Barry C. Barish Caltech Laboratoire de L’Accelerateur Lineaire 26- April-11  Physics & Gravitational Waves & International Linear Collider

Michel Davier and  physics * Pioneer in the field * * Atlas/BaBar precision studies *

26-April-11Davier - Prix Andre Lagarrique3

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Michel Davier and gravitational waves * Pioneer in the field * * Burst sources - detection* Supernova “burst” detection 1999 Gamma ray “burst” detection 2010

Einstein’s Theory of Gravitation gravitational waves Using Minkowski metric, the information about space-time curvature is contained in the metric as an added term, h mn. In the weak field limit, the equation can be described with linear equations. If the choice of gauge is the transverse traceless gauge the formulation becomes a familiar wave equation The strain h mn takes the form of a plane wave propagating at the speed of light (c). Since gravity is spin 2, the waves have two components, but rotated by 45 0 instead of 90 0 from each other. 26-April-11Davier - Prix Andre Lagarrique7

The evidence for gravitational waves Hulse & Taylor   17 / sec Neutron binary system separation = 10 6 miles m 1 = 1.4m  m 2 = 1.36m  e = period ~ 8 hr PSR Timing of pulsars Prediction from general relativity spiral in by 3 mm/orbit rate of change orbital period 26-April-11Davier - Prix Andre Lagarrique8

“Indirect” evidence for gravitational waves 26-April-11Davier - Prix Andre Lagarrique9

Frequency range of GW Astronomy Audio band SpaceTerrestrial Electromagnetic waves  over ~16 orders of magnitude  Ultra Low Frequency radio waves to high energy gamma rays Gravitational waves  over ~8 orders of magnitude  Terrestrial + space detectors 26-April-11Davier - Prix Andre Lagarrique10

Ground based interferometers LIGO 4 km LIGO 4 km & 2 km VIRGO 3 km TAMA 300m GEO 600m Simultaneous detection Detection confidence Source polarization Sky location Duty cycle Verify light speed propagation Waveform extraction AIGO- R&D facility 26-April-11Davier - Prix Andre Lagarrique11

Event Localization: Array of GW Interferometers SOURCE LIGO Livingston LIGO Hanford TAMA GEO VIRGO  12  L =  t/c cos  =  t / (c D 12 )  ~ 0.5 deg D 26-April-11Davier - Prix Andre Lagarrique12

Astrophysical Sources signatures  Compact binary inspiral: “chirps” »NS-NS waveforms are well described »BH-BH need better waveforms »search technique: matched templates  Supernovae / GRBs: “bursts” »burst signals in coincidence with signals in electromagnetic radiation »prompt alarm (~ one hour) with neutrino detectors  Pulsars in our galaxy: “periodic” »search for observed neutron stars (frequency, doppler shift) »all sky search (computing challenge) »r-modes  Cosmological Signal “stochastic background” 26-April-11Davier - Prix Andre Lagarrique13

GW Bursts from core collapse supernova  Within about 0.1 second, the core collapses and gravitational waves are emitted.  After about 0.5 second, the collapsing envelope interacts with the outward shock. Neutrinos are emitted.  Within 2 hours, the envelope of the star is explosively ejected. When the photons reach the surface of the star, it brightens by a factor of 100 million.  Over a period of months, the expanding remnant emits X-rays, visible light and radio waves in a decreasing fashion. Gravitational waves April-11Davier - Prix Andre Lagarrique14

Michel Davier and the ILC * Pioneer in the field* * IDAG Chair *

26-April-11 Davier - Prix Andre Lagarrique SPEAR PETRA LEP ENERGY YEAR TeV ILC GeV Fourth generation? Three Generations of Successful e + e - Colliders The Energy Frontier 16

Exploring the Terascale The Tools  The LHC »It will lead the way and has large reach »Quark-quark, quark-gluon and gluon-gluon collisions at TeV »Broadband initial state  The ILC »A second view with high precision »Electron-positron collisions with fixed energies, adjustable between 0.1 and 1.0 TeV »Well defined initial state  Together, these are our tools for the Terascale Davier - Prix Andre Lagarrique26-April-1117

26-April-11 Davier - Prix Andre Lagarrique LHC ILC e + e –  Z H Z  e + e –, H  b … Higgs event Simulation Comparison 18

26-April-11 Davier - Prix Andre Lagarrique Higgs Signal with LHC  Rare decay channel: BR~10 -3  Projected signal and background after data cuts to optimize signal to background  Background large: S/B  1:20, but can estimate from non signal areas CMS 19

26-April-11 Davier - Prix Andre Lagarrique Precision Higgs physics  Model-independent Studies mass absolute branching ratios total width spin top Yukawa coupling self coupling  Precision Measurements Garcia-Abia et al 20

Designing a Linear Collider Superconducting RF Main Linac 26-April-11Davier - Prix Andre Lagarrique21

ILC Baseline Design Gev e+ e- Linear Collider Energy 250 Gev x 250 Gev Length km # of RF units 560 # of cryomodules1680 # of 9-cell cavities Detectors push-pull peak luminosity 5 Hz rep rate > 6000 bunches per cycle  x 350 – 620 nm;  y 3.5 – 9.0 nm 26-April-11Davier - Prix Andre Lagarrique22

26-April-11 Davier - Prix Andre Lagarrique Interaction Region (old location) Break point for push-pull disconnect Provide reliable collisions of 5nm-small beams, with acceptable level of background, and be able to rapidly and efficiently exchange ~10kT detectors in a push-pull operation several times per year 23

26-April-11 Davier - Prix Andre Lagarrique Detector Concepts Report 24

26-April-11 Davier - Prix Andre Lagarrique Detector Performance Goals 25

26-April-11 Davier - Prix Andre Lagarrique Detector Performance Goals 26

26-April-11 Davier - Prix Andre Lagarrique Detector Performance Goals  ILC detector performance requirements and comparison to the LHC detectors: ○ Inner vertex layer ~ 3-6 times closer to IP ○ Vertex pixel size ~ 30 times smaller ○ Vertex detector layer ~ 30 times thinner Impact param resolution Δd = 5 [μm] + 10 [μm] / (p[GeV] sin 3/2θ) ○ Material in the tracker ~ 30 times less ○ Track momentum resolution ~ 10 times better Momentum resolution Δp / p 2 = 5 x [GeV -1 ] central region Δp / p 2 = 3 x [GeV -1 ] forward region ○ Granularity of EM calorimeter ~ 200 times better Jet energy resolution ΔE jet / E jet = 0.3 /√E jet Forward Hermeticity down to θ = 5-10 [mrad] 27

26-April-11 Davier - Prix Andre Lagarrique International Detector Advisory Group IDAG – M Davier (Chair)  Four detector concepts developed for the Reference Design (2007)  How to move forward with R&D and design that focusses on what is needed to develop realistic detector concepts and techniques  Call for Letters of Intent that flesh out detector concepts toward these goals.  IDAG created to monitor and guide this process and ‘validate’ LOIs.  Two detector concepts validated, but success breeds more work and IDAG continues to closely guide this process under Michel’s leadership 28

26-April-11 Davier - Prix Andre Lagarrique Final Words for Michel My personal congratulations to a great physicist, a wonderful colleague and a good friend 29