Final Report HARD X-RAY IMAGING GRAPHICS DEVELOPMENT AND LITERATURE SEARCH NASA Contract _ NAS8-36955 D.O. 92 June 1990 - June 1991 Principal Investigator /7 ,, ...... A. Gordon Emslie Physics Department University of Alabama in Huntsville (NASA-CR-l_4277) _ARO X RAY IMAGING N92-25953 GnAPHICS _V_LOPHCNT ANO LITERATURE SEARCH Final R_port, Jun. 1990 - Jun. 1991 Unc|as (hl:_b_Ina Univ.) 17 p r,3/as 0070670 INTRODUCTION From June 1990 through June 1991, work was performed under the NASA contract NAS8-36955. During this time the three objectives of the contract were completed. 1.) A comprehensive literature search of imaging technology and coded aperture imaging as well as relevant topics relating to solar flares. 2.) An analysis of random number generators. 3.) Programming simulation models of hard x-ray telescopes. All programs axe compatible with NASA/MSFC Space Science Laboratory VAX Clus- ter and are written in VAX FORTRAN and VAX IDL (Interactive Data Language). LITERATURE SEARCH A literature search was conducted using the Redstone Scientific Information Center. All relevant materials were collected and indexed according to topic and chronology. These materials were used to support the research of x-ray telescopes as well as hard x-ray emissions from solar flares. (See Appendix A for a list of all reference materials.) RANDOM NUMBER GENERATORS In order to simulate an x-ray telescope, random photons must be generated. It was necessary to insure that the random number generator used in the simulations was in- deed random. Since the programs were to be written in FORTRAN, the reliability of FORTRAN's random number generator was investigated. Two types of programs were created for this task: one using a uniform distribution and the other using a gaussian distribution. IDL programs were then created to display the information. The resulting graphs were then checked for any recognizable patterns. FORTRAN's procedure for generating random numbers, RAN, will generate numbers between 0 and 1. The program WORAN.FOR calls upon RAN to select a random number. It then sequentially assigns the number to either an x or y coordinate. Lastly the program writes these numbers to a data file. The IDL program WORVECTOR.PRO reads this data file and proceeds to plot the x coordinates versus the y coordinates (Figure 1). It was deduced that there were no patterns present. Figure 1 UNIFORM RANDOM NUMBERS, X VS. Y Another checkon the uniform distribution required that a random grid be chosen andfrom there random x andy coordinatesdetermined. This processwould establish the effectivenessof RAN when a few random numbersare required. Using a processsimilar to the oneusedin WORAN.FOR. the program TRIWORAN.FOR wascreated. The IDL program TRIPLOT.PRO wasthen usedto display the information (Figure 2). Again. no patterns wereobserved• Figure 2 UNIFORM RANDOM _u'MBERS X VS. Y--lrlTHOUT RANO PLOT 1 PLOT 2 PLOT 3 t 1 1 • ' • . ,s '° r),_ ,'. -'" ,• 0.5 0.5 _ ,__'-_, ., 0.5 _.:'• .:, -:,¢_.•_-"__ •- _-._&_ "_ _ .. •_..' _ :.-.,,_'",..1,- , . "Q-Mk_ . . ,. _.]t_',., • .,,,,..._.,.-.