“BC03”的版本间差异

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无编辑摘要
无编辑摘要
第3行: 第3行:
:AIRTOVAC可转换
:AIRTOVAC可转换
*3323-9301是高分辨率,1A
*3323-9301是高分辨率,1A
*


*As noted by Asari et al. (2007), the Bruzual & Charlot (2003) models have a low amplitude hump in the ∼100 Å interval around
*As noted by Asari et al. (2007), the Bruzual & Charlot (2003) models have a low amplitude hump in the ∼100 Å interval around
Hβ, such that Hβ emission often sits in a slightly negative valley in the observed minus model spectrum (an artefact of the STELIB
Hβ, such that Hβ emission often sits in a slightly negative valley in the observed minus model spectrum (an artefact of the STELIB
library, which disappears when using models based on the MILES library of Sanchez-Bl ´ azquez et al. 2006). Asari et al. (2007) found ´
library, which disappears when using models based on the [[MILES]] library of Sanchez-Bl ´ azquez et al. 2006). Asari et al. (2007) found ´
this effect to be unimportant for their Hβ measurements, but their analysis focused on SF galaxies, which tend to have strong Hβ. Here
this effect to be unimportant for their Hβ measurements, but their analysis focused on SF galaxies, which tend to have strong Hβ. Here
it has a larger impact, since we are specifically interested in galaxies with intrinsically weak Hβ. To alleviate this problem, the Hβ flux
it has a larger impact, since we are specifically interested in galaxies with intrinsically weak Hβ. To alleviate this problem, the Hβ flux

2024年6月30日 (日) 08:47的版本

  • AIR 波长,SDSS的谱是真空波长
AIR = VAC / (1.0 + 2.735182E-4 + 131.4182 / VAC^2 + 2.76249E8 / VAC^4)
AIRTOVAC可转换
  • 3323-9301是高分辨率,1A
  • As noted by Asari et al. (2007), the Bruzual & Charlot (2003) models have a low amplitude hump in the ∼100 Å interval around

Hβ, such that Hβ emission often sits in a slightly negative valley in the observed minus model spectrum (an artefact of the STELIB library, which disappears when using models based on the MILES library of Sanchez-Bl ´ azquez et al. 2006). Asari et al. (2007) found ´ this effect to be unimportant for their Hβ measurements, but their analysis focused on SF galaxies, which tend to have strong Hβ. Here it has a larger impact, since we are specifically interested in galaxies with intrinsically weak Hβ. To alleviate this problem, the Hβ flux measurements were performed with respect to a local ‘continuum’ in the residual spectrum. No such systematic residual is found for other emission lines, whose measurement does not require the extra care devoted to Hβ.