HST images of Typical hosts of long duration bursts at z~1(Fruchter et al 2006)

Unusual sites of GRBs Unusual sites of GRBs

in their host galaxiesin their host galaxies Lise Christensen ESO, Chile

Work done with: Paul VreeswijkJesper SollermanChristina ThoeneKlaas WiersemaEmeric Le Floc’h

Host of GRB 980425 - SN 1998 bw (z=0.0085)

FORS BVR VIMOS cube

SN region

Compare with archive data: Magnitudes and Colours have to match Broad band dataExtracted narrow band IFU image has to match narrow band imagesIFU extracted spectra have to match Long slit spectra

30” = 5 kpc

Location of the GRB from HST/STIS

SN region

WR region

Derived properties:

Christensen et al 2008

• H emission line fit - > velocity map -> dynamic mass• H flux -> SFR, Specific SFR <- 24 m Spitzer image• H flux / continuum -> H EW -> age• H/H -> reddening E(B-V) • Flux ratios [OIII]/H / [NII]/HOxygen abundance• Each spectrum > stellar population fitting -> stellar mass,age

12+

log(

O/H

)

unusual emission line ratios?

Dopita et al. 2006