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The solar flare proton rigidity spectra for several flares occurring between 1967 and 1972 have been deduced from the ground level cosmic ray neutron monitor observations. To obtain consistent agreement for all the ground level events (GLEs) analyzed, the specific yield functions of Lockwood and Webber (1967) must be reduced slightly below P = 1.6 GV. The typical spectral indices of solar cosmic rays deduced for GLEs vary from 4 to 6 if the differential spectrum is represented by KP to the minus gamma power. Only occasionally is the spectrum as steep as 8 or 9. The observed spectral index is independent of the magnitude of the integral solar proton flux above 1 GV.

Observations of global radiation received in a small catchment in Yorkshire were analysed for clear sky conditions and an empirical relationship of the form Q = 1380 sin θ(a + b sin θ) W m−2 Found, between incoming solar radiation Q and the solar elevation θ, where a and b are constants. The constants differ markedly from those obtained in a similar analysis of data from eastern Atlantic weather ships, suggesting that the radiation, under cloudless skies, over inland Britain, is only about 60% of that received under cloudless skies over the eastern Atlantic.

On January 28, 1967, at 0830 UT, sea-level neutron monitors at cutoff rigidities Pc ≤ 4.5 Gv recorded an increase presumably associated with a solar flare. From geophysical data and the characteristics of the cosmic-ray increase at earth, it is concluded that this increase was produced by a solar flare located about 60° beyond the west limb of the sun. The primary rigidity spectrum in the rigidity interval 1.5 < P

The objective of this experiment is to monitor the cosmic-ray neutron flux over a large region of space near the earth for an extended time with a simple neutron monitor. The basic detecting system to measure the integrated neutron flux from 10-8 to 15 MeV consists of a moderated He3 proportional counter surrounded by a charged-particle rejection system. A plastic scintillator viewed by a photomultiplier is operated in coincidence with the neutron counter to determine the energy spectrum and flux in the 1-10 MeV range. In order to minimize contributions from neutrons produced within the OGO spacecraft, the sensor is located about 4.5 meters out on the EP-5 boom. The experiment includes an in-flight calibrator to check pulse discriminator levels on neutron and charged-particle channels and a calibration-loop system to compensate for changes in the photo-multiplier gain. The mean neutron detection efficiency for the expected neutron energy spectrum over the energy range 10-8-15 MeV is 1.8 cm2. The weight of the neutron sensor is 2.58 kg, with a length of 0.314 meter and a diameter of 0.111 meters. The total power requirements are 4.5 watts.

The variation in the cosmic-ray intensity recorded by neutron monitors from 1958 to 1965 has been investigated to deduce the form of the solar modulation of the cosmic radiation. The neutron monitor data were carefully selected and examined. The observed quarter-year average changes in the intensity at the neutron-monitor stations were then compared with the calculated changes using different modulation functions. Finally, the observed variations in the intensities recorded by neutron monitors were compared with the variations of the radiation observed at the top of the atmosphere and in space. The change in both the neutron monitor intensity and the primary cosmic-radiation can be described by a modulation of the form exp(−K/P) in the rigidity range 0.5 < P < 50 Gv.

Forbush decreases vertical cutoff rigidity dependence, comparing cosmic ray intensities from Pioneer 8 detector and ground based neutron monitors

The cosmic-ray neutron intensity at a large number of stations was analyzed to determine the differences in onset times of the large Forbush decreases occurring from 1957 to 1961. From the directional response characteristics of the neutron detectors, these differences in onset tinies are related to directions in space beyond the geomagnetic field. It is observed that the onset of the Forbush decrease was always earlier from west of the earth-sun line, regardless of the location on the sun of the solar flare, which was the source of the plasma cloud causing the decrease. The onset differences from the directions west and east of the earth-sun line varied from the order of minutes to a few hours. For Forbush decreases whose onset at some stations occurred before the sudden commencement of a magnetic storm, the solar plasma cloud responsible for the decrease generally originated from the western hemisphere of the solar disk. The stations recording the earlier decrease were, in general, sampling particles from west of the earth-sun line at the time of the decrease. These results are explained in terms of the configuration of the solar plasma cloud, and conclusions are drawn about the plasma velocity and the magnitudemore » of the associated magnetic field. (auth)« less

