Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · astro-ph/0306403

On the Ly-alpha emission from gamma-ray burst host galaxies: evidence for low metallicities

J. P. U. Fynbo·P. Jakobsson·P. Moller·J. Hjorth·B. Thomsen·M. I. Andersen·A. S. Fruchter·J. Gorosabel·S. T. Holland·C. Ledoux·H. Pedersen·J. E. Rhoads·M. Weidinger·R. A. M. J. Wijers
View original source ↗Read source document ↗Export metadata ↓

Abstract

We report on the results of a search for Ly-alpha emission from the host galaxy of the z=2.140 GRB 011211 and other galaxies in its surrounding field. We detect Ly-alpha emission from the host as well as from six other galaxies in the field. The restframe equivalent width of the Ly-alpha line from the GRB 011211 host is about 21 AA. This is the fifth detection of Ly-alpha emission out of five possible detections from GRB host galaxies, strongly indicating that GRB hosts, at least at high redshifts, are Ly-alpha emitters. This is intriguing as only about 25% of the Lyman-Break selected galaxies at similar redshifts have Ly-alpha emission lines with restframe equivalent width larger than 20 AA. Possible explanations are i) a preference for GRB progenitors to be metal-poor as expected in the collapsar model, ii) an optical afterglow selection bias against dusty hosts, and iii) a higher fraction of Ly-alpha emitters at the faint end of the luminosity function for high-z galaxies. Of these, the current evidence seems to favour i).

Explore related subjects

astro-ph

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J. P. U. Fynbo, P. Jakobsson, P. Moller, J. Hjorth, B. Thomsen, M. I. Andersen, A. S. Fruchter, J. Gorosabel, S. T. Holland, C. Ledoux, H. Pedersen, J. E. Rhoads, M. Weidinger, R. A. M. J. Wijers. 2003-06-19. On the Ly-alpha emission from gamma-ray burst host galaxies: evidence for low metallicities. https://doi.org/10.1051/0004-6361%3A20030931

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Cosmic Conundrums with Quantum Corrections

Darh energy was discovered over 25 years ago and we do not have an explanation of it. Dark matter comprises 95% of matter in the universe and we still don't know what it is. The Webb telescope has been finding fully formed galaxies with massive black holes millions of times the mass of the sun in the early universe and we don't have any explanation. A quantum density limitation will be used to solve these and other outstanding problems.

astro-ph↗
arXiv2026

On binary pulsars and the force of gravity

The energy-momentum budget of the astrophysical systems can be studied by the exact local conservation equation derived by Landau and Lifshitz. We show that a similar equation is valid for the Einstein-Cartan gravity. We reanalyze a binary pulsar system using the Landau-Lifshitz conservation equation and show that the orbital period change rate can be completely understood as a curvature backreaction process. Taking into account the detailed theoretical and observational research of relativistic binary pulsar systems, especially the system of Hulse and Taylor, we conclude that general relativity and astrophysical observations rule out the existence of gravitational radiation. We comment upon the LIGO GW events and their alternative explanation, as well as the recent pulsar timing arrays data.

astro-ph↗
arXiv2026

Oscillation frequencies and mode lifetimes in alpha Centauri A

We analyse our recently-published velocity measurements of alpha Cen A (Butler et al. 2004). After adjusting the weights on a night-by-night basis in order to optimize the window function to minimize sidelobes, we extract 42 oscillation frequencies with l=0 to 3 and measure the large and small frequency separations. We give fitted relations to these frequencies that can be compared with theoretical models and conclude that the observed scatter about these fits is due to the finite lifetimes of the oscillation modes. We estimate the mode lifetimes to be 1-2 d, substantially shorter than in the Sun.

astro-ph↗