Plasma Diagnostics for Planetary Nebulae and H II Regions                                                                 ...
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Plasma diagnostics for planetary nebulae and H II regions using N II and O II

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Poster presented by Ian McNabb at the IAU Symposium 283, Planetary Nebulae: an Eye to the Future, 25-29 July 2011, Tenerife, Spain.

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Plasma diagnostics for planetary nebulae and H II regions using N II and O II

  1. 1. Plasma Diagnostics for Planetary Nebulae and H II Regions using N II and O II Optical Recombination Lines I. McNabb1, X. Fang1, X.W. Liu1,2, P.J. Storey3 1. Kavli Institute of Astronomy and Astrophysics at Peking University 2. Department of Astronomy at Peking University 3. Department of Physics and Astronomy at University College London 500 500 Abstract -- We carry out plasma diagnostic analysis for a number of planetary nebulae (PNe) and H II regions. We use N II and O II 500 500 Iobs = 0.0652 Iobs = 0.1355 Iobs = 0.6664 Iobs = 0.2174 obs= 0.0043 obs= 0.0065 obs= 0.0089 obs= 0.0140 optical recombination lines (ORLs) with new effective recombination coefficients calculated under the intermediate coupling scheme, 400 Nsim = 10000 Imean = 0.0651 400 Nsim = 10000 Imean = 0.1355 400 Nsim = 10000 Imean = 0.6665 400 Nsim = 10000 Imean = 0.2172 for a range of electron temperatures (Te) and densities (Ne), and fitted against the most reliable measurements. Comparing Te derived 300 mean = 0.0043 Ifit = 0.0652 300 mean = 0.0065 Ifit = 0.1355 300 mean = 0.0088 Ifit = 0.6664 300 mean = 0.0140 Ifit = 0.2173 fit = 0.0043 fit = 0.0066 from ORLs, collisionally excited lines (CELs), the hydrogen Balmer Jump, and/or He I if available, we find the relation Te (ORLs) < fit = 0.0089 fit = 0.0140 # # # # Te (He I) < Te (H I BJ) < Te (CELs), confirming the physical conditions in the two-abundance model postulated by Liu et al. (2000), 200 200 200 200 i.e. the nebula contains another cold, metal-rich and probably H-deficient component. 100 100 100 100 Methodology -- For N II ORLs, the effective recombination coefficients covered a log Te range from 2.1 to 4.3 [K], with a 0.1 0 0.04 0.05 0.06 0.07 0.08 0.09 0 0.11 0.12 0.13 0.14 0.15 0.16 0.17 0 0.62 0.64 0.66 0.68 0.70 0.72 0 0.14 0.16 0.18 0.20 0.22 0.24 0.26 0.28 increment, and a log Ne range from 2 to 6 [cm-3], also with a 0.1 increment. For O II ORLs, the effective recombination coefficients I (V3 5666) I (V3 5679) I (V1 4649) I (V1 4661) covered a log Te range from 2.6 to 4.2 [K], with a 0.2 increment, and a log Ne range from 2 to 5 [cm-3], also with a 0.2 increment, and 500 Iobs = 0.0819 obs= 0.0051 500 Iobs = 0.0371 obs= 0.0071 500 Iobs = 0.2654 obs= 0.0048 500 Iobs = 0.0921 obs= 0.0066 later bilinearly interpolated to a resolution of 0.05 [K] by 0.05 [cm-3]. The location of the minimum χ2 value corresponded to the 400 Nsim = 10000 Imean = 0.0819 400 Nsim = 10000 Imean = 0.0370 400 Nsim = 10000 Imean = 0.2655 400 Nsim = 10000 Imean = 0.0922 mean = 0.0051 mean = 0.0070 optimal Te and Ne for each wavelength combination of the observed intensities. Fig. 1 shows the log