Download Case for INDIGO

IndIGO
Indian Initiative in Gravitational-wave Observations
Detecting Einstein’s Elusive Waves
Opening a New Window to the Universe
Inaugurating Gravitational wave Astronomy
LIGO-India: An Indo-US joint mega-project concept proposal
Bala Iyer, RRI, Bangalore
Chair, IndIGO Consortium Council
On behalf of the IndIGO Consortium
www.gw-indigo.org
Version: pI_v3 Jun 22, 2011 : BI
What are Gravitational waves and
how best to detect them??
Beauty & Precision
Einstein’s General theory of
relativity is considered the most
beautiful, as well as,
theory of modern physics.
It has matched all weak field
experimental tests of Gravitation in the
solar system remarkably well…
Einstein’s Gravity predicts
• Matter in motion Space-time ripples; fluctuations in
space-time curvature that propagate as waves
Gravitational waves (GW)
In GR, as in EM, GW travel at the speed of light ,
are transverse and have two states of polarization.
• GW are a major qualitatively unique
prediction beyond Newton’s gravitation
• Any theory of Gravitation consistent with SR will lead to
GW…However, the properties of GW in different theories of
gravity could be different …
Companion NS
1975 - Hulse and Taylor
Binary Pulsar 1913+16
PPulsar
•Exquisite Lab for Tests of
Nobel prize
GR beyond static & weak
Grav fields
in 1993 !!!
•High quality Pulsar Timing
Data shows that after
correcting for ALL known
relativistic and
astrophysical kinematic
effects, the binary system
is losing orbital energy
•Period (measurable to
50ms accuracy) speeds up
by 14s from 1975-94 as
predicted by Einstein’s GR.
Binary pulsar systems
Nobel Prize clinching evidence for Gravitational
emit gravitational waves
waves BUT still Indirect evidence….
Astrophysical Sources for Terrestrial GW
Detectors
• Compact binary Coalescence: “chirps”
– NS-NS, NS-BH, BH-BH
• Supernovas or GRBs: “bursts”
– GW signals observed in coincidence
with EM or neutrino detectors
• Pulsars in our galaxy: “periodic waves”
– Rapidly rotating neutron stars
– Modes of NS vibration
• Cosmological: “stochastic background” ?
– Probe back to the Planck time (10-43 s)
– Probe phase transitions : window to force
unification
– Cosmological distribution of Primordial black holes
6
GW cause Oscillatory Tidal distortions on a ring of particles
Suspended mirrors of an interferometer act as (freely falling) test masses
(in hor pl for f>>f_pend),undergo tidal deformations leading to path differences
Strain
h  L / L
•Path difference due to tidal distortion  phase difference
•Change in Length manifests as a Change in Transmitted Light
Challenge of GW Detection
A century of waiting
• Two Fundamental Diffs between GR &EM
- Weakness of Gravitation relative to EM (10^-39)
-Massless Spin two nature of Gravitation vs Spin one of EM that
forbids dipole radiation in GR
• A NS-NS Binary in the Virgo cluster (20 Mpc)
produces a strain of h ~ 10–22 – 10–21 .
• For a 4 km detector one must effectively
measure the miniscule displmnt L ~ 10-18 m
• GW detection is about seeing the biggest
things that ever happen by measuring the
smallest changes that have ever been
measured - Harry Collins.
Detecting GW with Laser Interferometer
LIGO Optical Configuration
Power Recycled
Michelson
Interferometer
end test mass
Light bounces back and
forth along arms about
100 times
with Fabry-Perot Arm
Cavities
Light is “recycled”
about 50 times
input test mass
Laser
signal
beam splitter
Difference in distance of Paths  Interference of laser
light at the detector (Photodiode)
Courtesy: Stan Whitcomb
Current Status of World-wide
GW detection efforts
Laser Interferometer Gravitational-wave
Observatory (LIGO) USA, 4 km
IndIGO - ACIGA meeting
11
Virgo
(Cascina, near Pisa, Italy) French-Italian, 3km
Experimental Milestone
Km-scale interferometric GW detectors LIGO and Virgo achieved their
predicted design goals. Strain sensitivity <3x10-23/Sqrt(Hz) at 200 Hz.
