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Luigi Piro IASF-INAF Rome. Lighthouses throughout the Universe: Cosmology with GRB. z=6.3 !. The brightest AND most distant sources. E(iso) up to 10 53 -10 54 erg in few seconds. X-ray cosmology with GRB. Tomography of the Universe: Study the evolution of metals & star formation with z
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Luigi PiroIASF-INAFRome Lighthouses throughout the Universe: Cosmology with GRB
z=6.3 ! The brightest AND most distant sources E(iso) up to 1053-1054 erg in few seconds
X-ray cosmology with GRB • Tomography of the Universe: • Study the evolution of metals & star formation with z • The X-ray forest: WHIM • Dark energy and extension of SN results at z>1 • Identify high-z GRB and their obscured host galaxies (X-rays and gamma-rays pierce through) at z=7-20 when the first stars & galaxies formed
Prompt: hard-to-soft Afterglow: a=1 X-ray Tomography with GRB • (Piro et al, ApJ 05)
X-ray absorption in the GRB local environment X-ray absorption column densities in the afterglow: NH=1021-22 cm-2 (Stratta et al 2000, Campana et al 2006) Consistent with NH in Giant Molecular clouds
Tomography of the Universe I Simulations of X-ray edges produced by metals (Si, S, Ar, Fe) by a medium with column density NH=5 1022 cm-2 and solar-like abundances in the host galaxy of a bright GRB at z=5., as observed ESTREMO-WFXRT with an observation starting 60 s after the main pulse and lasting 60 ksec • Map the metal evolution vs z Ar S Fe Si
Tomography of the Universe II: WHIM and the X-ray forest • From models most of the baryons in the locat (z<1-2) Universe in hot or warm filamentary structures heated by the gravitational pull of DM • Observational evidence: X-ray absorption line in the spectrum of bright nearby quasars (e.g. Nicastro et al 2005)
Dark matter & WHIM: X-ray forest Structure simulation from Cen & Ostriker (1999) Simulations of WHIM absorption featuresfrom OVIIas expected from filaments (at different z, with EW=0.2-0.5 eV from Hellsten et al 98) in the l.o.s. toward a GRB with Fluence=4 10-6 as observed with ESTREMO-WFXRT (in 100 ksec). About 10% of GRB (10 events per year per 3sr). See poster by Corsi et al
GRB as standard candles: new rulers to measure the Universe • Ghirlanda et al 2004, Amati et al 2002
Dark GRB and the dark Universe • About 20% of GRB are Dark (no optical afterglow): • Very high extinction in dusty environment • High z events (Ly alpha forest absorption at z>5)
GRB050908: z=6.3 • Kawai et al 2005
ESTREMO/WFXRT • Mission profile: • Wide field monitor in the X/hard-X range to localize transients ·Fast (<1 min) autonomous follow-up observations withX-ray telescope (2000 cm2) with ·High resolution X-ray spectroscopy (0.1-10 keV range, 2eV resolution below 2 keV with TES microcalorimeters) ·wider field (30-60’) for imaging with 5-10” resolution (CCD) for extended faint structures and cluster survey ·Low background: 600 km equatorial orbit (as BeppoSAX) Trade-off study driven by scientific requirements is being carried out
Scientific drivers of ESTREMO/WFXRT • X-ray cosmology: • GRB as cosmological beacons • Study of Cosmological structures in X-Rays: WHIM and Clusters (high resolution spectroscopy and wide imaging in emission) • Extreme physics of transient phenomena in the Universe (Black Holes, GRB engines and progenitors)