# Tagged Questions

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1answer
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### Synthetic Photometry - Calculating a colour index

I have a theoretical black body spectrum, described by plancks law. I also ave the bandpass sensitivity function for various filters. I would like to calculate a colour index from this information, so ...
0answers
59 views

### need data-point: count rate of APD (avalanche photo-diode) for specific aperture and stellar magnitude

I hope lab / experimental physics is fair game for this web-site. If not, sorry! I'm designing a sensor system to perform specialized [astronomy and space-sciences] experiments, and need a "reality ...
0answers
15 views

### Stretch Factor for SNIa

How do I compute the stretch factor for a Supernova Ia ? Data I have : Redshift, Points on the light curve, Rise time (∆m=2), Fall time (∆m=2), Time from the peak day for an inflection point in the ...
0answers
33 views

### Is it possible to have a 1m2 base at 1m from a source with an angle of 1sr?

Theoretically, a light source with a solid angle and $1\ \mathrm{candela}$ will produce $1\ \mathrm{ lux}$ at a $1\ \mathrm{m^2}$ area $1\ \mathrm{m}$ away. However, when I calculate the base of the ...
0answers
61 views

### Does Lambert's formula give correct results of luminous flux density?

A uniform point-source S, having luminous intensity, $I$, is located at a point at a distance $r(=OS)$ from the center O of a plane having area $A$ such that $\theta$ is the angle between the line ...