Unprecedented sensitivity already allows
• Upper Limits on GW from a variety of Astrophysical sources.
• Improve on Spin down of Crab, Vela pulsars..
Less than 2% available energy in Crab emitted as GW
• Surpass Big Bang nucleosynthesis bound on Stochastic GW..
Pre-dawn GW astronomy
Towards Advanced LIGO & Virgo
Era of Advanced LIGO detectors: 2015
10x sensitivity
10x dist reach
 1000 volume
 >> 1000X event
rate
(reach beyond
nearest super-
clusters)
A Day of Advanced
LIGO Observation >>
A year of Initial LIGO
observation
Mean Expected Annual Coalescence Event Rates
Detector
Generation
Initial LIGO
(2002 -2006)
Advanced LIGO
(10X sensitivity)
(2014+ - …)
NS-NS
NS-BH
BH-BH
0.02
0.0006
0.0009
10.
20.0
40
In a 95% confidence 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.
Need for Long baseline global
Network:
IndIGO opportunities and benefits
Members: All major GW Detector groups
From the GWIC Strategic Roadmap for GW
Science with thirty year horizon (2007)
• “… the first priority for ground-based
gravitational wave detector development is to
expand the network, adding further detectors with
appropriately chosen intercontinental baselines
and orientations to maximize the ability to extract
source information. ….Possibilities for a detector in
India (IndIGO) are being studied..”
•Aside: Invitation to Present on July 10 during GWIC Meeting at
Amaldi9 in Cardiff the IndIGO case for GWIC Membership
18
Global Network of GW Observatories improves…
1. Detection confidence 2. Duty cycle 3. Source direction 4. Polarization info.
GEO: 0.6km
LIGO-LHO: 2km+ 4km
VIRGO: 3km
LCGT 3 km
TAMA/CLIO
LIGO-LLO: 4km
LIGO-India ?
LIGO-Australia?
LIGO-India: … the opportunity
Science Gain from Strategic Geographical Relocation
Source localization error
Courtesy:
S. Fairhurst
LIGO-India plan
1+1 LIGO USA+ Virgo+ LIGO-India
Original Plan
2 +1 LIGO USA+ Virgo
LIGO-Aus plan
1+1 LIGO USA+ Virgo+ LIGO-Aus
Gravitational wave legacy in India
• Indian contribution over two decades, to the global effort for
detecting GW, internationally recognized on two significant fronts
• Seminal contributions to source modeling at RRI [Bala Iyer] and to
GW data analysis at IUCAA [Sanjeev Dhurandhar]
• RRI: Indo-French collaboration for two decades to compute high accuracy
waveforms for in-spiraling compact binaries from which the GW templates used
in LIGO and Virgo are constructed.
• IUCAA: Designing efficient data analysis algorithms involving advanced
mathematical concepts.. Notable contributions include the search for binary inspirals, hierarchical methods, coherent search with a network of detectors and
the radiometric search for stochastic gravitational waves.
• IUCAA has collaborated with most international GW
detector groups and has been a member of the LIGO
Scientific Collaboration (LSC) for a decade.
• At IUCAA, Tarun Souradeep with expertise in CMB data and Planck
has worked to create a bridge between CMB and GW data analysis
challenges.
Indian Gravitational wave community strengths
• Very good students and post-docs produced who are…
* Leaders in GW research abroad [Sathyaprakash, Bose, Mohanty] (3)
*New faculty at premier institutions in India (6) [Gopakumar, Archana
Pai, Rajesh Nayak, Anand Sengupta, K.G. Arun, Sanjit Mitra, P. Ajith?]
