Documents pour LISA LISA Science case Science Requirement

Documents pour LISA : • LISA Science case • Science Requirement Document Pierre Binétruy LISA-France, LAPP, 1 er février 2007 http: //www. lisa-science. org/resources/talks-articles/science

LISA Science Case Goal: present to an educated reader (typically a member of a committee such as BEPAC) the science case of LISA. Contributors and editors: John Baker (GSFC), Pete Bender (U. of Colorado), Pierre Binetruy (APC - Paris), Joan Centrella (GSFC), Teviet Creighton (JPL), Jeff Crowder (JPL) , Curt Cutler (JPL), Karsten Danzman (U. of Hannover and A. E. I. ), Steve Drasco (JPL) , Lee S. Finn (U. of Pennsylvania), Craig Hogan (U. of Washington), Cole Miller (U. of Maryland), Miloslavljevic (U. of Texas, Austin), Gijs Nelemans (Radboud University Nijmegen), Sterl Phinney (Caltech), Tom Prince (Caltech/JPL), Bonny Schumaker (JPL), Bernard Schutz (A. E. I. ), Michele Vallisneri (JPL), Marta Volonteri (Univ. of Michigan) and Karen Willacy (JPL).

LISA Science Case Goal: present to an educated reader (typically a member of a committee such as BEPAC) the science case of LISA. Contributors and editors: John Baker (GSFC), Pete Bender (U. of Colorado), Pierre Binetruy (APC - Paris), Joan Centrella (GSFC), Teviet Creighton (JPL), Jeff Crowder (JPL) , Curt Cutler (JPL), Karsten Danzman (U. of Hannover and A. E. I. ), Steve Drasco (JPL) , Lee S. Finn (U. of Pennsylvania), Craig Hogan (U. of Washington), Cole Miller (U. of Maryland), Miloslavljevic (U. of Texas, Austin), Gijs Nelemans (Radboud University Nijmegen), Sterl Phinney (Caltech), Tom Prince (Caltech/JPL), Bonny Schumaker (JPL), Bernard Schutz (A. E. I. ), Michele Vallisneri (JPL), Marta Volonteri (Univ. of Michigan) and Karen Willacy (JPL).

List of contents Executive Summary 1. Gravitational Waves: An Overview 2. 2. LISA Mission Overview 3. Black Hole Astrophysics: Massive Black Holes in Galactic Nuclei 4. Black Hole Physics: Confronting General Relativity with Precision Measurements of Strong Gravity 5. Precision Cosmometry and Cosmology 6. Ultra-compact binaries 7. New Physics and the Early Universe 8. LISA and the Key Questions of Astronomy and Physics

Executive Summary 1. Gravitational Waves: An Overview 2. 2. LISA Mission Overview 3. Black Hole Astrophysics: Massive Black Holes in Galactic Nuclei 4. Black Hole Physics: Confronting General Relativity with Precision Measurements of Strong Gravity 5. Precision Cosmometry and Cosmology 6. Ultra-compact binaries 7. New Physics and the Early Universe 8. LISA and the Key Questions of Astronomy and Physics

Key science questions • When did the massive black holes in galactic nuclei form, and how did they grow? • What fraction of proto-galaxies contained massive black holes in their cores, as a function of redshift? • What are the mass and spin distributions of the supermassive black holes in galactic nuclei? • What is the role of black hole mergers in early hierarchical structure assembly? • What are dynamics of stars near massive black holes in galactic nuclei?

1% duty cycle Characteristic time for BH in AGN to increase their mass by accretion: t ~ Mc 2/ LEdd ~ 4 107 ( / 0. 1) yr ~ tuniverse /100 at redshift z ~ 1 efficiency of radiation production Expect BH present in galaxies are active 1% of the time

MBH in M The coupled evolution of galaxies and their nuclear BH galaxy bulge velocity dispersion ( depth of gravit. Potential well)

Mass density of local BH BH = 2 to 5 105 M Mpc-3 Most comes from BH of mass between 108 and 109 M Increase in density of BH if total energy in AGN was produced by accretion BH ~ 3. 5 105 ( / 0. 1)-1 M Mpc-3 Supermassive BH growing by accretion? Smaller ones by merger?

Growth and merger history of massive black holes Merger rate : 1 per year (1010 galaxies seen by HST have fossile evidence of a merger since z=1 i. e. 1010 years)

Stellar captures and the dynamics of galactic nuclei EMRI events (S/M 2) ~ 10 -4 e. g. diffusion of stars through 2 -body collisions

List of contents Executive Summary 1. Gravitational Waves: An Overview 2. 2. LISA Mission Overview 3. Black Hole Astrophysics: Massive Black Holes in Galactic Nuclei 4. Black Hole Physics: Confronting General Relativity with Precision Measurements of Strong Gravity 5. Precision Cosmometry and Cosmology 6. Ultra-compact binaries 7. New Physics and the Early Universe 8. LISA and the Key Questions of Astronomy and Physics

Key Science Questions • Is the strong field gravity correctly described by GR? • Are the massive dark central objects in galaxies really black holes?