χ2-distributions for 8 PNe and 1 H 300 Ifit = 0.0819 fit = 0.0051 300 Ifit = 0.0371 fit = 0.0070 300 mean = 0.0048 Ifit = 0.2654 300 mean = 0.0066 Ifit = 0.0922 fit = 0.0049 fit = 0.0066 II region (Hf 2-2, M 1-42, NGC 6153, and M 2-36, NGC 7009, NGC 6543, IC 4191, M 3-32, and M 42), matching the archived data # # # # 200 200 200 200 for each nebula against the theoretical predictions from each wavelength. Once the optimal Te and Ne were located for each PN, the comparison was also calculated for each combination of simulated 100 100 100 100 intensities within a 1-σ Gaussian distribution confined to the errors of the observed intensities. Fig. 2 shows the Gaussian-distributions 0 0.06 0.07 0.08 0.09 0.10 0.11 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0 0 0.24 0.25 0.26 0.27 0.28 0.29 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 for N II and O II wavelengths within 1-σ of the observed intensities. The optimal Te and Ne locations for each simulation would I (V39b 4041) I (V39a 4035) I (V48a 4089) I (V48c 4087) provide the error estimates of the optimal Te and Ne from the observed intensities. The randomly generated intensities were combined Fig. 2: (left 4 panels) Normal distributions for 10,000 simulations for 4 N II ORLs. (right 4 panels) Same for each simulation and compared with the theoretical predictions based on the effective recombination coefficients for each for 4 O II ORLs. The black curve represents the Gaussian profile from observed intensities and errors. wavelength covering a range of temperatures and densities. Fig. 3 shows the frequencies of the optimal Te and Ne locations derived The blue curve is from the mean intensities and errors. The red curve is created from fitting. from the simulated intensities. a) Hf 2-2 (2as) (XWL06) adf (O2+) = 84: b) M 1-42 (XWL01) adf (O2+) = 22: c) NGC 6153 (XWL00) adf (O2+) = 9.2: a) Hf 2-2 (2as) (XWL06) adf (O2+) = 84: b) M 1-42 (XWL01) adf (O2+) = 22: c) NGC 6153 (XWL00) adf (O2+) = 9.2: Iobs( 5666) + Iobs( 5679) + Iobs( 4041) + Iobs( 4035) Iobs( 5666) + Iobs( 5679) + Iobs( 4041) + Iobs( 4035) Iobs( 5666) + Iobs( 5679) + Iobs( 4041) + Iobs( 4035) Iobs( 4649) + Iobs( 4661) + Iobs( 4089) + Iobs( 4087) 5.0 2 log 2 log 2 log 2 log Iobs( 4649) + Iobs( 4661) + Iobs( 4089) + Iobs( 4087) log 2 Iobs( 4649) + Iobs( 4661) + Iobs( 4089) + Iobs( 4087) log 2 1.939 1.011 1.102 1.068 1.393 1.314 4.0 1.654 4.0 0.738 4.0 0.804 4.0 0.731 4.0 1.045 4.0 0.913 [O III] 1.369 0.466 0.507 0.395 0.697 0.512 H I BJ He I ( 7281/ 6678) NGC 6543 1.084 0.193 0.210 0.059 0.348 0.111 3.5 3.5 3.5 O II IC 4191 fixed 0.798 -0.080 -0.088 -0.277 -0.000 -0.290 3.5 3.5 3.5 4.5 N II log Te log Te log Te log Te log Te log Te 0.513 -0.353 -0.385 -0.613 -0.349 -0.692 NGC 7009 NGC 6153 M 42 Hf 2-2 2as 3.0 0.228 3.0 -0.625 3.0 -0.683 -0.950 -0.697 -1.093 M 3-32 M 2-36 M 1-42 -0.057 -0.898 -0.980 -1.286 -1.046 -1.494 3.0 3.0 3.0 2.5 -0.342 2.5 -1.171 2.5 -1.277 -1.622 -1.394 -1.895 -0.627 -1.444 -1.575 -1.958 -1.742 -2.296 2 3 4 log Ne 5 6 -0.912 2 3 4 log Ne 5 6 -1.716 2 3 4 log Ne 5 6 -1.872 2.0 2.5 3.0 3.5 log Ne 4.0 4.5 5.0 -2.294 2.0 2.5 3.0 3.5 log Ne 4.0 4.5 5.0 -2.091 2.0 2.5 3.0 3.5 log Ne 4.0 4.5 5.0

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