• Strong Indian presence in GW Astronomy in the Global
detector network where broad international collaboration is the norm
 relatively easy to get well trained researchers back
• Close interactions with Rana Adhikari (Caltech), B.S. Sathyaprakash
(Cardiff), Sukanta Bose ( WU, Pullman), Soumya Mohanty (UTB), Badri
Krishnan ( AEI) …
• Very supportive International community as reflected in the
International Advisory committee of IndIGO – Chair Abhay Ashtekar
• LIGO-Lab participation in IndIGO schools, commitment to
training and assisting in high end technology tasks
• EGO proposal to explore MoU for GW collaboration:
Roadmap Meeting on Nov 1-2 ,2011 at IUCAA
High precision Expertise in India
• TIFR [C.S. Unnikrishnan] :
High precision experiments and tests of weak forces
– Test gravitation using most sensitive torsional balances and optical sensors.
– Techniques related to precision laser spectroscopy, electronic locking, stabilization.
– G.Rajalakshmi (IIA  TIFR, 3m prototype);
– Suresh Doravari (IIA  LIGO, Caltech expt./AdvLIGO)
• IITM [Anil Prabhakar] and IITK [Pradeep Kumar] (EE depts)
–
–
Photonics, Fiber optics and communications
Characterization and testing of optical components and instruments for use in India..
• RRCAT
– [S.K. Shukla on INDUS, A.S. Raja Rao (exRRCAT)] --UHV
– [Sendhil Raja, P.K. Gupta] - Optical system design, laser based
instrumentation, optical metrology, Large aperture optics, diffractive
optics, micro-optic system design.
– [Rijuparna Chakraborty, France  LIGO/EGO pdf?] Adaptive Optics….
Large experiment expertise in India
• RRCAT….
• IPR
[S.B. Bhatt on Aditya and Ajai Kumar] - UHV experience, Lasers…
Support role in large volume UHV system, Control systems etc
• Groups at BARC and RRCAT : involved in LHC
– providing a variety of components and subsystems like precision magnet positioning
stand jacks, superconducting correcting magnets, quench heater protection supplies and
skilled manpower support for magnetic tests and measurement and help in
commissioning LHC subsystems.
• Teams at Electronics & Instrumentation Groups at BARC
(may be interested in large instrumentation projects in XII plan)
• Groups at ISRO,…….
Multi-Institutional,
Multi-disciplinary Consortium
(2009)
Nodal Institutions
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
CMI, Chennai
Delhi University
IISER Kolkata
IISER Trivandrum
IIT Madras (EE)
IIT Kanpur (EE)
IUCAA, Pune
RRCAT, Indore
TIFR, Mumbai
IPR, Bhatt
Others
•
•
•
RRI
Jamia Milia Islamia
Tezpur Univ
The IndIGO Consortium
IndIGO Council
1.
2.
3.
4.
Bala Iyer
Sanjeev Dhurandhar
C. S. Unnikrishnan
Tarun Souradeep
( Chair)
(Science)
(Experiment)
(Spokesperson)
Data Analysis & Theory
Instrumentation & Experiment
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
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
Bhal Chandra Joshi NCRA, Pune
Rijuparna Chakraborty, Cote d’Azur, Grasse
Rana Adhikari
Caltech, USA
Suresh Doravari
Caltech, USA
Biplab Bhawal
(ex LIGO)
RRI, Bangalore
IUCAA, Pune
TIFR, Mumbai
IUCAA, Pune
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
Sanjeev Dhurandhar
Bala Iyer
Tarun Souradeep
Anand Sengupta
Archana Pai
Sanjit Mitra
K G Arun
Rajesh Nayak
A. Gopakumar
T R Seshadri
Patrick Dasgupta
Sanjay Jhingan
L. Sriramkumar,
Bhim P. Sarma
Sanjay Sahay
P Ajith
Sukanta Bose,
B. S. Sathyaprakash
Soumya Mohanty
Badri Krishnan
IUCAA
RRI
IUCAA
Delhi University
IISER, Thiruvananthapuram
JPL , IUCAA
Chennai Math. Inst., Chennai
IISER, Kolkata
TIFR, Mumbai
Delhi University
Delhi University
Jamila Milia Islamia, Delhi
Phys., IIT M
Tezpur Univ .
