter other physicists, quarter non-physicists. Norm Augustine is a member Charged to recommend priorities for the U. S. particle physics program for the next 15 years. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 4
On the edge of discovery… “The availability of technologies that can explore directly an energy regime known as the Terascale is especially exciting. The direct exploration of the Terascale could be the next important step toward resolving questions that human beings have asked for millennia: What are the origins of mass? Can the basic forces of nature be unified? How did the universe begin? How will it evolve in the future? Moreover, at Terascale energies, formerly separate questions in cosmology and particle physics become connected, bridging the sciences of the very large and the very small. ” - EPP 2010 report B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 5
… at a moment of challenge … “Many of the major particle physics facilities in the United States are being closed or converted to other uses. ” “Funding for particle physics in the United States has stagnated for more than a decade. ” “Within a few years, the majority of U. S. experimental particle physicists will be working on experiments that are being conducted in other countries” “The U. S. program in particle physics is at a crossroads. ” B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 6
… follow a bold vision. The United States should remain globally competitive in elementary particle physics by playing a leading role in the worldwide effort to aggressively study Terascale physics Chief recommendation of the EPP 2010 Committee B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 7
Outline Physics Opportunities Terascale Physics Dark Matter and Dark Energy Neutrino Physics Precision measurements of charged leptons and quarks Proposed action items and projects What roles Ole Miss will play B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 8
Physics: Background Decades of amazing theoretical and experimental success have resulted in the Standard Model (SM) EM Strong } Weak H B. Quinn University of Mississippi Higgs up/down strange charm bottom top photon gluon W/Z electron e-neutrino muon mu-neutrino tau-neutrino Higgs Ole Miss Physics Colloquium 11/28/06 1968 1964 1977 1995 1905 1979 1983 1897 1956 1937 1962 1976 2000 200? SLAC BNL SLAC/BNL Fermilab, D 0/CDF Planck/Einstein DESY CERN Thomson Reactor Cosmic Rays BNL SLAC Fermilab ? ? ? 9
Physics: Background EM Strong } Weak H B. Quinn University of Mississippi This model has successfully described or predicted almost everything we’ve seen in almost 100 years of particle physics – back to when the universe was 10 -12 seconds old. However we know the SM breaks down at the Te. V energy range – Terascale. SM does not tell How Electroweak symmetry is broken How particles acquire mass How gravity relates … Higgs Ole Miss Physics Colloquium 11/28/06 10
Physics: Terascale OPEN QUESTIONS The question of mass: How do elementary particles acquire their mass? How is the electroweak symmetry broken? Does the Higgs boson –postulated within the Standard Model- exist? The question of undiscovered principles of nature: Are there new quantum dimensions corresponding to Supersymmetry? Are there hidden additional dimensions of space and time? Are there new forces of nature? The question of the dark universe: What is the dark matter in the universe? What is the nature of dark energy? The question of unification: Is there a universal interaction from which all known fundamental forces, including gravity, can be derived? The question of flavor: Why are there three families of matter? Why are the neutrino masses so small? What is the origin of CP violation? B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 11
Physics: Terascale Both current theory and experimental data indicate that answers to several of these questions will lie in the Te. V range. e. g. Discovery of a SM Higgs boson Data from the LEP collider excludes a SM Higgs with mass below 114 Ge. V. Theoretical arguments require a Higgs mass below 1 Te. V. Signatures from Supersymmetry or extra spatial dimensions should show up at masses no greater than 1 Te. V Current energy frontier is at Fermilab’s Tevatron collider, with 1. 96 Te. V proton-antiproton center of mass energy. New particle reach up to ~0. 2 Te. V Higgs search at the Tevatron will just scratch the surface B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 12
Physics: Terascale The next step: the Large Hadron Collider (LHC) at CERN in Geneva: 14 Te. V proton-proton center of mass Te. V range constituent collision energies: can probe the entire range of expected Higgs mass. Will reveal whether the Higgs or Te. V-scale Supersymmetry exist. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 13
Physics: Terascale Whereas the LHC will be a powerful discovery device, a precision measurement instrument will be necessary to determine the properties of the things found at the Terascale. The proposed International Linear Collider (ILC) would collide electrons and positrons at up to 0. 5 Te. V (eventually 1 Te. V) Full CM energy available in clean environment with full knowledge of quantum state of the collisions Could determine whether discovered Higgs fully accounts for measured particle masses B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 14