A method is presented whereby the pressure variations at any point in the field of a baffled piston may be efficiently calculated. If a solution for the impulse response of a piston of a given geometry is known, then for harmonic excitation the steady‐state field may be computed by evaluating the driving‐frequency component of the Fourier transform of the impulse response. This method involves a single integration, whereas the direct numerical solution requires a double numerical integration. An exact, closed‐form solution for the impulse response of a rectangular piston is derived. With this solution and the known solution for the impulse response of a circular piston the steady‐state solutions for these two geometries are obtained. Three‐dimensional and contour plots of data obtained for a circular piston and for a plane of symmetry of a rectangular piston field are presented. The plots for the circular piston compare favorably with previously published plots of data calculated by a double integration.

A pulse shape discrimination syste the following characteristicsm high nultiparticle resolution ( M ≈3), wide dynamic range (1 E n 50kHz), built-in calibration, minimum weight (

Observations of the cosmic radiation arriving at the earth show that both the energy spectrum and total intensity of particles change with time. A brief survey is presented of the major changes in the flux of relativistic particles, with representative data from nucleonic detectors. The rigidity dependence and attenuation for the long-term change and transient variations are discussed. Some data for the sudden increases which represent solar injection are shown. The investigation of these intensity-time variations yields information about the electromagnetic state of the earth-sun region.

Measurement of the cosmic-ray neutron leakage flux and energy spectrum in the range 1 to 10 MeV by a neutron detector on the Ogo 6 satellite from June 7 to Sept. 30, 1969. The same detector simultaneously measured the total leakage flux, having 75% of its response to the leakage flux in the interval from 1 keV to 1 MeV. For a neutron energy spectrum of the form AE to the minus gamma in the range from 1 to 10 MeV, the upper limit to gamma for polar regions was found to be 1.0 and for the equatorial regions was 1.2. For the polar regions, the lower limit to gamma was found to be 0.8. This energy spectrum at 1 to 10 MeV is slightly flatter than Newkirk (1963) predicted.

Intensity increases or decreases, which are sometimes a strong function of longitude, are frequently found superimposed on the normal behavior of the cosmic-ray intensity during Forbush decreases. A study has been made of these effects utilizing the neutron monitor data from many stations distributed in latitude and longitude. The anisotropies recorded as decreased intensities occurred from the west, and those recorded as increases occurred from the east, of the earth-sun line. These anisotropies were both long and short lived. The long-lived anisotropies shifted westward as time progressed. Besides the anisotropies, superimposed intensity increases occurred at all stations at the same universal time, the magnitudes of which were larger at stations sampling particles from directions east of the earth-sun line at the time of the increase. A qualitative explanation of these observed effects is given in terms of the configuration and the possible instabilities of the plasma cloud.

Two increases of about 100% in the cosmic-ray nucleonic intensity were recorded at Mount Washington and Durham, New Hampshire, on November 12 and 15 following large solar flares. A third small increase was observed on November 20. The two large increases exhibited different features, and these differences are discussed in relation to solar phenomena. From a study of the worldwide nucleonic intensity data it is found that the rigidity spectrum can be expressed as KP/sup -n/, with n = 6 for both flares; for the increase on November 12, there is particle dispersion, and an approximate evaluation of the diffusion has been made; the classical impact-zone theory does not apply for these flares, evidence being presented for the existence of magnetic fields and some scattering effects between the earth and the sun. (auth)