BITS, Goa
Caltech , USA
Wash. U., USA
Cardiff University, UK
UTB, Brownsville , USA
Max Planck AEI, Germany
IndIGO: the goals & roles - I
• Provide a common umbrella to initiate and expand GW
related experimental activity and train new technically
skilled manpower
–
–
–
–
–
3m prototype detector in TIFR (funded) - Unnikrishnan
Laser expt. RRCAT, IIT M, IIT K - Sendhil Raja, Anil Prabhakar, Pradeep Kumar
Ultra High Vacuum & controls at RRCAT, IPR, BARC, ISRO, …. Shukla, Raja Rao, Bhatt,
UG summer internship at National & International GW labs & observatories.
Postgraduate IndIGO schools, specialized courses,…
• Seek pan-Indian consolidated IndIGO membership in
LIGO Scientific Collaboration (LSC) for participation in
Advanced LIGO.
• Create a Tier-2 data centre in IUCAA for LIGO Scientific
Collaboration Deliverables and as a LSC Resource
• Start collaborative work on joint projects under the
IUSSTF Indo-US IUCAA-Caltech joint Centre at IUCAA
IndIGO 3m Prototype Detector
Funded by TIFR Mumbai on campus (2010)PI: C. S.Unnikrishnan (Cost ~ INR 2.5cr)
Technology Development and Training Platform
Vibration isolation
schematic
Laser table
Sensing &
Control
180 cm
All mirros and beamsplitters
are suspended as in the diagram on right
Power recycling
Detector
Vacuum
tanks
F-P cavity
3.2 meters
0.8 m
Mirror
60 cm
IndIGO: the goals & roles - II
• Set up a major experimental initiative in GW astronomy
 MOU with ACIGA to collaborate on GW Astronomy
Earlier Plan: Partner 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.
Today: LIGO-India
–
–
–
–
Letter from LIGO Labs with offer of LIGO-India and Requirement Document
Advanced LIGO hardware for 1 detector to be shipped to India.
Two 4km arm length ultra high vacuum tubes in L configuration
India provides suitable site and infrastructure to house the GW observatory, Staffing for
installing, commissioning and operation and 10 year Running costs
– Indian cost ~ Rs 1000Cr
The Science & technology benefit of LIGO-India is
transformational
LIGO-India: Why is it a good idea?
… for the World
• Geographical relocation Strategic for GW astronomy
–
–
–
–
–
–
Increased event rates (x4) by coherent analysis
Improved duty cycle
Improved Detection confidence
Improved Sky Coverage
Improved Source Location required for multi-messenger astronomy
Improved Determination of the two GW polarizations
• Potentially large Indian science user community in the future
– Indian demographics: youth dominated – need challenges
– Improved UG education system will produce a larger number of students
with aspirations looking for frontline research opportunity at home.
• Substantial data analysis trained faculty exists in India and
Large Data Analysis Center Facilities are being planned
LIGO-India: Why is it a good idea?
……..for India
• Jump start direct participation in GW Observations & Astronomy
• Provides an exciting challenge at the International forefront of
experimental science. Can tap and siphon back the extremely
good UG students trained in India. (a cause for `brain drain’).
– 1st yr summer intern 2010  MIT for PhD
– Indian experimental scientist  Postdoc at LIGO training for Adv. LIGO
subsystem; Another Postdoc under consideration in LIGO & EGO
• Experimental expertise related to GW observatories
will thrive and attain high levels due to LIGO-India.
