X-ray Definition and 309 Threads

today I took a x ray for my lower back, now medical issues aside what I want to know is is there any estimate of the dose I received? just to be clear i don't have paranoia and I know basic physics so I'm not scared but purely out of curiosity because later this year I might have to do things...

A recent post here made me think about this so I wanted to ask. Now a x ray tube working principle is basically the opposite of the photoelectric effect, here instead of photons electrons strike a metal target to deposit their energy which is released as heat (IR radiation) and photons. So the...

Just has my first CT scan ever for low dose cardiac scoring. Held my breath twice with gantry in fixed position and then once again with gantry spinning. I thought I would have heard the high pitched x-ray when beam energized but didn't at all. All I heard was normal fans and the mechanicals of...

Here is what I understand so far about x-ray energy transitions within an atom: The shells are divided up from lowest to highest as K, L, M, N, O, and so on. The X-ray associated with an electron dropping to a K shell is called K radiation. If the electron drops dropped from a shell directly...

Hey, Theory: The voltage of a thundercloud is too low to ionize air particles and to produce a thunder. Particles of cosmic radiation are the trigger. I calculated whether the voltage of a thundercloud is enough to ionize air particles but the voltage was always to low. So I wanted to know...

Hi all, I'm wondering how, for each peak in an x-ray spectra from a material (and using a crystal analyser), it is determined which energy level jump the peak corresponds to? How would you figure out the correct value of n to substitute into Bragg's Law to find the energy of the beam? Thank you!

Question: Explain the rules of reflection for different cubic lattices (SC, BCC, FCC) based on the Bragg ́s law. Help: If we have incident of X-rays, which planes have constructive/ distractive reflection? Why? Please calculate it for the following crystal planes. 001, 011, 111, 200, 210, 211...

What types of light are able to pass through the human body without causing damage to tissue or individual cells? Are there any truly safe alternatives to x-rays that could allow doctors to see internal body parts but not cause damage from extended exposure?

For x-day diffraction maxima we have braggs law 2d*sinθ = mλ (maxima) Is there an analogous law for the minima like 2d*sinθ = (m+1/2)λ (minima?) Thanks!

Homework Statement A research worker is irradiating some drug samples in an x–ray beam. The tube is running at 60kVp with a tube current of 4mA. Although the ‘shutter open’ lamp is extinguished, indicating the shutter is closed , it is faulty and the researcher loads his samples with the...

Hey guys, I am currently running an experiment with Cs-137 multiple sources ranging from 1 to 10 uCi, i have a lead pig with a Cs-137 source at the top and a 1/4" small tunnel drilled through the 2" thick slab inside the pig is the Gieger counter, Using various heavy metals as a shield i seem to...

Homework Statement Homework EquationsThe Attempt at a Solution I would say that the wavelength of the characteristic spectrum will increase, but what about the bremsstrahlung spectrum? Will the cutoff wavelength will be longer?

Does anyone knows where I could find the answer to the problems in the classical book on x ray Diffraction by B. E. Warren "X-ray Diffraction" ? It's not an easy-to-read book so I think that checking my solutions to the problems would be really helpful. thanks

Hello What does it mean when people say high resolution xray diffraction? What is the difference between regular Xray diffraction and high resolution X-ray diffraction? Thank you

Homework Statement The X-ray intensity distribution function for an X-ray lamp is given on the figure. What is the maximum velocity of the electrons? What is the potential difference under which the lamp is operating? Figure: http://imgur.com/01kCBc8 Homework Equations Kmax = 0.5m(vmax)^2...

X-ray has enough energy to eject the electron in the atom, molecule etc. But in the x-ray diffraction electron does not eject, only oscillate with the same frequency as X -ray,why? Why does not x-ray eject the electron?

Homework Statement [/B] In my excercise book, I was given a typical diagram as that in Fig (6-7) above. And the problem statement says: The diagram presents the x-ray spectrum produced by Coolidge tube. Determine the least potential difference needed to produce the characteristic radiation...

