Hot electron and x-ray production from intense laser irradiation of wavelength-scale polystyrene spheres

Abstract Fast electrons created as a result of the laser beam interaction with a solid target penetrate into the target material and initialize processes leading to the generation of the characteristic X-ray K-α radiation. Due to the strong electric field induced at the rear side of a thin target the transmitted electrons are redirected back into the target. These refluxing electrons increase the K-α radiation yield, as well as the duration of the X-ray pulse and the size of the radiation emitting area. A model describing the electron refluxing was verified via particle-in-cell simulations for non-relativistic electron energies. Using this model it was confirmed that the effect of the electron refluxing on the generated X-ray radiation depends on the target thickness and the target material. A considarable increase of the number of the emitted K-α photons is observed especially for thin targets made of low-Z materials, and for higher hot electron temperatures.

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Hot electron generation from intense laser irradiation of microtipped cone and wedge targets

Physics of Plasmas ◽

10.1063/1.2912457 ◽

2008 ◽

Vol 15 (5) ◽

pp. 052701 ◽

Cited By ~ 9

Author(s):

B. I. Cho ◽

G. M. Dyer ◽

S. Kneip ◽

S. Pikuz ◽

D. R. Symes ◽

...

Keyword(s):

Laser Irradiation ◽

Intense Laser ◽

Hot Electron ◽

Electron Generation

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Electron Heating by Ultra-Fast, Ultra-Intense Laser Irradiation of Wavelength-Scale Wires

CLEO: 2015 ◽

10.1364/cleo_at.2015.jw2a.41 ◽

2015 ◽

Author(s):

Kristina Serratto ◽

Franki Aymond ◽

Brandon Simon ◽

Aaron Bernstein ◽

Todd Ditmire

Keyword(s):

Laser Irradiation ◽

Intense Laser ◽

Electron Heating ◽

Wavelength Scale

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Scanning luminescence x-ray microscopy: Progress toward selective staining using microspheres

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100168104 ◽

1994 ◽

Vol 52 ◽

pp. 74-75

Author(s):

C. Jacobsen ◽

J. Fu ◽

S. Mayer ◽

Y. Wang ◽

S. Williams

Keyword(s):

Visible Light ◽

Active Sites ◽

Light Emission ◽

Chinese Hamster ◽

Polystyrene Spheres ◽

Good Resistance ◽

X Ray ◽

Selective Staining ◽

Visible Light Emission ◽

Specific Labelling

In scanning luminescence x-ray microscopy (SLXM), a high resolution x-ray probe is used to excite visible light emission (see Figs. 1 and 2). The technique has been developed with a goal of localizing dye-tagged biochemically active sites and structures at 50 nm resolution in thick, hydrated biological specimens. Following our initial efforts, Moronne et al. have begun to develop probes based on biotinylated terbium; we report here our progress towards using microspheres for tagging.Our initial experiments with microspheres were based on commercially-available carboxyl latex spheres which emitted ~ 5 visible light photons per x-ray absorbed, and which showed good resistance to bleaching under x-ray irradiation. Other work (such as that by Guo et al.) has shown that such spheres can be used for a variety of specific labelling applications. Our first efforts have been aimed at labelling ƒ actin in Chinese hamster ovarian (CHO) cells. By using a detergent/fixative protocol to load spheres into cells with permeabilized membranes and preserved morphology, we have succeeded in using commercial dye-loaded, spreptavidin-coated 0.03μm polystyrene spheres linked to biotin phalloidon to label f actin (see Fig. 3).

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Effect of a Laser irradiation on the vascularisation of safety and X-ray radiated bone

2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society ◽

10.1109/iembs.2007.4353677 ◽

2007 ◽

Author(s):

Sophie Desmons ◽

Caroline Delfosse ◽

Philippe Rochon ◽

Bruno Buys ◽

Guillaume Penel ◽

...

Keyword(s):

Laser Irradiation ◽

X Ray

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Carbon-coated magnetic particles increase tissue temperatures after laser irradiation

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545815500182 ◽

2015 ◽

Vol 08 (05) ◽

pp. 1550018 ◽

Cited By ~ 1

Author(s):

Shupeng Liu ◽

Na Chen ◽

Fufei Pang ◽

Zhengyi Chen ◽

Tingyun Wang

Keyword(s):

Laser Irradiation ◽

Magnetic Particles ◽

Laser Energy ◽

Thermal Therapy ◽

Vibrating Sample Magnetometer ◽

X Ray Diffraction ◽

X Ray ◽

Fbg Sensor ◽

Transmission Electron ◽

Carbon Coated

Purpose: This work focused on the investigation the hyperthermia performance of the carbon-coated magnetic particles (CCMPs) in laser-induced hyperthermia. Materials and methods: We prepared CCMPs using the organic carbonization method, and then characterized them with transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectrophotometry, vibrating sample magnetometer (VSM) and X-ray diffraction (XRD). In order to evaluate their performance in hyperthermia, the CCMPs were tested in laser-induced thermal therapy (LITT) experiments, in which we employed a fully distributed fiber Bragg grating (FBG) sensor to profile the tissue's dynamic temperature change under laser irradiation in real time. Results: The sizes of prepared CCMPs were about several micrometers, and the LITT results show that the tissue injected with the CCMPs absorbed more laser energy, and its temperature increased faster than the contrast tissue without CCMPs. Conclusions: The CCMPs may be of great help in hyperthermia applications.

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