-_ •._.', _'_.I' __,.t._; t. : 0.0 0.0 0.0 0.5 1 0.0 0.5 1 0.0 0.5 1 To create a gaussian distribution, RAN was used to generate random numbers with an average of zero and a standard deviation of one. This was accomplish in the program GARAN.FOR. Two IDL program were written to display the information. GAUSS.PRO generates a histogram plot of the data points and compares it to the predicted value (Figure 3). GAUSSIAN.PRO generates a scatter plot of the data points and again compares them to the predicted gaussian curve (Figure 4). By looking at the gaussian scatter plot. no patterns can be seen. 3 In all cases,no patterns canbeseen.From this it wasdetermined that FORTRAN's random number generator would be adequatefor generating random photons for the x- ray telescopesimulations. Initially it wasthought that an additional subroutine. RAN0. would haveto be addedto all programsto increasethe reliability of the random number generator. Eachof the tests mentionedabovewereperformed with and without RAN0. It wasdeterminedthat RAN0 did not significantly improve the random number generator andwasthereforedismissed. Figure 3 GAUSSIAH DISTRIBUTION 10,000 POINTS / \ --° m llO0 II L / / II v o.o L, ,do. 94oo 9840 I0o00 10_00 N Figure 4 c_ussa_ _o_ lo.ooo FLUX_(_SUREUENTS 0.8 0.1 0.4 0,2 0.0 • "" r L, , _ . . t ,'-,,'_- _0_ _o2_ N 4 APPENDIX A Bibliography of referencematerials Ables. J.G.-" Fourier Transform Photography: A New Method forX-ray Astronomy" Proc. ASA. Vol. I.No. 4. 1968. pp. 172-173 Almlea_ky. Y. bf.-"Density Diagnostics and Inhomogeneous Plasmas. I.Isothermal Plas- mas'" Astron. and Astroph.. Vol. 224. 1989, pp. 328-337 Bad. T.-"Hard X-ray Time Profiles and Acceleration Processes in Large Solar Flares" AstrophysicM Journal. Vol. 227. 1979, pp. 1072-1081 Batchelor. D. A.-"Evidence for Collisionless Conduction Fronts in Impulsive Solar Flares" Astrophysical Journal. Vol. 295. 1985. pp. 258-274 Bertsch. D. L.-"Instrumentation for Gamma-ray Astronomy" Space Science Reviews, Vol. 48. 1988. pp. 113-168 Bracewell. R. N.-"Inversion of Fan-beam Scans in Radio Astronomy" Astrophysical Jour- nal. \'o1.!150. 1967. pp. 427-434 Bradt. K.-'The N[odulation Collimator in X-ray Astronomy" Space Science Reviews. Vol. 8. !968. pp. 471-506 Brown. D. G.-"Hard X-ray Emission in Electron-heated Solar Flares - A Comparison of Nonthermal and Thermal Contributions" Solar Physics. Vol. 110. 1987, pp. 305-315 Brown. J. C.-"A Classification Scheme for Solar Flare ._Iodels" Solar Physics. Vol. 67, 1980. pp. 385-392 "'A Comparison of the Thick-target .N'lodel with Stereo Data on the Height Structure of Solar Kard X-ray Bursts" Solar Physics. Vot. 88, 1983. pp. 2S1-295 --"'A Lower Limit to the Field Strength in Magnetic Reconnection Sites in Solar Flares Inferred from Hard X-ray Bursts" Astro. and Space Science. Vol. 117. 1985. pp. 173-177 "Analysis of Bremsstrahlung Source Spectra in Terms of Integral 5Ioments" As- trophysical Journal. %'oi. 225, 1978. pp. 1076-1082 "'Analytic Limits on the Forms of Spectra Possible from Optically Thin Collisional Bremsstrahlung Source Models" Astrophysical Journal. Vol. 331. 1988. pp. 554-564 -"Application of the Trap-plus-precipitation Hard X-ray Burst ,Nlodel to the Flare of August 4, 1972" Solar Physics, \,51.63, 1979, pp. 175-185 -"Bremsstrahlung Spectra from Thich-target Electron Beams with Noncollisional Energy Losses" Astrophysical Journal, %'ol. 292, 1985, pp. L31-L34 --"Collisional and Return Current Heating Functions for Beam-heated 5lodels of Solar Flares" Astrophysics and Space Sci., Vol. 133. 1987. pp. 297-306 "Density Diagnostics and Inhomogeneous Plasmas. I. Isothermal Plasmas" Astron. and Astroph.. Voi. 224. 1989, pp. 328-337 -"Discrepancies Between Theoretical and Empirical Models of the Flaring Solar Chromosphere and their Possible Resolution" Astrophysical Journal, %'ol. 246, 1981. pp. 337-343 -----" Dynamic Spectral Characteristics of Thermal Models for Solar Hard X-ray Bursts" Solar Physics. Vol. 67, 1980, pp. 143-162 ---" Fundamental Limitations of X-ray Spectra as Diagnostics of Plasma Temperauure Structure" Aston. and Astroph., Vol. 49. 