title: Long gamma-ray bursts and core-collapse supernovae have different environments.
abstract: When massive stars exhaust their fuel, they collapse and often produce the extraordinarily bright explosions known as core-collapse supernovae. On occasion, this stellar collapse also powers an even more brilliant relativistic explosion known as a long-duration gamma-ray burst. One would then expect that these long gamma-ray bursts and core-collapse supernovae should be found in similar galactic environments. Here we show that this expectation is wrong. We find that the gamma-ray bursts are far more concentrated in the very brightest regions of their host galaxies than are the core-collapse supernovae. Furthermore, the host galaxies of the long gamma-ray bursts are significantly fainter and more irregular than the hosts of the core-collapse supernovae. Together these results suggest that long-duration gamma-ray bursts are associated with the most extremely massive stars and may be restricted to galaxies of limited chemical evolution. Our results directly imply that long gamma-ray bursts are relatively rare in galaxies such as our own Milky Way.
authors: Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, Maryland 21218, USA. fruchter@stsci.edu
authors: A S
authors: AS
authors: Fruchter
authors: A J
authors: AJ
authors: Levan
authors: L
authors: L
authors: Strolger
authors: P M
authors: PM
authors: Vreeswijk
authors: S E
authors: SE
authors: Thorsett
authors: D
authors: D
authors: Bersier
authors: I
authors: I
authors: Burud
authors: J M
authors: JM
authors: Castro Cerón
authors: A J
authors: AJ
authors: Castro-Tirado
authors: C
authors: C
authors: Conselice
authors: T
authors: T
authors: Dahlen
authors: H C
authors: HC
authors: Ferguson
authors: J P U
authors: JP
authors: Fynbo
authors: P M
authors: PM
authors: Garnavich
authors: R A
authors: RA
authors: Gibbons
authors: J
authors: J
authors: Gorosabel
authors: T R
authors: TR
authors: Gull
authors: J
authors: J
authors: Hjorth
authors: S T
authors: ST
authors: Holland
authors: C
authors: C
authors: Kouveliotou
authors: Z
authors: Z
authors: Levay
authors: M
authors: M
authors: Livio
authors: M R
authors: MR
authors: Metzger
authors: P E
authors: PE
authors: Nugent
authors: L
authors: L
authors: Petro
authors: E
authors: E
authors: Pian
authors: J E
authors: JE
authors: Rhoads
authors: A G
authors: AG
authors: Riess
authors: K C
authors: KC
authors: Sahu
authors: A
authors: A
authors: Smette
authors: N R
authors: NR
authors: Tanvir
authors: R A M J
authors: RA
authors: Wijers
authors: S E
authors: SE
authors: Woosley