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Integral Field Spectroscopy of Orion Proplyds: Metallicity and Other

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Integral Field Spectroscopy of Orion Proplyds: Metallicity and Other Integral field spectroscopy of Orion proplyds: metallicity and other proper7es Yiannis Tsamis (ESO) Nahiely Flores-Fajardo (UNAM Morelia/Beijing) Will Henney (UNAM Morelia) Adal Mesa-Delgado (Univ Chile) Daniel Pequignot (Meudon/Paris) Pepe Vilchez (IAA Granada) Jeremy Walsh (ESO) Proplyds in Orion LV 2 • Adapted from Bally et al: HST WFPC2 (blue) + NICMOS (red: 2.15um cont + H2 line emission). H2 emission from slow C-type shocks 20-40 km/s (Colgan et al. 2007) The Orion Nebula proplyds • The Sun was born in an Orion type cluster (Adams 2010) • Orion is distant (410 pc), but it contains massive hot stars capable of ionizing the proplyds. • Bright emission lines: plasma diagnoscs, metallicity probes. HST Hα (Bally et al 2000)# Coronal abundances of X-ray eming pre-main sequence Orion sources (Maggio et al. 2007) S O Ar Ne Fe •! S, O, Ar, Ne Solar agree with B- stars and the Orion Nebula gas abundances •! Mg, Fe depleted compared to Solar and stellar values by up to ~few Observaonal challenges: Keck HIRES long slit spectra of proplyds •! It is difficult to subtract the uneven nebular background and isolate the proplyd intrinsic emission with long slit methods •! Anomalous line profiles can be obtained: Henney & O’Dell (1999) background subtrac[on issues? The LV2 archetype - HST FOS single-aperture spectra HST Hα+[NII] - OʼDell & Wen (1994)# C2+ UV O+ C+ C = C+ + C2+ Optical O = O+ + O2+ $1Ori C# O2+ 3 circular HST FOS apertures (0.26”) within the 6.6”x4.2” VLT FLAMES/Argus IFU field (dashed box) Tsamis et al. (2011), MNRAS, 412, 1367 # Integral field spectroscopy of LV2 (VLT FLAMES/Argus IFU) With IFU observations the background is still non-uniform but we have more room to move and to try and define it around a proplyd Top left: O II 4649 recombination line – O2+ Top right: [O III] 5007 – O2+ Bottom left: [N II] 6584 – N+ Bottom right: [S II] 6731 – S+ Tsamis et al. (2011) Plasma physical condions: electron temperature and density From observed line raos of temperature and density-sensi[ve collisionally excited lines and comparing with theore[cal raos LV2 proplyd Temperature ~ 9000 K, Density ~ 106 cm-3 HST10 proplyd Temperature ~ 9000 K, 4 -3 Density ~ 3 x 10 cm Abundance analysis based on collisionally excited lines (“forbidden lines”) [O III], [O II] , [N II], [S III] , [S II], [Ar III], [Ne III], etc. CII and OII recombina7on lines (RLs) from protoplanetary disks: novel metallicity diagnoscs •! This is the first detec[on from proplyds: prominent in planetary nebulae and HII region spectra (e.g. Liu et al. 2000; Tsamis et al. 2003, 2008; Esteban et al. 2004, 2005). •! They are weak (<1% of Hbeta) but can be accurately measured in deep spectra. •! Atomic data for their analysis exists since the 1990s (Pequignot et al. 1991; Storey et al. 1994; Liu et al 1995; Davey et al. 2000; Storey in prep.) •! Abundances relave to H are a very weak func[on of temperature and density, hence, in principle, “bias-free” VLT FLAMES/Argus (R~12000) Abundances in LV 2 vs. Orion HIIR vs. Sun Proplyd Orion HIIR Sun (photosphere) B-stars (Simon-Diaz’10) C = 8.35 N = 7.82 O = 8.74 Ne = 8.09 Tsamis et al. (2011) •! Super-solar values by factors of: C (x 2 – 3), O (x 2), Ne (x 2) •! The Ne/S rao is > 2x Solar • Iron is 0.3% Solar (−2.5 ! dex) and 9% of the Orion gas value. Dust deple[on similar to that seen towards cold ISM sightlines. àEvidence for grain growth? Iron in solids? The jet of LV2 (VLT/FLAMES) (Tsamis & Walsh 2011) •! Spaally and spectrally resolving LV2’s bipolar jet (200 AU peak to peak) •! Fe/H (in jet lobe) ≥ 30-50% Solar Grains destroyed in shocks, iron is ejected into the gas phase Oxygen in the Universe HST 10 in Orion [O I] 5577 emitted from the surface of the disc Carbon recombination line EUV/ FUV photon Dynamic photoevaporation/photoionization Ionization models (based on Cloudy) used to front match the observations self-consistently: Photoevaporation age ~ 104 yr, much shorter than age of Orion nebula, >105 yr: (i) Either the disc masses have been severely underestimated, or/and (ii) Discs were shielded from UV until recently (Tsamis et al. 2013) Results so far… •! HST 10 shows solar oxygen, and C, O, Ne that are practically the same as in B-type Orion stars. Fe is 0.2 dex lower than in M42 and 0.7 dex less than solar (empirical and model analysis – Tsamis et al 2013). •! LV2 shows elevated C, O, Ne compared to solar and to B-stars; Fe is 2.5 dex less than solar (empirical analysis, Tsamis et al 2011; Tsamis & Walsh 2011; models in preparation). •! HST 1 shows sub-solar O, and Fe 1.8 dex less than solar, but the analysis could not fully account for O+ as [O II] lines were not detected (empirical + model; Mesa-Delgado et al 2012). •! Sample is being enlarged with several other proplyds in Orion. •! VLT/SINFONI nIR IFU and X-shooter datasets under analysis/ construction .
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