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1.2 Management Activity N1 – Table 1a: Contribution of the involved contractors. # Name Short name 1 Commissariat à l’Energie Atomique, Paris, France 2 Centre National de la Recherche Scientifique, Paris, France CNRS 3 Istituto Nazionale di Fisica Nucleare, Frascati, Italy INFN Annual Report CEA Short description of specific roles in the consortium N1: N2: N3: TA1: JRA1 N1: N2 N3 N4: N5: N6: TA1 JR1 JR2: JR3: Optical mesurments on crystalline materials at room as at low temperature. Production of dielectric coatings. Set up of high finesse cavity at low temperature. N1: N2: N3: N4: N5: N6: TA1: JR1: JR2 JR3: Coordination of the activity. Q measurements on thin silicon fibres and on membranes with and without dielectric coatings applied, Mo and SiC cantilever blades, at room as at low temperature. Set up of seamless copper RF superconducting cavities. Measurements of the acoustic effect generated by particle absorption on metals across the superconducting transition. Design of the low temperature seismic suspension system and of the lower stage elements. Modification of cryogenic 1 Contract [RII3-CT-2004-506222]t # Name Short name Short description of specific roles in the consortium facilities and construction of dedicated sensors. Construction and testing of resonators. Construction of optical readout systems and design of large area detector readouts. N3: N4: 9 Max-Planck Society for the advancement of Science, represented by Max-Planck-Institute for Nuclear Physics, Heidelberg, Germany N5: MPIK N6: JRA1 JRA2: JRA3: Coordination of the activity N5: Istituto di Fotonica e 13 Nanotecnologie-CNRSezione di Trento, Italy IFN European Gravitational 14 Observatory, Cascina, Italy EGO JRA3: Realisation of a vacuum chamber with a micropositioning system for studying the effect of the conditioning, thermal, and machining procedure of the electrodes on the breakdown field. N1: N5: N4: Leiden University – 15 LION Institute of Physics, Netherlands MiniGRAIL University of Glasgow, 19 United Kingdom U.Glasgow N5: JRA2: JRA3: Vacuum-annealing of the 1.4 ton sphere; Develpment of two-stage SQUIDS; Construction of CuAl resonators and testing on spherical resonator (tasks M2 and C2) N1: Membership of EB N5: Participation to WG2 and WG3 JRA3: Coordination of the activity. Upgrade of cryogenic set-up for Q measurements of large silicon cylinders (M1); set-up of the measuring cavity of the 10m interferometer for the direct thermal noise measurement (T1); upgrade of the Q measurement facility at room temperature for the Annual Report 2 Contract [RII3-CT-2004-506222] # Name Short name Short description of specific roles in the consortium investigation on coatings (M4) N1 – Table 2a: Contribution of the involved institutions, not signatories to the Contract. Institution Friedrich-Schiller University, Germany contribution JRA3: Q measurements at low temperature, tasks M1, M4 and M5 Annual Report 3 Contract [RII3-CT-2004-506222] 1.5.3 JRA3: Study on Thermal Noise Reduction in Gravitational Wave Detectors Coordinator: G. Cagnoli (University of Glasgow) Deputy Coordinator: K. Danzmann (MPI/Hannover) The scientific activities in JRA3 (STREGA) aim to the developments of materials, methods and technologies that will reduce the thermal noise level in gravitational wave detectors of 3rd generation by a considerable amount (10 times with respect to the noise level of 2nd generation detectors). The most promising technological solutions that will allow such improvement in the detectors performance are: cryogenic operation for interferometers; quantum limited readout systems and new materials for acoustic detectors. The implications of these new development lines are several; consequently this JRA has been organized in three main objectives: M) Materials for Advanced Detectors; C) Cryogenics for Advanced Detectors; T) Thermal noise specific studies. All the three objectives are relevant for all the different types of detectors. In more details, a list of items related to each objective follows. Materials for Advanced Detectors. Silicon seems so far the most promising material for cryogenic interferometer; suitable silicon suspensions and low loss coatings have to be developed. For acoustic detectors new materials are CuAl, SiC and Mo for main test masses and transducers; high coupling and low loss capacitor for capacitive readouts; coatings for optical readouts. Superconducting radio-frequency cavities and an investigation on acoustic