M 1 = M 2 = 2 105 M , z=5

Merger stage S/N

EMRI : precision probes of Kerr spacetimes

List of contents Executive Summary 1. Gravitational Waves: An Overview 2. 2. LISA Mission Overview 3. Black Hole Astrophysics: Massive Black Holes in Galactic Nuclei 4. Black Hole Physics: Confronting General Relativity with Precision Measurements of Strong Gravity 5. Precision Cosmometry and Cosmology 6. Ultra-compact binaries 7. New Physics and the Early Universe 8. LISA and the Key Questions of Astronomy and Physics

Key science questions • What is the nature of dark energy? • What is the global geometry of the Universe? • What is the Hubble constant?

Inspiral phase Key parameter : chirp mass M (z) = (m 1 m 2)3/5 (m 1 + m 2)1/5 (1+z)

Inspiral phase Key parameter : chirp mass M (z) = (m 1 m 2)3/5 (m 1 + m 2)1/5 . 2 1. 2 M 1 Binary system : L = -- M R + -- r + G ---r 2 2 (1+z) R=r 1+r 2 r=r 1 -r 2 Defining r^ = 1/2 r, the relative motion depnds on the mass only through: M = ( 3 M 2)1/5

Inspiral phase Key parameter : chirp mass M (z) = (m 1 m 2)3/5 (m 1 + m 2)1/5 (1+z)

Inspiral phase Key parameter : chirp mass M (z) = Amplitude of the gravitational wave: h(t) = Luminosity distance M(z)5/3 f(t)2/3 d. L (m 1 m 2)3/5 (m 1 + m 2)1/5 (1+z) frequency f(t) = d /2 dt F (angles) cos (t)

Inspiral phase Key parameter : chirp mass M (z) = (m 1 m 2)3/5 (m 1 + m 2)1/5 (1+z) Amplitude of the gravitational wave: h(t) = Luminosity distance M(z)5/3 f(t)2/3 d. L F (angles) cos (t) poorly known in the case of LISA arcmin ~ 10 SNR 1 Hz f. GW

z = 1 , m 1 = 105 M , m 2 = 6. 105 M 3° (arcminutes) 5% d /d Holz & Hughes

Using the electromagnetic counterpart Allows both a measure of the direction and of the redshift 0. 5% d. L/d. L Holz and Hughes

3000 supernovae 100 SMBH sources

Executive Summary 1. Gravitational Waves: An Overview 2. 2. LISA Mission Overview 3. Black Hole Astrophysics: Massive Black Holes in Galactic Nuclei 4. Black Hole Physics: Confronting General Relativity with Precision Measurements of Strong Gravity 5. Precision Cosmometry and Cosmology 6. Ultra-compact binaries 7. New Physics and the Early Universe 8. LISA and the Key Questions of Astronomy and Physics

Key science questions • Is general relativity the correct theory of gravitation? • Is there a large population of ultra-compact binaries in the Galaxy? • How did compact binaries form and what is the outcome of a common-envelope phase? • What is the nature of the fundamental physical interactions in compact binaries? • How are the compact binaries distributed in the Galaxy and what does that tell us about the formation and evolution of the Galaxy?

Neutron star binaries NS Ultra-compact X-ray sources S/N = 5 S/N = 1 AM CVn systems resolved WD binaries average WD binary bkgd WD

Several thousands WD binaries individually detected (d< 100 kpc) Period less than 20 minutes Several millions unresolved form a background.

Verification binaries

Studying the astrophysics of compact binaries using LISA • physics of tidal interaction • physics of mass-tranfer stability • double WD mergers • neutron star and BH binaries • millisecond X-ray pulsars

Executive Summary 1. Gravitational Waves: An Overview 2. 2. LISA Mission Overview 3. Black Hole Astrophysics: Massive Black Holes in Galactic Nuclei 4. Black Hole Physics: Confronting General Relativity with Precision Measurements of Strong Gravity 5. Precision Cosmometry and Cosmology 6. Ultra-compact binaries 7. New Physics and the Early Universe 8. LISA and the Key Questions of Astronomy and Physics

Key science questions • Is there a first-order phase transition at or beyond Te. V energies? • Are there extra dimensions at the submillimeter scale? • Do stable superstrings exist, and can they be blown up to form cosmic strings? • What was the quantum state of the Universe at or before the Big Bang? • How did inflation end? • Were there violent events in the early Universe that left no relic trace in conventional particles and fields?

