The traditional term in SF for the class of scientists that study and mess around with alien/ non terrestrial technologies is" Xeno"-biologists.
http://www.urbandictionary.com/define.php?term=xenobiologist
https://en.wikipedia.org/wiki/Xenobiology
Use Xeno as the prefix and then just tack on the specified scientist/ field.
What often happens is these scientists start in Xeno _____ then as they learn more about the aliens or technology, they default it to the closest field of human science.
So, if they discover say some sort of solar based weaponry or tech, they start with the Xenophysicist label, but as more is learned, and it is incorporated into human physics, they usually reclassify themselves or the tech into "Experimental" physics, or Fringe Science, but "Fringe" science is more a popular term than a scientific category.
Furthermore, there are different Classes of scientists, don't assume all scientists are white lab coated people in temperature controlled rooms, looking through microscopes, or those who just teach at universities.
Their are Research, Field, Experimental scientists.
The more important question is what is your purpose?
Are you trying to find a way of categorizing your research/ tech web?
Or are you just looking for the right term for the right kind of scientist?
Also, another note, not all researchers are scientists, but all scientists are researchers.
