GRB 030329 was a

gamma-ray burst In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies. They are the most energetic and luminous electromagnetic events since the Big Bang. Bursts can last from ten millise ...

(GRB) that was detected on 29 March 2003 at 11:37 UTC. A gamma-ray burst is a highly luminous flash associated with an explosion in a distant galaxy and producing

gamma ray A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically ...

s, the most energetic form of

electromagnetic radiation In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. It includes radio waves, microwaves, infrared, (visible) li ...

, and often followed by a longer-lived "afterglow" emitted at longer wavelengths (

X-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation ...

optical Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultravio ...

infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...

, and

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmi ...

). GRB 030329 was the first burst whose afterglow definitively exhibited characteristics of a supernova, confirming the existence of a relationship between the two phenomena.

Observations

GRB 030329 was one of three gamma-ray bursts detected on 29 March 2003. The other two were labeled GRB 030329a and GRB 030329b. GRB 030329 was detected by multiple instruments onboard HETE at 11:37 UTC and lasted approximately 25 seconds. The burst's optical afterglow was first observed from Siding Spring Observatory less than two hours after the burst had been detected. The X-ray afterglow was first detected by

RXTE The Rossi X-ray Timing Explorer (RXTE) was a NASA satellite that observed the time variation of astronomical X-ray sources, named after physicist Bruno Rossi. The RXTE had three instruments — an All Sky Monitor, the High-Energy X-ray Timing E ...

approximately five hours after the burst. The radio afterglow was first detected by the

Very Large Array The Karl G. Jansky Very Large Array (VLA) is a centimeter-wavelength radio astronomy observatory located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~ west of Socorro. The VLA comprises twent ...

and, at the time of its discovery, was the brightest radio afterglow ever observed. The burst was located at a sky position of R.A. = , Dec. = and had a redshift of z = 0.1685, corresponding to a distance of 587 Mpc.

Supernova relation

GRB 030329's proximity to Earth enabled its afterglow to be studied in great detail. A

spectrum A spectrum (plural ''spectra'' or ''spectrums'') is a condition that is not limited to a specific set of values but can vary, without gaps, across a continuum. The word was first used scientifically in optics to describe the rainbow of colors ...

taken of the burst's optical afterglow on 6 April 2003 showed peaks at approximately 570 nm and 470 nm. This spectrum was reproduced by combining a power-law distribution with the spectrum from

SN 1998bw SN 1998bw was a rare broad-lined Type Ic gamma ray burst supernova detected on 26 April 1998 in the ESO 184-G82 spiral galaxy, which some astronomers believe may be an example of a collapsar (hypernova A hypernova (sometimes called a collap ...

. These supernova-like features continued to develop in the weeks after the initial burst. Optical observations taken at

Kitt Peak National Observatory The Kitt Peak National Observatory (KPNO) is a United States astronomical observatory located on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono Oʼodham Nation, west-southwest of Tucson, Arizona. With more than ...

on indicated that the burst's optical afterglow was brighter than a power-law decay would have predicted, a deviation that could have been explained by additional light from a supernova. On 10 April 2003,

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...

announced that GRB 030329 had provided the definitive link between gamma-ray bursts and supernovae. The supernova was later referred to as SN 2003dh.

Notes

{{reflist 030329 20030329 March 2003 events