This question is as dumb and simple as it can be: Why is the path difference 2dsinθ? Or better said: Why x-ray scatters like in the image? (Couldn't there be another scattering angle for both atoms other than θ?)

I am a lay person, so the physics lesson would only confuse me. I do reloading of ammunition for competitive shooting (Cowboy Action Shooting). I have someone offering to sell lead for melting and casting bullets. He has indicated its source was shielding from hospitals used in X-ray shielding...

Hi everyone! I'm starting to work with a mini X-ray tube provided by Amptek. I want to use it to calculate the efficiency of a detector I'm going to use latter, so knowing the total flux the tube emmits and measuring the flux the detector receives, that should be enough (both data normalized to...

That pesky 3.5 keV line just won't go away. The authors note that it's compatible with dark matter composed of 7.02 keV sterile neutrinos. If such is the case, the Majorana mass scale of the seesaw mechanism needn't coincide with the GUT scale (if such a scale even exists).

Hi,I've been doing a lab cycle on X-ray crystallography. We are using Cu X-ray source on chloride salt crystals. It seems that the Bragg peak profile are commonly acknowledged to be a Voigt function, which is a convolution of Gaussian and Lorentzian. I am wondering what's the physical reason for...

Homework Statement The Spacing between the Na and Cl atoms in table salt (NaCl) is ##d=2.82x10^{-10}m##, which was first deduced from Bragg scattering. For an experiment where X-rays of energy 20 eV are produced, what are the corresponding Bragg angles below ##90^{\circ}## for scattering from a...

Hi, The x-ray consists of the bremsstrahlung spectrum and the characteristic spectrum. We can get x-rays by using Coolidge tube where there are an applied voltage on the tube between the filament and the target. The bremsstrahlung is depeding on the PD between the filament and the target, but it...

Homework Statement I have done a simple lab experiment to find the lattice constant for NaCl. Using a diffractometer, radioactive counts were measured as a function of crystal orientation angle for electron voltages of 20 and 30 kV. The average lattice constant found wasclose to the accepted...

Hi, I was studying Roentgen (and Crookes tubes) and realized that they used spark gap generators which sent out bursts of AC current. However, Crookes tubes work with one end being the cathode and one the anode. They did this before diodes so how did they ensure that one side was negative and...

I'm a bit new to studying physics so I hope this question doesn't sound off. I already know this "Photons are emitted from an atom when an electron transitions from one state to a lower-energy state. The energy of the emitted photon equal to the difference in energy between the two states."...

In X-ray diffraction, during the experiment a X-ray beam will create an incident and diffracted beam, but what exactly is the virtual source? I may be mistaken but isn't the source the incident beam, in the attached image, it seems to suggest otherwise?

I am a high school student, so I know only the basics of X-Rays.I simply know about continuous X-rays, cutoff wavelength and threshold wavelength. Now if I increase the potential applied to the X-ray tube, I am certain that the minimum wavelength of emitted radiation decreases. (I say this using...

China launched five small satellites Thursday, including the X-ray Pulsar Navigation satellite that eventually could help spacecraft headed for deep space navigate, the latest piece of China’s ambitious space program, NASA Spaceflight.com reported. The X-ray pulsar, developed by Aerospace...

1. Must the electron brought to rest(in one step or many steps) in Bremsstrahlung effect? 2. Besides from a coming electron knocking off an electron on the shell then another electron fills the void, can the coming electron just excite an electron on the shell to a higher state and release a...

Homework Statement Although not a computational problem, I still have difficulties understanding emission of characteristic X-rays. Can someone please clear up my confusions about the topic? Here's where I'm stuck, with two texts as an example: Source for the above...

If you have chest x-ray of the lungs.. how much of the x-ray radiation goes to other parts of the body (like the lower abdomen)? Or do the machines just focus the beam on the chest?

Hallo everyone, I have a question about X-Ray shielding in a scanning electron microscope and I hope you can help me! The topic is that when electrons hit the specimen, characteristic radiation up to 10keV is generated. This radiation is blocked/decelerated my the surrounding tower and chamber...

