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Theme Group 2 Experimental Physics: Testing and Measuring Fundamental Processes. Six research areas: particle physics, particle astrophysics, cosmic rays, nuclei, gravity and quantum electronics. Theme Group 2 – Experiment - Overview. Experimental High Energy Physics (6 teaching faculty)
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Theme Group 2 Experimental Physics: Testing and Measuring Fundamental Processes Six research areas: particle physics, particle astrophysics, cosmic rays, nuclei, gravity and quantum electronics Theme Group 2
Theme Group 2 – Experiment - Overview • Experimental High Energy Physics (6 teaching faculty) • Hadron Collider Physics • D0 at Fermilab: Hadron Collider Physics with Tevatron • CMS at the CERN: Hadron Collider Physics with LHC • B Physics • BaBar at SLAC: B Physics with PEP II e+e- collider • Experimental Nuclear Physics (4 teaching faculty) • QCD structure of nucleons/light nuclei • Parity violation at Jefferson Lab (G0) • nucleon form factors (elastic, transition, in medium) • Hypernuclei Theme Group 2
Theme Group 2 – Experiment (cont) • Particle Astrophysics (3 teaching faculty) • Milagro – Gamma Ray Astronomy at Los Alamos • IceCube – Neutrino Astronomy at the South Pole • Cosmic Ray Physics (1 teaching faculty) • CREAM – Balloon borne calorimeter measuring CR composition • ATIC (Advanced Thin Ionization Calorimeter) Balloon Experiment • BESS (Balloon borne Experiment with solenoid Spectrometer) • AMS (Alpha Magnet Spectrometer) on the Int. Space Station • Experimental Gravity (1 teaching faculty) • Sub-millimeter test of the inverse-square law • Gravitational wave experiment • Quantum Electronics (1 teaching faculty) • Fundamental Experiments with Lasers and Atomic Clocks • Theoretical Investigations of Curved Spacetime Gravitation Theme Group 2
High Energy Physics (HEP) • Experimental Particle Physics (High Energy Physics) • B Physics • BaBar at SLAC • CP Violation in B sector • Measurements of the CKM matrix elements • Search for Physics beyond the SM using rare decays • Hadron Collider Physics • D0 at Fermilab: • Top quark • W and Z mass and width • QCD and Substructure, SUSY, Extra Dimensions • CMS at the LHC • Electroweak Symmetry Breaking: the Higgs sector • SUSY • Extra Dimensions or Substructure or Mini Black Holes Theme Group 2
High Energy Physics: Personnel • Faculty • Drew Baden – Professor (DZero, CMS) (Fellow APS/DPF) • Sarah Eno – Associate Professor (DZero, CMS) • Nick Hadley – Professor (DZero, CMS) (Fellow APS/DPF) • Hassan Jawahery – Professor (BaBar) (Fellow APS/DPF) • Doug Roberts – Associate Professor (BaBar) • Andris Skuja– Professor (CMS, OPAL) (Fellow APS/DPF) • Chung Y. Chang – Professor Emeritus (OPAL) (Fellow APS/DPF) • Richard Kellogg – Senior Research Scientist (CMS, OPAL) • Shuichi Kunori – Associate Research Scientist (DZero, CMS) Theme Group 2
High Energy Physics Personnel • Post-Docs (7) • Chunhui Chen (BaBar) • Wouter Hulsbergen (BaBar) • Jeremy Mans (DZero, CMS) • Michiel Sanders (DZero, CMS) • Gabriele Simi (BaBar) • Terry Toole (DZero) • Marco Vercochi (DZero) • Graduate Students (7) • 3 BaBar Students • 4 DZero Students Theme Group 2
High Energy Physics – Personnel (cont) • Other Staff • 1½ Electronics Engineers • 1½ Administrative Assistants • Faculty History • Skuja – 1976 (E398, E253, E665, PLUTO, OPAL, SDC, CMS) • Jawahery – 1987 (CLEO 1.5, OPAL, BABAR) • Hadley – 1988 (DZero, SDC, CMS) • Baden – 1989 (DZero, SDC, CMS) • Eno – 1993 (DZero, CMS) • Roberts – 1997 (BABAR) Theme Group 2
BaBar Experiment at SLAC • Maryland group is one of the founding Institutions of BaBar (1993) • Faculty: Jawahery and Roberts • Primary goals: Study CP violation in B decays; Test the Standard Model Mechanism for CP violation(The CKM Matrix) and Search for Physics Beyond the SM Theme Group 2