Gravitons of frequency f* produced at temperature T* are observed at a redshifted frequency f = 1. 65 10 -7 Hz At production Wavelength 1 -- ( T* ----1 Ge. V 1/6 )( ) g* ---100 * = H*-1 (or f* = H*/ ) Horizon length

1 d GW GW = ------- c d logf , c = 3 H 0/(8 GN) for =1 Gravitons produced at the electroweak phase transition would be observed in the LISA window.

But are gravitons produced in sufficient numbers at the electroweak phase transition? If the transition is first order, nucleation of true vacuum bubbles inside the false vacuum Collision of bubbles and turbulence production of gravitational waves

Science objectives 1. 2. 3. Understand the formation of massive black holes 1. 1. Search for a population of seed black holes at early epochs. 1. 2. Search for remnants of the first (Pop III) stars through observation of intermediate mass black hole captures, also at later epochs. 4. 5. 2. Trace the growth and merger history of massive black holes and their host galaxies 2. 1. Determine the relative importance of different black hole growth mechanisms as a function of redshift. 2. 2. Determine the merger history of two black holes before the era of the earliest known quasars (z ~ 6). 2. 3. Determine the merger history of two black holes at later epochs (z < 6). 6. 7. 8. 9. 3. Explore stellar populations and dynamics in galactic nuclei 3. 1. Characterize the immediate environment of MBHs in z < 1 galactic nuclei from EMRI capture signals. 10. 3. 2. Study intermediate-mass black holes from their capture signals. 11. 3. 3. Improve our understanding of stars and gas in the vicinity of Galactic black holes using coordinated gravitational and electromagnetic observations.

4. 5. 6. 7. Survey compact stellar-mass binaries and study the structure of the Galaxy 4. 1. Elucidate the formation and evolution of Galactic stellar-mass binaries: constrain the diffuse extragalactic foreground. 4. 2. Determine the spatial distribution of stellar mass binaries in the Milky Way and environs. 4. 3. Improve our understanding of white dwarfs, their masses, and their interactions in binaries and enable combined gravitational and electromagnetic observations. 8. 5. Confront General Relativity with observations 9. 5. 1. Detect gravitational waves directly and measure their properties precisely. 5. 2. Test whether the central massive objects in galactic nuclei are the black holes of general relativity. 5. 3. Make precision tests of dynamical strong-field gravity. 6. 7. 8. 9. Probe new physics and cosmology with gravitational waves 6. 1. Study cosmic expansion history, geometry and dark energy using precise gravitationally calibrated distances in cases where redshifts are measured. 6. 2. Measure the spectrum of, or set bounds on, cosmological backgrounds. 6. 3. Search for burst events from cosmic string cusps. 10. 7. Search for unforeseen sources of gravitational waves

Science objectives proposed 4. 1 Understand the formation and growth of massive black holes 4. 2 Trace the birth and evolution of galaxies 4. 3 Explore stellar populations and their dynamics in galactic nuclei 4. 4 Survey compact stellar-mass binaries and study the morphology of the Galaxy 4. 5 Confront general relativity with observations 4. 6 Probe the early universe 4. 7 Search for new phenomena

New science objectives 4. 1 Understand the formation of massive black holes 4. 2 Trace the growth and merger history of massive black holes and their co-evolution with galaxies 4. 3 Explore stellar populations and their dynamics in galactic nuclei 4. 4 Survey compact stellar-mass binaries and study the structure of the Galaxy 4. 5 Confront general relativity with observations 4. 6 Probe the early universe 4. 7 Search for new phenomena

4. 1 Understand the formation of massive black holes 4. 1. 1. Search for the earliest massive black holes and elucidate their formation mechanism 4. 1. 2. Search for the remnants of the first (Pop III) star formation through observation of intermediate-mass black hole capture

4. 2 Trace the growth and merger history of massive black holes and their co-evolution with galaxies 4. 2. 1. Determine the relative importance of different growth mechanisms as a function of redshift 4. 2. 2 Determine the merger history of small black holes (MBHs ~104 to 3 105 M ) in the era of formation of the first galaxies (6<z<30) 4. 2. 3 Determine the merger history of black holes (MBH's 3~105 to 107 M ) in established galaxies (z<6)

4. 3 Explore stellar populations and their dynamics in galactic nuclei 4. 3. 1 Characterize the immediate environment of MBHs in z<1 galactic nuclei from EMRI capture signals (was 4. 2. 1) 4. 3. 2 Study intermediate-mass black holes, and gather evidence about Pop III star formation, from IMRI capture signals

