Questions tagged [dispersion]

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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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3 votes
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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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