the afterglow and host galaxy of grb 090205: evidence for a ly- α emitter at z = 4.65
DESCRIPTION
The afterglow and host galaxy of GRB 090205: evidence for a Ly- α emitter at z = 4.65. Paolo D’Avanzo (INAF-Osservatorio Astronomico di Brera);. in collaboration with:. GRB 090205. 15-350 keV. T 90 = 8.8 ± 1.8 s. Perri et al. 2009, GCN 8884 Cummings et al. 2009, GCN 8886. 0.5-10 keV. - PowerPoint PPT PresentationTRANSCRIPT
The afterglow and host galaxy of GRB 090205:
evidence for a Ly-α emitter at z = 4.65
Paolo D’Avanzo (INAF-Osservatorio Astronomico di Brera);
in collaboration with:
GRB 090205
0.5-10 keV
15-350 keV
T90 = 8.8 ± 1.8 s
No UVOT detection @ t-t0 = 92 s
Perri et al. 2009, GCN 8884Evans et al. 2009, GCN 8885Perri & Stratta, 2009, GCN 8891
Perri et al. 2009, GCN 8884Landsman & Perri, 2009, GCN 8893
Perri et al. 2009, GCN 8884Cummings et al. 2009, GCN 8886
GRB 090205
z =4.65(Thoene et al. 2009, GCN 8889; Fugazza et al. 2009, GCN 8892)
RAB ~ 22.3; IAB ~ 20.8(D’Avanzo et al. 2009;, GCN 8887)
F(t) t -α ; α ~ 1.4
t-t0 ~ 7 h
GRB 090205 afterglowtb,1 tb,2
α1
ГX,1
α2
ГX,2
α3
ГX,3
F(t) t -α
α1 ~ 1.4; α2 ~ -1.7; α3 ~ 1.2;
Time resolved X-ray spectroscopy: absorbed power-law withГX,1~ ГX,2~ ГX,3~ 2.0Galactic NH ~ 8 x 1020 cm-2 (no evidence for intrinsic absorbtion; NH < 3.5 x 1022 cm-2)
X-ray and optical AG explained within the standard FS model with νc,νm < νopt and νX
X-ray “brightnening” possibly due to energy injection into the FS by the engine
complex X-ray AG: brightening at ~T0+1000s and flaring
activity
GRB 090205: classification
Ch1 = 15-25 keVCh2 = 25-50 keVCh3 = 50-100 keVCh4 = 100-350 keV
Eγ,iso = (7.86 ± 1.21)x 1051 ergEp,i = 192 ± 85 keV
Lag(Ch2-Ch1): -15 +/- 867 ms Lag(Ch3-Ch2): 648 +/- 1336 ms Lag(Ch3-Ch1): 705 +/- 1326 ms
T90,rf = 1.6s
GRB 090205: classification
Ch1 = 15-25 keVCh2 = 25-50 keVCh3 = 50-100 keVCh4 = 100-350 keV
Eγ,iso = (7.86 ± 1.21)x 1051 ergEp,i = 192 ± 85 keV
Lag(Ch2-Ch1): -15 +/- 867 ms Lag(Ch3-Ch2): 648 +/- 1336 ms Lag(Ch3-Ch1): 705 +/- 1326 ms
Consistent with the
Ep,i - Eγ,iso
correlation (Amati et al.
2008)
GRB 090205
T90,rf = 1.6s
(Antonelli et al. 2009)
GRB 090205: evidence for a LAE (II)
0.4” offset with respect to the continuum(3 kpc @ z=4.65)
The same offset is found in imaging framesLy-α emission from the host galaxy
Farthest GRB host galaxy spectroscopically confirmed
Lyman-α emission line
GRB 090205: conclusions
• optical afterglow and host galaxy discovery; redshift determination
• complex X-ray AG: brightening at ~T0+1000s and flaring activity
•rest frame short duration (1.6s), but likely long, of massive stellar collapse origin
• the host galaxy is a LAE @ z = 4.65• SFR ~ 4.2 MSun/yr• young stellar population (< 150 Myr) • high metallicity (Z ≥ 0.27 ZSun) • farthest GRB HG spectroscopically confirmed
• GRBs as one of the most effective way, complementary to surveys, to study the high-z Universe
D’Avanzo et al., A&A submitted