EXPLORER is a cryogenic resonant-mass gravitational wave (GW) detector. It was installed at
in 1984 and it has been the first large-mass cryogenic GW antenna to perform
long-term continuous operation (since 1990).
EXPLORER is part of the international network of resonant-mass detectors
which includes ALLEGRO at the Louisiana State University, Baton Rouge,
AURIGA at the INFN Legnaro Laboratories, and NAUTILUS at the INFN Frascati
At the beginning of the year 2000, EXPLORER has been upgraded, with a
new small gap capacitive transducer giving high sensitivity on a much
larger bandwidth. The minimum detectable spectral amplitude is better
than 10-20 Hz-1/2 over a frequency band of 50 Hz around 900 Hz. The
corresponding sensitivity to short GW bursts is h=2 10-19. This sensitivity
should allow the detection of signal from gravitational collapses and
from coalescing and merging neutron stars/black holes binaries in our
Galaxy and in Local Group.