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Enabling High Grayscale Resolution Displays and Accurate Response Time Measurements on Conventional Computers
Published on: February 29, 2012
GRB 090423 at a redshift of z approximately 8.1
R Salvaterra1, M Della Valle, S Campana
1INAF, Osservatorio Astronomico di Brera, Via E. Bianchi 46, 23807 Merate (LC), Italy. salvaterra@mib.infn.it
Nature
|October 30, 2009
Summary
Astronomers detected a gamma-ray burst (GRB) at a record redshift of z = 8.1. This early universe GRB suggests similar stellar explosion mechanisms existed shortly after the Big Bang.
Area of Science:
- Cosmology
- Astrophysics
- High-energy astrophysics
Background:
- Gamma-ray bursts (GRBs) originate from massive stellar explosions.
- GRB afterglows are detectable at cosmological distances due to their optical brightness.
- Previous highest redshift for a GRB was z = 6.7.
Purpose of the Study:
- To report the observation of GRB 090423.
- To measure the redshift of GRB 090423 using near-infrared spectroscopy.
- To investigate early universe phenomena through GRB observations.
Main Methods:
- Observations of GRB 090423.
- Near-infrared spectroscopic measurement of redshift.
Main Results:
- Redshift of GRB 090423 measured at z = 8.1 (+0.1/-0.3).
- This GRB occurred approximately 600 million years after the Big Bang.
- GRB properties are comparable to those at lower redshifts.
Conclusions:
- The findings push the frontier of observable GRBs to higher redshifts.
- Early universe GRBs share similar properties with later ones, indicating consistent progenitor mechanisms.
- This suggests that the processes forming GRBs were established very early in cosmic history.
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