BaBar Experiment at SLAC (cont) Group leadership on the BaBar Detector: Tracking • Co-system manager of Silicon Vertex Tracker • Co-leader of Silicon Alignment Calibration effort • Coordinator of BaBar Detector Control System & Drift Chamber Controls • Coordinator of the BaBar track reconstruction software System • Coordinator of the BaBar Vertex reconstruction Software Theme Group 2
BaBar Experiment at SLAC (cont) Group leadership on Physics: • Physics Analysis Coordinator of the experiment 2001-2002 • Convener of Hadronic Beauty and Charm decays (2000-2001) • Leading group in measurements of CKM phase alpha and direct CP violation from 2-body charmless B decays (Test of CKM Unitarity) • Leading group in measurement of CP violation effects in B decays in double charm final states (Search for deviation from SM) • Leading group in measurements of Time-Dependent CP violation in Radiative B decays b->s g(Search for deviation from SM) • Elected member of BaBar Executive Board • One of three from US universities Theme Group 2
HEP - Dzero Experiment at Fermilab • Maryland group joined in 1985 • Baden, Eno, Hadley, Kunori • Tevatron is the world’s current highest energy machine • Group tradition of leadership • First physics paper • New phenomena physics group co-leader twice • Top physics group co-leader at time of discovery • Overall Physics Convenor • Co-head of Monte Carlo group • Co-head of Computing and Software (twice) • Co-head of electroweak physics group • Electronics/trigger hardware Theme Group 2
HEP - Dzero Experiment at Fermilab (cont) • Group leadership (cont) • SUSY searches • Triggermeister (twice) • Institutional Board chair • Current Projects • W Mass and Width • Key measurement • Z Rapidity • MC co-leader • Gradual shift to CMS and LHC Theme Group 2
HEP - CMS at the LHC • Maryland Group joined CMS in 1994 • Leadership role in CMS Hadron Calorimeter (HCAL) Construction Installation and Commissioning • CMS HCAL Institutional Board Chair (Skuja) • US Project Manager of HCAL Construction and M&O (Skuja) • Engineering Design of HCAL Barrel (Skuja + engineers) • Design, Construction and Commissioning of Trigger/DAQ Electronics (Baden) • CERN Installation and Commissioning (Kellogg) • Physics of Jets and Missing Transverse Energy • Head of Jets/Mets PRS group (2000 to 2003) (Eno) • Head of LHC Physics Center at FNAL (Eno) • CMS Computing • HCAL/CMS Data Base project (Kunori) Theme Group 2
HEP - CMS HB Prof. Skuja is US HCAL Project Manager Both HCAL half-barrels are complete and in their alcove positions at the CMS surface hall (SX5). Electronics is being installed on the detector. After a burn-in period, integration operations will begin and continue until the CMS magnet test at the end of 2005. The Calorimeter will be lowered into UX5 in mid 2006. Theme Group 2
Fibers HEP – CMS/HCAL Electronics • Everything after digitization and before raw data collection and triggering • Primary functions: • Receiver cards for serial fiber input and deserialization • Maintain 40MHz data pipeline • Transmit to Level 1 Trigger system for decision • Concentrate accepted events • Monitoring system status, errors, etc. • Deliver luminosity calculation • To LHC machine for beam tuning • For physics analysis (sensitivity) CMS Hadron Calorimeter CPU Farm Trigger/DAQ PCI Analog Signals Digitize Level 1 Trigger Theme Group 2
High Energy Physics • Awards and Recognition (in addition to positions on experiments) • Baden • APS Fellow 2005 • SSC Fellowship 1991 • Associate Chair for Facilities and Personnel 1999-present • Eno • DOE Outstanding Junior Investigator Award (OJI) 1994-1999 • Executive Committee of the Division of Particles and Fields APS 2005-present • Hadley • APS Fellow 1997 • Secretary-Treasurer of the Division of Particles and Fields of APS 2001-2003 • Served as member Program Advisory Committees BNL, Cornell, Fnal • Chair, Fermilab Users Executive Committee 1994-1995 • Jawahery • APS Fellow 2005 • Associate Editor of Annual Review of Nuclear and Particle Science • Member: Particle Data Group (B Physics) • Roberts • Associate Chair for Undergraduate Education 2004-present • Skuja • APS Fellow 1998 Theme Group 2
