Project Grant 2207475

ENABLING RESEARCH FOR THE THIRD GENERATION GRAVITATIONAL WAVE DETECTORS -THIS AWARD SUPPORTS RESEARCH IN RELATIVITY AND RELATIVISTIC ASTROPHYSICS, AND IT ADDRESSES THE PRIORITY AREAS OF NSF'S WINDOWS ON THE UNIVERSE BIG IDEA. ADVANCED LIGO TRANSFORMED GRAVITATION, ASTROPHYSICS AND COSMOLOGY BY OPENING THE GRAVITATIONAL- WAVE WINDOW ON THE UNIVERSE, ESTABLISHING A NEW PARADIGM FOR MULTI-MESSENGER OBSERVATIONS. THE SCIENTIFIC CASE FOR CONSTRUCTING A NETWORK OF 3RD GENERATION GROUND BASED INTERFEROMETRIC GRAVITATIONAL WAVE DETECTORS WITH ABOUT A FACTOR 10X SENSITIVITY IMPROVEMENT IS COMPELLING. THE DETECTORS WOULD OBSERVE ALL THE COMPACT BINARY COALESCENCES IN THE UNIVERSE AND BRING THE NEW FIELD INTO COSMOLOGICAL RESEARCH. THE MOST REALISTIC WAY TO IMPROVE THE DETECTORS IS BY INCREASING THE LENGTH OF THE INTERFEROMETER ARMS AS THE GRAVITATIONAL WAVE SIGNALS GROW WITH THE LENGTH WHILE MOST OF THE SIGNIFICANT LIMITING NOISE IS INDEPENDENT OF, OR VARIES SLOWLY, WITH THE LENGTH. A SIGNIFICANT FRACTION OF COST OF THE DETECTORS WILL BE IN THE ULTRA-HIGH VACUUM (UHV) SYSTEM NEEDED FOR THE BEAM TUBES AND THE CIVIL WORK IN PREPARING THE SITE. THE TEAM PROPOSES TO EXPLORE A RANGE OF CONCEPTS IN VACUUM TECHNOLOGY THAT COULD REDUCE THE COST OF UHV TUBE SYSTEMS BY A FACTOR OF ABOUT 2X, AMOUNTING TO A SAVING OF $200M TO $300M IN A 3RD GENERATION DETECTOR. THE PROGRAM WILL EXPLORE NOVEL TECHNIQUES TO ECONOMICALLY FABRICATE VACUUM SYSTEMS USING AND BUILDING ON THE LATEST METALLURGICAL AND MATERIALS SCIENCE INNOVATIONS. THE INVESTIGATIONS WILL BE CONDUCTED IN COLLABORATION WITH THE DOE (FNAL) AND AN INTERNATIONAL PARTNER (CERN). THE GROUP WILL ALSO BE SHARING RESULTS WITH THE EU ET VACUUM GROUP IN ITALY (SUPPORTED BY INFN). SUCCESSFULLY IDENTIFYING NOVEL FABRICATION APPROACHES AND BEAM TUBE DESIGNS WILL HAVE APPLICABILITY BEYOND THE IMMEDIATE INTERESTS OF GRAVITATIONAL WAVE ASTROPHYSICS. NEXT GENERATION HIGH ENERGY COLLIDERS THAT DWARF THE LHC WILL ALSO NEED INNOVATIVE CONCEPTS FOR THEIR VACUUM INFRASTRUCTURE. THE APPLICABILITY OF THE MATERIAL COATINGS RESEARCH THAT WILL BE EXPLORED ALSO PROMISES TO HAVE AN ECONOMIC IMPACT IN THE USE OF COATED STEELS FOR VARIOUS INDUSTRIAL APPLICATIONS. THE INITIATIVE HERE, TO ENABLE THE CONSTRUCTION OF 3RD GENERATION DETECTORS, WILL GENERATE NEW OPPORTUNITIES TO ATTRACT, INSPIRE AND EDUCATE FUTURE SCIENTISTS, CITIZENS AND LEADERS. THIS AWARD REFLECTS NSF'S STATUTORY MISSION AND HAS BEEN DEEMED WORTHY OF SUPPORT THROUGH EVALUATION USING THE FOUNDATION'S INTELLECTUAL MERIT AND BROADER IMPACTS REVIEW CRITERIA.