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Cosmological Backgrounds of Neutrinos, Photons, And Gravitational Waves. Supernovae as neutrino and gravitational wave sources. G ü nter Sigl GReCO, Institut d’Astrophysique de Paris, CNRS et Fédération de Recherche Astroparticule et Cosmologie, Université Paris 7 - PowerPoint PPT Presentation
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Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Supernovae as neutrino and gravitational wave sources
Cosmological Backgrounds ofNeutrinos, Photons,
And Gravitational Waves
Günter SiglGReCO, Institut d’Astrophysique de Paris, CNRS etFédération de Recherche Astroparticule et Cosmologie, Université Paris 7http://www2.iap.fr/users/sigl/homepage.html
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Onion structure of a supernova
Convection, turbulence
Janka, Mueller
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Supernovae as Neutrino and Gravitational Wave Sources
Anisotropic mass motion and neutrino emission in massive star collapse leadsto gravitational wave emission. At low frequencies neutrino emission withluminosity Lν(t) and anisotropy q(t) dominates and leads todimensionless strain at distance D:
2
)()(
)()( 2
)(
0
N
thffh
tqtLtdD
Gth
f
Dt
L(t)memory h(t)
q(t)
A rotating core collapse model by Müller & Janka
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
neutrino spectra gravitational wave spectra
Simulated individual signals
ordinary SN
≥100Msun PopIII
Individual supernovae (SN) in our Galaxy can give prominent signalsin neutrinos in Super-Kamiokande, Amanda, ICECUBE, Uno… and ingravitational waves in Virgo/EGO, LIGO…, but are RARE events.
2x10-3 Msun in gw, <q>~3%
10-8 Msun in gw, <q>~0.5%
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
The background is then given by integration over all events
The Gaussianity of the signal is given by the “duty factor” which is proportionalto the event rate:
Where τ(f) is the time scale over which frequency f is emitted “coherently”In a given event. For us: τ(f)~1/f
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Ordinary SN ~ 1/sec
+ very massive PopIII starsat z ≥ 15 with rate
~ 0.2 (fIII/10-3)/sec,
where fIII = baryon fractioncycled thru PopIII stars.
future input from SWIFT…
However, backgrounds from cosmological SN may soon be detectableby gadolinium upgrade of Super-K in neutrinos and by gravitational wavedetectors such as the Big Bang Observatory (BBO).
SN rate
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
=>diffuse neutrino spectra from ordinarySN close to current sensitivities stochastic gravitational wave backgroundAndo and Sato, astro-ph/0410061 Buonanno, Sigl, Raffelt, Janka, Mueller,
Phys.Rev.D 72 (2005) 084001
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Diffuse infrared background can not be explained bygalaxies alone -> may need a Pop III contribution
Dwek et al., astro-ph/0508262
Pop III fraction of baryons fIII and infraredbackground resulting from Lyα emission
Madau, Silk., astro-ph/0502304
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Fate of a massive star as function of progenitor mass and metallicity
low metallicity: less cooling, larger progenitor masses,less mass loss, more powerful explosions.
Heger et al., astro-ph/0211062
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Fate of a massive star as function of progenitor mass and metallicity
Heger et al., astro-ph/0211062
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Compare this with upper limits, sensitivities, and cosmological predictions
Giovannini
BBO
BBO correlated
SN and PopIII
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Consequence:Gravitational Wave Background from type II supernovae and PopIII stars
could mask inflationary background
Günter Sigl, Astroparticules et Cosmologie, ParisILIAS/N5-N6 meeting, Paris, January 23-24, 2006
Conclusions
There is a deep connection between neutrino and gravitational wave emission by collapsing massive stars. Both signals have good chances to be seen by future experiments.
