Swift's Key Discoveries
Swift discoveries are answering key questions on gamma-ray
bursts (GRBs). They have confirmed the promise of GRBs as unique
probes of the high-redshift Universe and provided key information on
the birth of black holes. Rapid, uniform observations on broad time
scales make Swift the most capable GRB observatory ever. The
XRT detects 88% of all GRB X-ray afterglows and 40% of all
Swift is a multi-purpose observatory that has evolved into
a major general observing facility. Swift has observed
supernovae, cataclysmic variables, active galactic nuclei, galactic
transients, active stars, comets, and many other phenomena. Target of
opportunity observations from the astrophysics community account for
55% of Swift's observing time
Some of Swift's key discoveries (as of Feb 2010) are
- Swift detected GRB 090423, the most distant known
spectroscopically confirmed object in the Universe at z =
- Swift has measured the metallicity of star-forming
regions at high redshift (z > 5) using GRBs.
- UVOT and XRT have provided arcsecond positions for short-hard
GRBs that have allowed their host galaxies to be identified.
This has strengthened the case for the short bursts being due to
merging binary neutron stars.
- Swift has discovered a previously-unknown class of
long-soft GRBs that have no associated supernova.
- XRT has discovered X-ray flares in GRBs and found that in
some cases the X-ray afterglow decays very slowly. This
suggests that the central engine remains active for minutes to
hours after the burst.
- UVOT has obtained unique ultraviolet light curve for a large
number of supernovae of all types.
- XRT has observed the X-ray flash from the shock breakout
of a supernova.
- BAT has performed the deepest hard X/-ray survey to date
finding >400 AGN and absorbed Seyfert 2 galaxies.
- Swift, in conjunction with XMM-Newton, has found
the best evidence for an intermediate mass black hole in the
galaxy NGC 5408.
- Swift, in conjunction with Fermi, discovered two
soft gamma-ray repeaters: SGR 0501+4516 and SGR 0415-5729.
- Swift obtained unique ultraviolet and X-ray data
on comets Lulin and 8P/Tuttle, including observing the Deep