effect generated by cosmic rays complete the objective. Cryogenics for Advanced Detectors. The feasibility study of low noise cryogenic suspensions with sufficient high level of heat extraction is fundamental for future interferometers. At the same time quantum limited acoustic detectors need to operate at ultra low temperature (tens of mK) and an investigation on this front, concerning the MiniGRAIL detector, complete the objective. Thermal noise specific studies. The development of facilities for direct measurement of thermal noise is one of the tasks of this objective. Another phenomenon under investigation is the photo-thermal effect. Finally, a study of thermal noise reduction in future resonant detectors using large area readout systems is conducted. JRA3 – Table 1a: Participating institutes. Participant number Participant short name Person-months 2 3 13 15 19 CNRS INFN IFN MiniGRAIL U.Glasgow 22 184 (24) 8 12 22 Total 248(24) JRA3 – Table 1b: Other entities foreseen to contribute to the project (but are not signatories to the Contract). Name of Istitution City Country Friedrich-Schiller University Jena Germany Annual Report 4 Contract [RII3-CT-2004-506222]t Deliverable/ Milestone No m1 m2 d1 Deliverable/Milestone Name JR3– Table 2: Deliverables. Workpackage /Task No - Large cryostat in Glasgow operative, first Q measurement - Cryogenic low-absorption measurements facility in Paris operative d3 d4 - Report on the transducers test m5 - First seamless copper cavity - Measurement of the critical temperature of the Niobium sputtered samples - Construction Drawings for a prototype cavity - Application of first coatings to silicon substrates - Report on results of the investigation of losses of substrates - Production of a silicon fibre with constant crystalline axis orientation - Local cooling by Total Internal Reflection on a BaY2F8 crystal doped with Yb3+ - Report on room temperature measurements of thermal and mechanical properties of fibres produced by the collaboration - Report on the effect estimation of local cooling of a fibre on its level of thermal noise - Installation of the dilution refrigerator in the Frascati facility - Acoustic emission detector for Nb bar ready for taking measurements - Report on low T measurements on Al using an electron particle beam - Installation of the Sumitomo PTR - First cooling of the VFC - Drawings of the first payload prototype - Report on VFC thermal behaviour - Cool down MiniGRAIL to below 50 mK with more than 3 transducers - Measure the noise temperature of the sphere at T<50 mK and acquire data in coincidence with other antennas - Further improvement of 2-stage DC-DROS SQUIDs and noise optimization - Report on noise measurements below 50 mK with 3 transducers - Report on nearly quantum-limited SQUIDs - Production of high-compliance very high m3 m4 m6 d5 m7 d6 m8 m9 d7 d8 m10 M11 D9 M12 M13 D10 D11 M14 M15 M16 D12 D13 M17 WP1 / M2 WP1 / M3 WP1 / M4 Planned Achieved 24 271 18 18 24 24 24 24 INFN (3) 24 24 Leiden (15) 22 22 INFN (3) INFN (3) Leiden (15) INFN (3) 24 24 24 24 24 18 INFN (3) 30 212 INFN (3) 24 24 Glasgow (19) 30 24 Glasgow (19) INFN (3) 24 24 INFN (3) 24 303 INFN (3) 24 24 INFN (3) 24 24 INFN (3) 24 24 INFN (3) 18 244 INFN (3) 18 155 INFN (3) 24 24 INFN (3) INFN (3) INFN (3) INFN (3) 15 15 18 24 15 15 18 24 Leiden (15) 24 306 Leiden (15) 24 30 Leiden (15) 24 24 Leiden (15) 24 24 Leiden (15) INFN (3) 24 24 24 24 CNRS(2) WP1 / M1 - Silicate bonding samples ready for testing - Report on the investigation plan of the effect of doping in Si - Measurement of field emission current in small capacitors - Test of resonant capacitive transducers on a resonant sphere - Report on Q measurement at low T d2 Lead Contractor(s), other participants CNRS (2) Glasgow (19) CNRS (2) Glasgow (19) CNRS (2) Glasgow (19) WP1 / M5 WP1 / M6 WP2 / C1 WP2 / C2 WP2 / C3 Annual Report 5 Contract [RII3-CT-2004-506222] M18 D14 M19 M20 D15 thermal conductivity suspensions - Production and assembly of the cryo-facility cryostat - Drawings of all the elements of the suspension chain - Installation of the silica suspension - Locking of the laser on the stabilization cavity in the Perugia facility - Frequency stabilization of the master and slave lasers in the IGR interferometer optimized - Measurement of photoelastic noise with short cavities (small waist) - Installation of a high-finesse cavity in a cryostat INFN (3) 30 30 INFN (3) 24 24 Glasgow (19) 24 307 Glasgow (19) 24 24 Glasgow (19) 24 24 24 24 24 24 24 24 24 24 27 308 24 24 