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Synchrotron Radiation - Science method

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Hello all, which software can be used to export the standard XRD spectra of titanium alloy under different X-ray wavelength? How to operate? Such as 0.11 angstrom or 0.6887 angstrom (These X-ray wavelengths are generated by Synchrotron radiation XRD)
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Dear all,
I recently have difficulty in processing the synchrotron radiation (λ=0.6887 nm) XRD data by Jade 6. I’m looking forward to some kind advices.
My samples are Ti-55531 alloys. The “.chi” files have been converted to “.txt” and “.mdi” ones which are compatible with Jade 6. At this stage, I am able to open the files in Jade 6, switch the target option from “Cu” to “US” on the top left corner, and input 0.6887, as shown in Fig. 1.
After clicking OK, I retrieved Ti as the only possible element and added the standard pattern of “Ti, PDF#44-1288, Im-3m (229)” into my XRD pattern. As shown in Fig. 2, huge peak difference is observed between standard PDF card (vertical lines in yellow) and the experimental results.
Could you please help me with this issue in analyzing synchrotron XRD results in Jade 6? Your kindness will be highly appreciated!
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Dear Gerhard Martens Shi Huang , thanks a lot for your kind suggestions. I will double check the diffractometer and also give a try with Jade 6.0 with different wavelength attempts.
Will update if any progress is gained.
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Hello all!
I am just wondering if someone can direct me to equations and processes for Seeded FELs? Something general, not necessarily XFELs.
I am aware of the undulator equations etc, etc - but how does that all change/get affected by an external laser trying to create microbunches?
Any assistance would be greatly appreciated as I'm stuck, and I've bothered certain individuals a bit too much (so I'd prefer to leave them alone)...
Edit: Any and all equations would be helpful (i.e. gain length, expected output power, expected output harmonics, etc)
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By the way, contact me in case you have difficulties in getting the text.
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We collected the spectral maps of the soil. The aperture size of map was 10 μm. The map profiles of aliphatic compounds, carboxylic acids, protein, lignin, polysaccharides, and iron oxides (Fe-O) were created with peak heights at 2920, 1716, 1653, 1513, 1035, and 690 cm-1, respectively. We performed a correlation analysis in iron oxides and the organic compounds. The correlation coefficients (R2) of Fe-O with the organic compounds reflects the spatial distribution of organic compounds with iron oxides.
I want to know whether the slope values of organic compounds and Fe-O can represent the relative contents of organic components in the measured regions of SR-FTIR?
Combined analysis the correlation coefficients and slope values, if we can obtain the relative contents of organic components, which was associated with iron oxides? Not the values, but the large or little
我们采集了土壤样品的同步辐射红外图谱。提取了其中不同有机官能团和铁氧化物的光谱信息。我们将每一个有机官能团的光谱都和铁氧化物的光谱强度进行统计分析。相关系数反映各有机官能团与铁分布之间的空间相关性。我想知道的是有机物与铁之间的斜率大小能否反映扫描区域各有机物质的相对含量?其次是结合斜率和相关系数的大小,是否能得到铁氧化物上结合的有机物质的相对含量(哪个多哪个少)?
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Can you give me your e-MAIL, I will sent you my spectrum.
Thank you!
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Can you please explain with reference of experimental data?
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The depth scale of XPS measurements is controlled by the electron inelastic mean free path, which is dependent on the kinetic energy. The higher the kinetic energy of photoelectrons, the further they can travel before undergoing scattering, and so the sampling depth increases (we define the sampling depth as 3 times the inelastic mean free path). The kinetic energy of core level photoelectrons can be controlled by varying the X-ray photon energy as is available at synchrotron radiation sources. So to go from surface sensitivity towards more bulk sensitivity (i.e. to increase the sampling depth of XPS) you increase the kinetic energy of core level photoelectrons by increasing the photon energy. An example from our group depth-probing through nanoparticles is here: http://pubs.rsc.org/en/content/articlepdf/2017/NR/C7NR00672A
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The case: quasar 3C 273 at 15-24-43 GHz. Faraday rotation measure at ~1 mas from the core changes its value from +3000 rad/m^2 to -3000 rad/m^2 in 3 month. EVPA depends linearly on lambda squared, fits are ok. 
