LIGO-India Detecting Einstein’s Elusive Waves Opening a New Window to the Universe

1. LIGO-IndiaDetecting Einstein’s Elusive WavesOpening a New Window to the Universe IndIGO Consortium (Indian Initiative in Gravitational-wave Observations) An Indo-US joint mega-project concept proposal Version: 3 Jun 11, 2011 www.gw-indigo.org

2. Space Time as a fabric In 1916, Albert Einstein published his famous Theory of General Relativity, the theory of gravitation. 4-dimensional space-time (the normal three dimensions of space, plus a fourth dimension of time). His theory describes how space-time is affected by mass and also how mass affects spacetime. Matter tells spacetime how to curve, and spacetime tells matter how to move.

3. Space Time as a fabric

4. Einstein’s General theory of relativity • is the most • beautiful & successful • theory of modern physics. • It has matched all tests of Gravitation in the solar system (weak fields) remarkably well.

5. What happens when matter is in motion?

6. Einstein’s theory predicts Matter in motion fluctuation in the curvature of space-time which propagates as a wave Space-time ripples or gravitational waves

7. Binary Neutron stars Pulsar companion

8. GW from Binary Neutron stars

9. Indirect evidence for Gravity waves Nobel prize in 1993 !!! Hulse and Taylor Results for PSR1913+16 Binary pulsar emits gravitational waves leads to loss of orbital energy period speeds up 14 sec from 1975-94 measured to ~50 msec accuracy deviation grows quadratically with time

10. Effect of GW on test masses

11. Effect of GW on a ring of test masses Interferometer mirrors as test masses

12. Path A Path B Detecting GW with Laser Interferometer B A Difference in distance of Path A & B Interference of laser light at the detector (Photodiode)

13. Path difference  phase difference Equal arms: Dark fringe The effects of gravitational waves appear as a fluctuation in the phase differences between two orthogonal light paths of an interferometer. Unequal arm: Signal in PD

14. Challenge of Direct Detection Gravitational waves are very weak! Gravitational wave is measured in terms of strain,h (change in length/original length) Expected amplitude of GW signals Measure changes of one part in thousand-billion-billion!

15. A Century of Waiting • Almost 100 years since Einstein predicted GW but no direct experimental confirmation a la Hertz • Two Fundamental Difference between GR and EM - Weakness of Gravitation relative to EM (10^-39) -Spin two nature of Gravitation vs Spin one of EM that forbids dipole radiation in GR -Low efficiency for conversion of mechanical energy to GW. Feeble effects of GW on a Detector • GW Hertz expt ruled out. Only astrophysical systems involving huge masses and accelerating very strongly are potential sources of GW signals.

17. LIGO and Virgo TODAY Field reached a Milestone with decades-old plans to build and operate large interferometric GW detectors now realized at several locations worldwide Unprecedented sensitivity allows one to place Upper Limits on GW from a variety of Ap sources. Improve on Spindown of Crab, Vela pulsars, Big Bang nucleosynthesis bound on Stochastic GW..

18. Schematic Optical Design of Advanced LIGO detectors

20. Expected Annual Coalescence Rates In a 95% condence interval, rates uncertain by 3 orders of magnitude NS-NS (0.4 - 400); NS-BH (0.2 - 300) ; BH-BH (2 - 4000) yr^-1 Based on Extrapolations from observed Binary Pulsars,Stellar birth rate estimates, Population Synthesis models. Rates quoted below are mean of the distribution.

21. Era of Advanced LIGO detectors: 2015 • 10x sensitivity • 10x reach • 1000 volume • >> 1000 event rate • (will reach beyond nearest superclusters)

22. GEO: 0.6km VIRGO: 3km LIGO-LHO: 2km, 4km LCGT 4km TAMA/CLIO LIGO-LLO: 4km LIGO-Australia? GW Astronomy with Intl. Network of GW Observatories 1. Detection confidence 2. Duty cycle 3. Source direction 4. Polarization info. LIGO-India ?

