General Relativistic Gravity in Core Collapse SN: Meeting the Model Needs Lee Samuel Finn Center for Gravitational Wave Physics Meeting the model needs • Importance of GR for SN physics? • Most likely quantitative, not qualitative, except for questions of black hole formation (when, how, mass spectrum)? • Gravitational waves as a diagnostic of supernova physics • General relativistic collapse dynamics makes qualitative difference in wave character Outline • Gravitational wave detection & detector status • Detector sensitivity • Gravitational waves as supernova physics diagnostic LIGO Status • United States effort funded by the National Science Foundation • Two sites • Hanford, Washington & Livingston, Louisiana • Construction from 1994 – 2000 • Commissioning from 2000 – 2004 • Interleaved with science runs from Sep’02 • First science results gr-qc/0308050, 0308069, 0312056, 0312088 Detecting Gravitational Waves: Interferometry t – Global Detector Network LIGO miniGRAIL GEO Auriga CEGO TAMA/ LCGT ALLEGRO Schenberg Nautilus Virgo Explorer AIGO Astronomical Sources: NS/NS Binaries Now: N ~1 MWEG • G,NS over 1 week Target: N ~ 600 • G,NS MWEG over 1 year Adv. LIGO: N ~ • G,NS 6x106 MWEG over 1 year Astronomical Sources: Rapidly Rotating NSs range Pulsar 10-2-10-1 B1951+32, J1913+1011, B0531+21 10-3-10-2 -4 -3 B1821-24, B0021-72D, J1910-5959D, 10 -10 B1516+02A, J1748-2446C, J1910-5959B J1939+2134, B0021-72C, B0021-72F, B0021-72L, B0021-72G, B0021-72M, 10-5-10-4 B0021-72N, B1820-30A, J0711-6830, J1730-2304, J1721-2457, J1629-6902, J1910-5959E, J1910-5959C, J2322+2057 -6 -5 J1024-0719, J2124-3358, J0030+0451, 10 -10 J1744-1134 Preliminary S2 upper limits on ellipticity of Initial, advanced LIGO Limits on for 1 yr 28 known pulsars observation of pulsar @ 10 Kpc Astronomical Sources: Stochastic Background • Primordial or “confusion-limit” Now: < 2x10-2 (preliminary S2 result) • GW Target: < 10-6 in (40,150) Hz over 1 yr • GW Advanced LIGO: < 10-9 in (10, 200) • GW Hz over 1 yr Detector Sensitivity 1 T <h2 >= lim dt h2(t) T →∞ 2T −T ∞ 1 ˜ 2 = lim df hT (f) T →∞ 2T −∞ h(t) |t| <T h (t)= T 0 otherwise ˜ 2 ∞ hT (f) = df lim 0 T →∞ T ˜ 2 hT (f) Sh(f) := lim T →∞ T Taking the final steps • LLO seismic noise exceeds dynamic range of isolation • Isolation retrofit using “advanced LIGO” technology • (Late) Fall ‘04: S4 “re- commission” • Spring ‘05: S5 • 6 months at ~ design sensitivity Detector Sensitivity 1 T <h2 >= lim dt h2(t) T →∞ 2T −T ∞ 1 ˜ 2 = lim df hT (f) T →∞ 2T −∞ h(t) |t| <T h (t)= T 0 otherwise ˜ 2 ∞ hT (f) = df lim 0 T →∞ T ˜ 2 hT (f) Sh(f) := lim T →∞ T Sensitivity to supernovae depends on gravitational wave energy spectrum Gravitational Wave Signature • Zwerger-Mueller: non- relativistic • Dimmelmeier-Font- Mueler: relativistic gravity (but not waveform extraction) • Structural differences • Don’t need to take waveforms seriously to believe qualitative differences robust Time-frequency diagnostic • What can you trust? • Qualitative features are more robust than quantitative ones • Sub-nuclear density bounce: long-lasting, low frequency • Supra-nuclear density bounce: short duration, higher-frequency Role of rotation • Ott et al. model S15A10000.{1,4} • 15 M, differential rotation with 1000 Km characteristic radius • 0.1: higher frequency, shorter duration; bounce is most energetic feature • 0.4: most energetic feature is post-bounce Detection issues • Multiple detectors provide opportunity to identify signal through correlations • Blind deconvolution techniques look for common signal in multiple inputs; can recognize time-shift due to wave incident direction Ott et al. S15A10000.1 Time-frequency diagnostic Time-frequency diagnostic Conclusions • General relativity ... • may be important for SN mechanism; • is important for using grav. waves as physics diagnostic • Don’t need waveform to connect observations to physical models • Look for robust, qualitative differences in signal character.