• Challenging endeavour involving unforgiving technology
mandates symbiotic interplay of Engineering and
Science disciplines.. Revival of Advanced Instrumentation
• Inclusive cooperation between Basic science research
Institutes, High Technology DAE Labs, ISRO,..Educational
IISER’s and Universities for highly visible frontier research
Science Payoffs
Synergy with other major Astronomy projects
New Astronomy, New Astrophysics, New Cosmology, New Physics
• SKA : Pulsars timing and GW background, GW from Pulsars ,…
” A( RADIO:
New Window
ushersarray)
a New Era of Exploration in Physics & Astronomy”
Square Kilometer
• –CMB
: GWEinstein’s
from inflation,
phase
transitions,
dark energy
Testing
GR cosmic
in strong
and
time-varying
fields….
(Cosmic Microwave Background : WMAP, Planck, CMBPOl, QUaD,…)
– Testing Black Hole phenomena
• X-ray satellite (AstroSat) : Spacetime near Black Holes, NS, ….
– Understanding
nuclear
matter
byGW
Neutron star EOS
• Gamma
ray observatory:
GRB triggers
from
(FermiLAT,
GLAST,….)
– Neutron
star coalescence events
• Thirty Meter Telescope: Resolving multiple AGNs, optical follow-up, …
– Understanding most energetic cosmic events .. Supernovae, Gamma-ray
• INO: cross correlate neutrino signals from SN event
bursts, LMXB’s, Magnetars
• LSST: Astro-transients with GW triggers, Cosmic distribution of dark
– New
cosmology..SMBHB’s
as standard sirens..
matter
, Dark
energy
•
EOS of Dark Energy
•
– Phase transition related to fundamental unification of forces
– Multi-messenger astronomy
– The Unexpected !
Summary (Part 1)
• LIGO-India will raise public profile of science since it will be
making ongoing discoveries fascinating the young.
GR, BH, EU and Einstein have a special attraction and a pioneering facility in India participating
in important discoveries will provide science & technology role models with high visibility
and media interest. Einstein@home; Black Hole Hunter…
• Opportune to a launch a promising field (GW astronomy)
with high end technological spinoffs, well before it has
obviously blossomed. Once in a generation unique
opportunity to host in India a sophisticated International
Experiment straining to hear the feeble notes of Einstein’s
GW Symphony playing in the universe and deciphering the
dark secrets that light or EMW can never reveal..
• A GREAT opportunity but a very sharp deadline of 31 Mar 2012.
• LIGO-Lab needs to seek NSF nod latest by Dec 2011
– We must be ready with credible plan proposal from
India by Nov 2011
End of Part I
Thank you !!!
Over to Tarun…
IndIGO Advisory Structure
Committees:
International Advisory Committee
Abhay Ashtekar (Penn SU)[ Chair]
Rana Adhikari (LIGO, Caltech, USA)
David Blair (ACIGA &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 (ACIGA&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)
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
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)]
LIGO-India: … the opportunity
Strategic Geographical relocation: science gain
Polarization info
Homogeneity of Sky coverage
Courtesy: S.Kilmenko & G. Vedovato
LIGO-India: … the opportunity
Strategic Geographical relocation: science gain
Sky coverage
: Synthesized
Network
beam
(antenna power)
Courtesy: B. Schutz
LIGO-India: … the opportunity
Strategic Geographical relocation: science gain
Sky coverage: ‘reach’ /sensitivity in different directions
Courtesy: B. Schutz
Strategic Geographical relocation: science gain
Network
HHLV
HILV
AHLV
Mean horizon
distance
1.74
1.57
1.69
Detection
Volume
8.98
8.77
8.93
41.00%
54.00%
44.00%
Triple
Detection
Rate(80%)
4.86
5.95
6.06
Triple
Detection
Rate(95%)
7.81
8.13
8.28
47.30%
79.00%
53.50%
0.66
2.02
3.01
Volume Filling
factor
Sky Coverage:
81%
Directional
Precision
Using GWs to Learn about the Source: an Example
Over two decades,
RRI involved in
computation of
inspiral waveforms
for compact
binaries & their
implications and
IUCAA in its Data
Analysis Aspects.