High Energy Physics • Funding • DOE Group grant, $1.5M/year • CMS funding for both construction and M&O (maintenance and operations) $2.2M over last 3 years, one-time construction funding • Limiting Issues • Lack of University funded support for well-established mainstream groups • No matching resources for CMS Tier2 proposal • Difficult to start new efforts due to lack of suitable infrastructure • Quality/Quantity of space • Computing space is limited • Post-doc, Grad Student & Visitor space is tight • Department sequestered 1100 sq.ft. of lab space from HEP • Puts limits on immediate new initiatives Theme Group 2
High Energy Physics • Collaborations • Babar • 600 Physicists • SLAC • DZero Collaboration • 600 Physicists • Fermilab • CMS • Multinational effort of about 1B CHF (20% from US) • 1500 Physicists and Engineers (20% from US) • CERN • Data taking begins in late 2007 Theme Group 2
Experimental Nuclear Physics • Faculty (continuing) • Elizabeth Beise – Professor (G0) • James Kelly – Professor (nucleon form factors) • Herbert Breuer – Associate Research Scientist (G0) • Faculty (retiring July, 2005) • Chia-Cheh (George) Chang – Professor (hypernuclei) • Philip Roos – Professor (G0) • Post-Docs • Fatiha Benmokhtar (G0) Theme Group 2
Experimental Nuclear Physics • Graduate Students • 2 G0 • 1 pion form factor • Other Staff • 1/2 administrative assistant • Faculty History • Roos – 1967-2005 • Chant – 1972-2002 (now assoc. chair grad prog.) • Chang – 1974-2005 • Kelly – 1984 • Beise – 1993 • Current search for fall 2005 Theme Group 2
ENP recent students & postdocs Postdocs (since 95) F. Duncan (staff SNOLAB) A. Lung (asst. director, JLab) M. Jones (JLab staff) L. Ewell (medical physics) D. Brown P. King (postdoc, Illinois) F. Benmokhtar (current) Undergraduates (98-05) D. McGreggor C. Innes A. Yagi J. Stone L. Clevenger T. Horn D. Badiei-Boushehri A. Chen A. Cortes M.-C. Herda R. Ott L. West T. Brandt P. Clore *A. Parker *K. Kiriluk *K. Rossato *E. Andrade * current PhD students 98-05 R. Mohring (scientist, Millenniumcell) K. Gustafsson (Finnish Patent Bureau) D. Spayde (Grinnell College) N. Savvinov (postdoc, Bern) current: Tanja Horn, Jianglai Liu, Colleen Ellis (also supported 3 international students) Theme Group 2
Nuclear Physics - Research Program • QCD structure of matter • Polarized electron scattering at JLab • Parity violation + hadron structure • Nucleon Form Factors (elastic, transition) • pion charge distribution • hypernuclei G0 spectrometer in Hall C at JLab Neutron polarimeter for GEn Theme Group 2
Parity Violation and Strange Quarks (past) • Strange quarks unique window into nucleon’s quark-antiquark sea • directly accessible through weak interaction, use parity nonconservation 5% contribution SAMPLE: first measurement of s-quark contribution to proton’s magnetic moment (Spayde, Beise, et al Phys Lett B 2004) First determination of proton’s anapole structure (e-quark axial couplings) Theme Group 2
Parity Violation and Strange Quarks (present) • G0 Experiment at JLab • Provide spatial map of s-quark contributions to charge/magnetism over wide Q2 range. • Phase I completed 2004 • Phase II 2006-8 Roos: deputy spokesperson Beise: computation mgr, controls for liquid hydrogen target, luminosity det. Breuer: major role in detector construction and commissioning Postdocs: leading efforts in DAQ/analysis grads/undergrads involved in various aspects of construction, R&D Theme Group 2
Nucleon Elastic Form Factors • Renaissance using polarization methods • proton charge broader than magnetization • first precise data for GEn • UMd role in GEn @ JLab • Savvinov: thesis on pol. d • Kelly: led recoil pol. analysis • Future Directions • larger Q2, higher resolution • proton: onset of scaling sensitive to L • neutron: sensitive to deformation • Kelly: co-spokesperson for neutron recoil polarization Theme Group 2