24 24 WP3 / T1 CNRS (2) INFN (3) CNRS (2) M22 WP3 / T2 INFN (3) CNRS (2) D16 - Technical report INFN (3) IFN (13) M23 - Construction of a Folded Fabry-Perot cavity INFN (3) - Construction and optical test of a concaveIFN (13) M24 convex cavity INFN (3) - Development of a mechanical amplifier with WP3 / T3 IFN (13) M25 negligible thermal noise INFN (3) IFN (13) D17 - Conceptual design of a DUAL detector INFN (3) CNRS (2) Numbers on the delayed milestones are explained and referred to specific points in the section Major achievements in the second 12 months M21 Annual Report 6 Contract [RII3-CT-2004-506222] JR3– Table 3: Meetings in the reporting period. Date 28/04/2005 Title/subject of meeting /workshop C1-C3 Meeting Location Cascina Number of attendees 5 Website address http://www.egogw.it/ILIASGW/STREGAmeetings .html http://www.egogw.it/ILIAS-GW/ 24-25/10/05 ILIAS – GW General Meeting Palma de Mallorca, Spain 56 17/02/2006 Silicon collaboration start up meeting Phone conference 10 http://www.aei.mpg.de/ ~sintes/ILIAS/ Annual Report 7 Contract [RII3-CT-2004-506222] JR3– Table 4 : Role of participant contractors Deliverable No d1 d2 d3 Deliverable Name Workpackage /Task No Contractors - Silicate bonding samples ready for testing - Report on the investigation plan of the effect of doping in Si WP1/M1 CNRS (2) INFN (3) Glasgow (19) - Report on Q measurements at low T d4 - Report on the transducers test d5 - Construction Drawings for a prototype cavity d6 - Report on results of the investigation of losses of substrates d7 - Report on room temperature measurements of thermal and mechanical properties of fibres produced by the collaboration WP1/M2 INFN (3) Leiden (15) WP1/M3 INFN (3) WP1/M4 - Report on the effect estimation of local cooling of a fibre on its level of thermal noise d9 - Report on low T measurements on Al using an electron particle beam Annual Report (2): Task coordination (19): Fabrication of silicate bonds (2): Task coordination (19): Purchase of samples. Fabrication of mechanical parts. Writing of the report (3): Task coordinator Purchase of samples Running of the cryostat Writing of the report (3): Task coordination (15): Fabrication of samples Running of the cryostat (3): Task coordination Construction of the detector prototype (19): Task coordination Writing of the report Purchasing and fabrication of samples (2): Deposition of coatings (3): Task coordination Production of samples Writing of the report WP1/M5 d8 Glasgow (19) INFN (3) CNRS (2) Role in the deliverable WP1/M6 8 INFN (3) Glasgow (19) INFN (3) (3): Task coordination Production of samples Writing of the report (3): Task coordination Running of the cryostat Running of the accelerator Writing of the report Contract [RII3-CT-2004-506222]t Role in the task (in addition to the column at left) (3): Partecipation to the STREGA and ILIAS General Meetings (19): Partecipation to the STREGA and ILIAS General Meetings (3): Partecipation to the STREGA and ILIAS General Meetings (15): Partecipation to the STREGA and ILIAS General Meetings (3): Partecipation to the STREGA and ILIAS General Meetings (3): Mechanical and electronic upgrade of the cryostat Partecipation to the STREGA and ILIAS General Meetings (19): Partecipation to the STREGA and ILIAS General Meetings (19): Mechanical and electronic upgrade of the cryostat Partecipation to the STREGA and ILIAS General Meetings (3): Mechanical, electronic and optical parts for thermal conduction and expansion measurements Partecipation to the STREGA and ILIAS General Meetings (3): Partecipation to the STREGA and ILIAS General Meetings d10 - Drawings of the first payload prototype WP2/C1 d11 - Report on VFC thermal behaviour d12 - Report on noise measurements below 50 mK with 3 transducers WP2/C2 d13 - Report on nearly quantum-limited SQUIDs d14 - Drawings of all the elements of the suspension chain d15 - Frequency stabilization of the master and slave lasers in the IGR interferometer optimized INFN (3) Leiden (15) (3): Task coordination Drawing of the First Payload Production of mechanical parts Small scale prototype produced (3): Task coordination Set up of the whole feed-back system Writing of the report (15): Task coordination Running of the cryostat Production of the 3 transducers Writing of the report (15): Task coordination Running of the cryostat Production of the SQUIDs Writing of the report WP2/C3 INFN (3) (3): Task coordination Production of the Drawings Writing of the report WP3/T1 Glasgow (19) INFN (3) (19): Task coordination Purchasing