The Extinction Towards the GRB970228 Field

Abstract

We determine the local galactic extinction towards the field of gamma-ray burst GRB970228 using a variety of methods. We develop a maximum likelihood method for measuring the extinction by comparing galaxy counts in the field of interest to those in a field of known extinction, and apply this method to the GRB970228 field. We also measure the extinction by comparing the observed stellar spectral energy distributions of stars in the GRB970228 field to the spectral energy distribution of library spectra of the same spectral type. Finally we estimate the extinction using the Balmer emission line ratios of a galaxy in the GRB970228 field, and the neutral hydrogen column density and amount of infrared dust emission toward this field. Combining the results of these methods, we find a best-fit galactic extinction in the optical of $A_V=1.19_{-0.17}^{+0.10}$, which implies a a substantial dimming and change of the spectral slope of the intrinsic GRB970228 afterglow.

22 pages, including 7 figures. Submitted to ApJ

References in corpus (6)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• The optical counterpart to gamma-ray burst GRB970228 observed using the Hubble Space Telescope
• The Fading Optical Counterpart of GRB~970228, Six Months and One Year Later
• Spectral Properties of the Prompt X-ray emission and Afterglow from the Gamma-Ray Burst of 28 February 1997
• A Constant Clustering Amplitude for Faint Galaxies?
• Galactic Extinction from Colors and Counts of Field Galaxies in WFPC2 Frames: An Application to GRB 970228

Cited by in corpus (8)

• Evidence for a supernova in reanalyzed optical and near-infrared images of GRB970228
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• Neutrino, Neutron, and Cosmic Ray Production in the External Shock Model of Gamma Ray Bursts
• On the optical and X-ray afterglows of gamma ray bursts
• The redshift and the ordinary host galaxy of GRB 970228
• A tale of two GRB-SNe at a common redshift of z = 0.54
• The clustering of the luminosities of optical afterglows of long Gamma Ray Bursts
• Gamma Ray Burst Host Galaxies Have `Normal' Luminosities