G M LIGO “First Lock” Barry Barish 21 October 2000

G M LIGO Livingston Observatory Hanford Observatory LIGO is operated by MIT & Caltech for the National Science Foundation

G M LIGO Livingston Observatory

G M LIGO Hanford Observatory

G M LIGO beam tube  LIGO beam tube under construction in January 1998  65 ft spiral welded sections  girth welded in portable clean room in the field 1.2 m diameter - 3mm stainless 50 km of weld NO LEAKS !! LARGEST HIGH VACUUM SYSTEM IN THE WORLD ~ 16,000 CUBIC METERS

G M LIGO vacuum equipment

G M Detection of Gravitational Waves precision optical instrument LIGO (4 km) will be able to detect a stretch (squash) of m !! ( a small fraction of the size of a proton) This will enable detection of gravitational waves from a distance as far as 600 Million light years LIGO interferometer

G M Einstein’s Theory of Gravitation Newton’s Theory “instantaneous action at a distance” Einstein’s Theory information carried by gravitational radiation at the speed of light

G M  Helium Burning Main Sequence in massive stars, a series of nuclear burning stages transforms the star into an onion-like shell structure, until Silicon and Sulfur burning create a core of iron (and other iron-peak elements.  Each successive nuclear burning stage releases less energy than the previous stage, so the lifetime in each stage becomes progressively shorter. Evolution of Stars For a 20 M  star: Main sequence lifetime ~ 10 million years Helium burning (3-) ~ 1 million years Carbon burning ~ 300 years Oxygen burning ~ 2/3 year Silicon burning ~ 2 days nuclear burning vs gravity

G M explosion of a star supernova sequence gravitational waves ’s light

G M SN 1987A Large Magellanic Cloud (LMC) First SN with observations of star that exploded - Sk Supergiant with T = 16000K Luminosity = 100,000L  Mass ~ 20M 

G M Supernovae Observations HISTORICAL SUPERNOVAE (OUR GALAXY) & SN Centaurus in the southern sky & SN The Crab Supernova in Taurus recorded by Chinese and Native American astronomers & SN Tycho’s Supernova, studied in detail by Tycho Brahe & SN Kepler’s Supernava +other possible Milky Way supernovae our galaxy 1/50 years & within Virgo Cluster ~ 1 year Kepler Super Nova Remnant Cygnus Loop Remnant

G M Supernova Remnants pulsars PSR is among the strongest known pulsars (radio signal – Arecibo)

G M Supernovae time evolution Birth and Death of Stars

G M Supernovae gravitational waves Non axisymmetric collapse ‘burst’ signal Rate 1/50 yr - our galaxy 3/yr - Virgo cluster

G M LIGO Plans major milestones 1994 Funding Approved by NSF 1996 Began Construction 1999Construction Complete (vacuum achieved in LIGO) 2000“First Lock” (complete operating LIGO interferometer) 2001First Coincidence (both LIGO sites) 2002+Initiate Search for Gravitational Waves (Science !)