Burst signals have time duration small compared
to the observation time.
They are emitted, for example, in the collapse of a star, leading
to a supernova explosion, in the final stage of the coalescence of
two collapsed objects (two neutron stars, two black holes, or one
of each), or in case massive black holes eat surrounding
objects.
The sensitivity of the detectors
to burst signals is a function of its noise
spectral amplitude (1/sqrt(Hz)) and bandwidth.
It may be expressed in terms of effective
temperature [K] or in terms of h
the dimensionless amplitude, for a 1 ms burst. On the detector sensitivity to
bursts
The figures show an example of functioning
of Explorer during June
2001
and of Nautilus during July
2001
The figure shows the OPERATION TIMES of the
two detectors, Explorer -896 days- (blue) and Nautilus -766 days-
(green)
from Jan 1997 to 21 May 2002
Next figures show the sensitivities to bursts
of the two detectors, Explorer and Nautilus
from Jan
1997 to Dec 2000
Due to the weakness of the signals the use of suitable data
analysis tecniques is required to increase the Signal to noise
ratio. We use filters matched to a delta signal
On the matched filter for
g.w. bursts
Various papers have been done to study the filter performances,
using the detectors noise and adding delta-like signals to the
noise. Here you can find some papers on:
The fast matched filter for
g.w. data analysis:characteristics and applications (Nuovo
Cimento C, 1997)
Time dispersion and efficiency of
detection for signals in g.w. experiments (PRD 62,2000)
Linear filtering for
the detection of short bursts of g. r. ( S. D' Antonio,4th Amaldi Conf.,
Perth,2001- CQG 19,7, 2002)
The main point of the burst detection is the need for coincidence
analysis between two or more detectors. Here you can find some
papers on:
``Study of coincidences between
the g.w. detectors Explorer and Nautilus in the year 2001''
(CQG 19 (2002) 5449-5463 and gr-qc/0210053)
Search for gravitational radiation
with the Allegro and Explorer detectors (PRD 59, 122001
(1999))
Search for Coincident
Excitation of the widely Spaced Resonant G.W. detectors Explorer,
Nautilus and Niobe (AstroParticle Physics 10,1 (1999))
First search for gravitational wave
bursts with a network of detectors (PRL 85, 5046-5050, 2000 )
Initial operation of the
International gravitational event collaboration (International
Journal of Mod. Phys. D,9 (2000))
( Visit the IGEC web site!
)
On upper limits for g.w.
radiation (AstroParticle Physics 16, 441-450 (2002))
Study of coincidences between
resonant g.w. detectors (CQG 18,2,243-251, 2001)
Coincidence analysis in g.w. experiments
( P. Astone et al,4th Amaldi Conf., Perth,2001- CQG 19,7 (2002)
Search for gravitational wave bursts by the network of resonant detectors
(presented by G. Prodi at the 4th Amaldi Conf., Perth,2001- CQG 19,7,2002)
Background estimation in a
gravitational wave experiment (International Journal of Mod.
Phys. D,9 (2000))
