The Complex Upper HR Diagram
Abstract
:1. Introduction
2. Early Work—The Magellanic Clouds
3. The HR Diagram
4. The Humphreys–Davidson Limit
5. Surveys and More Surveys
6. Stellar Population Comparisons
7. The Most Luminous Stars of Different Types
8. The Complex Upper HR Diagram
Funding
Conflicts of Interest
References
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Galaxy Type Mv | M31 Sb I–II −21.5 | M33 Sc II −18.9 | LMC Im −18.5 | SMC Im −16.8 | NGC 6822 Im −15.2 | IC 1613 Ir −14.8 | NGC 2403 Sc III −19.3 | M81 Sb I–II −20.9 | M101 Sc I −21.0 |
---|---|---|---|---|---|---|---|---|---|
Spectral Type | M | M | M | M | M | M | M | M | M |
O9.5–B5 | −10.6(2) | −10.1 | −10.9 | −10.3(2) | −10.3 | −9.5 | −10.0(2) | −10.6 | ... |
−10.2 | −10.0 | −10.7 | −10.2 | −9.9 | −8.8 | −9.5 | −10.0 | ... | |
−10.0(2) | −9.8 | −10.0 | −9.8(2) | −9.5 | −8.7 | −9.4 | −9.7 | ... | |
B8–A8 | −9.3 | −10.1(B324) | −9.6(HD33579) | −9.6(HD7583) | −8.1 | −8.4 | −9.8 | −9.3 | −10.4(2) |
−9.1 | −9.5(2) | −9.0 | −9.2 | −7.7 | −6.9 | −9.5 | −9.1(2) | −10.3 | |
−8.9(2) | −9.4 | -8.9 | −9.0 | −7.5 | −6.7 | −9.4 | −8.9 | −9.9 | |
FGK | −9.8 | −9.6(2) | −9.3 | −9.2 | ... | ... | −9.3 | −9.7 | −9.8 |
−9.7 | −9.5(Var A) | −9.2 | −9.1 | ... | ... | −8.8 | −9.6 | −9.3 | |
−9.5 | −9.2(3) | −8.9(3) | −8.1 | ... | ... | −8.5 | −9.4 | −9.2 | |
RSGs | −9.4(2) | −9.6 | −9.6(MOH-G64) | −9.2 | −9.2 | −9.4 | −8.5 | −9.5: | −9.9: |
−9.3 | −9.5(2) | −9.1 | -9.1 | −9.1 | −8.8 | −8.4(2) | −9.2(2) | −9.5 | |
−9.1(2) | −9.4(2) | −9.0 | −8.9 | −8.7 | −8.7 | ... | ... | −9.2 |
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Humphreys, R.M. The Complex Upper HR Diagram. Galaxies 2019, 7, 75. https://doi.org/10.3390/galaxies7030075
Humphreys RM. The Complex Upper HR Diagram. Galaxies. 2019; 7(3):75. https://doi.org/10.3390/galaxies7030075
Chicago/Turabian StyleHumphreys, Roberta M. 2019. "The Complex Upper HR Diagram" Galaxies 7, no. 3: 75. https://doi.org/10.3390/galaxies7030075