Questions tagged [dispersion]
The dispersion tag has no usage guidance.
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Why does the velocity dispersion within a galaxy cluster decrease as a function of radius?
In the paper 10.1093/mnras/sty2379, there are plots showing the velocity dispersion as a function of radius.
Focusing on the right-hand plot, non-merging normal clusters, intuitively why should the ...
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The preferred way of binning (classifying) data for galaxy snapshots in Python
Let's say I have a galaxy snapshot that I load with some package (pynbody etc) and I store my spatial coordinates of stars in the galaxy in x, y, z arrays and also velocity in array vz. Now I want to ...
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When measuring the spectrum of an object at the zenith, is it better to orient the spectroscopic slit N-S of E-W?
If you were to measure the spectrum of an object while it's exactly at the zenith, how should you orient the slit of the spectrograph to minimise atmospheric dispersion? Is North-South or East-West ...
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How hard is it to find the Sun's "sisters?"
As @ProfRob stated in his excellent answer regarding the ejection of the Solar System's fifth gas giant,
It is for similar reasons that, even though the Sun was probably born in a cluster of $\sim 10^...
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Understanding energy loss in a telescope aperture due to atmospheric dispersion
I'm trying to understand energy losses due to atmospheric dispersion, given the plot below from the Keck telescope.
For a typical seeing I'm told that there's 80% encircled energy in 1". The ...
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Do ASKAP and ALMA have "fast dump" interferometric modes? Can they see and perhaps report Fast Radio Bursts in real time?
Chatterjee et al 2017 The direct localization of a fast radio burst and its host nicely shows a VLA detection of a repeating FRB in 5 millisecond steps nicely demonstrating the dispersion slope ...
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