and production of electronic components Writing of the report d16 - Technical report WP3/T2 CNRS (2) INFN (3) d17 - Conceptual design of a DUAL detector WP3/T3 IFN (13) INFN (3) CNRS (2) (2): Task coordination Purcahsing of electronic, mechanical and optical components Writing of the report (3): Purcahsing of electronic, mechanical and optical components Post doc salary Writing of the report (13): Task coordination Simulation Writing of the report Annual Report 9 Contract [RII3-CT-2004-506222] (3): Partecipation to the STREGA and ILIAS General Meetings (15): Partecipation to the STREGA and ILIAS General Meetings (3): Mecanical parts for the upgrade of the large cryostat. Partecipation to the STREGA and ILIAS General Meetings (19): Production of silica fibres Partecipation to the STREGA General Meetings (3): Mechanical, electronic and optical parts interferometer upgrades Partecipation to the STREGA and ILIAS General Meetings (3): Partecipation to the STREGA and ILIAS General Meetings (3): Components for the folded Fabry-Perot cavity and Post doc salary (2): Simulation (3): Simulation Writing of the report Annual Report 10 Contract [RII3-CT-2004-506222] Partecipation to the STREGA and ILIAS General Meetings (13): Partecipation to the STREGA and ILIAS General Meetings Major achievements in the second 12 months A short presentation of the most relevant events and facts occurred in the reporting period is shown here. Materials for Advanced Detectors A new group from Jena has joint the STREGA collaboration in October 2005. Their expertise is on cryogenic Q measurements. Silicon is the most promising material for cryogenic interferometers and several groups have been equipped with cryogenic setups for optical and mechanical measurements of this material. 1At this moment none of the experimental setups devoted to the Q measurements are free of systematic errors, introduced by the suspension or clamping systems used for the samples. The challenge taken by these laboratories is high because only few examples of these measurements can be found in literature and the difficulty on reproducing the data is holding back some of the expected development of the scientific activities in STREGA. In order to use at best the facilities in the different laboratories a Silicon Collaboration Group has been formed at the second yearly meeting of STREGA. The 7 participating groups (Florence, Glasgow, Jena, Legnaro, Perugia, Pisa, Roma1) agreed on planning a coordinate scientific activity around the following research topics: i) crystal orientation effect; ii) doping effect; iii) surface effect; iv) coating and diffraction gratings; v) bonding techniques; vi) full scale prototype (presentation of G.Cagnoli at http://www.ego-gw.it/ILIAS-GW/ILIAS-GWMallorca_Agenda_v2.html). Optical losses in silicon crystals are so low to be very close to the detection limit imposed by the shot noise of photons. An upgrade of the facility is being made. Samples of dielectric coatings on silicon substrates and silica-bonded silicon pieces have been produced. 3The facility for the production of silicon fibres has to be optimized because the produced samples have not yet the crystal orientation constant. The preparation of the seed seems to be the solution. The activity had an unexpected problem: it has been found that the samples produced so far were contaminated by the crucible. The activity is continuing. It has been demonstrated the inverse fluorescence in the crystal suitable to be used in the suspensions but the cooling rate is too low to be used in future detectors. First Q measurements at low temperature of SiC cantilever blades. The Q is quite low presumably because of the sintered nature of the sample. More compact structure samples are now being tested. The electron beam welding did not produce good results on mechanical losses as expected. Q measurements on a hollow sphere showed that a thin layer of brazing material produces very encouraging results. The effort of developing an optical readout for acoustic detectors was divided so far on the development of two setups: one dedicated to the AURIGA detector (a future upgrade) and the other developed for DUAL (folded Fabry-Perot and Convex-Concave cavity). Since the AURIGA detector will be operative for several years in the present status, the STREGA collaboration has decided to spend all the efforts for the R&D of DUAL. 2The superconducting radio-frequency, niobium-sputtered, seamless copper cavities have been successfully produced and tested and due to an unexpected fast delivering by the companies involved in the production of parts, the activities of this year have been completed in advance. Annual Report 11 Contract [RII3-CT-2004-506222] 4The detection of particles-induced acoustic-emission in a superconducting aluminium bar has been delayed due to the unexpected long leading time of the dilution refrigerator. 