1976, pp. 239-250 "'Hard X-ray Bremsstrahlung Production in Solar Flares by High-energy Proton Beams" Astrophysical Journal, Vol. 295, 1985, pp. 648-653 •"Height Structure of Thermal Hard X-ray Sources on the Sun" Solar Physics. Vol. 73, 1981. pp. 121-132 ----"Implications of the Solar Flare Gamma-ray Limb-brightening Observations for Particle Acceleration and the Flare Magnetic Environment" Astron. and Astroph., Vol. 215, 1989, pp. 371-380 -"Impulsive Phase Transport" NASA CP-2439, Ch. 3. 1984 -"Interpretation of Fast Ripple Structure in Solar Impulsive Bursts" Solar Physics. Vol. 97, 1985, pp. 363-373 -----"Limits on the Streaming and Escape of Electrons in Thermal Models for Solar Hard X-ray Emissions" Astrophysical Journal, Vol. 242, 1980, pp. 799-805 "Multiple Energetic Injections in a Strong Spike-like Solar Burst" Solar Physics. Vol. 91, 1984, pp. 359-376 ----"On the Bremsstrahlung Efficiency of Nonthermal Hard X-ray Source Models" Solar Physics. Vol. 122, 1989, pp. 303-311 -"Precipitation in Trap Models for Solar Hard X-ray Bursts" Mon. Not. R. Astro. Sot., Vol. 176, 1976, pp. 15-30 "Production of a Collisionless Conduction Front by Rapid Coronal Heating and Its Role in Solar Hard X-ray Bursts" Astrophysical Journal, Vol. 228, 1979, pp. 592-597 -"Quantitative Analysis of Hard X-ray 'Footpoint' Flares Observed by the Solar Maximum Mission" Solar Physics. Vol. 99, 1985, pp. 231-262 "'Self Similar Lagrangian Hydrodynamics of Beam Heated Solar Flare Atmospheres" Astrophysical Journal. Vol. 339, 1989, pp. 1123-I131 "The Deduction of Energy Spectra of Non-thermal Electrons in Flares from the Observed Dynamic Spectra of Hard X-ray Bursts" Solar Physics, Vol. 18, 1971, pp. 489-502 "The Effect of Precipitation on Diagnostics for Electron Trap Models of Solar Hard X-ray Bursts" Astron. and Astroph., Vol. 119, 1983, pp. 297-300 "The Inter-relationship of Hard X-ray and EUV Bursts During Solar Flaes" Solar Physics,Vol. 57, 1978, pp. 175-190 "The Polorization and Directivity of Solar-flare Hard X-ray Bremsstrahlung from a Thermal Source" Astrophysical Journal. Vol. 237, 1980, pp. 1015-1023 "'Thick Target Beam Interpretation of Stereo Observations of a Solar Hard-x-ray Burst" Astrophysical Journal, Vol. 245, 1981, pp. L91-L95 Chanan, G.-"Impulsive Phase Solar Flare X-ray Polarimetry" NASA CP-2449, 1984, pp. 47-61 ---"Prospects for Solar Flare X-ray Polarimetry" Solar Physics. Vol. i18. 1988. pp. 309-319 Chandrashekar. S.-"CollisionalHeating by Nonthermal Electrons in a Tapered ),Iagnetic Loop" Solar Physics. Vol. 107, 1986, pp. 83-94 Chou. C.-"Fourier-coded Aperture Imaging inNuclear .Medicine" SPIE Vol. 4,54.1984.pp. 457-464 "Gamma-ray Imaging in Fourier Space" Optics Letters, Vol. 3. No. 5. 1978. pp. 187-189 Chupp. E. L.-"High-energy Neutral Radiations from the Sun" Ann. Re:'.Ast. and Ast.. 1984. pp. 359-387 Cook. W. R.-"A Thick Anger Camera for Gamma-ray Astronomy" lEEK Transactions. 1/'ol. NS-32, No. 1. 1985, pp. 129-133 Cornwe!l. T. J.-'A Simple .Maximum Entropy Deconvolution Algorithm" Astron. and Astroph.. Vol. 143. 1985, pp. 77-83 Craig, I. J. D .-" Fundamental Limitations of X-ray Spectra as Diagnostics of Plasma Tem- perature Structure" Astron. and Astroph., Vol. 49, 1976, pp. 239-250 Crannell. C. J.-;'A Fourier Transform Telescope for Sub-arcsecond Imaging of X-rays and Gamma-rays" SPIE Vol, 571. 1985. pp. 142-148 Cruise, A..kI.-"Aperture Synthesis in X-ray Astronomy" .Mon. Not. R. Astr. Soc., Vol. 170. 1975. pp. 305-312 Dennis, B. R.