Time and space resolved modelling of the heating induced by synchrotron X-ray nanobeams

2020 ◽  
Vol 27 (6) ◽  
pp. 1662-1673
Author(s):  
Valentina Bonino ◽  
Daniele Torsello ◽  
Carmelo Prestipino ◽  
Lorenzo Mino ◽  
Marco Truccato

X-ray synchrotron sources, possessing high power density, nanometric spot size and short pulse duration, are extending their application frontiers up to the exploration of direct matter modification. In this field, the use of atomistic and continuum models is now becoming fundamental in the simulation of the photoinduced excitation states and eventually in the phase transition triggered by intense X-rays. In this work, the X-ray heating phenomenon is studied by coupling the Monte Carlo method (MC) with the Fourier heat equation, to first calculate the distribution of the energy absorbed by the systems and finally to predict the heating distribution and evolution. The results of the proposed model are also compared with those obtained removing the explicit definition of the energy distribution, as calculated by the MC. A good approximation of experimental thermal measurements produced irradiating a millimetric glass bead is found for both of the proposed models. A further step towards more complex systems is carried out, including in the models the different time patterns of the source, as determined by the filling modes of the synchrotron storage ring. The two models are applied in three prediction cases, in which the heating produced in Bi2Sr2CaCu2O8+δ microcrystals by means of nanopatterning experiments with intense hard X-ray nanobeams is calculated. It is demonstrated that the temperature evolution is strictly connected to the filling mode of the storage ring. By coupling the MC with the heat equation, X-ray pulses that are 48 ps long, possessing an instantaneous photon flux of ∼44 × 1013 photons s−1, were found to be able to induce a maximum temperature increase of 42 K, after a time of 350 ps. Inversely, by ignoring the energy redistribution calculated with the MC, peaks temperatures up to hundreds of degrees higher were found. These results highlight the importance of the energy redistribution operated by primary and secondary electrons in the theoretical simulation of the X-ray heating effects.

2014 ◽  
Vol 70 (a1) ◽  
pp. C1733-C1733
Author(s):  
Martin Fuchs ◽  
Robert Sweet ◽  
Lonny Berman ◽  
Dileep Bhogadi ◽  
Wayne Hendrickson ◽  
...  

We present the final design of the x-ray optical systems and experimental stations of the two macromolecular crystallography (MX) beamlines, FMX and AMX, at the National Synchrotron Light Source-II (NSLS-II). Along with its companion x-ray scattering beamline, LIX, this suite of Advanced Beamlines for Biological Investigations with X-rays (ABBIX, [1]) will begin user operation in 2016. The pair of MX beamlines with complementary and overlapping capabilities is located at canted undulators (IVU21) in sector 17-ID. The Frontier Microfocusing Macromolecular Crystallography beamline (FMX) will deliver a photon flux of ~5x10^12 ph/s at a wavelength of 1 Å into a spot of 1 - 50 µm size. It will cover a broad energy range from 5 - 30 keV, corresponding to wavelengths from 0.4 - 2.5 Å. The highly Automated Macromolecular Crystallography beamline (AMX) will be optimized for high throughput applications, with beam sizes from 4 - 100 µm, an energy range of 5 - 18 keV (0.7 - 2.5 Å), and a flux at 1 Å of ~10^13 ph/s. Central components of the in-house-developed experimental stations are a 100 nm sphere of confusion goniometer with a horizontal axis, piezo-slits to provide dynamic beam size changes during diffraction experiments, a dedicated secondary goniometer for crystallization plates, and sample- and plate-changing robots. FMX and AMX will support a broad range of biomedical structure determination methods from serial crystallography on micron-sized crystals, to structure determination of complexes in large unit cells, to rapid sample screening and data collection of crystals in trays, for instance to characterize membrane protein crystals and to conduct ligand-binding studies. Together with the solution scattering program at LIX, the new beamlines will offer unique opportunities for advanced diffraction experiments with micro- and mini-beams, with next generation hybrid pixel array detectors and emerging crystal delivery methods such as acoustic droplet ejection. This work is supported by the US National Institutes of Health.