Physics: Terascale Whereas the LHC will be a powerful discovery device, a precision measurement instrument will be necessary to determine the properties of the things found at the Terascale. The proposed International Linear Collider (ILC) would collide electrons and positrons at up to 0. 5 Te. V (eventually 1 Te. V) Full CM energy available in clean environment with full knowledge of quantum state of the collisions Could determine whether discovered Higgs fully accounts for measured particle masses B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 15
Physics: Dark Matter What do we know about dark matter? It exists and makes up ~23% of the universe’s energy density. Presence inferred from gravitational influence. Galactic rotational curves, gravitational lensing, large-scale structure, etc. What it is not: Hot, relativistic dark matter (e. g. neutrinos) Neutrinos mass could make up only a small fraction of the observed dark matter density; small-scale structure demands non-relativistic dark matter Baryonic: non-luminous gas, brown dwarfs, MACHOs (neutron stars, black holes) WMAP/CMBR/SDSS: baryon number density and total matter density measurements show non-baryonic matter is dominant Cold, non-baryonic dark matter candidates are favored e. g. WIMPs (Weakly Interacting Massive Particles) such as the neutralino, or lightest SUSY partner of photon, Z, neutral Higgs mixture B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 16
Physics: Dark Matter How could we observe WIMPs? Direct detection of atomic nuclei recoil from elastic scattering with WIMPs e. g. crystal cryogenic detectors like CDMS, using Ge and Si crystal masses cooled to sub-Kelvin (suppress thermal noise), deep underground (suppress cosmic ray background) B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 17
Physics: Dark Matter How could we observe WIMPs? Indirect detection by observing high-energy particles from cosmic WIMP annihilations e. g. GLAST search for high-energy gamma rays WIMP production in colliders Tevatron: experimental reach limited to small region of parameter space, but complementary to existing direct searches LHC: likely to find evidence for dark matter particles, but to identify them or between models ILC: study WIMP quantum numbers and combine with direct observation results to identify dark matter B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 unlikely distinguish 18
Physics: Dark Energy We’re essentially clueless about 70% of the universe See Hakeem M. Oluseyi’s 10/24/06 colloquium on SNAP for the details B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 19
Physics: Neutrinos We now know that neutrinos have mass! But it’s not your father’s fundamental particle mass… At least a million times lighter than the next lightest ν oscillations: unlike in quark mixing, two ν mixing angles are large ν could be their own antiparticles Extremely light masses could be result of GUT scale physics Important questions: What are the ν masses, and is the spectrum similar to charged leptons and quarks or inverted? What is the mixing pattern? How large is θ 13? Are ν own antiparticles? Normal m Inverted Do ν violate CP? n 2 n 3 n 1 B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 20
Physics: Neutrinos Are ν their own antiparticles? If so… Only constituents of matter that are Baryon number conservation has no leptonic analog Supports see-saw mechanism of ν (more later) How to answer? Nuclear expts searching for ν-less β decay B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 21
Physics: Neutrinos How large is θ 13? Size will help discriminate between different ν mass models e. g. see-saw mechanism in which ν masses arise from GUT-scale physics - the extremely light ν have extremely heavy “see-saw” partners produced in the hot Big Bang Big influence on determining ν mass hierarchy and CP violation How to answer? Reactor νe disappearance experiments νe P = sin 22θ 13 sin 2Δ 31 + cos 4θ 13 sin 22θ 12 sin 2Δ 21 B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 22
Physics: Neutrinos What is the mass hierarchy? Is CP violated? See-saw expects normal hierarchy – inverted would indicate a new symmetry producing the nearly degenerate high mass ν pair. If light ν violate CP, so would heavy see-saw partners Could explain the matter-antimatter asymmetry in our universe How to answer? Accelerator νe appearance experiments Rates are sensitive to θ 13, sign of the mass difference, and CP violating phase MINOS experiment at Fermilab nm Disappearance (2 flavors): P(nm→ nm) = 1 - sin 22 q 23 sin 2(1. 27 Dm 232 L/E) ne Appearance: P(nm→ ne) ≈ sin 2 q 23 sin 22 q 13 sin 2(1. 27 Dm 231 L/E) ν e appearance underway Where L, E are experimentally optimized and q 23, q 13, Dm 232 are to be determined Future experiments would be sensitive to evidence of CP violation B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 23
Physics: High-precision measurements Heavy Flavor Physics High-precision measurements in the heavy quark sector are tests of the SM Study rare loop-induced processes that can reveal significant virtual effects from new physics present at higher energy scales than are directly accessible CP violation in meson decays Discovered, and SM CP violation measured first in kaon decays B-factories established SM CKM matrix CP violation mechanism. Unitarity conditions on CKM elements allow depiction as a triangle in the complex plane. Tevatron and LHC offer opportunity to search for CP violation in the top quark sector, which would indicate new physics B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 24
