Final Thoughts and Highlights Barry C. Barish Caltech Amaldi-6 Okinawa 24-June -05 LISA

24-June-05Amaldi-6 - Barish2 Towards Detection of Gravitational Waves  From LISA Concept Demonstrations Mission  From Bars Bars with Increased Bandwidth Spheres  From Interferometers Advanced Interferometers Next Generation (QND) Detectors  From 8 Mpc (NN inspiral) 200 Mpc and then beyond  From Upper Limits Searches Detections  From Generic Searches Searches with Specified Waveforms  From Single Detectors Global Networks

24-June-05Amaldi-6 - Barish3 Gravitational Waves in Space LISA Three spacecraft, each with a Y-shaped payload, form an equilateral triangle with sides 5 million km in length.

24-June-05Amaldi-6 - Barish4 LISA

24-June-05Amaldi-6 - Barish5 LISA

24-June-05Amaldi-6 - Barish6 LISA

24-June-05Amaldi-6 - Barish7 Total number of detatched binaries Total number of interacting binaries Distribution of WD binaries (Nelemans et al) WD-WD, WD-NS, NS-NS binaries with GW frequency within LISA band are observed. These sources are GUARANTEED Krolak

24-June-05Amaldi-6 - Barish8 Data Analysis Issues Stochastic signal Isolated signals Interacting signals Long wavelength regimeShort wavelength regime TDI LISA motion; long observation times; network of detectors Krolak

24-June-05Amaldi-6 - Barish9 LISA

24-June-05Amaldi-6 - Barish10 LISA The diagram shows the sensitivity bands for LISA and LIGO

24-June-05Amaldi-6 - Barish11 DECIGO Bridges the Gap Frequency [Hz] Strain [Hz - 1/2 ] LISA DECIGO Terrestrial Detectors (e.g. LCGT) The Japanese Space Gravitational Wave Antenna - DECIGO Deci-hertz Interferometer Gravitational Wave Observatory

24-June-05Amaldi-6 - Barish12 Sensitivity of DECIGO Force noise= 1/100 of LISA’s

24-June-05Amaldi-6 - Barish13 Explorer Switzerland Allegro USA Schenberg Brazil MiniGrail The Netherlands Niobe Australia Nautilus, italy Auriga, Italy Resonant Bar Detectors

24-June-05Amaldi-6 - Barish14

24-June-05Amaldi-6 - Barish15 “spheres” omnidirectionality: decode the excitation of the 5 quadrupolar modes to get uniform sky coverage & find direction of propagation cross section: larger as the volume fill-up factor in respect to bars MiniGRAIL (Leiden-Rome) just started operation Talks of Annette de Waard and Luciano Gottardi Schenberg (Brasil) coming to

sensitive in a few kHz-wide freq band !!! GW signals add back action noises subtract read-out with non-resonating transducers the differential deformations at frequencies between the lowest quadrupolar modes DUAL: two nested resonant masses Cerdonio et al PRL (2001), Bryant et al PRD (2003), Bonaldi et al PRD (2003) talk by Michele Bignotto

24-June-05Amaldi-6 - Barish17 sensitivities in the prospective

Bar Network

24-June-05Amaldi-6 - Barish19 International Gravitational Event Collaboration (IGEC)  ALLEGRO,AURIGA,EXPLORER, NAUTILUS, and NIOBE  The search for burst waves at resonant frequency ~ 900 Hz.  The detectors nearly parallel to maximize coincident sensitivity.  Candidate events at SNR > 3-5 (~ background events 100/day)  Data exchanged: peak amplitude, time of event and uncertainties.  Threshold equivalent to ~0.1 M ⊙ converted into a gravitational wave millisecond burst at a distance of 10 kpc.  The accidental coincidence rate over 1 sec interval (e.g. bandwidth of 1 Hz) was ~ few/week two-fold and ~few/century three-fold.  Time resolution not sufficient to resolve incident wave direction, no directional search has been applied.  No evidence for grav wave bursts was found.

