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Gas and Dust Around Massive SN Progenitors at the Extremes

NGC 7654 and BD + 60  2522 O6.5 (n) fp NASA , ESA, Hubble Heritage Team ( STScI /AURA), F . Summers, G. Bacon, Z. Levay , and L. Frattare.  Carinae VLT/VISIR 12.8  m Mehner + 2019. NGC6888 and WR136 Spitzer/MIPS 24  m, H , XMM/Newton Toala + 2015.

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Gas and Dust Around Massive SN Progenitors at the Extremes

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  1. NGC 7654 and BD +60 2522 O6.5 (n)fp NASA, ESA, Hubble Heritage Team (STScI/AURA), F. Summers, G. Bacon, Z. Levay, and L. Frattare  Carinae VLT/VISIR 12.8 m Mehner+ 2019 NGC6888 and WR136 Spitzer/MIPS 24 m, H, XMM/Newton Toala+ 2015 Gas and Dust Around Massive SN Progenitors at the Extremes Pat Morris, IPAC/Caltech Exploring the Infrared Universe: The Promise of SPICA Aldemar, Crete, 20-23 May 2019

  2. Outline • Some context/motivation: • The HR Diagram and basic properties • Dust and molecules around hot stars --- what do they tell us? • Complicated chemistry • Not a simple evolution of C/O abundances • Molecular diagnostics of chemistry, excitation, geometry • Conditions that SN Type II(n), Ib/c expand into chemically, physically. • SPICA observing parameter space • See F. Najarro poster #35 “Winds of Massive Stars with SPICA”

  3. Massive Stars on the HRD Molecules and Dust form and survive in spite of the most intense stellar UV radiation fields on the HRD 106 Red LBVs in quiescence LBVs in outburst L/L

  4. Spectral Evolutionary Sequences Upper end of the IMF: 1 in ~500,000 stars born with M(initial) ≿ 20 M O  WR  SN II or Ib/c Sander+ 2019. • WR lifetimes ~10% of massive O stars  ~5 Myr. • 2000-3000 expected in the MW, < 700 known. • LBV phase a few 104 to 105 years, eruptive mass loss few 10-3– 10-2 M/yr • 30 in the Milky Way + Magellanic Clouds, ~2 dozen candidates

  5. Various geometries can provide shielding from harsh X-Ray/UV stellar radiation fields for dust and molecules to form and survive.Binarity & mergers can play a role. LBV/pre-WR phase eruptions … WR  RSG + CSM interactions WR + O Wind-wind collisions NGC2359 WR7 WR104 WC+O Warm dust Carbon dust Callingham+ 2018 PAH 2' M1-67 WR7 HST/WFPC2 CO, CS, CN, HCN, HCO+ P=241 days Spitzer [4.5,8.0,24] m

  6. Various geometries can provide shielding from harsh X-Ray/UV stellar radiation fields for dust and molecules to form and survive. LBV/pre-WR phase eruptions … WR  RSG + CSM interactions WR + O Wind-wind collisions NGC2359 WR7 … clumped wind imprints or merger remnants? WR104 WC+O Warm dust Carbon dust Callingham+ 2018 PAH 2' M1-67 WR7 Spitzer 24 m CO, CS, CN, HCN, HCO+ P=241 days Morris+ 2019 Spitzer [4.5,8.0,24] m

  7. Dust Chemistry in evolved nebulae – Ejected mass strongly depends on chemistry • Massive cores go through CNO, triple- processing  H, C, N, O, …, and isotope abundances change • Dust chemistry reflects abundances in the mass-loss phase when grains condensed. This is a challenge to model! • More complicated than C/O < 1  C/O > 1 (cf. AGB stars). • Very metal-rich, possibly pure metal grains (Fe). • Ejectedmass is strongly depends on chemistry (+ grain properties) through Mdust ~ 1/. H present, N enhanced Spectral progression O V, Of, Ofpe, …, Of/WNL(h), WN(L/E), WN/WC, WC(L/E), WO SN RSG, BSG LBV  depends on M(init) No H, enhanced C, O SNtheoreticallypossible in any WR phase, LBV

  8. 10” Example: LBV  Carinae A “slow SN”, ~1054 ergs/s in 1840s, 1890s eruptions HST/WFPC2 Morse+ 1996 • F~  B(Td) ,  = emissivity •  = 1.22 (silicates) • Td = 400, 170, 110 K ( 10 K) • Md= F D2/()B(,Td) •  = grain absorption & scattering efficiencies weighted by grain size and density. • Olivines Md 0.15 M Morris+ 2017 70,000 Jy! Common empirical approach using astro-silicates or C-dust, broad-band continuum fitting How accurate is this approach?

