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Cookie
2013-Aug-03, 04:18 AM
Is it an actual word/scientific term, or am I destined to always lose the Alphabet Game?

SkepticJ
2013-Aug-03, 04:39 AM
Of course it's a real word. Yes, it is a scientific term. X-rays are photons that are more energetic than ultraviolet, and less than gamma rays. Of course these are human-created categories, the electromagnetic spectrum is a continuum with no natural divisions.

Solfe
2013-Aug-03, 06:01 AM
The word "X-ray" is a descriptor of action rather than a tight definition. Röntgen discover a ray came out of one of his devices, and rapidly worked out that it was a type of light and you could take pictures with it. But he didn't know all of the details, so he called it an "X-Ray". The X came from math: X = the unknown.

He never intended to invent a descriptor word or definition for his discovery, but darn it, everyone who spoke English liked "X-Rays". They liked it a lot. But many (or most?) people call them "Röntgen Rays", but not in English. It's a handy word for the stuff that allows you to take pictures of bone, but not terribly exacting. After the fact there is a definition of what an "X-Ray" is, but I find it confusing for a lot of reasons.

This is actually the part of science that kills me. Someone goes and mentions a historically figure and I replace formulas and processes with dates and names. It happens more than I'd care to admit.

Swift
2013-Aug-03, 02:05 PM
Yes it is a real word and yes, we are all doomed, though not by x-rays (in most likelihood).

I've done a fair amount of powder x-ray diffraction over the years, not to mention being the subject of various dental and chest x-rays.

swampyankee
2013-Aug-04, 03:05 AM
High-energy X-rays are good for inspecting things like welds.

Jeff Root
2013-Aug-06, 09:39 PM
Regarding what X-rays actually *are*, and how they are
distinguished from ultraviolet and gamma rays...

Ultraviolet light has poor penetrating power. It is strongly
absorbed by a wide range of materials, while most of those
same materials are relatively transparent to X-rays. X-rays
are typically emitted by electrons, while gamma rays are
often emitted from atomic nuclei. There is a great deal of
overlap at both ends of the X-ray portion of the spectrum,
so there are no dividing lines there, but I think those are
the characteristics which define the distinctions.

-- Jeff, in Minneapolis

Buttercup
2013-Aug-06, 10:51 PM
Well, we know that they come before Y-Rays. :)

John Mendenhall
2013-Aug-07, 01:35 AM
Yes, but after zee injury.

Cougar
2013-Aug-09, 05:04 PM
Is it an actual word/scientific term, or am I destined to always lose the Alphabet Game?

There are three types of compounds: Those written as single words, with no hyphenation, are called closed compounds--the word "flowerpot," for example. Hyphenated compounds, such as "merry-go-round" and "well-being," are the second type. Those in the third group, called open compounds, are written as separate words--the nouns "school bus" and "decision making," for example. - source (http://www.getitwriteonline.com/archive/042703compwdshyph.htm)


It's a hyphenated compound word. I'm not sure what the rules of Scrabble say about those....

Trebuchet
2013-Aug-09, 05:47 PM
Yes, but after zee injury.

I've got two whole CD's full of my Xrays that you really don't want to see.

Jeff Root
2013-Aug-09, 08:05 PM
Cougar,

Between the time that I opened this page a few minutes
ago and the time that I got to your new post, the question
you addressed occurred to me, too, and I looked it up. My
standard English dictionary uses no hyphen (for the noun),
while my Radio Shack dictionary of electronics does use a
hyphen. Complete non-agreement.

-- Jeff, in Minneapolis

Delvo
2013-Aug-14, 02:39 AM
X-rays
are typically emitted by electrons, while gamma rays are
often emitted from atomic nuclei. There is a great deal of
overlap at both ends of the X-ray portion of the spectrum,
so there are no dividing lines there, but I think those are
the characteristics which define the distinctions.I don't recall anything like this at the X/UV boundary, but you don't even need the caution words "typically" and "often" for the X/Γ boundary. What you described is the difference there, by definition. The wavelength ranges for X and Γ overlap, but within that overlap where both kinds of sources are capable of emitting the same wavelengths, to paraphrase one of my professors, "We call it an X if it came from an electron and a Γ if it came from a nucleus". (This was from one of my classes on the way to becoming certified in the diagnostic use of X-rays, although I still don't have a job from that yet.)

I also found it interesting that Γ, X, and UV together are called "ionizing", which makes visible light the highest energy level that's not ionizing. Some other species can see a bit higher than what we can, but not by much. There's probably a reason why visible range stops there... sort of like the fact that there's a reason why the other end of visible range normally (except for some cold-blooded animals that hunt warm-blooded ones) stops just above the point at which everything in the Earth's surface's usual temperature range would seem to glow...

Cookie
2013-Aug-14, 02:11 PM
Thanks for all of the info, and jokes. We did a do-over, and I came in second place.
I could use X-Ray, in the first round, but I ran outta words that start with "xeno", in subsequent rounds.

Woulda been nice to get 1'st place, but it sure beats a disqualification. ;)

Jeff Root
2013-Aug-16, 01:43 AM
X-rays are typically emitted by electrons, while gamma
rays are often emitted from atomic nuclei. There is a
great deal of overlap at both ends of the X-ray portion
of the spectrum, so there are no dividing lines there,
but I think those are the characteristics which define
the distinctions.
I don't recall anything like this at the X/UV boundary,
but you don't even need the caution words "typically"
and "often" for the X/Γ boundary. What you described
is the difference there, by definition. The wavelength
ranges for X and Γ overlap, but within that overlap
where both kinds of sources are capable of emitting
the same wavelengths, to paraphrase one of my
professors, "We call it an X if it came from an electron
and a Γ if it came from a nucleus". (This was from one
of my classes on the way to becoming certified in the
diagnostic use of X-rays, although I still don't have a
job from that yet.)
I knew that radiation in a range of wavelengths is
called "X" if it came from an electron and "gamma"
if it came from a nucleus. What do you call it if you
don't know the source? X-rays are typically but not
always emitted by electrons, while gamma rays are
often but not always emitted from atomic nuclei.



I also found it interesting that Γ, X, and UV together
are called "ionizing", which makes visible light the
highest energy level that's not ionizing.
The term "ionizing" generally means "capable of
completely removing an electron from an atom or
molecule. However, it isn't necessary to completely
remove an electron in order for there to be an effect
of the radiation on the atom's or molecule's chemistry.
Radiation of a frequency too low to provide enough
energy to completely remove an electron can still raise
an electron to a higher energy level.

Also, even if one photon of a particular frequency
doesn't have enough energy to ionize an atom or
molecule, two or three photons of that same frequency
might have enough energy. The first photon raises
the energy level of an electron, and the second photon
kicks the excited electron out of the atom or molecule.

So visible light and even the shorter wavelengths of
infrared can be somewhat ionizing. Effects of visible
light on our eyes let us see. That is due to electrons
being pushed around by photons.

-- Jeff, in Minneapolis