Workshop at STScI, 2011 June 28-30 “Intermediate-Luminosity Red Transients” K. Davidson

1. Workshop at STScI, 2011 June 28-30 “Intermediate-Luminosity Red Transients” K. Davidson

2. Diverse aspects of the Physics of Eruptions, especially those propelled by Eddington. or, Excerpts from The Missing Manual. F E Workshop at STScI, 2011 June 28-30 “Intermediate-Luminosity Red Transients” K. Davidson

3. Part the first: Radiation temperature. What does an eruption look like when it is visually most spectacular ? How big and how hot is the UV-to-far-red photosphere ?

12. A LATE-NEOLITHIC CALCULATION … Question: Supposethatastellarwindoreruptiveoutflowis dense enoughtobeopaque. Then,WHAT ISTHE RELATION BETWEENAPPARENTRADIATIVE TEMPERATUREANDMASS-LOSSRATE ? Caveat Tc = APPARENT temperature or CHARACTERISTIC temperature. EFFECTIVEtemperatureisill-defined!

13. Fair approximation: 1. Solve spherical scattering problem with F ~ 1/r2, opacity = scattering + absorption, mostly scattering. 2. Assume T(r) = radiation-density temperature. 3. Temperature of escaping radiation = approximately T(thermalization depth). Of course varying degrees of better approximation can be arranged.

14. ( Another story: The elusive “Modified Eddington Limit” )

16. -- FROMTHE1987PAPER -- LIKETHEPREVIOUSFIGURE, AXESINTERCHANGED

17. Note: No need for spherical symmetry, steady flow, etc. Can be an outburst, a bipolar thing, etc.

18. 7000 K*ISASPECIALTEMPERATURE INTHEH-RDIAGRAM. * (Really meaning 6000—8000 K.)

19. 7000 KISASPECIALTEMPERATURE INTHEH-RDIAGRAM. NATURAL LIMIT FOR MASSIVE OUTFLOWS: -- SNae; LBV’s; Novae; Eta Car; Impostors; … ? --

21. 7000 KISASPECIALTEMPERATURE INTHEH-RDIAGRAM. NATURAL LIMIT FOR MASSIVE OUTFLOWS: -- SNae; LBV’s; Novae; Eta Car; Impostors; … ? -- Analogous to the Hayashi Limit at 3000 K …

22. 7000 KISASPECIALTEMPERATURE INTHEH-RDIAGRAM. NATURAL LIMIT FOR MASSIVE OUTFLOWS: -- SNae; LBV’s; Novae; Eta Car; Impostors; … ? -- Analogous to the Hayashi Limit at 3000 K … Moreover, B.C. Is close to zero at 5500--7500 K; allowing visually bright stars.

23. ( memo ) Shaviv plural & novae, same problem.

24. SUPER – EDDINGTON FLOWS (CONTINUUM DRIVEN WIND)

25. Observed characteristics of Eta Car 1836—1858 event: -- L roughly 2—5 times Eddington for 5—20 years -- Ejected mass 10—20 Msun -- Radiated energy -- Kinetic energy

26. Observed characteristics of Eta Car 1836—1858 event: -- L roughly 2—5 times Eddington for 5—20 years -- Ejected mass 10—20 Msun -- Radiated energy -- Kinetic energy Set up normal equations, try to make it work.

27. Observed characteristics of Eta Car 1836—1858 event: -- L roughly 2—5 times Eddington for 5—20 years -- Ejected mass 10—20 Msun -- Radiated energy -- Kinetic energy Set up normal equations, try to make it work. Doesn’t work; ejects too much mass, too fast .

28. Quoting Shaviv...

29. Quoting Shaviv... Typo above! Read “sonic radius”, not “shock”

30. “POROSITY” (N. Shaviv)

31. Quoting Shaviv...

32. Result: Can simulate Eta Car Great Eruption, Novae. More or less.

33. Tired old joke: Theorist, “assume a spherical cow...”

34. Tired old joke: Theorist, “assume a spherical cow...” 21st century version: Theorist, “assume a homogeneous cow...”

35. Which are the dense places – Bright or dark? RADIATIVE TRANSFER PROBLEM - Granulation with various size scales – Equatorial Skirt

38. SN 2010da: X-rays and He II 4687 ??

39. -- 30 --

40. He II 4687 ETA CAR “EVENT” 2009

43. 2-10 keV X-rays He II 4687

44. Refs. for physics of He II 4687, soft X-rays, • and shock breakup: • J. Martin et al, ApJ 640, 474 (2006) • Soker & Behar, ApJ 652, 1563 (2006) • Mehner et al, new astro-ph