Author(s):  
Tetsuya Ishikawa

The evolution of synchrotron radiation (SR) sources and related sciences is discussed to explain the ‘generation’ of the SR sources. Most of the contemporary SR sources belong to the third generation, where the storage rings are optimized for the use of undulator radiation. The undulator development allowed to reduction of the electron energy of the storage ring necessary for delivering 10 keV X-rays from the initial 6–8 GeV to the current 3 Gev. Now is the transitional period from the double-bend-achromat lattice-based storage ring to the multi-bend-achromat lattice to achieve much smaller electron beam emittance. Free electron lasers are the other important accelerator-based light sources which recently reached hard X-ray regime by using self-amplified spontaneous emission scheme. Future accelerator-based X-ray sources should be continuous wave X-ray free electron lasers and pulsed X-ray free electron lasers. Some pathways to reach the future case are discussed. This article is part of the theme issue ‘Fifty years of synchrotron science: achievements and opportunities’.


1984 ◽  
Vol 17 (5) ◽  
pp. 337-343 ◽  
Author(s):  
O. Yoda

A high-resolution small-angle X-ray scattering camera has been built, which has the following features. (i) The point collimation optics employed allows the scattering cross section of the sample to be directly measured without corrections for desmearing. (ii) A small-angle resolution better than 0.5 mrad is achieved with a camera length of 1.6 m. (iii) A high photon flux of 0.9 photons μs−1 is obtained on the sample with the rotating-anode X-ray generator operated at 40 kV–30 mA. (iv) Incident X-rays are monochromated by a bent quartz crystal, which makes the determination of the incident X-ray intensity simple and unambiguous. (v) By rotation of the position-sensitive proportional counter around the direct beam, anisotropic scattering patterns can be observed without adjusting the sample. Details of the design and performance are presented with some applications.


1995 ◽  
Vol 39 ◽  
pp. 103-107
Author(s):  
W. Z. Chang ◽  
F. N. Chukhovskii ◽  
E. Förster

Micron or submicron spatial resolution for x-ray microfluorescence analysis has been pursued using various x-ray point focusing methods,1-4 such as transmission zone plates, tapered capillaries, and Bragg Fresnel lenses. Point focusing using bent crystals does not seem to be a desirable means for achieving a microbeam size, although it is a traditional technique which utilizes perfectly curved crystal surfaces to focus x rays emanating from the source. It is known that point focusing can only be achieved by bending a crystal two dimensionally, which normally introduces imperfections to the crystal since the crystal is an undevelopable surface. Unavoidably, the introduced imperfections will broaden the reflection curve (rocking curve) of the crystal and, in turn, broadens the focal spot size.


2014 ◽  
Vol 21 (5) ◽  
pp. 961-967 ◽  
Author(s):  
Xiaobiao Huang ◽  
Thomas Rabedeau ◽  
James Safranek

Approaches to generating short X-ray pulses in synchrotron light sources are discussed. In particular, the method of using a superconducting harmonic cavity to generate simultaneously long and short bunches in storage rings and the approach of injecting short bunches from a linac injector into a storage ring for multi-turn circulation are emphasized. If multi-cell superconducting RF (SRF) cavities with frequencies of ∼1.5 GHz can be employed in storage rings, it would be possible to generate stable, high-flux, short-pulse X-ray beams with pulse lengths of 1–10 ps (FWHM) in present or future storage rings. However, substantial challenges exist in adapting today's high-gradient SRF cavities for high-current storage ring operation. Another approach to generating short X-ray pulses in a storage ring is injecting short-pulse electron bunches from a high-repetition-rate linac injector for circulation. Its performance is limited by the microbunching instability due to coherent synchrotron radiation. Tracking studies are carried out to evaluate its performance. Challenges and operational considerations for this mode are considered.


