Event type | Gamma-ray burst ![]() |
---|---|
Constellation | Leo ![]() |
Right ascension | 10h 44m 49.95957s |
Declination | +21° 31′ 17.4375″ |
Distance | 587,000,000 pc (1.91×109 ly) |
Other designations | GRB 030329A, GRB 030329, SN 2003dh |
GRB 030329 was a gamma-ray burst (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 rays, the most energetic form of electromagnetic radiation, and often followed by a longer-lived "afterglow" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, and radio). GRB 030329 was the first burst whose afterglow definitively exhibited characteristics of a supernova, confirming the existence of a relationship between the two phenomena.
GRB 030329 was one of three gamma-ray bursts detected on 29 March 2003. The other two were labeled GRB 030329a [1] and GRB 030329b. [2] GRB 030329 was detected by multiple instruments onboard HETE at 11:37 UTC and lasted approximately 25 seconds. [3] The burst's optical afterglow was first observed from Siding Spring Observatory less than two hours after the burst had been detected. [4] The X-ray afterglow was first detected by RXTE approximately five hours after the burst. [5] The radio afterglow was first detected by the Very Large Array and, at the time of its discovery, was the brightest radio afterglow ever observed. [6] The burst was located at a sky position of R.A. = 10h 44m 49.95957s, Dec. = +21° 31′ 17.4375″ and had a redshift of z = 0.1685, corresponding to a distance of 587 Mpc. [7]
GRB 030329's proximity to Earth enabled its afterglow to be studied in great detail. A spectrum 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. [8] These supernova-like features continued to develop in the weeks after the initial burst. [9] Optical observations taken at Kitt Peak National Observatory 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. [10] On 10 April 2003, NASA announced that GRB 030329 had provided the definitive link between gamma-ray bursts and supernovae. [11] The supernova was later referred to as SN 2003dh. [12]