Multi-Messenger Astronomy

Multi-Messenger AstronomyAY 1710/19/2011

OutlineWhat is Multi-messenger astronomy?PhotonsCosmic RaysNeutrinosGravity-WavesSample-ReturnOutlineWhat is Multi-messenger astronomy?PhotonsCosmic RaysNeutrinosGravity-WavesSample-ReturnWhat is Multi-Messenger Astronomy?Its Astronomy with multiple messengers!One of the first instances of a clear cut meaning in an astronomical definitionInforms you about different conditions in the same objectPhotons come from the surface of the SunBut neutrinos are made from the nuclear reactions in the coreOutlineWhat is Multi-messenger astronomy?PhotonsCosmic RaysNeutrinosGravity-WavesSample-ReturnPhotonsMost widely used messenger particle in AstronomyEasy to detect (unlike neutrinos)Can travel long distances (unlike nuclear messenger particles)However.Not all frequencies are created equalPhotonsAstronomers are merely fleas on the dog of industryCheap SiliconOptical

RadarRadio

Nuclear TestingGamma rays

Bell company got Jansky to investigate 10-20 meter waves and the interference with sending them across the atlantic. He discovered nearby thunderstorms, distant thunderstorms and emission from the galactic center! But then Bell found out it didnt interfere and refused his request for a 100 ft dish to further study the galactic center. He did no more astronomy.

Radar had pushed the ability to receive signals to shorter and shorter wavelengths where antennas of reasonable size could be built to examine smaller regions of the sky (narrow beam widths).

7PhotonsX-Ray AstronomyBegan as a series of Balloon and V-2 Rocket experiments in the 1960sUsually a single astronomical instrument tagging along with various other experiments (atmospheric measurements, NIH experiments, etc.)Initially measured the Sun, and eventually led to the discovery of bright X-ray sources in the Milky Way

PhotonsChandra X-Ray Observatory3-10 keVLaunched in 1999Plane parallel mirrors

PhotonsGalactic and Extragalactic X-Ray Astronomy10 keV / kb ~ 108 K

Photons

PhotonsIntra-Cluster GasCooled by Thermal Bremsstrahlung

Evidence for metal lines in the Intra-cluster gasHow did they get there?

PhotonsX-Ray emission within Galaxies?SupernovaeAccreting Black holesX-ray binariesNS+NSNS+BlackholeNS+WDetc

OutlineWhat is Multi-messenger astronomy?PhotonsCosmic RaysNeutrinosGravity-WavesSample-ReturnCosmic RaysWhat are Cosmic RaysHighly Energetic atomic and subatomic particles~90% Protons, 9% He, 1% other (mostly heavy elements)

Cosmic Rays

Cosmic Rays

Cosmic RaysGalactic Cosmic RaysOriginate in supernova remnantsAccelerated by magnetic fieldsLocalization is hardDeflected by magnetic fields in the galaxyCan fragment as travel

Cosmic RaysExtragalactic Cosmic RaysSome cosmic rays have enough energy to leave the galaxy1 / m^2 / yr hits the EarthLittle is known about their composition (statisitics problem)Some evidence they come from AGNCould also come from colliding galaxies, the early universe, decay of superheavy particlesCosmic Rays

Cosmic Rays and You

OutlineWhat is Multi-messenger astronomy?PhotonsCosmic RaysNeutrinosGravity-WavesSample-ReturnNeutrinos

86 Holes5160 Optical SensorsSensitive to high energy neutrinosNeutrinosSolar ObservationSuper-Kamiokande produced a neutrino image of the Sun

Neutrinos

NeutrinosSupernova Early Warning SystemNeutrinos were detected from SN 1987A before the optical counterpart was discoveredIceCube and other neutrino experiments are poised to detect the neutrinos from the next nearby (galactic) supernovaIcecube will have the ability to pinpoint the neutrino origin accurately

NeutrinosAvoiding Cosmic Ray ConfusionIceCube also has a cosmic ray detector array on the Antarctic surfaceCoincidence between cosmic ray detection and neutrino detection lowers confusion rates

This junk is interesting to some people!Cosmic Rays with IceCube

Cosmic Rays with IceCube

Local Magnetic fields? Stellar magnetic fields? A handful of close pulsars? OutlineWhat is Multi-messenger astronomy?PhotonsCosmic RaysNeutrinosGravity-WavesSample-ReturnGravity Waves

Gravity Waves

Gravity Waves

Gravity Waves

Gravity Waves

Gravitational WavesWhat the gravity wave sky actually looks like:Gravity Waves

Gravity Waves

Advanced LIGOBigger, Better, Stronger20x stronger laserSeismically isolated from 40 Hz down to 10 HzReduced thermal noiseAn actual detection likely!2015*

*Actual finish time may varyOutlineWhat is Multi-messenger astronomy?PhotonsCosmic RaysNeutrinosGravity-WavesSample-ReturnSample Return

Sample Return

Sample ReturnCollect cometary and interstellar dust particles in aerogelReturn the sample to EarthTake millions of photographs of aerogel to identify dust grainsstardust@home45 interstellar dust grains identified!Sample Return

Sample ReturnList of findings:Organic compoundsAmorphous silicatesOlivine and pyroxene (Solar system matter well mixed with ISM)

Sample ReturnSupernova DebrisFe-60 has a half life of 2.6 Myr (all of it that formed with the Earth is gone)

Sample ReturnThis points to a core-collapse supernova within a few 10s of parsecs of the Earth exploding several million years agoContributed to the Local Bubble of the ISMWe are in a low density, high temperature, ~150 light year region of the ISM