Questions tagged [spectroscopy]
Questions about the measurement of light waves whereby the wavelength is classified by its position in the electromagnetic spectrum.
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How to calculate the S/N of IFU or long-slit galaxy observations
I would like to calculate the Signal-to-Noise ratio (SNR) of long-slit or integral field unit (IFU) observations of H$\alpha$ emission. I can calculate the SNR or each individual spectrum, just fine. ...
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What (actually) does "peculiar periodic spectral modulations" refer to in this preprint?
I saw this ArXiv preprint after reading about it in the popular media.
I can not even understand the beginning of the introduction (much less the whole paper):
INTRODUCTION
A Fourier transform ...
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Why does Gaia use only calcium NIR lines for stellar radial velocity measurements?
I was reading this overview article about the Gaia spacecraft and I saw the following statement:
These spectra provide radial velocity information that are used to study the kinematic and dynamic ...
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Can all astronomical signals be considered Gaussian noise?
While studying the techniques astronomers use to mitigate radio frequency interference (RFI) I found it's often assumed that astronomical signals are (band-limited) Gaussian noise. Is this a ...
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Signal-to-noise in inverse angstrom for spectroscopy?
In a paper I came across the description of the signal-to-noise ratio (SNR) for observations with a spectograph. This was reported as $10\:1/\mathring{A}$. I am rather new to spectroscopy, so could ...
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How deep is the "A" Fraunhofer line in the solar spectrum? Is it from the Sun's or Earth's atmosphere?
Question: Where can I see - or even download - a fairly high resolution (~0.1 nm) solar spectrum at zero air mass - in other words from space without absorption and other features from the Earth's ...
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What is the temperature of the solar atmosphere (the corona) and how is it measured?
The temperature of the Sun's atmosphere, also referred to as the solar corona, is known to be hot even hotter than the Sun's surface. What is its temperature and how is it measured? How does it ...
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Is remote measurement of isotope ratios possible, or must a sample be aquired
Is it possible to measure to measure isotopic abundance of remote astronomical objects - ie measurement without having a sample to feed into a mass spectrometer? Do different isotopes show any ...
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Extraction of error spectrum in Sloan Digital Sky Survey
I need to know does SDSS spectrum contains error spectrum as well?
http://www.sdss.org/dr12/spectro/spectro_basics/#AbouttheSpectra
The above link says, further HDU's contain error spectrum and than ...
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Converting ångström spectral dimension to galaxy speed (km/s)
I have a spectral cube (in FITS format) whose spectral dimension is in ångströms. The sampling along the spectral dimension is 0.28A (CDELT=0.28). The observation in the cube is Ha emission of a ...
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How do astronomers distinguish the spectral lines?
As a black body a star emits a continuous spectrum of light and other radiation. I've learned they are capable of knowing of what elements the stars are made of because of the spectral lines. But how ...
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How can I convolve a template spectrum with a photometric filter response spectrum?
Suppose I have a template stellar population spectrum (say, from Bruzual & Charlot 2003) which runs from like 1000 Angstroms to 160,000 Angstroms and which has x-axis wavelength units of Angstroms ...
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How do I apply a velocity shift to a wavelength array with uniform logarithmic spacing?
Suppose I have a wavelength array for a spectrum in units of Angstroms. Suppose further that the wavelength has "uniform logarithmic spacing" such that if I just take the difference in Angstroms ...
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Which elements are an indication of habitable exoplanets?
Using spectroscopy the chemical composition of exoplanets atmosphere is determined. As a scientist, what spectral lines would you look for?
Which elements are relevant in pursue of a second earth?
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What is meant by ionization states?
I am going through the theory of Saha equation but I am not able to understand the concept of ionisation state? What are ionization states actually?
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