Questions tagged [interferometry]
Questions about astronomical observations which involve superimposing waves received by multiple, physically separated, receivers to obtain higher angular resolution.
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Estimate the number of pixels required to map the full primary beam of a Radio Telescope station
I am practising some exam questions for a radio interferometry exam, and I am struggling with this question:
The physical size of a single LOFAR station, operating at 150MHz is about 50m.
Estimate ...
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Convert from Jy/beam km/s to W/m$^2$
I need to compare some ALMA observations of a protoplanetary disk to disk-integrated fluxes obtained from a model.
The ALMA observations are upper limits of non-detected spectral lines, where the RMS ...
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How is VLBI delay calculated?
I’m working on a research project wherein we are trying to solve a problem very similar to VLBI delay. We have two radio receivers, and we know their locations. We also know at what time one receiver ...
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How does speckle imaging fit in to 21st century high resolution imaging from ground based observatories?
Phys.org's Astronomers uncover evidence that there could be many more Earth-sized planets than previously thought references Speckle Observations of TESS Exoplanet Host Stars. II. Stellar Companions ...
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Is Optical VLBI theoretically feasible? If not why not?
There are plenty of optical interferometers in use with baselines of up to maybe 1km. As far as I can find out, they all work by directly collecting the light at all the telescopes, using mirrors to ...
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Would "layered" radio interferometry work?
tl;dr - Is splitting up the process of interferometry as shown in the diagram possible, and if so, is it more efficient and/or easier than traditional methods?
I have been doing some research into ...
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Has optical interferometry been done at radio frequency using heterodyning with a laser in a nonlinear material?
If one collects narrow band optical emission from a large telescope with frequency $f_1$ and mixes it in a nonlinear crystal with laser light of a nearby frequency $f_2$, it would produce two new ...
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What could a cloud of mini radio dishes see?
Suppose an astronomer gave a 1 m radio dish to 500 people scattered over the face of the Earth and connected them to the internet. The people are directed to set their radio antennae up in their ...
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What is the significance of using baseline pairs in radio interferometry?
Radio interferometry utilizes arrays of smaller telescopes that are linked together to synthesize a larger aperture telescope. Astronomical radio observatories, such as the Very Large Array in New ...
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What is the role of the mesh on which dipole elements of the MWA antennas are placed?
I was reading about the radio telescope - Murchison Widefield Array (MWA) situated in Western Australia. Antennas of this telescope are quite unique and different from the usual dish radio telescope. ...
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What are the raisons d'être for the Large Binocular Telescope "binocularity"?
edit: The short form of the question is Why are there TWO telescopes?? A longer version follows.
The Large Binocular Telescope (and LBT blog as source of images below) has two 8.4 meter diameter ...
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In astronomical interferometry, what values do the points in the uv-plane have?
As I understand it, the image of an interferometer is the inverse fourier transform of the information in the uv plane. For each baseline (vector between any two telescopes in the array), representing ...
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What are the challenges for the building and data analysis of the CHIME telescope?
The Canadian Hydrogen Intensity Mapping Experiment (CHIME) has discovered the second repeated fast radio burst recently. However, its structure is simple apparently. I wonder why we did not build a ...
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Why don't we use amateur astronomers' telescopes to create a huge interferometer?
Some telescopes in space have been proposed to function as an interferometer.
Being placed several hundreds or thousands of kilometers apart they could actual image exoplanets directly. To my ...
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The role of 'the interference of waves' in VLBIs'
I've been trying to find out how VLBIs work. It says in this book I've read that many radio telescopes around the world work in tandem to use the interference of waves to get a clearer picture of ...
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