Characteristics of Solar Flare Doppler‐Shift Oscillations Observed with the Bragg Crystal Spectrometer onYohkoh

AbstractDiogeness was an uncollimated scanning flat crystal spectrometer observing solar flare X-ray spectra in four narrow wavelength bands in the vicinity of Ca xix, S xv and Si xiii He-like line ‘triplets’ around 3.18 Å, 5.04 Å and 6.65 Å. In two of the spectral channels, emission lines around the Ca xix 3.178 Å resonance line were scanned in opposite directions, being diffracted from precisely adjusted identical Quartz crystals mounted on a common shaft in a so-called Dopplerometer (tachometer) configuration. Observations of solar X-ray spectra made by Diogeness provide a direct diagnostic information on plasma characteristics during the impulsive flare energy release. We present a sample of events which occurred during the Diogeness operation time from August 16, 2001 to September 17, 2001.

Download Full-text

Lifetimes and decay modes of energy levels in 25Mg

Canadian Journal of Physics ◽

10.1139/p68-550 ◽

1968 ◽

Vol 46 (18) ◽

pp. 2039-2053 ◽

Cited By ~ 36

Author(s):

J. F. Sharpey-Schafer ◽

R. W. Ollerhead ◽

A. J. Ferguson ◽

A. E. Litherland

Keyword(s):

Gamma Rays ◽

Doppler Shift ◽

Energy Levels ◽

Branching Ratios ◽

Collective Model ◽

Incident Proton ◽

Crystal Spectrometer ◽

Decay Modes ◽

Mirror Nucleus ◽

Doppler Shift Attenuation

Lifetimes of energy levels in 25Mg have been measured using the Doppler-shift attenuation method. The levels were exicted by the 25Mg(p, p′γ) reaction with incident proton energies between 3.8 and 7.0 MeV. The gamma rays were detected in a three-crystal spectrometer consisting of a 40 cm3 Ge(Li) detector surrounded by a large NaI(Tl) crystal in the form of a split annulus. Mean lifetimes found, given in fs, are: τ(1611-keV level) = [Formula: see text], τ(1962) = [Formula: see text], τ(2565) = 59 ± 26, τ(2736) = 288 ± 20, τ(2803) = 27 ± 6, τ(3399) = 33 ± 19, τ(3408) < 20, τ(3903) < 20, τ(3969) = 24 ± 11, τ(4055) = 53 ± 10, and τ(5005) < 26. The decay modes and branching ratios of levels up to 4055-keV excitation are given. The results are compared with the mirror nucleus 25Al and discussed in terms of the collective model.

Download Full-text

Solar flare X-ray spectra from the Solar Maximum Mission Flat Crystal Spectrometer

The Astrophysical Journal ◽

10.1086/159950 ◽

1982 ◽

Vol 256 ◽

pp. 774 ◽

Cited By ~ 122

Author(s):

K. J. H. Phillips ◽

B. C. Fawcett ◽

B. J. Kent ◽

A. H. Gabriel ◽

J. W. Leibacher ◽

...

Keyword(s):

Solar Flare ◽

Solar Maximum ◽

Crystal Spectrometer ◽

Solar Maximum Mission ◽

X Ray

Download Full-text

A Unique Resource for Solar Flare Diagnostic Studies: The SMM Bent Crystal Spectrometer

The Astrophysical Journal ◽

10.3847/1538-4357/ab86ba ◽

2020 ◽

Vol 894 (2) ◽

pp. 137

Author(s):

J. Sylwester ◽

B. Sylwester ◽

K. J. H. Phillips ◽

A. Kępa ◽

C. G. Rapley

Keyword(s):

Solar Flare ◽

Crystal Spectrometer ◽

Bent Crystal ◽

Diagnostic Studies

Download Full-text

CHIANTI—An Atomic Database for Emission Lines. VIII. Comparison with Solar Flare Spectra from the Solar Maximum Mission Flat Crystal Spectrometer

The Astrophysical Journal Supplement Series ◽

10.1086/506180 ◽

2006 ◽

Vol 166 (1) ◽

pp. 421-440 ◽

Cited By ~ 30

Author(s):

E. Landi ◽

K. J. H. Phillips

Keyword(s):

Solar Flare ◽

Solar Maximum ◽

Emission Lines ◽

Crystal Spectrometer ◽

Solar Maximum Mission

Download Full-text

Solar Flare Energetic Neutral Emission Measurements in the Project Coronas-I

International Astronomical Union Colloquium ◽

10.1017/s0252921100026208 ◽

1994 ◽

Vol 144 ◽

pp. 635-639

Author(s):

J. Baláž ◽

A. V. Dmitriev ◽

M. A. Kovalevskaya ◽

K. Kudela ◽

S. N. Kuznetsov ◽

...

Keyword(s):

Solar Flare ◽

Energy Range ◽

Gamma Rays ◽

Pulse Shape ◽

Gamma Ray ◽

Pulse Shape Discrimination ◽

Shape Discrimination ◽

Solar Neutron ◽

Low Altitude

AbstractThe experiment SONG (SOlar Neutron and Gamma rays) for the low altitude satellite CORONAS-I is described. The instrument is capable to provide gamma-ray line and continuum detection in the energy range 0.1 – 100 MeV as well as detection of neutrons with energies above 30 MeV. As a by-product, the electrons in the range 11 – 108 MeV will be measured too. The pulse shape discrimination technique (PSD) is used.

Download Full-text