Questions regarding the measurement of the amount of light coming from astronomical objects.
Questions tagged [photometry]
143 questions
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How do I calculate B-V to make a Hertzsprung Russell diagram?
I am reading my textbooks and a few "Astro101" websites, but I cannot find a final answer to this:
In the $B-V$ colour index that is plotted in an H-R diagram, are $B$ and $V$ the (observed) apparent magnitudes, or should they be corrected for…
Curious_George
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Acceptable errors in photometric measurements
As the title says, what is considered as an "acceptable" error in a photometric measurement (in magnitudes)?
I know that it will depend a bit on the final use of the data, i.e., the photometric error acceptable for a measurement meant to observe a…
David
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1 answer
Photometry systems
I know there's a difference between the ugriz and u'g'r'i'z' systems of photometric magnitude, but I also sometimes see UGRIZ written. Is there a difference between a UGRIZ magnitude and a ugriz magnitude?
I'm trying to apply the method from the…
Jim421616
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1 answer
How to collect photometric data for WW Aur
I have a problem with the collection of photometric data for star WW Aur. I can't find any file with HJD and mag column beside this one on Vizier.
I need more than one source of data. I will use the data to create a light curve via Scidavis…
Lenka Wudiová
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3 answers
Cubic spline interpolation in light curve of pulsating stars
Why is cubic spline interpolation used to analyze light curve of pulsating stars? Is there any scientific justification of such usages?
One example of using the cubic spline interpolation is here, section 4.
7_G.S.N
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Rest-frame magnitudes and fluxes
I have a question concerning rest-frame vs observed frame. In the observer frame, I can define an apparent magnitude and an absolute magnitude (as the apparent magnitude if the object were at d=10pc). From the apparent magnitude I can calculate the…
Benny
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on/off filter and their photometric calibration
I am reading a paper here
What is off band filter for? If we have already known the positions of the sources we are interested in, then off band filter is useless, correct? So an off band filter is to discovery sources?
An off band filter is…
questionhang
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