Nucleon Transition Form Factors Kelly: co-spokesperson, physics analyses • Recoil polarization • sensitive to phase between resonant and nonresonant (dashed) contributions • angular distribution multipole analysis • minimal model dependence Theme Group 2
Experimental Nuclear Physics • Funding • current NSF grant: 1.5 M$ for 2002-2005 • pending NSF proposal: 1.7 M$ for 2005-2008 • Future plans • hire assistant professor in new research area, e.g. neutrino physics, fundamental symmetries, QCD • strong applicant pool! • complete G0 program • extend GEn to higher Q2 • transition from JLab to new area (s) Theme Group 2
Experimental Nuclear Physics • Awards, Recognition, and Science Community Service • Beise • APS Fellow 2001 • Nuclear Science Adv. Comm (NSAC) 1999-2001 • DNP committees (Exec., Program, Summer School,…) • NSF Young Investigator Award 1995-99 • Maria Goeppert-Mayer Award 1998 • APS Centennial Speaker 1998-99 • Assoc. Editor Nucl. Phys. A 1999- • Phys. Rev. C Editorial Board 2005- • NSF Program Director for Nuclear Physics, 2004- • Kelly • J. Robert Oppenheimer Fellowship (1983-4) • LANL PACs • Roos • APS Fellow 1985 • NSAC membership • NSF program director for Nuclear Physics 1993-95 • DNP committees • LANL, IUCF PACs Theme Group 2
Experimental Nuclear Physics • Limiting Issues • Aging faculty • Has limited our ability to move to new areas • two retirements imminent; 1 search in progress • space • protracted recovery from fire/move, impacted our ability to take on new hardware projects • New laboratory now complete (lost meeting space) • Shop charges • Hard to compete for big hardware projects Theme Group 2
Particle Astrophysics • Faculty • Jordan Goodman – Professor (Ice3, Milagro) • Kara Hoffman – Assistant Professor (Ice3) • Greg Sullivan – Associate Professor (Ice3, Milagro) • Andrew Smith – Assistant Research Scientist (Milagro) • Tyce DeYoung – Assistant Research Scientist (Ice3) • Erik Blaufuss - Assistant Research Scientist (Ice3) • Robert Ellsworth – Visiting Professor (GMU) (Ice3, Milagro) • David Berley – Visiting Professor (Ice3, Milagro) • Post-Docs • Curtis Lansdell (Milagro) • Alex Olivas (Ice3) • Dusan Turcan (Ice3) • TBH (Ice3) Theme Group 2
Particle Astrophysics • Graduate Students • 3 IceCube Students (adding a 4th) • 2 Milagro Students • Other Staff • 3 software/computer support (2.5 Ice3, .5 Milagro) • 1 administrative assistant • Faculty History • Goodman – 1980 • Sullivan – 1995 • Hoffman – 2004 Theme Group 2
Particle Astrophysics - Research Program • IceCube • Neutrino Astrophysics • Status • Maryland’s role (16 people) • Milagro • GRBs • Diffuse Sources • Maryland’s role (8 people) • Super-Kamiokande • Neutrino Oscillations • Phased out in ’03-’04 as Ice3 ramped up Theme Group 2
Particle Astrophysics - Research Program • IceCube • Neutrino Telescope of 1km3 instrumented volume • Detect neutrinos of 100 GeV – 1021 eV • Astrophysical neutrino sources • AGN, GRB, Diffuse (Cosmic Ray origins) • WIMP searches, neutrino oscillation studies • MRE approved and 1st construction season complete • Set up and operated the Hot Water Drill • Drilled to design (2450m depth) • Deployed first String • All DOMs functioning and being read out • Planning and production for full construction. Theme Group 2
Particle Astrophysics - Research Program • IceCube (cont’d) • 1st String • Maryland’s Role • Major role in the scientific and project leadership • 16 scientific staff (2nd largest), L2 and L3 managers • Responsibilities in Online filtering, Offline software systems, simulation, reconstruction, deployment … Theme Group 2
Particle Astrophysics - Research Program • Milagro • Gamma Ray Observatory • All sky ~1 TeV gamma-ray observatory in New Mexico • AGN, GRB flaring TeV sources, extended TeV sources, Galactic TeV sources 1 TeV g-ray • High energy (~1 TeV) gamma-rays interact in the top of the atmosphere • A shower of secondary particles is developed in the atmosphere • A shower-front of the particles hit the ground & is detected in Milagro • The relative arrival times of the shower-front determines the direction of the original 1 TeV gamma-ray. Milagro Pond Theme Group 2