2013 ◽  
Vol 32 (1) ◽  
pp. 9-14 ◽  
Author(s):  
Manoj Kumar ◽  
Rohtash Singh ◽  
Updesh Verma

AbstractA theoretical model of soft X-ray emission from laser irradiated clusters is developed. An intense short pulse laser of Gaussian radial and temporal profiles impinged on a clustered gas jet, heats the cluster electrons, leading to Bremsstrahlung emission of X-rays. As the clusters expand under hydrodynamic pressure, plasma frequency of the cluster electrons ωpedecreases. When plasma frequency of a cluster approaches plasma resonance${\rm \omega}_{\,pe} = \sqrt{3} {\rm \omega}$(where ω is the laser frequency), the electrons are resonantly heated by the laser and a rapid rise in X-ray emission occurs. After a while, when cluster expansion detunes the plasma resonance, X-ray emission falls off.


1998 ◽  
Vol 524 ◽  
Author(s):  
S. Tamura ◽  
K. Ohtani ◽  
M. Yasumoto ◽  
K. Murali ◽  
N. Kamuo ◽  
...  

ABSTRACTA hard X-ray microbeam with submicrometer spot size from synchrotron radiation (SR) sources is expected to add a new dimension to various X-ray analysis methods. A Fresnel zone plate (FZP) is one of the promising focusing elements for X-rays. In order to develop high performance multilayer FZP for use in the hard X-ray region, Cu/Al concentric multilayers were fabricated by use of a DC sputtering deposition process. Lower Ar gas pressure or higher rotating speed of a wire substrate has been effective in forming smoother multilayer interfaces. From a focusing test of the Cu/Al FZP (100-zones) by the SR (λ= 0.154nm), microbeams of 1.5 μm φ and 0.8 μm φ have been achieved for the first- and third-order focal beams, respectively.


2002 ◽  
Vol 17 (2) ◽  
pp. 70-80 ◽  
Author(s):  
Paul J. Schields ◽  
David M. Gibson ◽  
Walter M. Gibson ◽  
Ning Gao ◽  
Huapeng Huang ◽  
...  

Polycapillary optics are utilized in a wide variety of applications and are integral components in many state of the art instruments. Polycapillary optics operate by collecting X-rays and efficiently propagating them by total external reflection to form focused and parallel beams. We discuss the general parameters for designing these optics and provide specific examples on balancing the interrelations of beam flux, source size, focal spot-size, and beam divergence. The development of compact X-ray sources with characteristics tailored to match the requirements of polycapillary optics allows substantial reduction in size, weight, and power of complete X-ray systems. These compact systems have enabled the development of portable, remote, and in-line sensors for applications in industry, science and medicine. We present examples of the utility and potential of these optics for enhancing a wide variety of X-ray analyses.


2017 ◽  
Vol 35 (3) ◽  
pp. 442-449 ◽  
Author(s):  
R. Rathore ◽  
V. Arora ◽  
H. Singhal ◽  
T. Mandal ◽  
J.A. Chakera ◽  
...  

AbstractKα X-ray sources generated from the interaction of ultra-short laser pulses with solids are compact and low-cost source of ultra-short quasi-monochromatic X-rays compared with synchrotron radiation source. Development of collimated ultra-short Kα X-ray source by the interaction of 45 fs Ti:sapphire laser pulse with Cu wire target is presented in this paper. A study of the Kα source with laser parameters such as energy and pulse duration was carried out. The observed Kα X-ray photon flux was ~2.7 × 108 photons/shot at the laser intensity of ~2.8 × 1017 W cm−2. A model was developed to analyze the observed results. The Kα radiation was coupled to a polycapillary collimator to generate a collimated low divergence (0.8 mrad) X-ray beam. Such sources are useful for time-resolved X-ray diffraction and imaging studies.


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