23. GWIC: Gravitational Wave International Committee Courtesy: B. Schutz: GWIC Roadmap Document

24. Indo-Aus.Meeting, Delhi, Feb 2011

25. Gravitational wave Astronomy : • Synergy with other major Astronomy projects: • SKA: Radio : Pulsars timing, • X-ray satellite (AstroSAT) • Gamma ray observatory • Thirty meter telescope: gamma ray follow-up,… Courtesy: B. Schutz, GWIC Roadmap Document 2010

26. INDIGO:the goals • Major experimental science science initiative in GW astronomy • LIGO-India (Letter from LIGO Labs) • Advanced LIGO hardware for 1 detector to be shipped to India. • India provides suitable site and infrastructure to house the GW observatory • Site, two 4km armlength high vacuum tubes in L config. • Indian cost ~Rs 1000Cr • Earlier plan: Partnership in LIGO-Australia (a diminishing possibility) • Advanced LIGO hardware for 1 detector to be shipped to Australia at the Gingin site, near Perth. NSF approval • Australia and International partners find funds (equiv to half the detector cost ~$140M and 10 year running cost ~$60M) within a year. • Indian partnership at 15% of Australian cost with full data rights. • Consolidated IndIGO membership of LIGO Scientific Collaboration + propose creating a Tier-2 data centre for LSC in IUCAA + IUSSTF IndoUS joint Centre at IUCAA with Caltech (funded) • Provide a common umbrella to initiate and expand GW related experimental activity and training new manpower • 3m prototype detector in TIFR (funded). Unnikrishnan • Laser expt. RRCAT, IIT M, IIT K | High Vaccum & controls at RRCAT, IPR, BARC, ISRO, …. • UG summer internship at Natn. & Intl GW labs & observatories. • PostgradIndIGO schools, specialized courses,…

27. Multi-Institutional, Multi-disciplinary Consortium • CMI, Chennai • Delhi University • IISER Kolkata • IISER Trivandrum • IIT Madras • IIT Kanpur • IUCAA • RRCAT • TIFR • RRI • IPR, Bhatt • JamiaMiliaIslamia • TezpurUniv

28. The IndIGO Consortium IndIGO Council Bala Iyer ( Chair) RRI, Bangalore Sanjeev Dhurandhar (Science) IUCAA, Pune C. S. Unnikrishnan (Experiment) TIFR, Mumbai Tarun Souradeep (Spokesperson) IUCAA, Pune Data Analysis & Theory Sanjeev Dhurandhar IUCAA Bala Iyer RRI Tarun Souradeep IUCAA Anand Sengupta Delhi University Archana Pai IISER, Thiruvananthapuram Sanjit Mitra JPL , IUCAA K G Arun Chennai Math. Inst., Chennai Rajesh Nayak IISER, Kolkata A. Gopakumar TIFR, Mumbai T R Seshadri Delhi University Patrick Dasgupta Delhi University Sanjay Jhingan Jamila Milia Islamia, Delhi L. Sriramkumar, Phys., IIT M Bhim P. Sarma Tezpur Univ . P Ajith Caltech , USA Sukanta Bose, Wash. U., USA B. S. Sathyaprakash Cardiff University, UK Soumya Mohanty UTB, Brownsville , USA Badri Krishnan Max Planck AEI, Germany Instrumentation & Experiment C. S. Unnikrishnan TIFR, Mumbai G Rajalakshmi TIFR, Mumbai P.K. Gupta RRCAT, Indore Sendhil Raja RRCAT, Indore S.K. Shukla RRCAT, Indore Raja Rao ex RRCAT, Consultant Anil Prabhakar, EE, IIT M Pradeep Kumar, EE, IIT K Ajai Kumar IPR, Bhatt S.K. Bhatt IPR, Bhatt Ranjan Gupta IUCAA, Pune Rijuparna Chakraborty, Cote d’Azur, Grasse Rana Adhikari Caltech, USA Suresh Doravari Caltech, USA Biplab Bhawal (ex LIGO)