Particle Astrophysics - Research Program • Milagro (cont’d) • Results • Maryland’s Role • Goodman is Spokesperson • Lead Institution Milagrito GRB 970417a MRK 501 MRK 421 Flare Inner galaxy CRAB Theme Group 2
Particle Astrophysics • Funding • Milagro Funding • $1.7M detector operations funding from NSF (’04-’07) • $1.4M NSF grant funding for UM (’03-’06) • IceCube Funding • $240M MRE Project funding from the NSF administered through the U of Wisconsin • Maryland is 2nd largest University group • $1.2M - $1.5M per year project funding for personnel. Equipment varies by construction year. • $1.2M NSF grant renewal pending ’05-’08 Theme Group 2
Particle Astrophysics • Collaborations • Milagro Collaboration • 35 Physicists • Los Alamos National Lab • UC Irvine, UC Santa Cruz, GMU, NYU, MSU, UNH • IceCube • 100+ Physicists • Wisconsin, UM, UCB, PSU, LBNL … • NSF/Raytheon Polar Programs • Germany, Sweden, Belgium, UK, Japan, NZ … Theme Group 2
Particle Astrophysics • Awards and Recognition • Goodman • APS Fellow • Richtmyer Memorial Lecture Award – AAPT • Kirwan Award – UM • Distinguished Scholar Teacher – UM • Sullivan • Ferrell Fellowship – UM • SSC Fellowship Theme Group 2
Particle Astrophysics • Limiting Issues • Quality/Quantity of space issues • Computing space • Post-doc, Grad student & programmer space • Meeting space Theme Group 2
Cosmic Ray Physics 0 http://cosmicray.umd.edu/homepage • Faculty • Eun-Suk Seo (UMD 1991), Assoc. Professor (BESS, ATIC, CREAM, AMS) • Opher Ganel (UMD 1997), Assis. Research Scientist (ATIC, CREAM) • Vladimir Ptuskin, Visiting Research Scientist, IZMIRAN Moscow, (Theory) • Post-Docs (5) • Moo Hyun Lee (BESS, CREAM) • Alexander Malinin (AMS) • Ramin Sina (Theory) • Hoseok Ahn (ATIC, CREAM) • Sonny Zinn (BESS, CREAM) • Graduate Students (9) • 7 CREAM Students • 1 BESS Student • 1 ATIC Student • Undergraduate Student • 1 computer system manager • Other Staff • 1 faculty research assistant for software, 1 electrical engineer Theme Group 2
Cosmic Ray Physics - Research Program 0 • This group’s research employs satellite and balloon-borne instruments to make direct measurements of cosmic ray particles from space over more than seven orders of magnitude of the cosmic-ray energy spectrum. • Research projects address three basic themes: • Searches for exotic matter such as antimatter and dark matter; • Precise measurements of galactic cosmic rays in the energy range where they are most abundant (~108 to ~1012 eV) to understand their origin, acceleration, and propagation; and • Precise measurements with large aperture instruments at higher energies (~1012 to ~1015 eV) where the fluxes are extremely low, in order to explore the limit of supernova shock wave acceleration. BESS ATIC CREAM AMS ground based Seo Group Space Physics P-Astro Group Theme Group 2
Cosmic Ray Physics - Research Program • CREAM (Cosmic Ray Energetics And Mass) Balloon Experiment • Explore supernova acceleration limit, Understanding of cosmic ray propagation history, extends ATIC measurements to higher energies • First flight set a new duration record of 42 days; CREAM-II under construction • Maryland’s role: overall management of the mission as PI, design and construction of the calorimeter module and common electronics including master trigger, command, power, flight software etc. • ATIC (Advanced Thin Ionization Calorimeter) Balloon Experiment • High energy composition; fill the data gap in the TeV energy region • 16-day flight in 2000, 20-day flight in 2002, planned for Dec. 2005 flight • Maryland’s role: Detector design, Monte Carlo simulations, Data processing, distribution and analysis (UMD produces official data sets) • BESS (Balloon borne Experiment with Superconducting solenoid Spectrometer) • Antimatter/Dark matter Search • Annual 1-day flights 1993-2003, 8.5-day flight in 2004; best antiproton spectra • Maryland’s role: Time-of-Flight counter assembly/test, data analysis particularly spectral analysis of proton & He including isotopes • AMS (Alpha Magnet Spectrometer) on the International Space Station • Antimatter/Dark matter Search • Scheduled for Jan 2008 launch; the largest magnet spectrometer in space • Maryland’s role: Simulations,Ring Imaging Cherenkov counter Development, • AMS-01 (Shuttle flight 1998) - Data interpretation Theme Group 2
