VIRGO ITALY INFN Firenze Urbino Frascati Napoli Perugia

VIRGO ITALY - INFN Firenze - Urbino Frascati Napoli Perugia Pisa Roma F. Vetrano – Roma, Jun 1, 2005 FRANCE - CNRS ESPCI - Paris SMA - Lyon LAL - Orsay LAPP - Annecy OCA - Nice 1

Recycled interferometer lock • First experiments to implement a lock acquisition technique similar to LIGO • Early october 2004: development of a new technique, the variable finesse lock acquisition • First lock Oct 25 th (20 s) • First long lock Oct 26 th (40 min) • The variable finesse lock acquisition is a completely original approach: - Control all the degrees of freedom in a detuned point - Move the detector on the working point adiabatically F. Vetrano – Roma, Jun 1, 2005 2

Run sensitivities evolution C 4, recombined 7 W input power C 5, Recycled 0. 7 W input power F. Vetrano – Roma, Jun 1, 2005 3

Recycled interferometer noise Noise of C 5 run well understood C 5 Control noises oscillator phase noise F. Vetrano – Roma, Jun 1, 2005 4

Activities after C 5 Goals: 1/ Increase the stability and robustness of the recycled interferometer à Implement the wave-sensing control (or linear alignment) 2/ Increase the robustness in high seismicity conditions 3/ Study the C 5 noise sources 4/ Implement automatic procedures for ITF alignment and locking 5/ Improve the injection system (frequency noise and alignment) and give inputs for the new injection bench design F. Vetrano – Roma, Jun 1, 2005 5

The jumps • Start to be present continuously after C 5 • A meta-stable locking state Interferometer internal power (a. u. ) 1 sec • Jumps don’t permit science operations • Jumps often unlock the interferometer F. Vetrano – Roma, Jun 1, 2005 6

Planning - 1 • Close linear alignment • Improve inertial damping • make parallel tests to understand the jumps Jumps disappear Jumps do not disappear This is the case indeed… F. Vetrano – Roma, Jun 1, 2005 7

F. Vetrano – Roma, Jun 1, 2005 8

Planning - 2 • C 6 run: à Closing the linear alignment the high frequency noise should decrease • Change injection-bench and PR mirrors (Make several upgrades during the stop) • Restart the interferometer (x 10 power) • Decrease the known noise sources F. Vetrano – Roma, Jun 1, 2005 9

Status of the online analysis pipeline • h-Reconstruction – A test run of online calibration and reconstruction has been performed during C 5 run: it was possible to get calibrated data online. – Work is ongoing to extend the amount of data quality flags available online. – Reconstructed data can be sent to analysis farms; whitened/dfiltered data can also be produced and sent down the pipeline online. • Search for coalescing binaries events – The analysis farm can receive data from h-reconstruction, perform a parallel event search and return events. – Vetoes can currently be applied offline: work is ongoing to apply online internal vetoes (based on the signal channel) and external vetoes. • Search for burst events – Glitches in the data (jumps in the signal) can be detected online. – Other detection algorithms will be run in the same farm and with the same tools as the online CB search. Will be possibly test during one of the next engineering runs. F. Vetrano – Roma, Jun 1, 2005 10

Collaboration VIRGO – resonant bars • Scenario – The sensitivity of Virgo in recycled mode (C 5 run) was already compatible with a common Virgo – resonant bar run • The SNR for some classes of signals, like damped sines, was of the same order of magnitude – Two scientific subjects have been identified • On the coincident detection of burst signals • On stochastic background – Mo. U’s have been drafted and are being finalized – A White Paper describing the scientific objectives and the practical implementation of an Auriga – ROG – Virgo collaboration is ~ready • Next activities – The three experiments have agreed to perform a mock-data-challenge – The goal is to get ready for a joint run, as soon as Virgo sensitivity and stability allows it – Stretches of quiet data (engineering run data for Virgo, science data for resonant bar experiments) are being selected for the challenge – Simulated impulsive events and stochastic background noise will be summed to the real noise – Details are being worked out and will be included in the White Paper F. Vetrano – Roma, Jun 1, 2005 11

Collaboration with LIGO and LSC • Scenario – – LSC and Virgo are getting ready for a joint analysis Two parallel tasks: on impulsive (SN) and coalescing binaries signals An Mo. U has been written and is being signed Activity described in a white paper, organized in successive projects • Project 1 a – Exchange 3 h of simulated noise data + uncoherent CB and SN injections – Run of both analysis pipelines on both datasets – Global cross-check of the pipelines, sufficient for coincidence analysis ✔ [Completed] Two papers at GWDAW-9 workshop • Project 1 b – Exchange 24 h of simulated data with coherent CB and SN injections ✔ Global cross-check of the simulation engines [completed] – Test of the coincidence analysis – Possibly a test of coherent analysis – To be completed for Amaldi 6 [June 2005] • Project 2 – Exchange Xh of real (engineering) data with coherent injections – No time scale yet: linked to the progress of Virgo commissioning F. Vetrano – Roma, Jun 1, 2005 12

Richieste in corso d’anno F. Vetrano – Roma, Jun 1, 2005 13