29. IndIGO Advisory Structure Committees: National Steering Committee: Kailash Rustagi (IIT, Mumbai) [Chair]Bala Iyer (RRI) [Coordinator]Sanjeev Dhurandhar (IUCAA) [Co-Coordinator]D.D. Bhawalkar (Quantalase, Indore)[Advisor] P.K. Kaw (IPR) Ajit Kembhavi (IUCAA) P.D. Gupta (RRCAT)J.V. Narlikar (IUCAA)G. Srinivasan International Advisory Committee Abhay Ashtekar (Penn SU)[ Chair] Rana Adhikari (LIGO, Caltech, USA) David Blair (AIGO, UWA, Australia)Adalberto Giazotto (Virgo, Italy)P.D. Gupta (Director, RRCAT, India)James Hough (GEO ; Glasgow, UK)[GWIC Chair]Kazuaki Kuroda (LCGT, Japan)Harald Lueck (GEO, Germany)Nary Man (Virgo, France)Jay Marx (LIGO, Director, USA)David McClelland (AIGO, ANU, Australia)Jesper Munch (Chair, ACIGA, Australia)B.S. Sathyaprakash (GEO, Cardiff Univ, UK)Bernard F. Schutz (GEO, Director AEI, Germany)Jean-Yves Vinet (Virgo, France)Stan Whitcomb (LIGO, Caltech, USA) Program Management committee C S Unnikrishnan (TIFR, Mumbai), Chair. Bala R Iyer (RRI, Bangalore), Coordinator Sanjeev Dhurandhar (IUCAA, Pune) Co-cordinator Tarun Souradeep (IUCAA, Pune) Bhal Chandra Joshi (NCRA, Pune) P Sreekumar (ISAC, Bangalore) P K Gupta (RRCAT, Indore) S K Shukla (RRCAT, Indore) Sendhil Raja (RRCAT, Indore) INSERT BOX

30. LIGO-Australia: Idea and Opportunity • The NSF approved grand decision to locate one of the planned LIGO-USA interferometer detector at Gingin site, W. Australia to maximize science benefits like baseline, pointing, duty cycle, technology development and international collaboration. • The proposal from Australian consortium envisages IndIGO as one of the partners to realize this amazing opportunity. • - Indian contribution in hardware (end station vacuum system, and controls), Data centre, manpower for installation and commissioning.

31. Indo-US centre for Gravitational Physics and Astronomy APPROVED for funding (Dec 2010) • Centre of Indo-US Science and Technology Forum (IUSSTF) • Exchange program to fund mutual visits and • facilitate interaction. • Nodal centres: IUCAA , India & Caltech, US. • Institutions: • Indian: IUCAA, TIFR, IISER, DU, CMI - PI: Tarun Souradeep • US: Caltech, WSU - PI: Rana Adhikari

32. The IndIGO data analysis centre • Tier -2 centre with data archival and computational facilities • Inter-institutional proposal for facility • Propose for a high-throughput Computation and GW Data Archival Centre. • Will provide fundamental infrastructure for consolidating GW data analysis expertise in India. Courtesy: Anand Sengupta

33. Objectives of the data centre LIGO Data Grid as a role model for the proposed IndIGO Data Analysis Centre. Courtesy: Anand Sengupta

34. IndIGO Data Centre@IUCAA Indian Initiative in Gravitational-wave Observations • Primary Science: Online Coherent search for GW signal from binary mergers using data from global detector network • Role of IndIGO data centre • Large Tier-2 data/compute centre for archival of g-wave data and analysis • Bring together data-analysts within the Indian gravity wave community. • Puts IndIGO on the global map for international collaboration with LIGO Science Collab. wide facility. Part of LSC participation from IndIGO • 100 Tflops = 8500 cores x 3 GHz/core Need 8500 cores to carry out a half decent coherent search for gravitational waves from compact binaries. (1 Tflop = 250 GHz = 85 cores x 3 GHz / core) • Storage: 4x100TB per year per interferometer. • Network: gigabit backbone, National Knowledge Network. Courtesy: Anand Sengupta, IndIGO

35. 23 July 2011 Dear Bala: I am writing to invite you to attend the next meeting of the Gravitational Wave International Committee (GWIC) to present the GWIC membership application for IndIGO. This in-person meeting will give you the opportunity to interact with the members of GWIC and to answer their questions about the status and plans for IndIGO. Jim Hough (the GWIC Chair) and I have reviewed your application and believe that you have made a strong case for membership……

36. In its road-map with a thirty year horizon, the Gravitational Wave International Committee (a working unit of the International Union of Pure and Applied Physics, IUPAP) has identified the expansion of the global network of gravitational wave interferometer observatories as a high priority for maximizing the scientific potential of gravitational wave observations. We are writing to you to put forward a concept proposal on behalf of LIGO Laboratory (USA) and the IndIGO Consortium, for a Joint Partnership venture to set up an Advanced gravitational wave detector at a suitable Indian site. In what follows this project is referred to as LIGO-India. The key idea is to utilize the high technology instrument components already fabricated for one of the three Advanced LIGO interferometers in an infrastructure provided by India that matches that of the US Advanced LIGO observatories. LIGO-India LIGO-India could be operational early in the lifetime of the advanced versions of gravitational wave observatories now being installed the US (LIGO) and in Europe (Virgo and GEO) and would be of great value not only to the gravitational wave community, but to broader physics and astronomy research by launching an era of gravitational wave astronomy, including, the fundamental first direct detection of gravitational waves. As the southernmost member observatory of the global array of gravitational wave detectors, India would be unique among nations leading the scientific exploration of this new window on the universe. The present proposal promises to achieve this at a fraction of the total cost of independently establishing a fully-equipped and advanced observatory. It also offers technology that was developed over two decades of highly challenging global R&D effort that preceded the success of Initial LIGO gravitational wave detectors and the design of their advanced version.