Cosmic Ray Physics - Research Program 0 • This group’s precision measurements fill the gap between the space and ground based research activities of other groups on campus. • The ATIC, BESS, and CREAM balloon-borne instruments are based on particle detectors like those used at accelerators, but the payloads are like large space experiments. • The instruments are for the most part built in-house by students and young scientists, many of them currently working in the on-campus laboratory. • The CREAM Science Operation Center at UMD remotely controls the instruments in flight by sending commands and receiving data via satellite. • This group has a unique strength of having all the data from ATIC, BESS and CREAM, which cover 7 decades in energy 108 – 1015 eV. Theme Group 2
Cosmic Ray Physics - Funding Currently ~ $1.5 M/yr from NASA & NSF Funding ($) Theme Group 2
Cosmic Ray Physics - Collaborations • CREAM • ~40 Physicists • U of Chicago, PSU, OSU, UMN; INFN-Pisa, Siena, Italy; LPSC-Grenoble France; EWU-Seoul, KPNU-Taegu, KAIST-Taejon, Korea • ATIC • ~25 Physicists • LSU, NASA MSFC; MSU-Moscow, Russia; MPI-Lindau, Germany • BESS • ~50 Physicists • NASA GSFC; KEK-Tsukuba, Tokyo U, Kobe U, ISAS, Japan • AMS • ~350 Physicists • MIT, Yale,....; INFN-Bologna, Italy; LPSC-Grenoble, France; CIEMAT- Madrid, Spain; LIP-Lisbon, Portugal etc. * Also work with CERN for beam tests; NASA GSFC Wallops Flight Facility, National Scientific Balloon Facility, NSF Office of Polar Programs, and Raytheon Polar Services Company for Antarctic balloon flights; and contractors including Swales Aerospace. Theme Group 2
Cosmic Ray Physics - Awards and Recognition 0 • Seo received a Presidential Early Career Award for Scientists and Engineers in 1997 • The record breaking flight of CREAM in 2004 got international media coverage following NASA press release : • NASA press release #05-031(1/28/05), “NASA research balloon makes record-breaking flight” • SpaceRef.com • SpaceFlight Now • Live Science • New Scientist • Space Daily • PhysOrg.com • Unexplainable.net • Technocrat.net • WESR Radio • Chosun Daily • The Antarctic Sun Theme Group 2
Cosmic Ray Physics - Limiting Issues 0 • Quality/Quantity of space issues • Internet speed • Bottle neck of 10 Mbps between offices severely limits Science Operation Center’s efficiency. • Lab • Environment control (temperature, humidity...) • Maintenance (leaky ceiling, cleaning frequency...) • No high bay lab for payload integration • Location of the group • Distance from physics building limits interactions Theme Group 2
Gravity Experiment • Experiments • Submillimeter test of the inverse-square law (ISL) • Gravitational wave experiment (GW) • Applications of superconducting gravity gradiometer (SGG) • Faculty • Ho Jung Paik – Professor (ISL, GW, SGG) • M. Vol Moody – Associate Research Scientist (ISL, SGG) • Graduate Students • 1 ISL Student • 1 GW Student • Other Staff • 1 electronics/computer support • 1 mechanical engineer • Faculty History • Paik – 1978 Theme Group 2
Gravity Experiment - Research Program • ISL test • Gauss’s law test at 1 m (1980-1993): • 1/r2 law 2 = 4G. • Detector: 3-axis SGG (2 = 0?) • 2 10-4 (best limit at 1 m) • New null test at 100 m (2002- ): • Source: plane slab, detector: 1-axis SGG. • 1/r2 law = const outside of the slab. • Will probe extra dimensions to < 10 m. Gauss’s Law Detector Moody & Paik, PRL (1993) Theme Group 2