How to move forward “Rising Above the Gathering Storm” report from the National Academies was the culmination of many such reports, and finally got the ear of the President. “…increased support of the physical sciences, engineering, and mathematics [is] essential to U. S. competitiveness …” Led to the inclusion of physical sciences in the State of the Union, and the proposal of the American Competitiveness Initiative (ACI) which calls for a doubling of the Nation’s investment in physical science research over 10 years DOE Office of Science, NSF, and NIST combined Historic opportunity for the advancement of physical sciences B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 25
Will the rising tide lift all boats? “ … particle physics is a key priority within the physical sciences. . . Without question, the United States should be a leader in this great scientific adventure. ” ACI proposed, House passed budget: DOE Office of Science: up 14. 1% Office of HEP: up 8. 1% ILC R&D: up 100% Time to articulate the plan for maintaining a leadership role in the field. Committee on Elementary Particle Physics in the 21 st Century (EPP 2010): “Revealing the Hidden Nature of Space and Time: Charting the Course for Elementary Particle Physics” Particle Physics Project Prioritization Panel (P 5): “P 5 Report: The Particle Physics Roadmap” B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 26
EPP 2010 chief recommendation The United States should remain globally competitive in elementary particle physics by playing a leading role in the worldwide effort to aggressively study Terascale physics B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 27
EPP 2010: Strategic Principles 1. The committee affirms the intrinsic value of elementary particle physics as part of the broader scientific and technological enterprise and identifies it as a key priority within the physical sciences. 2. The U. S. program in elementary particle physics should be characterized by a commitment to leadership within the global particle physics enterprise. 3. As the global particle physics research program becomes increasingly integrated, the U. S. program in particle physics should be planned and executed with greater emphasis on strategic international partnerships. The United States should lead in mobilizing the interests of international partners to jointly plan, site, and sponsor the most effective and the most important experimental facilities. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 28
EPP 2010: Strategic Principles 4. The committee believes that the U. S. program in elementary particle physics must be characterized by the following to achieve and sustain a leadership position. Together, these characteristics provide for a program in particle physics that will be lasting and continuously beneficial: • A long-term vision, • A clear set of priorities, • A willingness to take scientific risks where justified by the potential for major advances, • A determination to seek mutually advantageous joint ventures with colleagues abroad, • A considerable degree of flexibility and resiliency, • A budget consistent with an aspiration for leadership, and • As robust and diversified a portfolio of research efforts as investment levels permit. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 29
EPP 2010: Strategic Principles 5. The Secretary of Energy and the Director of the National Science Foundation, working with the White House Office of Science and Technology Policy and the Office of Management and Budget and in consultation with the relevant authorization and appropriations committees of Congress, should, as a matter of strategic policy, establish a 10 - to 15 - year budget plan for the elementary particle physics program. 6. A strong and vital Fermilab is an essential element of U. S. leadership in elementary particle physics. Fermilab must play a major role in advancing the priorities identified in this report. 7. A standing national program committee should be established to evaluate the merits of specific projects and to make recommendations to DOE and NSF regarding the national particle physics program in the context of international efforts. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 30
EPP 2010: Action Items Assume a budget rising with the rate of inflation for constant effort (well within ACI forecasts). Six action items in ranked priority order. Cornerstone is direct exploration of the energy frontier at the LHC and ILC, representing a 20 year campaign. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 31
EPP 2010: Action Items 1. The highest priority for the U. S. national effort in elementary particle physics should be to continue as an active partner in realizing the physics potential of the LHC experimental program. LHC begins operations 2007, taking physics quality data 2008. Center of gravity for the field for the next 15 years U. S. has already invested > $500 M Ole Miss’ LHC Involvement on the Compact Muon Solenoid (CMS) experiment: Hadronic calorimeter (HCAL) Forward Pixel vertex detector GFLASH fast simulation package Top quark and black hole physics B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 32