24-June-05Amaldi-6 - Barish20 rate [y –1 ] search threshold h h ~  E ~ 0.02 M ⊙ 10 kpc Upper Limit on the Rate of gravitational waves bursts from the GALACTIC CENTER random arrival times and amplitude  search threshold h The Area above the blue curve is excluded with a coverage > 90% [ P. Astone, et al. Phys. Rev. D68 (2003) ] IGEC coincidence search Final results

24-June-05Amaldi-6 - Barish21 During 2001 EXPLORER and NAUTILUS were the only two operating resonant detectors, with the best ever reached sensitivity. An algorithm based on energy compatibility of the event was applied to reduce the “background” EXPLORER-NAUTILUS 2001 Sidereal hours Number of events ROG Coll.: CQG 19, 5449 (2002) L.S.Finn: CQG 20, L37 (2003) P.Astone, G.D’Agostini, S.D’Antonio: CQG Proc. Of GWDAW 2002, gr-qc/ E. Coccia ROG Coll.:CQG Proc. Of GWDAW 2002 ROG Coll.: gr-qc/ New data needed Excess ??? Direction of Galactic Disc

24-June-05Amaldi-6 - Barish22 ROG S 03 ROG S 01 suggestion - crewless operation - data validated by cosmic ray effect - new upper limit with bars, no significant coincidence excess nor sidereal effect. EXPLORER NAUTILUS Science Run 03

24-June-05Amaldi-6 - Barish23 IGEC-2 Expected Performance Triple coincidences: 10 6 time shifts, no accidentals, 9.3 days false alarm rate /Hz Double coincidences: lower false alarm rates than for IGEC-1 rate [year –1 ] search threshold dashed region excluded with probability > 90% My best guess on the achievable upper limit improvement by IGEC-2 WARNING: incomplete data set ! 1 month 1 year IGEC-1 upper limit

24-June-05Amaldi-6 - Barish24 Interferometer Detectors LIGO Louisiana 4000m TAMA Japan 300m Virgo Italy 3000m GEO Germany 600m AIGO Australia future LIGO Washington 2000m & 4000m

24-June-05Amaldi-6 - Barish25 TAMA Kanda

24-June-05Amaldi-6 - Barish26 TAMA Kanda

24-June-05Amaldi-6 - Barish27 S4 Sensitivity

24-June-05Amaldi-6 - Barish28 Noise Progression of the Louisiana Interferometer

24-June-05Amaldi-6 - Barish29 Results for Neutron Star Binaries  Event Candidates »142 event candidates found in the data »Loudest candidates eliminated in follow up investigation… »Other candidates consistent with background of analysis pipeline  Upper limit set on the rate of BNS coalescences R 90 = 47 / year / MWEG

24-June-05Amaldi-6 - Barish30 Results for Primordial Black Hole Binaries  Same analysis pipeline  Event rate consistent with background of analysis pipeline  Upper limit set on the rate of PBHB coalescences R 90 = 63 / year / MWEG

24-June-05Amaldi-6 - Barish Log( f [Hz]) Log (W 0 h ) f ~ H 0 - one oscillation in the lifetime of the universe f ~ 1/Plank scale – red shifted from the Plank era to the present time Laser Interferometer Space Antenna - LISA Inflation Slow-roll Cosmic strings Pre-big bang model EW or SUSY Phase transition Cyclic model CMB Pulsar Nucleosynthesis LIGO band Stochastic Background Predictions and Experimental Limits LIGO S1, 2 wk data Ω 0 h < 23 PRD 69(2004) (H2-L1) Advanced LIGO, 1 yr data Expected Ω 0 h < 7x ( H1-L1) LIGO S3, 2 month data Ω 0 h < 4.4x10 -4 (H1-L1) presented here Initial LIGO, 1 yr data Expected Ω 0 h < 2x10 -6 (H1-L1)

24-June-05Amaldi-6 - Barish32 Conclusions  Sensitivity toward gravitational wave detection is improving on many fronts and this will continue well into the future  New upper limits are being set for the major sources -- binary inspirals, periodic sources, burst sources and stochastic background.  Data exchange and joint data analysis between detector groups is improving our ability to make detections  Many exciting future projects and upgrades are planned or getting underway.  Hopefully, detections will be made soon !! Maybe by Amaldi-7??

24-June-05Amaldi-6 - Barish33 THANKS Amaldi-6 Organizers!!! See at Amaldi-7 Sydney