  9.  Carinaemid-IR dust bandsISO SWS+LWS 1996/1997, Herschel SPIRE 2011 Morris+ 2017 SPIRE Ṁ = 1.5 ×10–3 M/yr M* = 120 M T*= 25 – 45 kK (Hillier+ 2001) amorphous + crystalline bands. What kind of dust chemistry can produce such bands?

  10.  Carinaebest-fit dust model DUSTY RT code (Ivezic+ 1999 ApJ) • Optical constants for > 50 amorphous & crystalline grain compositions. • No aqueous condensates, e.g. carbonates, clays, etc. • Spherical shells, size < 100 rmin. • Spherical MRN size distribution, r -2 density profile n(a)  a-3.5 , amin a  amax amin = 0.01 m, amax is free Model solution is not unique, many free parameters! The full IR spectra helps constrain chemistry, remove parameter degeneracies Only a few well-studied, good IR coverage: AG Car, Hen 3-591 (Voors+ 2000), LMC-R71 (Voors+ 1999, Morris+ 2005, Guha-Niyogi 2014) Dusty WC+O colliding wind binaries Morris+ 2017

  11. TypeIb/c Progenitors no H / no H, He MIPS 24 m M1-67 WR124 WN8 vrad 200 km/s Nebula mildly CNO-processed, LBV-like. Td 60 K a < 0.1 m  26 K 2-10 m • Md = 0.22 M • Olivines with 50/50 Fe/Mg • (Vamvatira-Nakou+ 2016) • Should be more like LBV-like chemistry? • Nature of the clumps unknown. • Molecular environment unknown. 3’ = 2.9 pc Bipolar (Nota+ 1995) or runaway bowshock(van der Sluys & Lamers 2003)? Clumped LBV wind imprint or merger remnant? MIPS 24 m G 2.40+01.40 WR102 WO [O IV] Triple- processed, enhanced C and O. Mixed dust chemistry, like post-AGB PNe? Nebula formation: PAH Spitzer/IRS T* = 200 kK v∞ = 5000 km/s R* = 0.53 R • Molecular cloud traced by CO 1-0 is impeding expansion to the SE (Dopita & Lozinskaya 1995; Arnal 2008). • Shell ejections during LBV/RSG phase? 13’ = 11 pc

  12.  Car’s molecular environmentCO  12C/13C abundances • Dust chemistry is consistent with CNO-processed material from the erupting star --- • low C, O (, Si), high N, Fe, other metals • Fe grains, metal-rich and O-deficient silicates, nitrides, sulfites. • No carbonaceous dust. • HIFI 12CO and 13CO 5-4 through 9-8 : <v> = 45 km/s Shocks + bulk motion Red = NLTE RADEX ISM: [CO/H2]  20×10-5 [12C/13C]  70 Morris+ 2017

  13. New Clues to SN II dust •  Car in the present day is a prototype SN Type II(n) progenitor– • Fe dust should be considered an important component in environments where high gas density can overcome low sticking probability. • Look also for an extended red wing to the 12 um feature, indicating nitrides and/or O-poor, Fe/Mg/Ca/Na-rich silicates. •  Many Galactic WRs and LBVs with low surface brightnesses, and resolved Local Group LBVs, WRs, “SN Imposters” are ideal for SMI, SAFARI • Progenitor SN Ib/c dust is still an open question… most too faint (dust too cool + low surface brightnesses) for Spitzer/IRS  current knowledge based on continuum fitting -- good spectra wanted!

  14. What about geometries? Est. > 70% of O stars are in binaries close enough for mass exchange affecting evolutionSana+ (2012, 2018); de Mink+ (2012) 71 • 71 O stars > 20 M observed in 6 Galactic clusters. • 40 spectroscopic binaries, +9 probable. • Clustered around P < 10 yr • Uniform distrib’n of masses • Merger rate ~30% “The most common end product of massive star evolution is an interacting binary.” The binary fraction and mass ratios (observed) and merger fraction (predicted) ~2-3x higher than stellar evolution theory predictions (cf. Zinnecker & Yorke 2007) Justham+ 2016: Is LBV activity due to mergers? Are “SN imposters” mergers?

