Questions tagged [radio]
Questions about the part of the electromagnetic spectrum with wave lengths longer than those of infrared radiation.
12
questions with no upvoted or accepted answers
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What EM spectrum can stars be most cheaply observed using Remote Sensing during the day?
I would like to augment my GPS navigation with remote sensing of 'the sky.' I am looking for any astronomical body that can be perceived during the day.
Maybe Pulsars emit something easily detected, ...
4
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40
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Fitting a line or polynomial to optical and radio SEDs
I've been trying to fit functions to plots showing photometric data for AGN from both optical and radio measurements, such as:
but my supervisor says that this shouldn't be done; the radio and ...
4
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0
answers
32
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How are shockwaves used to study magnetic fields of merging galaxy clusters?
Recently i read an article about how a shockwave 60 times larger than milky way galaxy is generated.When these shockwaves interacts with magnetic field, radio waves are emitted. I wanted to know how ...
3
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828
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Radiometer Equation for Flux Density
In Duncan and Lorimer's Handbook of Pulsar Astronomy, the equation for the flux density using a radio telescope is given as (for a top-hat function):
$$S=\frac{\beta\,\mathrm{SNR}\, T_{sys}}{G\sqrt{...
2
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287
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How to convert between surface density in JY/beam*KM/S / arcsec2 to mass surface density in Solar masses / pc2
I am interested in studying the gas kinematics of atomic hydrogen (21cm line) for a galaxy and have output I'd like to convert after assuming a model for my data using BBarolo.
...
2
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31
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The electron–cyclotron maser emissions from Earth
The first-ever detection of radio signals caused by the electron–cyclotron maser mechanism outside of the Solar System, on Tau Bootis b was recently published (here). This phenomenon causes huge radio ...
2
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40
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When does oscillation of interplanetary plasma occurs?
When does oscillation of interplanetary plasma occur?
When and what are the reasons of the excitation of this plasma that makes it oscillate? Does it oscillate when is not excited?
Can extremely ...
1
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0
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46
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How to calculate a part of a spectrum from another part of it?
I have some radio data (flux) in 1.4 GHZ and also distance data. I calculated the luminosity for this frequency. Here, i want to use power-law and/or blackbody relation to calculate possible ...
1
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76
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How to superimpose an optical image upon a radio contour image using AIPS?
I am using AIPS by NRAO. I am trying to overlay a radio contour image with an optical image in the r-band. From the cookbook I could not find the suitable command for it. Both are fits files pf course....
1
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0
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48
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How can I determine the location of an object for one observer given the location for another?
I know an object exists at the location of the beam-pointing-center of a radio telescope. I know the elevation/azimuth of the beam pointing center, as well as it’s “location” in galactic coordinates. ...
0
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39
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How to calculate flux at a specific frequency from another frequency and spectral index
First of all, I know spectral index is $\alpha=\frac{log\frac{S_1}{S_2}}{log\frac{v_1}{v_2}}$ where $s$ are the flux densities and $v$ is the frequencies. I wonder that If i can use spectral index and ...
0
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70
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HI mass from HI column density
I have a galaxy for which I have HI column density values. I want to estimate the corresponding HI mass. To do the same, I want to estimate the flux density of this source. How can I achieve the same?
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