Can determine
• Distance from the earth r
• Masses of the two bodies
• Orbital eccentricity e and orbital inclination i
Gravitational wave Astronomy :
vit
GWIC Roadmap Document
Unique Technology Payoffs
• Lasers and optics..Purest laser light..Low phase noise, excellent
beam quality, high single frequency power
• Applications in precision metrology, medicine, micro-machining
• Coherent laser radar and strain sensors for earthquake prediction
and other precision metrology
• Surface accuracy of mirrors 100 times better than telescope
mirrors..Ultra-high reflective coatings : New technology for other fields
• Vibration Isolation and suspension..Applications for mineral prospecting
• Squeezing and challenging “quantum limits” in measurements.
• Largest Ultra-high vacuum system 10^-9 torr (1picomHg) in the
region. Such a UHV system will provide industry a challenge and
experience.
• Computation Challenges: Cloud computing, Grid computing, new
hardware and software tools for computational innovation.
Gravitational wave Astronomy :
vit
Synergy with other major Astronomy projects
• SKA : Pulsars timing and GW background, GW from Pulsars ,…
( RADIO: Square Kilometer array)
• CMB : GW from inflation, cosmic phase transitions, dark energy ….
(Cosmic Microwave Background : WMAP, Planck, CMBPOl, QUaD,…)
• X-ray satellite (AstroSat) : Spacetime near Black Holes, NS, ….
• Gamma ray observatory: GRB triggers from GW
(FermiLAT, GLAST,….)
• Thirty Meter Telescope: Resolving multiple AGNs, optical follow-up, …
• INO: cross correlate neutrino signals from SN event
• LSST: Astro-transients with GW triggers, Cosmic distribution of dark
matter , Dark energy
•
•
GWIC Roadmap Document
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……
Invitation to Present IndIGO case for GWIC
Membership on July 10 at GWIC meeting at Cardiff
Space Time as a fabric
Special Relativity (SR) replaced Absolute space and Absolute Time by flat 4dimensional space-time (the normal three dimensions of space, plus a fourth
dimension of time).
In 1916, Albert Einstein published his famous Theory of General Relativity, his
theory of gravitation consistent with SR, where gravity manifests as a curved
4-diml space-time
Theory describes how space-time is affected by mass and also how
energy, momentum and stresses affects space-time.
Matter tells space-time how to curve, and
Space-time tells matter how to move.
Space Time as a fabric
Earth follows a “straight path” in the curved
space-time caused by sun’s mass !!!
What happens when
matter is in motion?
Detecting GW with Laser Interferometer
B
A
Path A
Path B
Difference in distance of Path A & B  Interference of laser
light at the detector (Photodiode)
Indo-Aus.Meeting, Delhi, Feb
2011
Concluding remarks
• A century after Einstein’s prediction, we are on the threshold of a new
era of GW astronomy following GW detection. Involved four decades of
very innovative and Herculean struggle at the edge of science & technology
• First generation detectors like Initial LIGO and Virgo have achieved design
sensitivity  Experimental field is mature
Broken new ground in optical sensitivity, pushed technology and proved technique.
• Second generation detectors are starting installation and expected
to expand the “Science reach” by factor of 1000
• Cooperative science model: A worldwide network is starting to come on line and
the ground work has been laid for operation as a integrated system.
• Low project risk : A compelling Science case with shared science risk, a proven
design for India’s share of task (other part : opportunity w/o responsibility)
• National mega-science initiative: Need strong multi-institutional support
to bring together capable scientists & technologist in India
• An unique once-in-a-generation opportunity for India. India could
play a key role in Intl. Science by hosting LIGO-India.
… Concluding remarks
• A GREAT opportunity but a very sharp deadline of 31 Mar 2012. If we cannot act
quickly the possibility will close. Conditions laid out in the Request Doc of LIGOLab will need to be ready for LIGO-Lab examination latest by Dec 2011 so that in
turn LIGO-Lab can make a case with NSF by Jan 2012.
• Of all the large scientific projects out there, this one is pushing the
greatest number of technologies the hardest.