So, I was thinking about building a low power klystron (around 5W.) I know this involves making an electron gun and electron guns can emit x-rays. I have a few questions: 1. Will 5W produce x-rays? 2. If so, what is a safe dosage of x-rays? 3. How can I shield myself and others from the...

Hello, I'd like to know which book or papers I'd read to understand, possibly without too rigorous mathematics knowledge, how do photons like X-rays or gamma ones reflect off surfaces and attenuate through solids or generally speaking, facts about how do they interact with the real world. So...

Homework Statement An x-ray tube with a stationary target is operated with a constant voltage and current of 100kV and 50mA for 0.2s . Approximately how much energy will be deposited as heat in the target and how much emitted as x-rays? Homework Equations ##P=IV## ?The Attempt at a Solution...

Hello, I need to learn how Solid State NMR and X-ray Crystallography work (theory and practical application). I'm primary interested in how those experimental techniques are used to determine molecular structures. I'm an undergrad physics student and I need this to pass my final exam. So if some...

Hi all, In an x-ray spectrum, the curve part represents the bremsstrahlung part, and the spikes are the characteristics x-rays. Characteristic x-rays represent a discrete energy. However, in many textbooks, I noticed that the characteristic x-rays are often represented as a peak, which implies...

Good morning all, I was just wondering the following question. When an electron is accelerated it emits electromagnetic radiation, depending on how much it is accelerated the energy varies so the frecuency does and the electromagnetic wave emitted would be of different colors or maybe even...

When the cathode emits electrons which are accelerated towards the grid, usually on its way it will ionise a molecule in the vacuum. However at a certain low pressure there are too few molecules and therefore the electron will hit the grid and emit an x-ray. My question is, wouldn't electrons...

Good afternoon, I'm doing a research on x-rays machines. I chose the model KL27-0.8-70 (or any oral x-ray machine). I would be very grateful if someone could provide me some technical information as the radiation pattern, the aceleration efectuated on the electrons, and the electric field...

Homework Statement (The question is in the image attached) (c) An X-ray unit in the cardiac catheter labs has an output of 80µGy/mAs at 1 meter when the unit is set at 100 kVp. After adding 0.3mm Cu to the beam the photon intensity is reduced to a quarter and tends to vary in proportion to...

This should be easy but I'm totally stuck here. So I'm calculating the Kβ line (emitted energy) of Molybdenum (Mo 42). I'm using Moseley's law and am moving from the M-shell to the K-shell. Recall Moseley's law is E = 13.6 eV (Z-σ)2 *1/n2. The effective formula for the energy emitted is thus...

In mammography, an Mo anode is used because it produces characteristic X-rays at about 17-20 keV. Apparently, the ideal filter is also Mo. Why is this? Surely all the x-rays would just be re-absorbed by the filter? Thank you

I got question in exam, 1) How to control hardness of X-ray? 2) why low frequency of x-ray is used for investigating tissue?? so in 1) what does controlling hardness means?? and in 2) can't we use high frequency of X-ray ?so that it will penetrate more as tissue are poor absorber...

Unfortunatley I cannot post this question in the Homework section (not sure why) so I hope its OK if I post here and show work as appropriate < Mentor Note -- thread moved to HH from the technical physics forums, so no HH Template is shown > QUESTRION State two design features in an X-ray tube...

Hello, I am trying to create peak models for some XPS spectra. I have a decent intuition of the chemistry of the samples, and I obtain really good residual standard deviation values for the modeled data; however, some of the FWHM of the modeled oxidized species (C and P) on the narrow scans are...

I recently got an older tube amplifier , since ti was dirty from being left for a long time in an old shed i took the covers off and cleaned it , now I am listening it also with the covers off , everything works etc. Now I wonder do tubes at lower voltages and lower frequencies such as in the...

Homework Statement (1) An ideal digital detector only suffers from quantum noise. If, after being exposed to 5 µGy the mean pixel value in the image is 100 and the standard deviation of the pixel values in the image is 5, calculate the SNR? The relationship between pixel value and detector...