1 / 12

The afterglow and host galaxy of GRB 090205: evidence for a Ly- α emitter at z = 4.65

This study presents evidence for a Lyman-α emitter at redshift z=4.65 associated with the afterglow and host galaxy of GRB 090205. The analysis includes X-ray and optical observations, providing insights into the properties of the host galaxy, such as star formation rate, metallicity, and stellar population age.

archiesmart
Download Presentation

The afterglow and host galaxy of GRB 090205: evidence for a Ly- α emitter at z = 4.65

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 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:

  2. GRB 090205 15-350 keV T90 = 8.8 ± 1.8 s Perri et al. 2009, GCN 8884 Cummings et al. 2009, GCN 8886 0.5-10 keV Perri et al. 2009, GCN 8884 Evans et al. 2009, GCN 8885 Perri & Stratta, 2009, GCN 8891 No UVOT detection @ t-t0 = 92 s Perri et al. 2009, GCN 8884 Landsman & Perri, 2009, GCN 8893

  3. GRB 090205 t-t0 ~ 7 h RAB~ 22.3; IAB~ 20.8 (D’Avanzo et al. 2009;, GCN 8887) F(t) t -α; α ~ 1.4

  4. GRB 090205 t-t0 ~ 7 h RAB~ 22.3; IAB~ 20.8 (D’Avanzo et al. 2009;, GCN 8887) F(t) t -α; α ~ 1.4 z =4.65 (Thoene et al. 2009, GCN 8889; Fugazza et al. 2009, GCN 8892)

  5. GRB 090205 afterglow tb,1 tb,2 complex X-ray AG: brightening at ~T0+1000s and flaring activity α2 ГX,2 F(t) t -α α1 ~ 1.4; α2 ~ -1.7; α3 ~ 1.2; Time resolved X-ray spectroscopy: absorbed power-law with ГX,1~ ГX,2~ ГX,3~ 2.0 Galactic NH ~ 8 x 1020 cm-2 (no evidence for intrinsic absorbtion; NH < 3.5 x 1022 cm-2) α1 ГX,1 α3 ГX,3 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

  6. GRB 090205: classification T90,rf = 1.6s Ch1 = 15-25 keV Ch2 = 25-50 keV Ch3 = 50-100 keV Ch4 = 100-350 keV Lag(Ch2-Ch1): -15 +/- 867 ms Lag(Ch3-Ch2): 648 +/- 1336 ms Lag(Ch3-Ch1): 705 +/- 1326 ms Eγ,iso = (7.86 ± 1.21)x 1051 erg Ep,i = 192 ± 85 keV

  7. GRB 090205: classification T90,rf = 1.6s Ch1 = 15-25 keV Ch2 = 25-50 keV Ch3 = 50-100 keV Ch4 = 100-350 keV Lag(Ch2-Ch1): -15 +/- 867 ms Lag(Ch3-Ch2): 648 +/- 1336 ms Lag(Ch3-Ch1): 705 +/- 1326 ms Eγ,iso = (7.86 ± 1.21)x 1051 erg Ep,i = 192 ± 85 keV (Antonelli et al. 2009) GRB 090205 Consistent with the Ep,i - Eγ,iso correlation (Amati et al. 2008)

  8. GRB 090205: evidence for a LAE (I)

  9. GRB 090205: evidence for a LAE (I) Lyman-α emission line

  10. GRB 090205: evidence for a LAE (II) Lyman-α emission line 0.4” offset with respect to the continuum (3 kpc @ z=4.65) The same offset is found in imaging frames Ly-α emission from the host galaxy Farthest GRB host galaxy spectroscopically confirmed

  11. GRB 090205 host galaxy LLy-α~ 0.6-0.7 L* SFR ~ 4.2 MSun/yr Z ≥ 0.27 ZSun τ < 150 Myr M* < 150 MSun

  12. 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

More Related