“Every single technology they’re touching they’re pushing, and there’s a lot
of different technologies they’re touching.”
(Beverly Berger, National Science Foundation Program director for gravitational physics. )
• One is left speculating if by the centenary of General
Relativity in 2015, the first discovery of Gravitational
waves would be from a Binary Black Hole system, and
Chandrasekhar would be doubly right about
Astronomy being the natural home of general relativity.
Initial LIGO Sensitivity Goal
• Strain sensitivity
<3x10-23 1/Hz1/2
at 200 Hz

Sensor Noise
» Photon Shot Noise
» Residual Gas

Displacement Noise
» Seismic motion
» Thermal Noise
» Radiation Pressure
52
Advanced LIGO
•Take advantage of new technologies and on-going R&D
>> Active anti-seismic system operating to lower frequencies:
(Stanford, LIGO)
>> Lower thermal noise suspensions and optics :
(GEO )
>> Higher laser power 10 W  180 W
(Hannover group, Germany)
>> More sensitive and more flexible optical configuration:
Signal recycling
• Design: 1999 – 2010 : 10 years of high end R & D internationally.
• Construction: Start 2008; Installation 2011; Completion 2015
A Century of Waiting
• Almost 100 years since Einstein predicted GW but no
direct experimental confirmation (a la Hertz for
Maxwell EM theory)
• 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 any Detector
• GW Hertz experiment ruled out. Only astrophysical systems
involving huge masses and accelerating very strongly are
potential detectable sources of GW signals.
GW  Astronomy link
Astrophysical systems are sources of copious GW emission:
•GW emission efficiency (10% of mass for BH mergers) >>
EM radiation via Nuclear fusion (0.05% of mass)
Energy/mass emitted in GW from binary >> EM radiation in the lifetime
• Universe is buzzing with GW signals from cores of astrophysical events
Bursts (SN, GRB), mergers, accretion, stellar cannibalism ,…
• Extremely Weak interaction, hence, has been difficult to detect directly
But also implies GW carry unscreened & uncontaminated signals
Scientific Payoffs
Advanced GW network sensitivity needed to observe
GW signals at monthly or even weekly rates.
• Direct detection of GW probes strong field regime of gravitation
 Information about systems in which strong-field and time dependent gravitation
dominates, an untested regime including non-linear self-interactions
• GW detectors will uncover NEW aspects of the physics
 Sources at extreme physical conditions (eg., super nuclear density physics), relativistic
motions, extreme high density, temperature and magnetic fields.
• GW signals propagate un-attenuated
weak but clean signal from cores of astrophysical event where EM signal is screened by
ionized matter.
• Wide range of frequencies  Sensitivity over a range of astrophysical scales
To capitalize one needs a global array of GW antennas separated by
continental distances to pinpoint sources in the sky and extract all the
source information encoded in the GW signals
Principle behind Detection of GW
LIGO-India from LIGO
Dear Prof. Kasturirangan,
1 June 2011
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 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.
Binary Pulsars..NS-NS Binary
Pulsar
companion
High quality observational data that GW exist….
Indian Gravitational wave strengths
• Very good students and post-docs produced from this.
* Leaders in GW research abroad [Sathyaprakash, Bose, Mohanty] (3) *
*New faculty at premier Indian institutions (6) [Gopakumar, Archana Pai,
Rajesh Nayak, Anand Sengupta, K.G. Arun, Sanjit Mitra, P. Ajith?]
–
–
–
–
Gopakumar (Jena  TIFR) and Arun (Virgo  CMI) : PN modeling, dynamics of CB, Ap and
cosmological implications of parameter estimation
Rajesh Nayak (UTB  IISER K) , Archana Pai (AEI  IISER T), Anand Sengupta (LIGO,
Caltech Delhi), Sanjit Mitra (JPL  IUCAA ): Extensive experience on single and multi-detector
detection, hierarchical techniques, noise characterization schemes, veto techniques for GW transients,
bursts, continuous and stochastic sources, radiometric methods, …
P. Ajith (Caltech, LIGO/TAPIR  ? ) ……
Sukanta Bose (Faculty UW, USA  ?)
