1. The VIRGO DATA ANALYSIS Fulvio Ricci
Department of Physics, University of Rome La Sapienza, Italy
&
I.N.F.N. - Sezione di Roma
CNRS (France): Lapp-Annecy, LAL-Orsay, SMA-Lyon, Obs-Nice and EPSCI-Paris
INFN (Italy): Sezioni di Firenze/Urbino, LNF-Frascati, Perugia, Pisa
and Roma-La Sapienza
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TYPICAL RAW DATA FRAME (1 second)
Sub-System Number of Signals Compressed Size Size
of the Interf (MByte) (MBbyte)
Environment
Injection
Suspension
Detection
Global Control
Calibration
Total +
Trend Data signals For each ADC, a trend SMS, with the following signals: min, max,
+ mean, r.m.s. , slope max, c2 fit
Frame Header 1 Structure FrameH General information: GPS time,
Total
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Raw data are transferred via network to Bologna and to Lyon
At presents the transfer rate is 1 half the production rate
Automatic procedure developed by EGO (
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Storage Needs
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Signal Extraction and Data Analysis
Basic Software used by VIRGO
cernlib, Root_v , lam_pi v7.0.3, fftw v3.0.1
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6. Data Analysis Organization in VIRGO
VIRGO Data Analysis Coordinator
(F. Ricci,
Physics groups and coordinators:
h reconstruction
(F. Marion,
Bursts
(P. Hello,
Binary Coalescent
(A. Vicerè,
Pulsar Search
(S. Frasca,
Stochastic Background
(G. Cella,
Noise Analysis
(J. Y. Vinet,
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Computational load: some figures of merit
CONTINUOUS SIGNALS >1 TeraFlops substained
CHIRPS ~ 300 Gflops
COHERENT NETWORK ANALYSIS for CHIRPS >1 TeraFlops
Other search classes have negligible impact
Computational power and storage are structured in classes and hierarchically distributed in the computer centers in France (Lyon) and in Italy (Bologna) plus in the Virgo laboratories of the collaboration.
Data production site Ego- Cascina;
Tier Lyon – IN2P3,
Bologna - CNAF/INFN
Tiers 2 Roma 1 (Continuous signals )
Napoli
Use of GRID technology
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Efficiency of about 90%
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INFN Tier1-Bologna)
Computation in 2004 and 2005
In principle we have to balance the use of computational resources in Bologna and in Lyon
> KSpecInt2K*hour > KSpecInt2K*hour
Storage:
17 Tbyte of data (from E0 to C5) stored on disks, asked up to 20 Tbyte for 2004
Data flow 3 Mbytes/sec (transfer performed by a DELL 1GHz)
Automatic procedures for the data transfer (EGO --> Bologna --> Lyon)
Preprocessing:
1 machine (DELL 2.2 Ghz) Used also for the first data exchange exercise between LIGO and Virgo
GRID Farm:
14 machines (12 WN, 1 SE and 1 CE) + 1 UI and 1 PBS server common for all the experiments.
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10. VIRGO - resonant detectors data exchange
VIRGO-ROG MOU for data exchange already approved
VIRGO-AURIGA MOU for data exchange under preparation
Discussion and meetings take place already between VIRGO and AURIGA and ROG independently.
We plan to have the first joint meeting for defining the VIRGO/bar conicidence experiment on January 26th, 2005
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C4 run: ITF sensitivity
C3 (April 2004)
C4 (June 2004)
2.5 · 10-20
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13. C5 Recycled Interferometer
Hz -1/2
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C5 run vs LIGO history
‘without power recycling’
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Technical aspects of the Data Exchange: the use of Grid tools and the LSC - VIRGO case
What is LDR (Lightweight Data Replicator)?
It is a software tool developed by LIGO computer scientists (Scott Koranda and coll.) to allow copy/transfer/replication of large data sets among different sites. It is used for replication of data from LIGO scientific runs
Which are its building blocks?
GridFTP for fast rate data transfer;
Globus Replica Location Service (RLS) for file location tracking;
MySQL database for storing metadata;
Globus Security Infrastructure (GSI) for client/server authentication.
At present LDR is under test by the VIRGO - Napoli
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