Relative Timing of Soft X-Ray Nonthermal Line Broadening and Hard X-Ray Emission in Solar Flares

1998 ◽  
Vol 494 (2) ◽  
pp. L235-L238 ◽  
Author(s):  
David Alexander ◽  
Louise K. Harra-Murnion ◽  
Josef I. Khan ◽  
Sarah A. Matthews
Keyword(s):  
Solar Flares ◽  
Relative Timing ◽  
Line Broadening ◽  
X Ray

Particle acceleration and the decay of soft X-ray non-thermal line broadening in solar flares

Solar Physics ◽  
1994 ◽  
Vol 154 (1) ◽  
pp. 157-175 ◽  
Author(s):  
David Alexander ◽  
Sarah A. Matthews
Keyword(s):  
Particle Acceleration ◽  
Solar Flares ◽  
Line Broadening ◽  
X Ray ◽  
Thermal Line

The occurrence of single hard x-ray sources in solar flares

2003 ◽  
Vol 32 (12) ◽  
pp. 2483-2488
Author(s):  
C GOFF ◽  
S MATTHEWS ◽  
L HARRA
Keyword(s):  
Solar Flares ◽  
X Ray

Nondestructive Inspection of Thin, Low-Z Samples using Multiplexed Compton Scatter Tomography

1997 ◽  
Vol 503 ◽  
Author(s):  
B. L. Evans ◽  
J. B. Martin ◽  
L. W. Burggraf
Keyword(s):  
Signal To Noise Ratio ◽  
Reconstruction Algorithm ◽  
Filtered Backprojection ◽  
Line Broadening ◽  
Compton Scatter ◽  
X Ray ◽  
Tomography System ◽  
Transmission Computed Tomography ◽  
High Purity Germanium ◽  
Scattered Energy

ABSTRACTThe viability of a Compton scattering tomography system for nondestructively inspecting thin, low Z samples for corrosion is examined. This technique differs from conventional x-ray backscatter NDI because it does not rely on narrow collimation of source and detectors to examine small volumes in the sample. Instead, photons of a single energy are backscattered from the sample and their scattered energy spectra are measured at multiple detector locations, and these spectra are then used to reconstruct an image of the object. This multiplexed Compton scatter tomography technique interrogates multiple volume elements simultaneously. Thin samples less than 1 cm thick and made of low Z materials are best imaged with gamma rays at or below 100 keV energy. At this energy, Compton line broadening becomes an important resolution limitation. An analytical model has been developed to simulate the signals collected in a demonstration system consisting of an array of planar high-purity germanium detectors. A technique for deconvolving the effects of Compton broadening and detector energy resolution from signals with additive noise is also presented. A filtered backprojection image reconstruction algorithm with similarities to that used in conventional transmission computed tomography is developed. A simulation of a 360–degree inspection gives distortion-free results. In a simulation of a single-sided inspection, a 5 mm × 5 mm corrosion flaw with 50% density is readily identified in 1-cm thick aluminum phantom when the signal to noise ratio in the data exceeds 28.

Statistical analysis of soft X-ray solar flares during solar cycles 22, 23, and 24

2021 ◽  
Vol 366 (1) ◽  
Author(s):  
Bo Xiong ◽  
Ting Wang ◽  
Xiaolin Li ◽  
Yunxing Yin
Keyword(s):  
Statistical Analysis ◽  
Solar Flares ◽  
Solar Cycles ◽  
X Ray

Temperature-induced structural phase transitions in RERhSn (RE = Y, Gd-Tm, Lu)

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Simon Engelbert ◽  
Rolf-Dieter Hoffmann ◽  
Jutta Kösters ◽  
Steffen Klenner ◽  
Rainer Pöttgen
Keyword(s):  
Rare Earth ◽  
Phase Transitions ◽  
Driving Force ◽  
Room Temperature ◽  
Structural Phase ◽  
Structural Phase Transitions ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray

Abstract The structures of the equiatomic stannides RERhSn with the smaller rare earth elements Y, Gd-Tm and Lu were reinvestigated on the basis of temperature-dependent single crystal X-ray diffraction data. GdRhSn crystallizes with the aristotype ZrNiAl at 293 and 90 K. For RE = Y, Tb, Ho and Er the HP-CeRuSn type (approximant with space group R3m) is already formed at room temperature, while DyRhSn adopts the HP-CeRuSn type below 280 K. TmRhSn and LuRhSn show incommensurate modulated variants with superspace groups P31m(1/3; 1/3; γ) 000 (No. 157.1.23.1) (γ = 3/8 for TmRhSn and γ = 2/5 for LuRhSn). The driving force for superstructure formation (modulation) is a strengthening of Rh–Sn bonding. The modulation is expressed in a 119Sn Mössbauer spectrum of DyRhSn at 78 K through line broadening.

A new microwave/X-ray diagnostic for the thermal phase of solar flares

Solar Physics ◽  
1986 ◽  
Vol 105 (1) ◽  
pp. 87-99 ◽  
Author(s):  
E. J. Schmahl ◽  
M. R. Kundu ◽  
F. T. Erskine
Keyword(s):  
Solar Flares ◽  
X Ray ◽  
Thermal Phase

X-Ray Diffraction Study of Hep Metals. I. Line Broadening in Polycrystalline Cd Powder

1974 ◽  
Vol 29 (12) ◽  
pp. 1771-1777 ◽  
Author(s):  
N. C. Haider ◽  
S. H. Hunter
Keyword(s):  
Room Temperature ◽  
Small Deformation ◽  
Correction Factors ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
Fault Probability ◽  
Large Particle Size ◽  
X Ray ◽  
Melting Temperatures ◽  
Diffraction Patterns

Powder Cd of 99.999% purity was prepared at room temperature (25 °C) and x-ray diffraction patterns were obtained using CuKaα radiation with Ni-filter. The line broadening was analyzed after incorporating the appropriate correction factors. At room temperature Cd was found to have large particle size (653 A), small root mean square strain (.001), small deformation fault probability a (.003). and negligible growth fault probability β(0). Compared to other hep metals which have been studied earlier and which have higher melting temperatures, metal Cd is much less affected by mechanical deformation at room temperature.

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