17 research outputs found
Results of the search for inspiraling compact star binaries from TAMA300's observation in 2000-2004
We analyze the data of TAMA300 detector to search for gravitational waves
from inspiraling compact star binaries with masses of the component stars in
the range 1-3Msolar. In this analysis, 2705 hours of data, taken during the
years 2000-2004, are used for the event search. We combine the results of
different observation runs, and obtained a single upper limit on the rate of
the coalescence of compact binaries in our Galaxy of 20 per year at a 90%
confidence level. In this upper limit, the effect of various systematic errors
such like the uncertainty of the background estimation and the calibration of
the detector's sensitivity are included.Comment: 8 pages, 4 Postscript figures, uses revtex4.sty The author list was
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Observation results by the TAMA300 detector on gravitational wave bursts from stellar-core collapses
We present data-analysis schemes and results of observations with the TAMA300
gravitational-wave detector, targeting burst signals from stellar-core collapse
events. In analyses for burst gravitational waves, the detection and
fake-reduction schemes are different from well-investigated ones for a
chirp-wave analysis, because precise waveform templates are not available. We
used an excess-power filter for the extraction of gravitational-wave
candidates, and developed two methods for the reduction of fake events caused
by non-stationary noises of the detector. These analysis schemes were applied
to real data from the TAMA300 interferometric gravitational wave detector. As a
result, fake events were reduced by a factor of about 1000 in the best cases.
The resultant event candidates were interpreted from an astronomical viewpoint.
We set an upper limit of 2.2x10^3 events/sec on the burst gravitational-wave
event rate in our Galaxy with a confidence level of 90%. This work sets a
milestone and prospects on the search for burst gravitational waves, by
establishing an analysis scheme for the observation data from an
interferometric gravitational wave detector
Lokasi Baru Spesies Grup Oryzias Woworae (Adrianichthyidae) Di Sulawesi Tenggara [ New Localities of the Oryzias Woworae Species Group (Adrianichthyidae) ]
The Oryzias woworae species group, composed of O. asinua, O. wolasi, and O. woworae, is a group of the family Adrianichthyidae endemic to Sulawesi Tenggara (Southeast Sulawesi). Here, we report new localities of each of the three species in this group, which were collected during our field expeditions in 2014-2015. In total, six new localities were discovered throughout Sulawesi Tenggara, including Muna Island, suggesting that they may have wider species ranges than currently recognized. Some of the new localities were independent of the river systems of the known localities, suggesting that each species is genetically structured, and that the unit for conservation should be considered not as each species but as each local population