Free Access

Table 4

Scattered and in situ emission line ratios.

Line ratio Scattered In situ Brandt & Madsen et al. (2006) Witt et al.
TPN & DC 303 TPN DC 303 Mean Draine (2012) HII reg WIM (2010)
(1) (2) (3) (4) (5) (6) (7) (8) (9)

[S ii]/(Hα+[N ii]) 0.31 ± 0.05 0.52 0.50 0.51 0.46 0.14 0.7 0.31
(Hα+[N ii])/ Hβ 5.4 3.5 3.5 3.5 4.5
 [N   ii] / Hβa 0.7 0.7 0.7 1.9
 [N   ii] / Hαa 0.2 0.2 0.2 0.72 0.36 0.7

Notes. The [N ii]/Hβ ratios for the in situ case were calculated by assuming a ratio Hα/Hβ = 2.87 corresponding to case B for T = 10   000 K and no extinction (Osterbrock & Ferland 2006). The [N ii] line strengths include λ6583 and λ6548 lines and [S ii] includes λ6716 and λ6731 lines. In Madsen et al. (2006) and Witt et al. (2010) the values are for single lines λ6583 and λ6716 and were modified here corresponding to the line ratios.

(a)

assuming Hα/Hβ = 2.87.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.