JRA3 STREGA - Introduction

Geppo CagnoliIGR – University of Glasgow

ILIAS-GW Meeting, Orsay, 5th-6th Nov 2004

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 2

10 0 10 910 6 [Hz]10 3

Bars and

Spheres

RF CavitiesInterferometers

Overview on GW detection

The expected strain of space is 10-22 Hz-1/2 or lower

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 3

Ultimate limits on GW detection

All the detectors are mainly limited by thermal noise

that causes fluctuations on position and shape of the

test masses Interferometers: thermal noise in mirrors and in suspension fibres

Bars/Spheres: thermal noise in the resonant elements

RF cavities: thermal noise in the cavity walls and in the e.m. field

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 4

STREGA Mission

Lower thermal noise 10 times with respect to the

second generation detectors

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 5

IFOS TH.NS BAND

Detectors Generations

1 10 100 1k 10kFrequency [Hz]

10 -22

10 -23

10 -24

10 -25

10 -19

10 -20

10 -21

h

[ H

z –1

/2 ]

GEO600

LIGOVIRGO

AURIGANAUTILUS

1ST GENERATION

FOR IFOS•STEEL SUSPENSIONS (APART GEO600)•ROOM TEMPERATURE

FOR RESONATORS•ALUMINIUM CYLINDERS•100mK < T < 4K

LIGO SCIENTIFIC RUN 3POSSIBLE DETECTION OF NS/NS MERGING

WITHIN THE LOCAL GROUPDISTANCE < 1.8 MPc

1ST GENERATION SHOULD REACH THE VIRGO CLUSTER AT 17MPc

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 6

Detectors Generations

1 10 100 1k 10kFrequency [Hz]

10 -22

10 -23

10 -24

10 -25

10 -19

10 -20

10 -21

h

[ H

z –1

/2 ]

GEO600

LIGOVIRGO

AURIGANAUTILUS

1ST GENERATION

FOR IFOS•STEEL SUSPENSIONS (APART GEO600)•ROOM TEMPERATURE

FOR RESONATORS•ALUMINIUM CYLINDERS•100mK < T < 4K

2ND GENERATION

FOR IFOS•SILICA SUSPENSIONS•HIGHER LASER POWER•ROOM TEMPERATURE

FOR RESONATORS•CuAl SPHERES• T < 100mK•BETTER READOUT

RF CAVITIES•1ST DETECTORSAD. LIGO

AD. VIRGO

MiniGRAIL

PACO

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 7

Detectors Generations

1 10 100 1k 10kFrequency [Hz]

10 -22

10 -23

10 -24

10 -25

10 -19

10 -20

10 -21

h

[ H

z –1

/2 ]

GEO600

LIGOVIRGO

AURIGANAUTILUS

1ST GENERATION

FOR IFOS•STEEL SUSPENSIONS (APART GEO600)•ROOM TEMPERATURE

FOR RESONATORS•ALUMINIUM CYLINDERS•100mK < T < 4K

2ND GENERATION

FOR IFOS•SILICA SUSPENSIONS•HIGHER LASER POWER•ROOM TEMPERATURE

FOR RESONATORS•CuAl SPHERES• T < 100mK•BETTER READOUT

RF CAVITIES•1ST DETECTORSAD. LIGO

AD. VIRGO

MiniGRAIL

PACO

EGO

DUAL

3RD GENERATION

FOR IFOS•SILICON MIRRORS•SILICON SUSPENSIONS•HIGHER LASER POWER•BETTER COATINGS•LOW TEMPERATURE

FOR RESONATORS•CRISTALLINE MATERIALS•DOUBLE RESONATORS• T < 10mK•SQL

Z = 1

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 8

… coming back on Earth3 Objectives for STREGA

1 Research on Materials Outcomes

- Selection or Development of the most suitable materials forMirrors, Suspensions and Resonant Masses

- Development of low losses Dielectric Coatings

- Investigation on Acoustic Emission caused by Cosmic Rays

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 9

… coming back on Earth3 Objectives for STREGA

2 Research on Cryogenics Outcomes

- Development of a cryogenic system for the interferometers with a low mechanical noise

- Design of a last stage suspension able to provide 1W of heat flow at ~5K

- Development of a low noise ultra cryogenic system (~10mK) for resonant detectors

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 10

… coming back on Earth3 Objectives for STREGA

3 Research on Thermal Noise Outcomes

- Development of facilities for the direct measurement of Thermo-elastic noise

- Development of facilities for the direct measurement of Photo-elastic noise

- Novel read-out configurations able to reduce the effect of thermal noise on the signal detected with resonant bars

ILIAS-GW Meeting, Orsay, 5th – 6th Nov 2004 11

Some Numbers

124 people of 25 different groups (subgroup of the Network) € 1794 per person per year

STREGA web page: http://www.ego-gw.it/ILIAS-GW/

STREGA has the largest number of deliverables among the ILIAS activities (15 in the first 18 months)

GOOD WORK !!