5The facility in Frascati was used to complete earlier than expected the investigation on Niobium. Cryogenics for Advanced Detectors The Vibration Free Cryocooler has been successfully realized and tested and this represents a significant achievement for a future cryogenic interferometer: this first prototype achieves already a very good level of vibration extinction. A small prototype (scale 1:3.5) of last stage suspension made of silicon has been designed and all its components constructed. The large cryostat at EGO has been mounted and positively tested. The designing of the cryogenic superattenuator has already started. After the designing of the first suspension elements done this year, it has been understood that the production of a full cryogenic superattenuator is not necessary because the single elements of the suspension chain can be tested in the large cryogenic facility already mounted at EGO. The final deliverable at the end of the project is going to be a Design of the full cryogenic superattenuator rather than the production of it. 6The MiniGRAIL spherical resonant detector has achieved a temperature of 60 mK. Although a not yet identified problem on the dilution refrigerator did not allow reaching the temperature of 50 mK, several successful tests on the transducer chain have been done. Thermal noise specific studies 7The upgrade of the Glasgow interferometer is going on with a slight delay due to unexpected fault of the laser that had to be replaced. The laser replacement had a consequence on the optics also since the matching of the new laser beam to the old cavity had to be done again. A smaller spot size has been obtained in the photo-thermal effect facility in Florence whereas the low-temperature high-finesse cavity assembled in Paris has shown the first resonances. The theoretical study of the performance of the DUAL detector has been concluded and presented here. 8The convex-concave cavity activity is being extended for few moths further in the third year. The same group has devoted more effort than expected in the successful construction of the first folded Fabry-Perot cavity. Glossary 1st Generation Detectors. Current generation of detectors: aluminium bars for resonators and interferometers at room temperatures with metal suspensions. nd 2 Generation Detectors. Known as Advanced Detectors: mK operational temperature for resonator, quantum limited; room temperature interferometers with monolithic silica suspensions, high power lasers and signal recycling. 3rd Generation Detectors. These are the cryogenic underground interferometers using squeezed light. Fabry-Perot cavity. Optical cavity made of a full reflecting mirror and a partially transmitting/reflecting one, facing each other. From the latter the light is injected and if the length of the cavity is an integer number of half wavelengths and the curvature of the mirrors is appropriate, the light can resonate in a TEoo Gaussian mode. Last stage. It is the lower stage of the suspension in an interferometer. It consists of the mirror, its suspension fibres and the upper stage. Annual Report 12 Contract [RII3-CT-2004-506222] Locking. It is an active control of the frequency of the laser or the position of the mirror/s of an interferometer in order to achieve a desired condition. In most of the cases presented in this report, this condition corresponds to the resonant of the cavities. Marionetta. It is the stage immediately above the mirror in an interferometric Gravitational Wave Detector. It has electromechanical actuators for the steering of the mirror. Monolithic suspension. They are achieved when the suspension fibres are of the same material of the mirror and of the marionette. Q measurements. For Q is meant Quality Factor of the resonance. The sample is excited in one of its modes (generally mechanical modes) and the decay of free oscillation is recorded. The Q is worked out from the characteristic decay time . The Q quantify the losses. Superattenuator. It is the chain of passive mechanical filters (harmonic oscillators) whose aim is to suspend the mirror and isolate it from the seismic motion