The Virgo status Amico, P; Alshourbagy, M; Aoudia, S ...
Classical and Quantum Gravity,
10/2006, Volume:
23, Issue:
19
Journal Article, Conference Proceeding
Peer reviewed
We report on the status of the Virgo detector, under commissioning. We will focus on the last year's activity. The two commissioning runs performed during 2005 allowed us to reach a sensitivity of
h
...∼ 6 × 10
−22
. The data obtained during the runs were used to test a few data analysis algorithms, namely coalescing binaries and burst searches. The main improvements made on the detector during this year will be described, as well as the plans and activities foreseen in the coming years.
Properties of seismic noise at the Virgo site Acernese, F; Amico, P; Arnaud, N ...
Classical and Quantum Gravity,
03/2004, Volume:
21, Issue:
5
Journal Article, Conference Proceeding
Virgo is a laser Michelson interferometer with 3-km long Fabry-Perot in the arms, aiming at the detection of gravitational waves emitted by astrophysical sources in the frequency band from 10 Hz to ...few kHz. The core of the detector, the central interferometer, was installed first. It is a recycled Michelson interferometer, with 6-m long arms, obtained by replacing the 3-km long Fabry- Perot cavities with high reflectivity mirrors and using the same components designed for Virgo. In particular all the mirrors of the interferometer are suspended from the seismic isolators that represent the main unique characteristic of the Virgo detector. The interferometer has been controlled by means of a fully digital control system, capable of monitoring and controlling the relative position of the mirrors with an accuracy of 10 exp -12 m. The best displacement sensitivity was 10 exp -13 m/sq rt Hz at 10 Hz and 8 x 10 exp -17 m/sq rt Hz above 1 kHz. This article describes the detector configuration, the tests performed in view of commissioning the full detector and the main results obtained.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The mirrors of interferometric detectors of gravitational waves (GW) are suspended in order to be isolated from external disturbances. A local control system able to keep them correctly aligned and ...to damp the angular modes of the suspension is necessary. In this paper we present the solution adopted for Virgo based on a CCD camera sensor and on digital controls. With this solution the mirrors are kept aligned at the level of less than 1 μrad
rms, enough to lock the interferometer and start the automatic alignment system.
Full text
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
8.
The VIRGO injection system Bondu, F; Brillet, A; Cleva, F ...
Classical and quantum gravity,
04/2002, Volume:
19, Issue:
7
Journal Article
Operation of the central portion of Virgo as a simple 6 m Michelson interferometer has given the first demonstration of the possibility to control an interferometer suspended from Virgo full scale ...multistage seismic attenuators using information derived from the interferometer locking signal. A special role in the control is played by the first stage of these suspensions, an inverted pendulum: besides its seismic preisolation action, this stage has positioning dynamics of several mm, and it allows to exert a very low frequency control at the upper level of the suspension using the interferometer fringe signal. The application of this feedback to the top-stage of the suspension allows corrections of drifts, such as tidal ones, at a stage of the suspension where a large dynamic range in displacements is available, without introducing noise at the level of the mirror, resulting in a significant reduction of the lock keeping force applied directly on the mirror at the lowest stage of the attenuator.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