Any ideas on how can the RM change so swiftly?
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A change in sign can only be caused by a change in direction in the line-of-sight magnetic field component at that location. Has the morphology of the jet changed much?
Also given that you only have 3 frequencies it may be also useful to check for any n*pi ambiguities in the chi versus lambda^2 fits which may cause the RM's to vary.
It may be also useful to check the intrinsic polarization angle derived from the RM fits. Check if this changes much over time. The angles should be aligned perpendicular or parallel to the jet in most cases. If the angle varly wildly around the jet it may be a sign of an*pi ambiguities in the fits.
That the best answer I can come up with so far. If I think of something else I'll let you know.
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Is there a way to obtain minimum synchrotron radiation without increasing the radius of the path.Also does the mass of the particle play any role in the amount of radiation emitted?
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No, I dont know any realistic modus. The usaual formular for the transversal emitted power is proportinal to E**4 /(m**4xR**2). Have a look in the chapter 11 of one of my textbooks.
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Are there investigations about heating of the pattern by synchrotron radiation?
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Thank you. But phenomenologically I would like to understand: Is it possible to use the synchrotron heating as to analogous of laser CVD for metals deposition from carbonyls (350-420 K)? For example, it will be nice for NEMS production, due to high brilliance and good emittance (not LIGA-method).
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I need to some brief information about synchrotron radiation and the features of x ray which is produced in comparison with the x ray produced in x-tube
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Dear Sankaran,
synchrotrons are large scale facilities - the european synchrotron source ESRF in Grenoble, France, has a circumfence of almost 1 km! They are thus not portable - an not even table top machines. In fact, there are important safety issues, you have to shield the storage ring, the beamlines, the optics, ... with huge amounts of concrete and lead, and you have to secure the related areas so that noone may enter during operation. For different experiments, you apply different detectors for the X-rays (or the electromagnetic radiation in general), ranging from the infrared to several 100 keV.
Alterations of the samples are very likely, depending on the material, the incident energy and its intensity, radiation damage may occur, and even a complete destruction of the samples may happen, especially if not cooled, either with water or even with liquid nitrogen ...
In any case, we regularly do excursions with students and also with pupils from school to show them the exciting environment in which we are allowed to work!
So there are a lot of aspects that need to be considered! Cheers, Dirk
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If so, what would be the power dissipated from a single point mass rotating about an external axis?
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I did not answer the original question, as I have little understanding of, and rather less trust in, GEM. However, since it is a theory very much formally akin to EM, I would assume that you question would be answered by the formulae of synchrotron radiation.
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I have some colloidal samples difficult to dry and I am looking for other possibilities to study the structure of these samples.
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x ray diffraction or small angle xray scattering can certainly be done using synchrotron radiation to measure colloids.
As synchrotron sources develop and are able to provide higher coherence, other techniques also become possible such as ptychography for imaging and XPCS for studying colloid dynamics.
The following papers (amongst many others) might be helpful/interesting:
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I have single crystal X-ray diffraction data collected with synchrotron radiation (wavelength 0.6631 Å ). I would like to know if there is a method to estimate the contribution of Compton scattering to the total diffracted intensity per solid angle .
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FYI, in Google images googling for "photoelectric effect compton scattering pair production" brings up many versions where the three effects are compared in a two-dimensional plot, with the photon energy horizontal and the atomic number vertical. Before these existed so conveniently on the web, I had made just such a plot in a paper from the mid-1980s.
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As, i am new in this feild, I want to know how can i use fricke dosimetry to determine the x ray from synchrotron radiation
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Fricke dosimetery may not be ideal for determining the X ray measurement from a synchrotron.  Synchrotron radiation is broad band and ranges form the visible through the X-ray spectrum.  Measurement of the change of Ferrous to ferric ion in a solution may not be the best way a the reaction is likely to be very energy dependent, nevertheless it could be done, but you would need to calibrate it against a standard by measuring the ionisation in air, produced by the beam and then calibrating against the F++ to F+++ reaction rate. 
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Framework Grant Röntgen-Ångström Cluster
The Röntgen-Ångström Cluster (RÅC) is a Swedish-German research collaboration within structural biology and material sciences. The aim of the grant is to strengthen research in materials science and structural biology that uses neutron and/or synchrotron radiation and to stimulate the use and/or development of expertise in large-scale research infrastructures currently available or being planned in the area.