-"Solar Flare Hard X-ray Observations" Solar Physics. Vol. 118. 1988, pp. 49-94 --"Solar Hard X-ray Bursts" Solar Physics. Vol. 100. 1985, pp. 465-490 Dermer. C. D.-"Directionality of Bremsstrahlung from Relativistic Electrons in Solar Flares" Astrophysical Journal, Vol. 301, 1986, pp. 962-974 Dicke. R. H.-"Scatter-hole Cameras for X-rays and Gamma-rays" Astrophysical Journal. Vol. 153. 1968. pp. L101-L106 Doyle. J. G.-"Energetics of a Double Flare on November 8, 1980" Solar Physics. Vol. 98. 1985, pp. 141-158 Duijveman, A.-" X-ray Imaging of Three Flares During the Impulsive Phase" Solar Physics. Vol. 81, 1982, pp. 137-157 Edminston. 5[. D.-"Energy Resolution Considerations in Liquid Ionization Chambers" IEEE Transactions. Vol. NS-25, No. 1. 1978, pp. 352-353 Elvis, M-"Grazing Incidence Imaging from 10 to 40 keV" Applied Optics. Vol. 27. No. $. 1988, pp. 1481-1485 Emslie, A. G. Solar Physics, Vol. 113, 1987, pp. 175-181 -"A Comparisonof the Height Distributions of Solar Flare Hard X-rays in Thick Target andThermal Models" Astrophysical Journal. Vol. 245. 1981. pp. 711-720 -"A New Quasi-thermal Trap Model for Solar Flare Hard X-ray Bursts: An Elec- trostatic Trap Model" Astrophysical Journal, Vol. 330. 1988. pp. 997-1007 -"A Self-consistent Interpretation of the Solar Flare Extreme-ultraviolet to Hard X-ray Ratio in Large Events" Astrophysical Journal. Vol. 326. 1988. pp. 997-1001 "Adiabatic and Nonadiabatic Processes in Thermal Models of Solar Hard X-ray Bursts" Astrophysical Journal. Vol. 244. 1981, pp. 653-658 -"Analytic Limits on the Forms of Spectra Possible from Optically Thin Collisional Bremsstrahlung Source .Models" Astrophysical Journal, Vol. 331. 1988. pp. 554-564 -"Application of the Trap-plus-precipitation Hard X-ray Burst Model to the Flare of August 4, 1972" Solar Physics, Vol. 83, 1979, pp. 175-185 -"Beam return Current Systems in Nonthermal Solar Flare .Models" Solar Physics. !7ol. 120. 1989, pp. 343-349 -" Chromospheric Heating by Electron and Proton Bombardment in the Solar Flare of June 7, 1980" Solar Physics. VoI. 84. 1983, pp. 263-269 -----"Collisional Heating by Nonthermal Electrons in a Tapered Magnetic Loop" Solar Physcis, Vol. 107, 1986, pp. 83-94 "Discrepancies Between Theoretical and Empirical Models of the Flaring Solar Chromosphere and their Possible Resolution" Astrophysical Journal, Vol. 246. 1981. pp. 337-343 "Energetic Electrons as an Energy Transport Mechanism in Solar Flares" Solar Physics, Vol. 86, 1983. pp. 133-146 "Energetics of a Double Flare on November 8, 1980" Solar Physics, Vol. 98. 1985. pp. 141-158 "Energy Release in Solar Flares" Solar Physics, \:ol. 65, 1980. pp. 271-281 "Fast Transients in Hard X-ray Solar Flares" Solar Physics, Vol. 86. 1983, pp. 239-240 "Gamma-ray, Neutron, and Hard X-ray Studies and Requirements for a High- energy Solar Physics Facility" Solar Physics, Vol. 118, 1988, pp. 17-46 "Gas Dynamics in the Impulsive Phase of Solar Flares. I. Thick-target Heating by Nonthermal Electrons" Astrophysical 3ournal, Vol. 279, 1984. pp. 896-908 -"Gas Dynamics in the Impulsive Phase of Solar Flares. II. The Structure of the Transition Region - A Diagnostic of Energy Transport Processes" Astrophysical 3ournal. \,'ol. 288, 1988, pp. 779-788 "Hard X-ray Bremsstrahlung Production in Solar Flares by High-energy Proton Beams" Astrophysical Journal, \,'ol. 295, 1985, pp. 648-653 "Hard X-ray Emission in Electron-heated Solar Flares - A Comparison of Nonther- mal and Thermal Contributions" Solar Physics, Vol. I10, 1987, pp. 30>315 ."Impulsive Phase Solar Flare X-ray Polarimetry" NASA CP-2449, 1984, pp. 27-61