<p>Such surveys are designed to detect an excess of emission over that expected from a stellar photosphere.</p>

<p>The emission from a circumstellar disk is often modelled as a blackbody at lower temperature than the stellar photosphere. A hotter blackbody with the same emitting area emits more flux than a cooler blackbody at <em>all</em> wavelengths.</p>

<p>Therefore, if you had a disk of fixed emitting area, it would be <em>easier</em> to detect a hotter disk at sub-mm wavelengths than a cooler disk.</p>

<p>However, if you have a lot of cold disk material and no warmer regions, then because the Wien tail of the blackbody distribution is so steep, it emits almost no radiation at near- and mid-infrared wavelengths, and sub-mm detection is the best way to detect it.</p>

CC BY-SA 4.0
2019-10-27T08:24:06.497Z
2019-10-27T08:24:06.497Z
ProfRob
<p>At these wavelengths a survey is more sensitive to detecting relatively cool disks (T&lt;100k), but would a telescope operating in the sub-millimeter be less sensitive to warm debris disk than say, a mid IR telescope?</p>

<star><planet><exoplanet><disk><proto-planetary-disk>
Are warm circumstellar debris disks still able to be detected at sub-millimeter wavelengths?
Joshua
# Are warm circumstellar debris disks still able to be detected at sub-millimeter wavelengths?

(Asked by: username_0 on 2019-10-27)

At these wavelengths a survey is more sensitive to detecting relatively cool disks (T<100k), but would a telescope operating in the sub-millimeter be less sensitive to warm debris disk than say, a mid IR telescope?

**Tags:** star, planet, exoplanet, disk, proto-planetary-disk

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## 1 answers

### Answer by username_1 on 2019-10-27. Score: 3 | Accepted answer

Such surveys are designed to detect an excess of emission over that expected from a stellar photosphere.

The emission from a circumstellar disk is often modelled as a blackbody at lower temperature than the stellar photosphere. A hotter blackbody with the same emitting area emits more flux than a cooler blackbody at *all* wavelengths.

Therefore, if you had a disk of fixed emitting area, it would be *easier* to detect a hotter disk at sub-mm wavelengths than a cooler disk.

However, if you have a lot of cold disk material and no warmer regions, then because the Wien tail of the blackbody distribution is so steep, it emits almost no radiation at near- and mid-infrared wavelengths, and sub-mm detection is the best way to detect it.


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