The Swedish Research Councils’ framework grant aims to give researchers the opportunity to do research with significant scope and depth. Framework grants can give strong research groups the freedom to act within relatively generous frameworks regarding funding and choice of research orientation. The Swedish Research Council supports basic research of high quality in all scientific disciplines and promotes research cooperation and exchanges of experiences.
More information can be found here:
If interested, please contact me by sheng.guo at chalmers.se. Note the deadline for application is 2015-06-03
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Please follow the link given to find more information.
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What is the measure of the spatial resolution in reconstructed image if single far-field Bragg peak is used?
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Definitely interested in learning this one! Thanks for asking Dmitry!
BTW you could increase the "TOPICS" up top to as many as 15. Find topics with the most "Followers" to get the maximum exposure to your question. This will beget you maximum participation by the "experts" in the RG community.
As of 02-14-15 0652 EST: Views 32; Followers 5; Answers 3
I'll share this among my Network as well, both RG & LinkedIn. Let us then monitor stats.
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  1. Synchrotron radiation
  2. XANES and XEOL
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Dear Yuting, X-ray absorption spectroscopy is generally associated with the creation of a photoelectron, that can be treated as an electron wave propagating through a sample, and the interaction of this photoelectron wave with neighboring atoms modifies the absorption probabilty if the energy of the incident radiation is varied in the vicinity of an absorption edge. You may in many cases directly measure this absorption coefficient by means of a transmission more experiment, however, in several situations you may not penetrate your sample and measure the transmitted intensity., for example in the case of a bulk material sample or if you are working with very low energies, for which the attenuation length in solids is very small (in the order of some 100 nm, see e.g. http://henke.lbl.gov/optical_constants/atten2.html).
In those cases, you may use different other signals, that are closely related to the absorption coefficient. For example, the X-ray fluorescence, i.e. the number of excited characteristic X-ray photons of a considered transition of an element. The fluorescence originates from the relaxation of the created core hole, and its intensity is proportional to the number of core hole, and thereby to the absorption coefficient.
Other signals are the absorbed current, the X-ray excited luminescence, the total electron yield, ... - all these quantities are directly linked to the photoabsorption process itself!
Differences in PL and FL may originate from the fact that the fluorescence is usually not site-selective, while the XEOL is, which has implifications especially for magnetic materials, or complex crystallographic structures, where different optical transitions are representative for specific sites in the crystal lattice.
For the XEOL, check the following article published in
EXAFS and Near Edge Structure III, Springer Proceedings in Physics Volume 2, 1984, pp 490-495 by J. Goulon et al.,
"X-Ray Excited Optical Luminescence (XEOL): Potentiality and Limitations for the Detection of XANES/EXAFS Excitation Spectra"
If you compare fluorescence and 
Hope this short explanation helps, Dirk
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Has anyone worked on nanoparticles using either X-ray absorption near edge structure (XANES) or Synchrotron radiation? I would appreciate an enlightenment on better techniques out of the two to examine biotransformation/speciation of nanoparticles in plant parts after uptake.
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Mercuric nitrate monohydrate can easily take water from air, so is it really difficult to obtain a uniform layer of salt.
I know that people can prepare Hg sorbed on goethite from Hg(NO3)2 solution. However, I was having hard time to find reference materials that were made of Hg(NO3)2. I was wondering if I need to make Hg(NO3)2 reference material, should I consider to let Hg(NO3)2 precipitate from solution instead of directly using salt?
Thank you very much  
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Hg(NO3)2.H2O can readily be bought from chemical suppliers such as Alfa Aesar relatively inexpensively. Mixing with a diluant such as BN, Alumina, Silica or  cellulose should provide best results. A glove box or glove bag could be used in you have issues with water uptake. As mentioned above Kapton tape will seal the sample for measurement.
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Can any one explain physically why the refractive index for x-rays is less than one? Mathematically in many books it has been explained using the Lorentz oscillator model, but can some one explain it physically?
