Use this tag for question related to X-rays which are a form of high energy electromagnetic radiation having wavelength ranging from 0.1 to 10 nanometres. Also referred to as Röntgen radiation after the scientist who discovered it. X-rays have a range of application including medical CT, airport security, astronomy, crystallography, etc. Different applications use different parts of the X-ray spectrum.
Questions tagged [x-rays]
377 questions
35
votes
5 answers
Do free-electron lasers actually lase?
Free-electron lasers are devices which use the motion of highly energetic electron beams to produce bright, coherent radiation in the x-ray regime. More specifically, they start with a high-energy electron beam and feed it into an undulator, which…
Emilio Pisanty
- 137,480
29
votes
2 answers
Why do X-rays go through things?
I always heard that the smaller the wavelength, the more interactions take place. The sky is blue because the blue light scatters. So why is this not true for X-rays, which go through objects so readily that we need often use lead to absorb it?
CognisMantis
- 684
29
votes
3 answers
How many X-rays does a light bulb emit?
I read somewhere that most things1 emits all kinds of radiation, just very few of some kinds. So that made me wondering whether there is a formula to calculate how many X-rays an 100W incandescent light bulb would emit, for example in photons per…
wythagoras
- 621
26
votes
6 answers
How can a black hole emit X-rays?
Considering that a black hole's gravity prevents light from escaping, how can a black hole emit X-rays? Visible light and X-rays are both electromagnetic radiation, shouldn't the black hole's gravity prevent X-rays from escaping?
hayalci
23
votes
3 answers
How would an X-ray scanner identify a mirror?
A mirror is under normal circumstance used to reflect Electromagnetic radiation also known as photons (light) and in airport security or medical facilities, they use X-rays to detect anomalies inside objects or bodies to detect narcotics or…
user43495
22
votes
5 answers
Why do X-ray telescopes have to be in space?
I have read this question:
For x-rays the (HUP limit) Δx becomes smaller than the distances between the lattice distances of atoms and molecules, and the photon will interact only if it meets them on its path, because most of the volume is empty of…
Árpád Szendrei
- 30,008
12
votes
3 answers
Why are there photographs of nuclear tests?
I was looking at old photographs of the nuclear tests on the bikini atoll. It dawned on me that you don't want to run film through airport x-rays, as it exposes the film. I've been told that a nuclear explosion emits all energy on the spectrum (IR…
Everett
- 351
11
votes
4 answers
Why we don't use gamma rays, x-rays or ultraviolet to transmit data?
The greater the frequency range of a transmission medium, the greater the number of bits per second it can transmit. In other words, the bigger the bandwidth in hertz available, the bigger the bandwidth in bits per second that can be…
user96769
- 123
10
votes
1 answer
Proton therapy in cancer treatment
Why are protons used in cancer therapy ? Is there any advantages compared to classics X-rays treatment or electron treatment ?
Cedric H.
- 4,856
9
votes
2 answers
Does the cavity magnetron in a microwave oven produce x-rays?
It seems like it should due to bremsstrahlung, since we're talking about electrons with 5-7KeV of energy slamming into the walls of the device, but I've found no information about this online, so I'm assuming something else must be happening.…
Joel
- 205
9
votes
2 answers
Is my tritium keychain emitting significant amounts of radiation?
I recently purchased a tritium keychain, composed of a small glass vial of tritium gas partially enclosed in a stainless steel fob. Here are the Amazon links so you can see a specific example:
Link for vial
Link for fob
The glass vial is 12mm long…
Dacromir
- 201
8
votes
3 answers
Where is the 2.05 MJ input energy measured? (referring to the recent experiment at the National Ignition Facility (NIF))
The recent fusion experiment at the National Ignition Facility delivered "2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output." But where exactly is the input energy measured?
My crude understanding is that the…
Roger Wood
- 2,423
- 8
- 21
8
votes
1 answer
Why is $K_{\alpha,3/2}$ always more intense than $K_{\alpha,1/2}$ in copper?
Consider characteristic X-ray emission from copper. The $K_{\alpha}$ line is a doublet because of the spin-orbit interaction.
But why is the $K_{\alpha,3/2}$ line always more intense than the $K_{\alpha,1/2}$?
Sørën
- 2,727
8
votes
5 answers
What is 2 $\theta$ in X-ray powder diffraction (XRD)?
Why are we taking 2$\theta$ instead of $\theta$ in X-ray powder diffraction (XRD). I have found the forum post 2 theta in X-ray Powder Diffraction (XRD), but there is no answer. What is the explanation?
Eka
- 1,057
7
votes
3 answers
What's the difference between Hard X-rays and Gamma-rays?
So I'm aware of this and this, but the question is Are Hard X-rays and Gamma-rays the same thing?
If not, then what would be the key difference between them. Moreover, How much would the properties of each type differ from each other?
I'd appreciate…
DarkLumiere
- 155