CMS B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 33
CMS B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 34
EPP 2010: Action Items 2. The United States should launch a major program of R&D, design, industrialization, and management and financing studies of the ILC accelerator and detectors. Global Design Effort (GDE) will present an initial cost estimate based on a reference design in about a month. Technical Design Report needs to be in hand in 2009 Ole Miss’ ILC Involvement: Completed: Accelerator R&D Detecting RF cavity breakdown with acoustic emission Reduction of beam halo with diamond quartz detectors Proposed: Si. D experiment Quinn (D 0 silicon), Cremaldi (CMS FPix) Jim Reidy: former ILC Detector R&D program manager for DOE B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 35
EPP 2010: Action Items 3. The United States should announce its strong intent to become the host country for the ILC and should undertake the necessary work to provide a viable site and mount a compelling bid. ILC in the U. S. will inspire and attract future students to study physics here, and keep the field vital in the U. S. Hosting the ILC will mean funding about half the cost, which will require an increase in resources for particle physics. International process will determine siting (U. S. , Europe, or Japan). Fermilab will be the natural and highly advantageous U. S. site with its existing infrastructure. Ole Miss’ Involvement in pushing to host the ILC: Quinn, Congressional and Administration advocacy as Government Relations chair of Fermilab’s User Executive Committee Reidy, ILC Detector R&D program manager B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 36
EPP 2010: Action Items 4. Scientific priorities at the interface of particle physics, astrophysics, and cosmology should be determined through a mechanism jointly involving NSF, DOE, and NASA, with emphasis on DOE and NSF participation in projects where the intellectual and technological capabilities of particle physicists can make unique contributions. The committee recommends that an increased share of the current U. S. elementary particle physics research budget should be allocated to the three research challenges articulated below. The direct detection of dark matter in terrestrial laboratories, the results of which could then be combined with measurements of candidate dark matter particles produced in accelerators. The precision measurement of the cosmic microwave background (CMB) polarization, which would probe the physics during the inflation that appears to have occurred within a tiny fraction of a second following the big bang. The measurement of key properties of dark energy. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 37
EPP 2010: Action Items 5. The committee recommends that the properties of neutrinos be determined through a well-coordinated, staged program of experiments developed with international planning and cooperation. A phased program of searches for the nature of neutrino mass (using neutrinoless double-beta decay) should be pursued with high priority. DOE and NSF should invite international partners in order to initiate a multiparty study to explore the feasibility of joint rather than parallel efforts in accelerator-based neutrino experiments. Major investments in this area should be evaluated in light of the outcome of this study. Longer-term goals should include experiments to unravel possible charge-parity (CP) violation in the physics of neutrinos and renewed searches for proton decay. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 38
EPP 2010: Action Items 6. U. S. participation in large-scale, high-precision experiments that probe particle physics beyond the Standard Model should continue, but the level of support that can be sustained will have to be very sensitive to the overall budget picture. Only very limited participation will be feasible in budget scenarios of little or no real growth. Participation in inexpensive, smallscale, high-precision measurements should be encouraged in any budget scenario. e. g. future B-factory, lepton flavor violation, rare decays, muon g-2 measurement Ole Miss’ Involvement in heavy flavor precision measurements Ba. Bar experiment at SLAC CP asymmetries, rare decays Godang serving with the Heavy Flavor Averaging Group DØ experiment at the Tevatron and CMS at the LHC top quark CP violation B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 39
Heavy Quarks - Ba. Bar Measurement of timedependent CP asymmetries and constraints on sin(2β+γ) B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 40
Heavy Quarks – DØ, CMS Measurement of top quark CP violating effects in ttbar pair and single top production B. Quinn University of Mississippi DØ Ole Miss Physics Colloquium 11/28/06 41
P 5 Roadmap B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 42
Conclusions Ø Particle physics is on the verge of one of the most exciting periods of discovery in its history. Ø It is coinciding with the best U. S. funding prospects in many years. Ø The U. S. particle physics community has developed an ambitious and aggressive plan to maintain a leadership role at the energy frontier. Ø Ole Miss will be making many contributions investigating the Terascale in the next several years. B. Quinn University of Mississippi Ole Miss Physics Colloquium 11/28/06 43
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