The commissioning of Virgo and

GEO

The link with N5-WG1

G.Losurdo – INFN Florence

H.Grote – AEI Hannover

on behalf of N5-WG1

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 2/19

GW detection in Europe

Interferometers

GEO600 – D/UKHannover

Virgo – F/I/NLCascina (PI), EGO

Resonant detectors

Auriga – ILegnaro (PD)

Explorer – ICERN

Nautilus – IFrascati (RM)

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 3/19

Detector plans

2006 2007

LSC-Virgo MoUfor data exchangeand joint analysis

RunCommissioning

S5 Commissioning

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 4/19

GEO600 in LSC-S5

Instrumental duty cycle: 94.3 % Science time duty cycle: 91.0 % Longest lock: 102 hrs Good stationarity

Inst

. du

ty c

ycle

[%

]

May 1 - Oct 15: 168 days

days

Histogram of sensitivities (BLRMS 555-565Hz) May-September

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 5/19

After S5

Continue commissioning (at least until spring 2007) to:

improve sensitivity allow long term operation understand better the noise sources

GEO runs in overnight/weekend mode since Oct 15

What next?

Re-join S5 until its end or commissioning until end 2007?

Stay on run during 2008

Sequential upgrades starting 2009

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 6/19

Virgo last year

Work on several issues aimed to – improve robustness– improve sensitivity– understand fully the noise

Weekly Science Runs (WSR): detector taking data during some weekends. Nine WSRs held so far

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 7/19

Detector progress

Main actions Reduction of longitudinal control

noise Reduction of scattered light

effects Improvements of the

interferometer controls

WSR 1 – Sep 06WSR 8 – Feb 07

SENSITIVITY

WSR 5 – Nov 06WSR 7 – Jan 07

GAUSSIANITY

STABILITY

55.5 hrs lock

interferometer power

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 8/19

WSRn: towards S5

WSR # date duty cycle (% locked)

1 Sep 8-11, 2006 90

2 Sep 22-25, 2006 65

3 Oct 6-9, 2006 cancelled

4 Oct 13-16, 2006 cancelled

5 Nov 10-13, 2006 65

6 Dec 1-4, 2006 80

7 Jan 12-15, 2007 76

8 Feb 9-12, 2007 94

9 Feb 17-19, 2007 100

Commissioning going onPlanned start of the long science run: May 18th

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 9/19

Noise hunting

Noise not completely understod.

Noise hunting going on on both detectors

Collaboration going on in WG1 to face common problems

mark the gap between the understood noise and the measured one

The role of N5-WG1

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 11/19

N5-WG1 - the mission

Objectives

– To speed up the commissioning and the characterization of Virgo and GEO by means of a deeper collaboration between the two teams

– To develop common methods of characterization of interferometric GW detectors to be applied to Virgo and GEO

– To suggest short term improvements of the existing interferometric detectors on the base of the commissioning experience

Activity:

– face-to-face meetings: detectors status overview, commissioning issues, “hot topic”

– parallel projects: joint work on specific commissioning topics performed by smaller groups

– visits to labs and detector sites, control room sessions

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 12/19

N5-WG1 – the group

GEO600

A.FreiseS.HildH.Grote (co-chair)G.DegaillaixH.LueckJ.Smith

Virgo

M.BarsugliaH. HeitmannP.La PennaG.Losurdo (co-chair) E.Tournefier

Bar detectors

L.TaffarelloM.Visco

Many others attending and giving talks…

P.Ajith, L.Barsotti, V.Dattilo, M.Evans, I.Fiori, R.Gouaty, R.Flaminio, V.Iafolla, M.Mantovani, J.Marque, G.Mayer, G.Vajente, B.Willke, J.P.Zendri,…

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 13/19

N5-WG1 - Meetings held so farWG1 meetings

1st meeting, Cascina, Jul 7-8 2004 2nd meeting, Hannover, Sep 23-24 2004 3rd meeting, Cascina, Jan 24-26 2005 4th meeting, Hannover, April 7-8 2005 5th meeting, Telecon, Jul 14 2005 6th meeting, Perugia, Sep19-20 2005 7th meeting, Hannover, Dec 12 2005 8th meeting, Frascati, Mar 20-21 2006 9th meeting, Potsdam, Jul 21-22 200610th meeting, Cascina, Nov 13-14 200611th meeting, Hannover, Jan 23-24, 2007

12th meeting, CERN, Mar 29-30, 2007

The windmills project

1st telecon, May 12, 2005Team meeting, Cascina, 7-9 June 2005Seismic survey, GEO600 site, July 25-29 2005 2nd telecon, August 25, 2005

The beam centering project

1st report, Napoli-Cascina, June 10-14, 2005

The alignment simulation project

1st meeting, Birmingham, August 2006

The joint noise hunting project

1st report, Cascina, September 11-22 20062nd report, Cascina, October 16-20 20063rd report, Cascina, November 13-17 20064th report, Cascina, January 14-19 2007