The monthly mean intensity of the nucleonic component of cosmic radiation measured at Mt. Washington, geographic latitude 44.2\ifmmode^\circ\else\textdegree\fi{}N and elevation 6262 ft, decreased 22% from July, 1954 to December, 1957. The decreased intensity now prevailing came about through a series of sudden decreases from which only partial recovery occurred. During this same period, the amplitude of the day-to-day intensity changes has increased. A study has been made of the largest Forbush-type decreases which have occurred in this interval. Many of these intensity drops have a decrease rate \ensuremath{\sim}1.5% ${\mathrm{hr}}^{\ensuremath{-}1}$, with a maximum rate of 2.5% ${\mathrm{hr}}^{\ensuremath{-}1}$. In some cases they are preceded by a slight increase of \ensuremath{\sim}1.5%. These decreases do not have a similar time dependence. There is no apparent 27-day recurrent tendency for these sudden drops. The energy dependency of these events is variable. The restrictions which these decreases impose upon the existing models of solar modulation mechanisms are discussed.

The experimental measurements of the neutron flux and energy spectrum in space since 1964 are reviewed and related to the theoretical predictions. A discussion of the neutron sources is presented. The difficulties associated with neutron measurements of both the atmospheric neutron leakage flux and solar neutrons are included. Particular emphasis is placed upon the neutron leakage flux and energy measurements at energies greater than about 1 MeV. The possibilities of CRAND as a source for the energetic trapped protons are discussed in light of recent measurements of the 10–100 MeV neutron flux. The current status of the solar neutron flux observations is also presented.

Forbush decrease recorded on 26-27 January 1968 showing large anisotropies in cosmic ray flux after SC magnetic storm

Neglect of the ‘codices deteriores’ has caused the ascription of a considerable number of readings in Cic. De Diuin. to the conjectures of scholars of the fifteenth, sixteenth, and later centuries, though manuscript evidence, in some cases of a much earlier date, is to be found. Even if the presence of such readings in the manuscripts is due to conjecture and to no other cause, credit for priority should be given to the manuscripts. The following notes are restricted to the evidence of the London MSS.

An experiment to measure the earth's neutron albedo was flown on three polar orbiting Agena satellites in 1962. The detector, a BF3 counter within a moderator, was surrounded by a ring of charged-particle proportional counters to discriminate against neutrons produced by protons in the detector assembly. The results show an albedo flux of 0.085±0.03 n/cm2 sec at the equator at 300-km altitude, in agreement with the rocket measurements of Bame et al. and the calculations of Lingenfelter. However, at high latitudes we find 0.24±0.06 n/cm2 sec, a factor of 4 below the calculations of Lingenfelter. The appendix outlines calculations that have been used to estimate the neutron production by primary cosmic-ray protons on the detector assembly and the vehicle itself. These calculations are compared with the experimental measurements of production in the detector assembly.

The atmospheric neutron leakage rate in the energy range from 0.01 to 10,000,000 eV has been measured as a function of latitude, altitude, and time with a neutron detector on board the Ogo 6 satellite. The latitude dependence of the neutron leakage is in reasonable agreement with that predicted by Lingenfelter (1963) and Light et al. (1973) if the neutron energy spectrum has the shape calculated by Newkirk (1963). The change in the neutron latitude dependence with the cosmic ray modulation agrees with the predictions of Lingenfelter and Light et al. For several solar proton events enhancements were observed in the neutron counting rates at lambda greater than or equal to 70 deg. Such events, however, provide an insignificant injection of protons at E less than or equal to 20 MeV into the radiation belts. An isotropic angular distribution of the neutron leakage in the energy range from 0.1 keV to 10 MeV best fits the observed altitude dependence of the neutron leakage flux.

