Table A.1.
Numbers of certain types of stars and SFRs in different galaxies.
| Galaxy | SFR (lit.) | NHeB, lit. SFR | NcSG, obs | SFRmin | NcSG, pred | NcSG, obs | NWR, obs |
|---|---|---|---|---|---|---|---|
| [M⊙ yr−1] | (5< logL< 5.6) | (5< logL< 5.6) | [M⊙ yr−1] | (logL> 5.6) | (logL> 5.6) | (logL> 5.6) | |
| I Zw 18 | 0.1-1 | 150-1500 | 28 | 0.019 | 90 (10a)) | 0 | "tens" (estimated, no L provided) |
| SMC | 0.05 | 75 | 41b) | 0.027 | 32 | 0 | 11 (3 can be H-burningc)) |
| NGC 5253 | 0.1, 0.2 | 150, 300 | 71 | 0.047 | 52 | 1 | 30 to 40 (estimated, no L provided) |
| LMC | 0.2 | 300 | 72b) | 0.048 | 21 | 1 | ∼80 (half can be H-burningc)) |
| NGC 300 | 0.08-0.16 | 120-240 | 86 | 0.057 | 21 | 0 | 30 to 40 (estimated, no L provided) |
| NGC 4395 | 0.03, 0.5 | 45, 750 | 86 | 0.057 | 19 | 0 | "WR features" |
| M 31 | 0.7 | 1050 | 117d) | 0.078 |
Notes. The text in Appendix A.1 describes how numbers of cool SG stars and the minimum SFRs are obtained. Explanation of notes in the table: a): if, instead, a constant cool SG lifetime fraction of 7% of the stellar lifetime is assumed – b): from Davies et al. (2018) – c): these stars can be hydrogen burning because they have temperatures lower than the zero-age main-sequence temperature. – d): from McDonald et al. (2022). Literature SFR references are the following. I Zw 18: table 1 of Hirschauer et al. (2024), Bortolini et al. (2024); SMC: Harris & Zaritsky (2004); N5253: López-Sánchez et al. (2012); LMC: Harris & Zaritsky (2009); N300: Helou et al. (2004), Kang et al. (2025); N4395: Smirnova et al. (2020), Nandi et al. (2023); M31: Lewis et al. (2015). References for NWR, obs: Sect. 5.3.4, and Hainich et al. (2014, 2015) for LMC and SMC, respectively.
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.