Multi-Messenger Astronomy

1. Multi-Messenger Astronomy AY 17 10/19/2011

2. Outline • What is Multi-messenger astronomy? • Photons • Cosmic Rays • Neutrinos • Gravity-Waves • Sample-Return

3. Outline • What is Multi-messenger astronomy? • Photons • Cosmic Rays • Neutrinos • Gravity-Waves • Sample-Return

4. What is Multi-Messenger Astronomy? • It’s Astronomy with multiple messengers! • One of the first instances of a clear cut meaning in an astronomical definition • Informs you about different conditions in the same object • Photons come from the surface of the Sun • But neutrinos are made from the nuclear reactions in the core

5. Outline • What is Multi-messenger astronomy? • Photons • Cosmic Rays • Neutrinos • Gravity-Waves • Sample-Return

6. Photons • Most widely used messenger particle in Astronomy • Easy to detect (unlike neutrinos) • Can travel long distances (unlike nuclear messenger particles) • However…. • Not all frequencies are created equal

7. Photons • Astronomers are merely fleas on the dog of industry • Cheap Silicon • Optical • Radar • Radio • Nuclear Testing • Gamma rays

8. Photons • X-Ray Astronomy • Began as a series of Balloon and V-2 Rocket experiments in the 1960s • Usually 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

9. Photons • Chandra X-Ray Observatory • 3-10 keV • Launched in 1999 • Plane parallel mirrors

10. Photons • Galactic and Extragalactic X-Ray Astronomy • 10 keV / kb ~ 108 K

11. Photons

12. Photons • Intra-Cluster Gas • Cooled by Thermal Bremsstrahlung • Evidence for metal lines in the Intra-cluster gas • How did they get there?

13. Photons • X-Ray emission within Galaxies? • Supernovae • Accreting Black holes • X-ray binaries • NS+NS • NS+Blackhole • NS+WD • etc

14. Outline • What is Multi-messenger astronomy? • Photons • Cosmic Rays • Neutrinos • Gravity-Waves • Sample-Return

15. Cosmic Rays • What are Cosmic Rays • Highly Energetic atomic and subatomic particles • ~90% Protons, 9% He, 1% other (mostly heavy elements)

16. Cosmic Rays

17. Cosmic Rays

18. Cosmic Rays • Galactic Cosmic Rays • Originate in supernova remnants • Accelerated by magnetic fields • Localization is hard • Deflected by magnetic fields in the galaxy • Can fragment as travel

19. Cosmic Rays • Extragalactic Cosmic Rays • Some cosmic rays have enough energy to leave the galaxy • 1 / m^2 / yr hits the Earth • Little is known about their composition (statisitics problem) • Some evidence they come from AGN • Could also come from colliding galaxies, the early universe, decay of superheavy particles

20. Cosmic Rays

21. Cosmic Rays and You

22. Outline • What is Multi-messenger astronomy? • Photons • Cosmic Rays • Neutrinos • Gravity-Waves • Sample-Return

23. Neutrinos 86 Holes 5160 Optical Sensors Sensitive to high energy neutrinos

24. Neutrinos • Solar Observation • Super-Kamiokande produced a neutrino image of the Sun

25. Neutrinos

26. Neutrinos • Supernova Early Warning System • Neutrinos were detected from SN 1987A before the optical counterpart was discovered • IceCubeand other neutrino experiments are poised to detect the neutrinos from the next nearby (galactic) supernova • Icecube will have the ability to pinpoint the neutrino origin accurately

27. Neutrinos • Avoiding Cosmic Ray Confusion • IceCube also has a cosmic ray detector array on the Antarctic surface • Coincidence between cosmic ray detection and “neutrino” detection lowers confusion rates • This “junk” is interesting to some people!

28. Cosmic Rays with IceCube

29. Cosmic Rays with IceCube Local Magnetic fields? Stellar magnetic fields? A handful of close pulsars?

30. Outline • What is Multi-messenger astronomy? • Photons • Cosmic Rays • Neutrinos • Gravity-Waves • Sample-Return

31. Gravity Waves

32. Gravity Waves

33. Gravity Waves

34. Gravity Waves

35. Gravity Waves

36. Gravitational Waves • What the gravity wave sky actually looks like:

37. Gravity Waves

38. Gravity Waves

39. Advanced LIGO • Bigger, Better, Stronger • 20x stronger laser • Seismically isolated from 40 Hz down to 10 Hz • Reduced thermal noise • An actual detection likely! • 2015* *Actual finish time may vary

40. Outline • What is Multi-messenger astronomy? • Photons • Cosmic Rays • Neutrinos • Gravity-Waves • Sample-Return

41. Sample Return

42. Sample Return

43. Sample Return • Collect cometary and interstellar dust particles in aerogel • Return the sample to Earth • Take millions of photographs of aerogel to identify dust grains • stardust@home • 45 interstellar dust grains identified!

44. Sample Return

45. Sample Return • List of findings: • Organic compounds • Amorphous silicates • Olivine and pyroxene (Solar system matter well mixed with ISM)

46. Sample Return • Supernova Debris • Fe-60 has a half life of 2.6 Myr (all of it that formed with the Earth is gone)

47. Sample Return • This points to a core-collapse supernova within a few 10s of parsecs of the Earth exploding several million years ago • Contributed to the “Local Bubble” of the ISM • We are in a low density, high temperature, ~150 light year region of the ISM