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Case File Copy NASA TECHNICAL MEMORANDUM NASA TA4 X-53991. CASE FILE COPY A SOLAR X-RAY ASTRONOMY SUMMARY AND B I BL IOGRAPHY By Robert M. Wilson John M. Reynolds Stanley A. Fields Space Sciences Laboratory January 1970 NASA George C. Marshall Space Flight Center Marshall Space Flight Center, Alabama MSFC - Form ,3190 (September 1968) TABLE OF CONTENTS Page INTRODUCTION .................................... 1 BIBLIOGRAPHY.................................... 3 AUTHORINDEX .................................... 83 SUBJECTINDEX ................................... 87 APPENDIX ....................................... 90 LIST OF TABLES Table Title Page A.1 . Tabulation of Rocket and Balloon Solar X-Ray Flight Experiments ................................. 91 A.2 . Tabulation of Satellite Solar X-Ray Flight Experiments .... 94 A.3 . Tabulation of Observed Solar Spectral Lines ( 1- to 100-8) by Flight Experiment ........................... 96 0 A.4 . List of Observed Solar Spectral Lines (I- to iOO-A) ...... 114 DEFINITION OF SYMBOLS Symbol Definition Crystals: CaFz Calcium fluoride CaS04:Mn Calcium sulfate: manganese EDDT Ethylene diamine d-tartrate KA P Potassium acid phthallate LiF Lithium fluoride ML 1VIagnesium lignocerate (multilayer film) NaI Sodium iodide NaI(T1) Sodium iodide (thallium ) OHS Octadecyl hydrogen succinate Elements: A1 Aluminum Ar Argon B Boron Be Beryllium C C arbon Ca C alc ium C I Chlorine Cr Chronlium DEFINITION OF SYMBOLS (Continued) Symbol Definition Elements: F Fluorine Fe Iron H Hydrogen He Helium Li Lithium Mg Magnesium Mn Manganese N Nitrogen Na Sodium Ne Neon Ni Nickel 0 Oxygen S Sulfur Si Silicon T 1 Thallium Others: E Energy hv Photon energy CPlanckls constant x frequency) BEFI N ITION OF SYMBOLS (Concluded) Definition Others: mc2 Energy (mass x velocity of light squared) h Wavelength Incidence angle Focal length Distance Degrees of arc, minutes of arc, seconds of arc Greater than Greater than or equal to Less than Less than or equal to Approximately Approximately equal to Equal to Calcium K line (resonance) Hydrogen line (resonance) Characteristic X-ray emission Pi (3,1415927) LIST OF ABBREVIATIONS Abbreviation Definition Groups: AFCRL Air Force Cambridge Research Laboratory ARUCL Astrophysics Research Unit Culham Laboratory ASE American Science and Engineering CSRL Convair Scientific Research Laboratory ESRO European Space Research Organization GSFC Goddard Space Flight Center HA0 High Altitude Observatory HCO Harvard College Observatory LASL Los Alamos Scientific Laboratory MSFC Marshall Space Flight Center MSSL Mullard Space Science Laboratory NASA National Aeronautics and Space Administration NRL Naval Research Laboratory Ionosphere: CR Cosmic-ray SCNA Sudden cosmic noise absorption SEA Sudden enhancement of (low frequency) atmospherics sfe Solar flare effect vii Abbreviation Definition Ionosphere: SID Sudden ionospheric disturbance SWF Short-wave fadeout Measurements: W Angstrom AA Angstrom band A. U. Astronomical Unit nlm Millimeter cm Centimeter km Kilometer in. Inch eV Electron volt keV I<iloelectron volt MeV Megaelectron volt MHz Megahertz Mc Megacycle Mc/sec Megacycle per second " K Degrees Kelvin " C Degrees C entigrade viii LIST OF ABBREVIATIONS (Continued) Abbreviation Definition Measurements: UT Universal Time MST Mountain Standard Time m in Minute sec Second lb Pound Satellite-Rocket: ATM Apollo Telescope Mount IMP Interplanetary Monitoring Probe IRIS International Radiation Investigation Satellite OGO Orbiting Geophysical Observatory OSO Orbiting Solar Observatory SL Skylark SOLRAD, SR Solar Radiation UK United Kingdom (Ariel ) Tabular : SC Solar condition A Active Q Quiet LIST OF ABBREVIATIONS (Continued) Abbreviation Definition Tabular: R Rocket B Balloon S Satellite CRG Cosmic-ray group Obs. Observatory Ref Reference No. Number Uid. Unidentified LY Lyman Diff. grating spect. Diffraction grating spectrograph spect. Spectrograph photo. Photonieter g. i. Grazing incidence g. i. spect. Grazing incidence spectrograph g. i. s. Grazing incidence spectrometer p. c. Proportional counter p. c. s. Proportional counter spectronieter LIST OF ABBREVIATIONS (Continued) Abbreviation Definition Tabular: Pulse height analyzer Pulse height counter Ionization chamber S. C. Scintillation counter B. c. s. Bragg crystal spectrometer G. c. Geiger counter Others: a! Alpha P Beta Y Gamma 6 Delta cm-h C entimeter-wavelength B, L Heliographic coordinates IQSY International Quiet Sun Year IGY International Geophysical Year IGC International Geophysical Cooperation NE Northeast %\TW Northwest LIST OF ABBREVIATIONS (Concluded) Abbreviation Definition Others: f-f Free-free f-b Free-bound Temperature Electron temperature EUV, XW Extreme ultraviolet Ultraviolet Electrons Electron density Volume Transition Ratio