热改正

热改正的数学表达式为：

${\displaystyle BC=M_{v}-M_{bol}\!\,}$

下表列出对具有不同光谱类型和分类的一系列恒星的热改正：

对于早型星和晚型星，热改正都为偏大的负数。前者是因为早型星表面温度较高，辐射出射的很大一部分是在紫外波段的；后者则是因为晚型星表面温度较低，辐射出射很大一部分在红外波段。对于像我们的太阳这样的恒星，热改正是微不足道的，因为太阳的辐射出射集中在可见光波段。热改正是对天体的绝对星等进行的校正，以将天体的绝对目视星等转换为其热星等。

类似的，热改正可以用于可见光波段之外的其他电磁波段改正为热星等。例如，对于某些领域内常见的辐射出射集中在红外波段范围内的、表面温度较低的恒星，热改正有时采用一套不同的值以改正红外波段的绝对星等，而非绝对目视星等。

在数学上，这样的改正值可以表示为：

${\displaystyle BC_{K}=M_{k}-M_{bol}\!\,}$

其中M _K是K波段的绝对星等， BC _K是K波段的热改正值。

• 绝对星等
• K波段（红外）
• V波段

• https://github.com/casaluca/bolometric-corrections - most up to date tables of bolometric corrections across the HR diagram and interpolation routines in different photometric filters
• https://web.archive.org/web/20080312151621/http://www.peripatus.gen.nz/Astronomy/SteMag.html - contains table of bolometric corrections
• http://articles.adsabs.harvard.edu//full/1996ApJ...469..355F/0000360.000.html - contains detailed tables of bolometric corrections (note that these second set of tables are consistent with a bolometric magnitude of 4.73 for the Sun and also be aware that there are misprint errors for a few of the figures in the tables)

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2. Humphreys, R. M.; McElroy, D. B. . The Astrophysical Journal. 1984, 284: 565–577. Bibcode:1984ApJ...284..565H. ISSN 0004-637X. doi:10.1086/162439 （英语）.
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4. Bessell, M. S.; 等. . Astronomy and Astrophysics. May 1998, 333: 231–250. Bibcode:1998A&A...333..231B.
5. Salaris, Maurizio; 等. . Monthly Notices of the Royal Astronomical Society. November 2002, 337 (1): 332–340. Bibcode:2002MNRAS.337..332S. arXiv:astro-ph/0208057. doi:10.1046/j.1365-8711.2002.05917.x. Lower effective temperatures correspond to higher values of ${\displaystyle \scriptstyle BC_{K}}$; since ${\displaystyle \scriptstyle M_{K}=M_{bol}-BC_{K}\!\,}$, cooler RC stars tend to be brighter.
6. Buzzoni, A.; 等. . Monthly Notices of the Royal Astronomical Society. April 2010, 403 (3): 1592–1610 . Bibcode:2010MNRAS.403.1592B. arXiv:1002.1972. doi:10.1111/j.1365-2966.2009.16223.x.