that is 10 orders of magnitude larger than the expected effect of gravitational waves. Test mass. It is the mass sensing the gravitational wave. For resonator is the main mass; for RF detectors is the superconducting cavity; for interferometers is each mirror of the FabryPerot cavities. Annual Report 13 Contract [RII3-CT-2004-506222] 2. List of deliverables Activity Deliverable (NAx; JRAy) No 1 2 3 4 5 6 7 8 JRA3 9 10 11 12 13 14 15 Deliverable Name Silicate bonding samples ready for testing Report on the investigation of the effect of doping in Si Report on Q measurement at low T Report on the transducers test Construction Drawing for a prototype cavity Technical report Report on room temperature measurement of thermal and mechanical properties of fibres produced by the collaboration Report on the effect estimation of local cooling of a fibre on its level of thermal noise Report on low temperature measurement on Al using an electron particle beam Drawings of of the first cryo payload prototype Report on VFC thermal behaviour Report on noise measurements below 50 mK with 3 transducers Report on nearly quantum-limited SQUIDs Drawings of all the elements of the suspension chain Report on the new frequency stabilization system for the IGR interferometer Workpackage /Task No Delivered by Contractor(s) Planned (in months) Achieved (in months) CNRS (2) Glasgow (19) 24 24 CNRS (2) Glasgow (19) 24 24 INFN (3) 24 24 INFN (3) 24 24 WP1 / M3 INFN (3) 24 24 WP1 / M4 Glasgow (19) INFN (3) 24 24 INFN (3) 24 24 INFN (3) 24 24 INFN (3) 24 24 INFN (3) 18 18 INFN (3) 24 24 Leiden (15) 24 24 Leiden (15) 24 24 WP2 / C3 INFN (3) 24 24 WP3 / T1 Glasgow (19) 24 24 24 24 24 24 WP1 / M1 WP1 / M2 WP1 / M5 WP1 / M6 WP2 / C1 WP2 / C2 16 Technical report WP3 / T2 17 Conceptual design of a DUAL detector WP3 / T3 CNRS (2) INFN (3) IFN (13) INFN (3) CNRS (2) Annual Report 14 Contract [RII3-CT-2004-506222] Annexes Annex 5 – List of Publications Gravitational Waves STREGA M. Bassan et al., First results of the RAP experiment (acoustic detection of particles) in the low temperature regime. J. Phys.: Conf. Ser. 32, (8), 393-7 (2006) G. Cagnoli, R&D on thermal noise in Europe: the STREGA Project. J. Phys.: Conf. Ser. 32, (8), 294-300 (2006) M. Alshourbagy et al., Measurements of thermoelastic properties of crystalline Si fibres. Class. Quantum Grav. 23, (8), S277-85 (2006) F. Marino, M. De Rosa, and F. Marin, Canard orbits in Fabry-Perot cavities induced by radiation pressure and photothermal effects Physical Review E 73, 026217 (2006) M. De Rosa, F. Marin, F. Marino, O. Arcizet, A. Heidmann, M. Pinard, Experimental investigation of dynamic photo-thermal effect Class. Quantum Grav. 23, (8), S259-66 (2006) S. Reid, G. Cagnoli, D. R. M. Crooks, J. Hough, P. Murray, S. Rowan, M. M. Fejer, R. Route and S. Zappe, Mechanical Dissipation in Silicon Flexures. Physics Letters A 351 (2006) 205-21 Gravitational Waves GWA A.Stavirids, K.D. Kokkotas, Evolution equations for slowly relativistic stars Int.J.Modern.Physics D 14, 543-571 (2005). E. Berti and K.D.Kokkotas, Quasinormal modes of the Kerr-Newman black hole: Coupling of electromagnetic and gravitational perturbations. Physical Review D 71, 124008 (2005) H.Sotani and K.D.Kokkotas, Stellar Oscillations in Scalar-Tensor Theory of Gravity. Physical Review D 71, 124038 (2005). K.D.Kokkotas, N.Stergioulas, Annual Report 15 Contract [RII3-CT-2004-506222] Gravitational Waves from Compact Sources Proceedings of 5th International Workshop “New Worlds in Astroparticle Physics”, World Scientific (2005) B.Zink, N.Stergioulas, I.Hawke, C.D.Ott, E.Schnetter, E.Müller, Black hole formation through fragmantation of toroidal poltropes gr-qc/0501080. L.Baiotti, I.Hawke, P.J.Montero, F.Loffer, L.Rezzolla, N.Stergioulas, J.A.Font, E.Seidel Three-dimensional relativistic simulations of rotating neutro nstar collapse to a Kerr Black hole Phys.Rev.D 71, 024035 (2005). I.Hawke, F.Loffler, A.Nerozzi, Excision methods for high resolution schock capturing schemes applied to general relativistic hydridynamics Phys.Rev.D 71, 104006 (2005). B.Giacomazzo, L.Rezzolla, The exact solution of the Riemann problem in relativistic MHD gr-qc/0507102. J.D.Schnittman, L.Rezzolla, Quasi-periodic oscillations in the x-ray light curves from relativistic tori astro-ph/0506702. A.Buonanno, G.Sigl, G.G.Raffelt, H.-Th.Janka, E.Müller, Stochastic gravitational-wave background from cosmological supernovae Phys. Rev. D 72, 084001 (2005). Conferences Annual Report 16 Contract [RII3-CT-2004-506222]