of silicon atoms to hydrogen atoms xii TECHNICAL MEMORANDUM X-53991 A SOLAR X-RAY ASTRONOMY SUMMARY AND B I BLI OGRAPHY This review summarizes the results of the solar X-ray astronomy work that has been reported in the literature. Included are tables prepared from the surveyed literature, which are used to summarize certain information con- cerning the X-ray Sun. Also included is a bibliography, an author index, and a subject index. The bibliographic section represents the working body of the report. It is arranged in alphabetical order by author, and each abstract is preceded by the abstract number. This number is the key to the abstract-cross-reference system. For example, one wishing to find all articles written by L. W. Acton in this review would turn to the author index, find Actonfs name, and list the abstract number or numbers indexed beside the reference. This number refers to the abstract contained in the body of the report. Likewise, one wishing to determine all articles concerning balloon X-ray flight experiments would refer to the subject index under the heading "X-Ray Flight Experiments" and under the subheading "Balloonff. These numbers are the abstract numbers. Four interrelated tables were constructed from the surveyed literature and are included in the appendix. Table A- i , Tabulation of Rocket and Balloon Solar X-Ray Flight Experiments, lists by date and time (UT)the solar X-ray rocket and balloon flight experiments contained within this review. Other information included in the table are solar condition (SC) , investigoating group (Lab), designation of project, instrumentation, Angstrom band (AA) , and references (Ref). The numbers in the reference column refer to the abstracts. Table A-2, Tabulation of Satellite Solar X-Ray Flight Experiments, lists by satellite designation the various satellite solar X-ray experiments. This table is similar to Table A-I in that the period of observation, the instrumentation, the Angstrom band and the references are included as well. Again, the numbers in the reference column refer to the abstracts. Table A-3, Tabulation of Observed Solar Spectral Lines (I-to 100-A) by Flight Experiment, lists by date of observation the observed solar spectral 0 lines (A observed) in the 1- to 100-A region. Also included are type of flight experinlent (R, B, S), predicted wavelength (A predicted), ion, transition, remarks, and references (references again refer to the abstracts). The number colw1111 (No. ) enumerates the flights from earliest (1) to most recent ( I1) . This number cross-references Tables A-3 and A-4. Table A-4, List of Observed Solar Spectral Lines (1- to 100-A), lists observed solar spectral lines (A observed) from shortest wavelength (1.91-A) to longest wavelength (98. 24-A). Included in this table are the ions and pre- dicted wavelengths (A predicted), which nlay be identified with the observed spectral lines. The numbt>~-column (No. ) cross-references with Table A-3. These four tables comprise the appendix section of the review and are definitely interrelated. Tnble A-3 is connected to tables A- I and A-2 by the date or period of observation and the R, B, S column, which signifies a rocket, balloon or satellite flight experiment. Table A-4 is related to Table A-3 by the nunlber column (No. ) and represents a reordering of the data contained in Table A-3. To exhibit the interrelationships arnoung the tables an example is given. Suppose one wishes to obtain more information about an observed spectral line listed in Table A-4. From this table he has already secured the ion or ions and their predicted wavelengths that may be associated with the observed line in question. Also, he has a cross-reference to Table A-3, the No. colunln, which will give him nlore data. From Table A-3 he learns when the spectral data was obtained and the type of flight experiment it was (R, B, S). The transition of the ion identified with the observed spectral line may be given as well as any useful remarks. From this table he also is referred to the abstract-bibliography by t.he reference column. Knowing the date of observation and the type of flight experiment, he can go to Tables A-I and A-2 and determine the solar condition at the time of observation, the investigating group (Table A- I ) the instrumentation, and the Angstrom band. He is also referred to the abstracts by the reference column. The bibliography contains abstracts from 153 papers related to solar X-ray astronomy. It is realized that all articles that may have been published have not been included; however, the articles reviewed provide a comprehensive summary of solar X-ray astronomy. 1. Acton, L. W. : Contribution of Characteristic X-Rays to the Radiation of Solar Flares. Nature, vol. 207, Aug. 1965, pp. 737-738. The
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