From the recent neutron monitor latitude survey by H. Carmichael and from the primary spectrum measurements by W. Webber both at solar minimum, we have deduced new differential response and specific yield functions of cosmic-ray neutron monitors located at sea level and mountain elevations with vertical cutoff rigidities in the interval 0.7 < Pc < 10 Gv. The differential response functions at sea level are larger than the previously calculated values at rigidities P < 3 Gv. The proton specific yield function at sea level is obtained and can be represented by KP+2.6 for 2.5 < P < 6 Gv. The relative contributions of primary nuclei with Z ≥ 2 to the counting rate of a sea-level neutron monitor as a function of Pc are evaluated. The change in the differential response functions between 1963 and 1965 has been used to determine the change in the primary differential cosmic-ray spectrum. The decrease in the observed differential primary spectrum agrees well with the decrease in the neutron differential response function in the rigidity range where they can be compared.

The functional form of the modulation for the 11-year variation changed abruptly after the Forbush decrease of June 8, 1969. This change in the 11-year modulation suggests that this Forbush decrease was an integral part of the 11-year variation. Some details of the change as observed by neutron monitors and by spacecraft at low energies are discussed.

The unique features of this instrument are the following: 1. The charged particle shield (NE 102) uses only two P. M. tubes. 2. The 4? charged particle shield encloses completely the neutron-gamma detector, all P. M. tubes and associated sensor electronics. 3. The pulse shape discriminator (P. S. D.) is passive and miniature, with "M" > 3.1 at the Co60 Compton edge. 4. The separate spectra of neutrons (1 < En < 20 Mev) and gammas (1 < E? < 7 Mev) are extracted. 5. The I. F. C. (4% resolution) with P. S. D. on NaI(Tl & Am241) is also displayed with (4). 6. The quality of data is checked by parity bits, and data are transmitted by a parallel, redundant FM-FM TM system.

Cosmic ray albedo neutron flux latitude and altitude dependence, using OGO-6 polar orbiting satellite

Cosmic ray neutron integrated flux measurements up to 350 km for energies to 15 Mev, determining neutron leakage flux

The diffusion equation for the temperature distribution in each of k sections of a hollow laminated composite cylinder with a circumferentially varying external heat flux is solved. The composite consists of k discrete cylinders each of a different material with perfect thermal contact at each of the k-1 interfaces. The cylinders have an arbitrary initial temperature distribution and the temperature on the inside surface of the composite is an arbitrary function of time. The solution is obtained by using a Fourier integral transformation and a dependent variable substitution. This produces a new partial differential equation with homogeneous boundary conditions. This new equation is then solved by using a type of orthogonality relationship developed by Vodicka.

SUMMARY: The germination process of spores of several fungi which require exogenous energy-sources was initiated in non-amended natural soil, a medium deficient in energy-yielding substrates. As measured by subsequent germination time on sterilized soil, this phase accounted for about 8 to 25% of the total germination time. In conidia of Penicillium frequentans it was irreversible, was inhibited by temperatures of 1°C and was dependent on water alone. Continued progress towards germ-tube formation required exogenous energy-yielding nutrients. When incubation on sterilized soil was interrupted by exposure to non-amended natural soil or a model system designed to imitate the microbial energy-source sink of natural soil, progress towards germination ceased in several fungi. Progress already made towards germination was maintained if the exposure to deprived conditions was short (about 3 days or less), but if longer the germination process reverted towards the water-dependent phase. The reversal, in P. frequentans conidia, paralleled the loss of 14C from spores labelled with [14C]glucose. When 14C-labelled conidia were incubated in an artificial nutrient sink, the label lost was about equally divided between 14CO2 and non-gaseous 14C-labelled metabolites. Pretreatment of P. frequentans conidia in water stimulated uptake of [14C]glucose. The results support the view that soil fungistasis in many instances is caused by nutrient deprivation.

