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Ew(Hα) of one star forming galaxy - 版本历史
2026-05-14T22:33:29Z
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http://cluster.shao.ac.cn/wiki/index.php?title=Ew(H%CE%B1)_of_one_star_forming_galaxy&diff=244&oldid=prev
2013年12月24日 (二) 02:02 Cluster
2013-12-24T02:02:27Z
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">2013年12月24日 (二) 02:02的版本</td>
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<td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del> Equivalent Width : EW(Hα)</div></td>
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<td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">===</ins> Equivalent Width : EW(Hα)<ins style="font-weight: bold; text-decoration: none;"> ===</ins></div></td>
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<td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Recall EW(Hα) measures the relative strength of Hα to the continuum under the line </div></td>
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<td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Recall EW(Hα) measures the relative strength of Hα to the continuum under the line </div></td>
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<td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>It therefore acts like a long baseline color index UV(Hα)<--> λ6550 A </div></td>
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Cluster
http://cluster.shao.ac.cn/wiki/index.php?title=Ew(H%CE%B1)_of_one_star_forming_galaxy&diff=243&oldid=prev
Cluster：以“* Equivalent Width : EW(Hα) Recall EW(Hα) measures the relative strength of Hα to the continuum under the line It therefore acts like a long baseline color index...”为内容创建页面
2013-12-24T01:41:05Z
<p>以“* Equivalent Width : EW(Hα) Recall EW(Hα) measures the relative strength of Hα to the continuum under the line It therefore acts like a long baseline color index...”为内容创建页面</p>
<p><b>新页面</b></p><div>* Equivalent Width : EW(Hα)<br />
Recall EW(Hα) measures the relative strength of Hα to the continuum under the line <br />
It therefore acts like a long baseline color index UV(Hα)<--> λ6550 A <br />
<br />
Although it cannot be converted to a current SFR, it has another important use : <br />
It measures the ratio of the current SFR (from Hα) to the integrated past SF (from the continuum) <br />
Using synthesis models, this relation can be quantified, to give : <br />
EW(Hα)--> (current SFR) / (mean past SFR) ; written SFR/<SFR> or "b" <br />
http://www.astro.virginia.edu/class/whittle/astr553/Topic11/Lecture_11.html<br />
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*</div>
Cluster