37. LIGO-India:Why is it a good idea?for India • Has a 20 year legacy and wide recognition in the Intl. GW community with seminal contributions to Source modeling (RRI)& Data Analysis (IUCAA). High precision measurements (TIFR), Participation in LHC (RRCAT) • (Would not make it to the GWIC report, otherwise!) • AIGO/LIGO/EGO strong interest in fostering Indian community • GWIC invitation to IndIGO join as member (July 2011) • Provides an exciting challenge at an International forefront of experimental science. Can tap and siphon back the extremely good UG students trained in India. (Sole cause of `brain drain’). • 1st yr summer intern 2010  MIT for PhD • Indian experimental scientist  Postdoc at LIGO training for Adv. LIGO subsystem • Indian experimental expertise related to GW observatories will thrive and attain high levels due to LIGO-India. • Sendhil Raja, RRCAT, Anil Prabhakar, EE, IIT Madras, Pradeep Kumar, EE, IITK Photonics • Vacuum expertise with RRCAT (S.K. Shukla, A.S. Raja Rao) , IPR (S.K. Bhatt, Ajai Kumar) • Jump start direct participation in GW observations/astronomy • going beyond analysis methodology & theoretical prediction --- to full fledged participation in experiment, data acquisition, analysis and astronomy results. • For once, may be perfect time to a launch into a promising field (GW astronomy) with high end technological spinoffs well before it has obviously blossomed. Once in a generation opportunity to host an Unique International Experiment here.

38. LIGO-India:Why is it a good idea?… for the World • Strategic geographical relocation for GW astronomy • sky coverage gain • distance: • duty cycle: • Potentially large science community in future • Indian demographics: youth dominated – need challenges • excellent UG education system already produces large number of trained in India find frontline research opportunity at home. • Large data analysis trained manpower and facilities exist (and being created.

39. LIGO-India: … the opportunity Strategic Geographical relocation Figure? Network: HIJLV  GMRT Bangalore Mean horizon distance: 1.57 1.63 Detection Volume: 12.0 12.0 Volume Filling factor: 73% 66% Triple Detection Rate(80%):  8.62 8.64 Triple Detection Rate(95%):  11.1 11.1 Sky Coverage:  100% 100% Directional Precision:  2.93 3.00

41. LIGO-India: … the opportunity Strategic Geographical relocation Source localization error 5-15 degrees to ~degree !!! Ellipses version as in LIGO-Aus proposal ?

42. LIGO-India: … the opportunity Strategic Geographical relocation Polarization info Sky coverage ?

43. LIGO-India: … the opportunity Strategic Geographical relocation - the science gain Sky coverage : Synthesized Network beam (antenna power)

44. LIGO-India: … the opportunity Strategic Geographical relocation - the science gain Sky coverage: ‘reach’ /sensitivity in different directions

49. LIGO-India: the concept … • LIGO Lab approached with concept proposal for joint mega-project --- strategic geographical relocation of • Advanced LIGO interferometer detector funded and ready to be shipped by US • Indian contribution in infrastructure : • site • vacuum system • Related Controls • Data centre • trained manpower for installation, commissioning and running for 10 years

50. The Science Payoffs • New Astronomy, New Astrophysics, New Cosmology, New Physics…A New Window ushers a New Era of Exploration • Testing Einstein’s GR in strong and time-varying fields • Testing Black Hole phenomena • Understanding nuclear matter by Neutron star EOS • Neutron star coalescence events • Understanding most energetic events in the universe..Supernovae, Gamma-ray bursts, LMXB’s, Magnetars • New cosmology..SMBHB’s as standard sirens..EOS of Dark Energy • Multi-messenger astronomy • The Unexpected