An experimental and theoretical investigation is presented of farfield distortion of a finite‐amplitude wave generated by a circular‐piston source. Nearfield distortion is neglected. Thus the boundary condition is that the acoustic signal at the beginning of the farfield is a pure sine wave of amplitude proportional to the small‐signal directivity factor for the piston. The method of applying weak‐shock theory to obtain directivity patterns and propagation curves is outlined. A criterion for the maximum range at which weak‐shock theory is valid is derived for each harmonic. An ad hoc method of matching at this range the small‐signal solution, with absorption included, to the weak‐shock solution is proposed. Data obtained for a fundamental frequency of 450 kHz and source levels of 109 and 127 dB (re 1 μbar at 1 yd) are presented. Theoretical and experimental beam patterns are in good agreement. Propagation data presented for the 127‐dB source level are in poor agreement with the predictions of unmodified w...

An analysis has been made of the large and rapid Forbush decreases in the cosmic radiation which occurred from 1954 to 1959. Data from the IGY network of cosmic-ray stations have been utilized to determine the changes in the primary rigidity spectrum, any significant differences in the onset times, and the existence of anisotropies during the decreases. To evaluate changes in the primary spectrum during a decrease it is necessary to know the spectrum before the event. It has been found that this long-term variation is adequately described by a modulation of the primary spectrum given by 1-C(t)P−1, where 1≤C(t)≤2.5 and C(t) is a function of time in the solar activity cycle. For individual decreases the modulation is 1-{C(tF)P−1+kF}, where 0≤kF≤4 per cent for nucleonic detectors at sea level and mountain elevations and 0.6≤C(tF≤2.2. No systematic variations of the onset times were evident, except for the smaller decreases where the effect of any superimposed daily variation is important. The primary radiation remained isotropic during the large decreases. These events were preceded within 3 hours by a sudden commencement geomagnetic storm. These results are discussed in terms of possible solar-modulating mechanisms.

The upper limit on the quiet time solar neutron flux from 1–20 MeV has been measured to be less than 2 × 10-3n cm-2 s−1 at the 95% confidence level. This result is deduced from the OGO-6 neutron detector measurements of the ‘day-night’ effect near the equator at low altitudes for the period from June 7, 1969, to December 23, 1969. The OGO-6 detector had very low (< 4%) counting rate contributions from locally produced neutrons in the detecting system and the spacecraft and from charged-particle interactions in the neutron sensor.

DDT was rapidly converted to DDD in submerged soil amended with alfalfa residue. The rate of conversion increased with increasing amounts of alfalfa. In nutrient media, 2 of 10 bacteria and 2 of 10 actinomycetes were completely inhibited by 10 p.p.m. DDT, whereas 4 of 10 bacteria and 6 of 10 actinomycetes were inhibited by 10 p.p.m. DDD. When added to agar in soil dilution plates, 10 p.p.m. DDT or DDD markedly decreased numbers of bacterial and actinomycete colonies. DDD had a broader antimicrobial spectrum and greater toxicity to microorganisms than DDT. However, both compounds had little effect on microorganisms in soil. Fungi were not affected by either compound in culture or in soil.

An analysis has been made of the cosmic-ray data recorded by the IGY network of stations during the sudden decrease of intensity on February 11, 1958. The unusual rapidity of the decrease, which was followed by a temporary recovery, provides a critical test for existing solar-controlled modulating mechanisms. The main decrease, occurring practically simultaneously over the earth, was relatively energy-insensitive. The subsequent temporary recovery appeared to be associated with a spatial anisotropy. It is suggested that these variations can be interpreted as the result of disordering the outer geomagnetic field by the solar wind, as first pointed out by Parker.