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Sorry, folks, but the three comments (by Wasim, Marek, Manohar) all touch on the topic, but none are the answer (I think). Wasim describes a nonlinear behavior of the oscillating electrons in the material that are also mentioned, more correctly in my opinion, by Manohar: the oscillating electrons (in the classical approximation, considering electrons as infinitely small points of charge) achieve the same frequency   as the electromagnetic wave that sets them in motion. They then radiate their own waves, and these combine with the incoming wave. The phase between the incoming and the induced wave determines what the index of refraction is.
If the incoming wave oscillates relatively slowly, the electrons can follow the wave: they are in phase. So, what is 'relatively slowly'? This is in relation to the oscillation frequency of the electrons themselves: in this picture the electrons may be bound to some equilibrium position and oscillate back and forth around this location, always with a small enough amplitude that nonlinear effects can be ignored. Now, when the incoming wave's frequency exceeds that of the electrons, the electrons can no longer follow the wave, and they get out of phase. Then, the waves radiated by the electrons are out of phase too, and the index of refraction is less than unity.  
What Marek says is true, but not an explanation, it's a description. Mine is also a description but it describes the mathematics that models the underlying physics, in the classical approximation.
Interestingly, you can make lenses for x-rays with this refractive effect: they have been used on synchrotron radiation sources since 1996. In some ways the best material for these lenses is lithium metal, because for many interesting x-rays this material is little more than a bag of otherwise free electrons: one problem is that an electron bound to some equilibrium location can get into some higher energy state when you take quantum mechanics into account, and when it does the electron takes the necessary energy from the wave which is then absorbed. Not good, for a lens. 
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Randall’s plaques are soft tissue calcifications found in the deep renal medulla skirting the surface of the epithelium of the papilla, where they act as nucleating elements for renal calculi or stones. These plaques have been described until now as composed of carbapatite (poorly crystallized carbonated calcium phosphate or carbonated apatite, abbreviated to CA). Characterization of these plaques in real environments has led to more surprising results.
A group consisting of physicists from the Laboratoire de Physique des Solides and the DIFFABS beamline at SOLEIL, in collaboration with doctors at the Necker Hospital, have carried out for the first time the characterization of a Randall plaque positioned on its renal papilla. More precisely, they carried out X-ray absorption spectroscopy experiments at the Ca K-edge on DIFFABS.
These researchers were able to study the exact nature and proportions of the mineral phases present in the Randall plaque when moving from the top of the papilla towards the deep medulla without the need for preparation protocols that might alter the sample’s physicochemical state. They then showed that the absorption spectra obtained looked more like that of amorphous carbonated calcium phosphate (ACCP) than that of CA, therefore revealing that Randall plaques could be composed mainly of ACCP and not of CA.
This result, in apparent contradiction to that stated in published literature, is easily explained if one takes into account the fact that the level of water in the sample governs the transition between ACCP and CA, of which it is the precursor. In earlier studies, the samples were dehydrated, which could have modified the phase transition from ACCP to CA, whereas, in these experiments, the water levels were maintained; the Randall plaque could then be characterized while keeping its physicochemistry intact.
It should be noted that ACCP is evidence of an oversaturation in calcium phosphate by an excess of calcium and/or phosphate and/or due to too high a pH. Its presence in increasingly young subjects raises the question: does nutrient-enriched food specially aimed at young children affect the physiology of the kidney?
The debate is open.
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By reading the content, I do agree that the nutrient enriched diet certainly affects the function of the kidney, but the children group as said, needs it more than the adults. Now as far as the increased chances of formation of renal calculi are concerned due to the richness of calcified nutrients, skilled management of its removal should be done as done in case of adults. As they are advised to take ample of water to avoid the formation of calculi, the children diet should also involve cleansing nutrients like fibres and then plenty of water should be administered in their diet.
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By knowing the spectrum of radiation one is able to simulate imaging or dose related problems in medical cases.
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No: MCNP doesn't do radiation from electrons accelerating in a magnetic field.
But, why would you want to in the first place? You have an analytical expression (in the x-ray data book (xdb.lbl.gov) and its sources. But, you can put in the synchrotron spectrum, and get the dose and stuff like that out.
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I am looking for an article that is very much exciting, relating to synchrotron radiation and its techniques.
For a presentation that is to be performed soon, there are so many to choose from.
