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Finding The First Cosmic Explosions. Daniel Whalen Carnegie Mellon University Chris Fryer, Lucy Frey LANL. ~ 200 pc. Cosmological Halo z ~ 20. Properties of the First Stars. form in isolation (one per halo) very massive (25 - 500 solar masses) due to inefficient H 2 cooling
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Finding The First Cosmic Explosions Daniel Whalen Carnegie Mellon University Chris Fryer, Lucy Frey LANL
~ 200 pc Cosmological Halo z ~ 20
Properties of the First Stars • form in isolation (one per halo) • very massive (25 - 500 solar masses) due to inefficient • H2 cooling • Tsurface ~ 100,000 K • extremely luminous sources of ionizing and LW photons • (> 1050 photons s-1) • 2 - 3 Myr lifetimes
Transformation of the Halo Whalen, Abel & Norman 2004, ApJ, 610, 14
Primordial Ionization Front Instabilities Whalen & Norman 2008, ApJ, 675, 644
Final Fates of the First Stars Heger & Woosley 2002, ApJ 567, 532
Post Processing Includes Detailed LANL Opacities but the atomic levels are assumed to be in equilibrium, a clear approximation
PISN Shock Breakout • X-rays (> 100 eV) • transient (a few • hours in the local • frame)
Spectra at Breakout The spectra evolve rapidly as the front cools
Long-Term Light-Curve Evolution even the lowest energy PISN at z ~ 10 produces a large signal in the JWST NIR camera over the first 50 days
Late Time Spectra spectral features after breakout may enable us to distinguish between PISN and CC SNe larger parameter study with well-resolved photospheres is now in progress
Chemical Mixing Prior to Breakout Core Collapse SN PISN Joggerst, Whalen, et al 2010, ApJ, 709, 11 Joggerst & Whalen 2010, ApJ in prep
Roadmap Ahead • current models are grey FLD; next step is • multigroup FLD and then multigroup IMC • advance from 1D RTP AMR calculations • to 2D cartesian AMR grids • incorporate mixing from 2D models to • simulate core-collapse SNe (15 - 40 solar • mass stars, hypernovae) • implement non-equilibrium opacities • investigate progenitor environments on • LC and spectra (LBV brightening?) • explore asymmetric explosion mechanisms • evolve toward 2D AMR IMC rad hydro • with thousands of frequency bins -- eliminate • post processing
Conclusions • PISN will be visible to JWST out to z ~ 15; strong lensing may • enable their detection out to z ~ 20 (Holz, Whalen & Fryer 2010 • ApJ in prep) • however, the redshifted initial x-ray transient will likely fall outside • of the trigger wavelength of SWIFT and its envisioned successors • as a consequence, first detection of PISN by JWST would be • serendipitous • dedicated ground-based campaigns with 30-meter class telescopes • are the most probable avenue to finding the first SN explosions • discrimination between Pop III PISN and Pop III CC SNe will be • challenging but offers the first direct constraints on the Pop III IMF • complementary detection of Pop III PISN remnants by the SZ effect • may be possible (Whalen, Bhattacharya & Holz 2010, ApJ in prep)