Strong Indian presence in GW Astronomy with Global detector network
 broad international collaboration is the norm
 relatively easy to get people back.
•
Close interactions with Rana Adhikari (Caltech), B.S. Sathyaprakash (Cardiff),
Sukanta Bose ( WU, Pullman), Soumya Mohanty (UTB), Badri Krishnan ( AEI) …
• Very supportive International community reflected in International
Advisory committee of IndIGO – Chair Abhay Ashtekar
• EGO-IndIGO meeting on Nov 1-2 ,2011 at IUCAA to explore
collaboration
LIGO-India: Why is it a good
……..for India
idea?
• Provides
an exciting
challenge
at anAstronomy
Internationalprojects
forefront of
Synergy
with other
major
experimental science. Can tap and siphon back the extremely
good
UG
students
trained
India. (aGW
cause
`brain
• SKA
: Pulsars
timing
and GWinbackground,
fromfor
Pulsars
,…
( RADIO: Square Kilometer array)
drain’).
• CMB : GW from inflation, cosmic phase transitions, dark energy ….
– 1st yr summer intern 2010  MIT for PhD
(Cosmic Microwave Background : WMAP, Planck, CMBPOl, QUaD,…)
– Indian experimental scientist  Postdoc at LIGO training for Adv. LIGO
• X-ray satellite (AstroSat) : Spacetime near Black Holes, NS, ….
subsystem
• Gamma ray observatory: GRB triggers from GW
(FermiLAT,
GLAST,….)
• Indian
experimental
expertise related to GW
• Thirty Meter Telescope:
Resolving
follow-up,
observatories
will thrive
and multiple
attainAGNs,
highoptical
levels
due to…
• INO: cross correlate neutrino signals from SN event
LIGO-India.
• LSST: Astro-transients with GW triggers, Cosmic distribution of dark
matter , Dark interplay
energy
• Symbiotic
of Engineering and Science
•
disciplines
for a challenging endeavour involving
•
unforgiving technology
• Jump start direct participation in GW Observations &
Astronomy
LIGO-India: Why is it a good
……..for India
idea?
• Provides an exciting challenge at an International forefront of
experimental science. Can tap and siphon back the extremely
good UG students trained in India. (a cause for `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.
• Symbiotic interplay of Engineering and Science
disciplines for a challenging endeavour involving
unforgiving technology
• Jump start direct participation in GW Observations &
Astronomy
Indirect evidence for Gravitational waves
Binary pulsar systems emit gravitational waves
•
leads to loss of orbital energy
•
period speeds up 14 sec from
1975-94
High quality Pulsar Timing Data..
•
measured to ~50 msec accuracy
•
deviation grows quadratically
with time
Pulsar
companion
Hulse and Taylor
Results for PSR1913+16
Oscillatory Tidal Effect of GW on a ring of test masses
If Interferometer mirrors are the test masses
•Path difference due to tidal distortion  phase difference
•The effects of gravitational waves appear as a fluctuation in the phase
differences between two orthogonal light paths of an interferometer.
Equal arms:
Dark fringe
Unequal arm:
Signal in PD
Rewards and Spinoffs
Detection of GW is the epitome of breakthrough science!!!
• LIGO-India  India could become a partner in
international science of Nobel Prize significance
• GW detection is an instrument technology intensive field pushing
frontiers simultaneously in a number of fields like lasers and
photonics. Will impact allied areas and smart industries.
• The imperative need to work closely with industry and other end
users will lead to spinoffs as GW scientists further develop optical
sensor technology. Presence of LIGO-India will lead to pushing
technologies and greater innovation in the future.
• Increase number of research groups performing at world class levels
and produce skilled researchers. Increase international collaborations
in Indian research & Potential for Indian Science Leadership in the
Asia-Pacific region.
• LIGO has a strong outreach tradition and LIGO-India will provide a