5th report, Cascina, March 2007

PARALLEL PROJECTS

envi

ronm

enta

l

noise

stud

ies

inte

rfero

met

er

cont

rols

sens

itivity

stud

ies

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 14/19

Common problems: stray light

Stray light (or scattered light) is an important noise source for all of the interferometric detectors, and is hard to foresee and modelize

Extremely small amounts of light power can cause significant problems

Diagnostics:– Search of spurious beams– Acoustic noise injections– Tapping/hammering tests

Noise reduction techniques:– New optical layouts for auxiliary beams– Larger/higher quality optics– AR-coated windows on photodiodes– Beam dumps

Typical topic for WG1

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 15/19

The joint noise hunting project

Common noise investigations

– Virgo alignment noise projections– Virgo laser power noise investigations – GEO noise transfer functions simulation– General noise hunting at both sites– Knowledge exchange

A 9 months post-doc fellowship granted.

J.Smith (GEO) spent 25% of time at Virgo site

Common algos/Software exchange

– GEO algo for glitch parameterization implemented at Virgo

– GEO data viewer used at Virgo to listen to “dark fringe music” and for off-line analysis of data

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 16/19

The joint noise hunting project

How much is the alignment noise coupled with the GW channel?

Answer the questions by measuring noise projections

Method frequently discussed in WG1, now widely used on both detectors

J. Smith - G. Vajente

Virgo sensitivity

Alignment noisecontributions

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 17/19

The joint noise hunting project

GEO glitch monitor available at Virgo. Precious “commissioning oriented” tool for understanding detector noise

― data quality

― detector noise characterization

― vetoing

Every point is a glitch: an excess of power for some short period of time (tens of ms) and a narrow frequency band (tens of Hz)

HACR at VirgoJ. Smith - G. Vajente

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 18/19

The Windmills project

Costruction of two windmills stations near Virgo proposed. Concern for seismic disturbance

The wind park next to GEO600: chance to study the windmills seismic wave field in a soft soil similar to the Virgo one. – Seismic survey on GEO600 site using two stations run in

coincidence– A model of noise spectral composition and soil attenuation was

done and used to predict effects of the wind parks at Virgo. A safety distance of 5km from Virgo buildings was defined.

Positive reaction of both windmill companies, which modified projects layout to comply with our request.

Joint VIRGO-GEO600 document: VIR-NOT-PIS-1390-317 (I.Fiori

L.Giordano S.Hild G.Losurdo E.Marchetti G.Mayer F.Paoletti)

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 19/19

Conclusion

The networking activity N5-WG1 is having a real impact on the commissioning of Virgo and GEO600

WG1: intense activity linked to the commissioning of Virgo and GEO– Frequent face-to-face meetings– Parallel projects on defined topics– Joint noise hunting effort

Today: a real collaboration among a group of young physicists has been established

Tomorrow: the grown-up WG1 fellows may continue to collaborate and lead the effort for a new EUROPEAN detector

Spare slides

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 21/19

WG1: 4-years execution plan

Annual report

Recommandations report for short term improvements

GEO/Virgo joint noise characterization

YEAR 407-08

Annual report

GEO/Virgo joint noise characterization

Implementation of common characterization algorithms

YEAR 306-07

Annual report

Recommandations report for short term improvements

GEO/Virgo joint noise characterization

Development of common characterization algorithms

YEAR 205-06

Annual reportWorking group set-up

GEO/Virgo noise sources comparison

YEAR 104-05

DELIVERABLESMILESTONES

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 22/19

The beam centering project

Centering of beam used for wavefront sensing on the quadrants is essential for the robustness of the alignment system

Virgo quadrants are centered with a low bandwidth (<0.3 Hz) control– Not enough to reduce rms considerably– Noisy system

GEO uses a commercial galvanometer scanner with custom mechanics and electronics.

Succesfully tested on Virgo: very good suppression of beam fluctuations

Galvo offGalvo on

R.De Rosa, L. Di Fiore, H.Grote, H.Heitmann, J.Marque,

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 23/19

The alignment optimization project

Sensing matrix optimization– Use the distribution of the matrix’ row vectors in the system's

parameter space. Compute the separation of the diode signals in the space of the mirror angular movements.

Controllability:– Study of the dependence of the controllability of a simple system (a

FP cavity using the Ward and the Anderson technique) on the parameters of the optical readout in order to validate and check the performance the chosen test method

Alignment noise propagation in Virgo under study

VIRGO configuration: Result of the study on the controllability on a complex configuration as the VIRGO alignment system. The minimum separation between the 'best' sub-set of signal vectors is shown as a function of Gouy and demodulation phase (for the NE diodes). The chosen alignment control system can thus control all the required degrees of freedom and it can improved by tuning the parameters of the optical readouts.

A.Freise, M.Mantovani

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 24/19

LIGO

Commissioning started in 1999.Design sensitivity achieved.

Detector technology demonstrated

Commissioning started in 1999.Design sensitivity achieved.

Detector technology demonstrated

Long commissionin

g needed

Challenging… but feasible

ILIAS Annual Meeting - Chambery, Feb. 27th, 2007 G.Losurdo – INFN Firenze 25/19

Virgo, GEO, LIGOs