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I do not know what you are really interested in, but in addition to the proposals made above, I would focus on experiments and techniques, that can hardly be done with conventional laboratory equipment, making use of the unique properties of SR. So for example EXAFS uses the continuous spectrum, pump probe experiments use the special time structure, magentic measurements use the polarization properties, single micro- (or nano-) particles can be investigated making use of the excellent focussing properties of SR, etc etc. So I would select some experiments, and highlight why this can only be done with SR. Good luck, Dirk
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Seeking to understand the mechanism of how x-ray generated in synchrotron is circularly polarized before it comes out of a beamline.
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The electric field of the radiation emitted by a charged particle will always be an image of the path that the charge followed, so any field which causes an elliptical trajectory will produce elliptically polarized light. APPLE devices are very popular in synchrotrons, but by no means the only method.
It is also possible to collect elliptically polarized radiation if the observation point is not in the same plane as the acceleration, such as from being vertically offset from the plane of a bending magnet. See the X-Ray Data Handbook Section 2 for more information. Or I can send you other more detailed references if you are very keen.
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We know that accelerating charges radiate. What if the charge was static in some reference frame and the observer was the one who accelerates with respect to that frame? Is there any relation to Unruh radiation?
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Mozafar,
(1) You are partly correct in saying that the field and the charge are different entities. Well they look like being different, actually they are not. When the charge does radiate, it does not radiate away all of its field and become bare ! Part of Its field remains intact as well. Next, as an aside, even if a photon gets radiated from the accelerated charge, it remains entangled with it all along, and this entanglement is an experimentally observed fact.
(2) You cannot kick the electron without first kicking its surrounding EM field. In fact ,the same QFT as well as CFT tell us that the kicking (interaction with the electron) can occur only through the field. No direct kicking of a bare electron is possible, and there is no bare electron available either.
(3) The above applies to the freely-falling elevator frame also.
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The range of the excitation energy used in the experiment (PIFS) for detecting the fluorescence of water after excitation with synchrotron radiation is from 532 ev to 542 ev. The cross section fluorescence curve show that there is an increase in the fluorescence just above the threshold ionization. This kind of feature appeared also in the case of the CO2 but only after the shake-up photoionization (in the range of 540-590 ev) and the people explain that due to the resonance in shake-up satellites which may increase the number of excited fragments and then enhance fluorescence.
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The binding energy of the oxygen 1s electron is around 543 eV. X-rays with energy above this value are more strongly absorbed than those with energy below this value, as the 1s electron can absorb all this energy and be removed from the atom, becoming a photo-electron. This leaves behind a hole in the 1s level. As higher energy electrons fill this hole, they emit light at characteristic energies given by the difference in the electron binding energies.
Perhaps you're asking a more subtle question? The probability of absorbing an X-ray with energies near the binding energy level can be complicated by both chemical environment (NEXAFS/XANES) and by multi-electron excitations (shake-up, and so on).
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I am looking at the design of a turnaround loop and I have a position and angle feed forward system designed with BPMs upstream of the turnaround loop and kickers downstream. Synchrotron radiation will cause some uncorrelated jitter between the BPMs and the kickers and I need to be able to quantify this jitter in terms of the synchrotron radiation in the loop so I can design the optics. Does anyone have any information or links to useful papers. Help would be greatly appreciated.
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You may find the answer in a recent paper out of Cornell. Please see the preprint at the following url: http://www.lns.cornell.edu/~dlr/papers/1-s2.0-S0168900212014441-main.pdf
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In accelerator physics where we study/control the electron beam in the storage ring, we describe magnetic elements with matrices and have some math and terminology to describe the optics (e.g. beta functions or Twiss parameters, emittance, etc). The electron beam produces a photon beam that then goes down the beamline. I understand one can use a ray tracing code to follow the photons through mirrors, CRL's etc. And one talks of focusing optics and other optics. But is there a commonly used matrix formalism to describe the linear optics of beamlines? Can someone point me to a reference?
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Transport of electrons in a beam line is quite similar to transport of light in a focusing system. The Rayleigh range corresponds to the Twiss beta function... Read this reference ... Dattoli et al. Il Nuovo Cimento D, March 1992, Volume 14, Issue 3, pp 271-278 Towards a wave theory of charged-beam propagation.