  15.  Car’s dust torus / merger remnant? A present-day B I + WR/O, 5.54 yr period, e = 0.9 Originally a triple star, until 1890’s ? 10” [Ar III] PAH1 J7.9 [S IV]_1 [S IV] PAH2 [Ne II] [Ne II]_1 B12.4 VLT/VISIR April, May, December 2018 Burst-mode Small Field 0.075” pixel scale

  16. H2CN 3-2 13CO 2-1 VLT/VISIR Mehner+ 2019, Morris+ 2019 8.99 m 10.49 m 13.0 m ALMA 12CO 2-1 0  v  +200 km/s –200  v  0 km/s 6”

  17. A shielded molecule-rich environment Detections (so far): Loinard+ 2012, Morris+2017, 2019, Smith+ 2006, 2018 NH, N2H+,o/p-NH3, o/p-NH2 CN, H12CN, H13CN, HN12C, HN13C , H212CN, HCO+ 12CO, 13CO, CH+, OH+ HIFI, APEX large beams ALMA 0.5”-2.0” angular res. Tex= 75 – 325 K, N = few 1012 to 1014 cm-2 Inner 5”-7” NH NW lobe SE lobe N2H+ 6-5 through 11-10 NH2 NH3 N2H+ Morris+ 2019

  18. A shielded molecule-rich environment Detections (so far): Loinard+ 2012, Morris+2017, 2019, Smith+ 2006, 2018 NH, N2H+,o/p-NH3, o/p-NH2 CN, H12CN, H13CN, HN12C, HN13C , H212CN, HCO+ 12CO, 13CO, CH+, OH+ HIFI, APEX large beams ALMA 0.5”-2.0” angular res. Tex= 75 – 325 K, N = few 1012 to 1014 cm-2 NH • NH3, N2H+ abundances normal. • Competition for N from nitrides? • Other molecules (esp. HCN) thermodynamically favored? • NH, NH2 overabundant x10-100 compared to diffuse/translucent sightlines (Persson+ 2012, 2016) NH2 NH3 N2H+ Morris+ 2019

  19. More Chemistry Questions • By now many molecules are observed in the CSM around massive stars, formed by wind-ISM and wind-wind interactions. • What formation pathways? • E.g., CO detected around several hot massive stars. In the gas phase: • C+ + OH  CO+ + H, followed by either • (a) CO++ H  CO + H  substantially molecular • (b1) CO++ H2 HCO+ + H and (b2) HCO+ + e‒CO + H. • Different set of energetics! Path (b) probably favored around massive stars. • From the ground, studies of (mostly) low excitation reactants. • SAFARI gives access to a range of higher excitation energies. • CH+ J=1-0 also detected, formation via C+ + H2 requires E = 4250 K. • SARAFI gives access to the ladder from Jupper = 2 to 10, can help distinguish excitation by shocks vs UV irradiation.

  20. Water and Methanol! ALMA Herschel/HIFI H2O 1-1, 2-1 para CH3OH 10(2)-9(3) A vt = 0 Eu = 165 K ortho Tex = 100 (ortho) , 125 (para) K N = 3.5 (ortho), 0.25 (para) 1014 cm-2 Hydrogenated icy grain mantles, sputtering in heated gas?? (no ice detections) Gas phase reactions in shocked gas?? CH3+ + H2O  CH3OH2+ CH3OH2+ + e‒ CH3OH + H Main production pathway in shocks at high T (not very productive).

  21. Promises, promises… SPICA’s imaging spectrometers offer great opportunity to answer many dust + astrochemistryquestions for this population opened by ISO, Spitzer, Herschel, ALMA • Difficult for ISO and Spitzer spectrometers: low surface brightnesses low source and/or  sampling. • WRs, LBVc have increased in number by ~3 x since cold Spitzer via IR searches  Lots of new discovery space! • ~100+ with 24 m excesses, but no  > 3 m spectra • ~30 MIPS 24 / WISE W4 selected with cool CS nebulae • No FIR/Herschel • 10+ arcmin diameter •  ideal for SMI camera mode • Spectral mapping at SAFARI sensitivities • CO low J lines only 10s of mJy/sr, will be stronger at higher J for Tex = 150-350 K. WISE survey Faherty+ 2014

  22. Promises, promises… • SMI low-med res spectra. • Coverage of key dust bands in camera mode (10’x12’) to 38 m ideal for many recent CS nebula detections. • Coverage of silicate/nitride band is desirable, starting at 12 m… but only narrow-slit, high res available. •  JWST/MIRI, SOFIA • Redshift  1.25 to get full coverage  > 8 m   > 18 m

  23. Thank You ευχαριστώ !

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