4. 3 Explore stellar populations and dynamics in galactic nuclei 4. 3. 1 Characterize the immediate environment of MBHs in z<1 galactic nuclei from EMRI capture signals 4. 3. 2 Study intermediate-mass black holes from their capture signals 4. 3. 3 Improve our understanding of stars and gas in the vicinity of massive black holes using coordinated gravitational and electromagnetic observations

4. 4 Survey compact stellar-mass binaries and study the morphology of the Galaxy 4. 4. 1 Elucidate the evolutionary history of galactic and extragalactic stellar-mass binaries (was 5. 4. 2) 4. 4. 2 Determine the spatial distribution of stellar mass binaries in the Milky Way, satellite galaxies and globular clusters 4. 4. 3 Improve our understanding of white dwarfs, their masses, and their interactions in binaries using coordinated gravitational and electromagnetic observations (was A&A 5. b)

4. 4 Survey compact stellar-mass binaries and study the structure of the Galaxy 4. 4. 1 Elucidate the formation and evolution of Galactic stellar-mass binaries; constrain the diffuse extragalactic background 4. 4. 2 Determine the spatial distribution of stellar mass binaries in the Milky Way and environs. 4. 4. 3 Improve our understanding of white dwarfs, their masses, and their interactions in binaries using coordinated gravitational and electromagnetic observations

4. 5 Confront general relativity with observations 4. 5. 1 Detect gravitational waves directly and explore their properties 4. 5. 2 Make precision tests of strong-field gravity 4. 5. 3 Verify that the central massive objects in galactic nuclei are Kerr black holes (was 4. 2. 2)

4. 5 Confront general relativity with observations 4. 5. 1 Detect gravitational waves directly and measure their properties precisely 4. 5. 2. Test to high accuracy whether the central massive objects in galactic nuclei are the black holes of general relativity 4. 5. 3 Make precision tests of dynamical strong-field gravity

4. 6 Probe the early universe 4. 6. 1 Enable studies of the expansion history of the universe using precise gravitationally calibrated distances to objects where a host galaxy has been identified (was A&A 5 a and P&C 3 a) 4. 6. 2 Detect or set bounds on cosmological backgrounds 4. 7 Search for new phenomena

4. 6 Probe the early universe 4. 6. 1 Precisely measure gravitationally calibrated luminosity distances for precision cosmology when redshifts can be determined 4. 6. 2 Detect or set bounds on cosmological backgrounds 4. 7 Search for new phenomena

Science requirement document

Changes of Quantitative Requirements between SRD v 3 and Sc. RD v 4 i

Intermediate frequency requirements No substantial differences between 0. 1 and 50 m. Hz

Strain sensitivity Low frequency requirements 1) v 3: Lowest frequency requirement is 0. 03 m. Hz 2) v 4 i: Lowest frequency requirement is 0. 1 m. Hz 3) 0. 03 m. Hz 4) v 3: 2. 6 x 10 -16 Hz-1/2 5) v 4 i: Goal at 3 x 10 -16 Hz-1/2 6) 0. 1 m. Hz 7) v 3: 3. 9 x 10 -17 Hz-1/2 8) v 4 i: 3. 9 x 10 -17 Hz-1/2

High frequency requirements v 3: Highest frequency requirement is 1 Hz v 4 i: Highest frequency requirement is 0. 05 Hz 50 m. Hz v 3: No requirement v 4 i: 6. 5 x 10 -20 Hz-1/2 100 m. Hz v 3: 7. 5 x 10 -20 Hz-1/2 v 4 i: 8 x 10 -20 Hz-1/2 (calculation needed; discovery potential) 1 Hz v 3: 7. 5 x 10 -19 Hz-1/2 v 4 i: Goal : 1. 5 x 10 -18 Hz-1/2

Other Requirements 4) Arm Configuration v 3: 3 arm configuration required v 4 i: No requirement, rather a goal of 6 links 5) Mission Lifetime Unchanged: Both have 5 year requirement 6) Data Availability v 3: 4 days uninterrupted around merger time w/ 2 weeks notice v 4 i: 4 days uninterrupted around merger time w/ 2 weeks notice 7) Minimum Requirements 8) Unchanged

Summary Table of Strain Sensitivity (units of 10 -20 Hz-1/2 & e. g. 2. 6(4) = 2. 6 x 104) 0. 03 m. Hz 0. 1 m. Hz 0. 5 m. Hz 1. 0 m. Hz 5 m. Hz 10 m. Hz 50 m. Hz 100 m. Hz v 3 2. 6 (4) 3. 9 (3) 4. 3 (2) 3. 0 (1) 1. 1 1. 3 None 7. 5 v 4 i None 3. 9 (3) None 3. 2 (1) 1. 1 1. 3 6. 5 1 Hz 7. 5 (1) None