All Questions
4 questions
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How to use shift of H1 line to determine recessional velocity with 20m telescope?
I'm very new to astronomy, trying to find the recessional velocity of galaxies by finding how shifted the H1 line is. The galaxy I am using currently is NGC 7600, which is about 49 Mpc away and should ...
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How to convert between spectra given in terms of velocity (km/s) to wavelength spectra?
I have H alpha spectra of H II regions in our galaxy. In the paper, the x-axis is in units of km/s and the corresponding line width as well. From this, how can I get equivalent width of the H alpha ...
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1
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418
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How to isolate H$_\alpha$ from Nitrogen doublet emission lines
I am trying to find out line intensity and FWHM of H$_\alpha$6565 emission line from a quasar spectrum obtained from SDSS DR-14Q. Visual inspection of spectrum shows H$_\alpha$ being contaminated with ...
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1
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304
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Are hot stars like O-type stars entirely composed of helium?
Hot stars like O-type stars show no hydrogen in their spectra. Does this mean they are made entirely of helium?
Any explanation would be really helpful.
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