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The SEXSI Survey: Recent Progress. Megan E. Eckart Caltech with Fiona Harrison, David Helfand, Daniel Stern, Luke Kotredes. Overview. Introduction to the SEXSI sample and optical followup Highlights of the optical/X-ray sample composition Spitzer data high-z type 2 quasar candidates
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The SEXSI Survey: Recent Progress Megan E. Eckart Caltech with Fiona Harrison, David Helfand, Daniel Stern, Luke Kotredes
Overview • Introduction to the SEXSI sample and optical followup • Highlights of the optical/X-ray sample composition • Spitzer data • high-z type 2 quasar candidates • SED’s of spectroscopically ID’d sources
SEXSI Survey • Study dominant contributors to XRB • 1034 2-10 keVsources from 27 Chandra pointings; (2 deg2) • R-band imaging • 438 spectroscopic redshifts from Keck • Harrison et al. 2003, ApJ, 596, 944-956 (Paper 1)
SEXSI Survey • Harrison et al. 2003, ApJ, 596, 944-956 (Paper 1)
Redshift Distribution • Peak: z ~ 0.7 • 34 narrow-lined Lx>1044 sources(type-2 quasar candidates) • nine z > 2, obscured type-2 quasar candidates • Eckart et al. 2006, ApJS, 165, 19-56 (Paper 3)
Fraction Obscured • SEXSI - excellent statistics over flux range ~50% obscuredindependent of luminosity Fraction with log(NH) > 22 log (Unobscured 2-10 keV Luminosity [erg s-1]) • Eckart et al. 2006, ApJS, 165, 19-56 (Paper 3)
Spitzer Data • Spitzer data over five SEXSI fields (IRAC & MIPS) • 250 SEXSI X-ray sources covered • 140 with spectroscopic ID • 62% of total X-ray sources are in “wedge” • 86% of BLAGN • 67% of NLAGN • 28% of ELG • 15% of sources with Lx<10 43.5 erg s-1 • - wedge from Stern et al. (2005)
High-z QSO 2 • - quadrant split from Martinez-Sansigre, Lacy et al. (2005)
High-z QSO 2 • - quadrant split from Martinez-Sansigre, Lacy et al. (2005)
log (n [Hz]) log (n [Hz]) BLAGN SED’s • Many BLAGN fit a typical quasar SED (Elvis et al. 1994) • BUT, there are many that fit a star forming template better in mid-IR/optical (Devriendt et al. 1999 template plotted above)
log (n [Hz]) log (n [Hz]) NLAGN SED’s • Bad match to both templates • (would match an absorbedAGN spectrum …) • Fits star forming template in IR
log (n [Hz]) ELG SED’s • Overwhelming majority (but not all) of ELG fit starforming template
In Progress… Synthesis of spectrally identified and unidentified SED’s X-ray stacking of Spitzer sources with Chandra nondetections Acknowledgements: Fiona Harrison, David Helfand, Dan Stern, Luke Kotredes