In the opening chapter of the Iudicium de Dinarcho Dionysius quotes a passage from the Περì ὁμωνὐμων of Demetrius Magnes, mat the end of which come the words ἧ δέ λὲξις ἐςτί τοῦ Δεινάρχου κυρὶως ἠθική πάθος κινοῦσα σχεδòν τῇ πικρíᾳ μóνον καì τῷ τóνῶ τοὖ Δημοσθθενικοὖ χαρακτῆρος λειπομὲνη τοῦ δέ πιθανοὖ καì κυρíιυ μηδὲν ἐνδέονσα. [I have deliberately omitted all punctuation marks, because the punctuation of this sentence is still doubtful, though I hope to suggest a possible interpretation of its meaning at the end of this article.] Now there is nothing in this sentence or in the words preceding it to indicate beyond all possibility of doubt the precise meaning ofκυρíως ἠθικὴ. And in such circumstances, to allow free play to personal (or perhaps natural) prejudices regarding the significance of thephrase is more than dangerous. The whole problem of ἠθική λὲξις has been treated too cursorily. If one mentions the phrase to a non-professional student of Greek, who, however, has some acquaintance with the Attic orators, he immediately replies: ‘I suppose you mean the sort of thing you meet in Lysias.’ And he is to beexcused, because, after all, that is the predominant meaning of the term. But it has other senses, and therefore one must fight shy of vague statements like that of Finke, who, after quoting the above lines, comment: ‘Demetrius Magnus attribuit ei (sc. Dinarcho)τἡν κυρíαν λὲξιν qua non sit Demosthene inferior’(the last few words of which are possibly not even a correct translation of the text); or of Burgess, who enumerates qualities, ideas, and topics ‘of special value to the epideictic and court orators, ’ among which appears ἠθοποιἷα which he merely translates ‘impersonation or delineation of character, ’ without offering any further comment. Sandys talks of ‘the ethical warmth of colouring, by which the dullest details are lit up with a fresh life and interest.’ Gromska is even more vague (and seems almost to confuse ἦθ∨ς and χαρακτὴρ: ‘Grammatici antiqui, qui de Hyperide tractabant, de eloquentiae eius genere disputabant, orationum Hyperidearum compositionem et ἦθ∨ς respicientes, i.e. quantum in arte rhetorica et oratoria valeret, examinantes.’ In the hope, therefore, of being able to represent the difficulty inherent in these lines, and of attempting to remove it, or at any rate to shed a broader beam of light upon it than has been shed hitherto, I propose to review very briefly the fluctuations of meaning in the life of this phrase and its equivalents, as we find them used in the critical writings of the Greek philosophers and rhetoricians.

A series of balloon-borne soundings in the atmosphere with single Geiger tubes was made during the period January to September, 1958. The counting rate determined at the Pfotzer maximum is compared with that recorded by the nucleonic detector at Mt. Washington (1909 m; lambda = 55-N). Large changes in the counting rate of each detector were observed, and the ratio of these changes is approximately 2: 1. Several large deviations from this normal ratio were also observed. These deviations occur for flights on which the shape of the intensity- altitude curve near the Pfotzer maxmum is quite different from the normal. These changes are explained in terms of either depressions of the lowenergy portion of the cosmic-ray spectrum following marked decreases in the nucleonic component, or the presence of excess low-energy radiation. An anomalous increase of approximately 100% was observed at high altitudes during one flight and was attributed to high-energy x radiation. It is found that the hemispherical average unidirectional intensity above the atmosphere derived from the counting rate at the Pfotzer maximum has decreased approximately 200% from 1954 to 1958 at lambda = 53-N, and this change is compared with results at other latitudes. (auth)

The variation in the cosmic-ray intensity recorded by neutron monitors from 1958 to 1965 has been investigated to deduce the form of the solar modulation of the cosmic radiation. The observed changes in the intensity at the neutron monitor stations, averaged over quarter-year periods, were compared with changes calculated using modulation functions depending upon energy, rigidity, and velocity × rigidity. These calculations were based upon the revised differential response functions deduced by Lockwood and Webber (1967). The variance between the observed and calculated changes in the neutron monitor intensities at different stations was minimized to determine the best form of the solar modulation function. We find that the change of the primary cosmic radiation, deduced from the change in the neutron monitor intensity as well as from direct measurements of the primary flux, can be described by a modulation of the form exp(–K/P) in the rigidity range 0.5

The method of approach to detailed criticism of prose-writers and poets adopted by Dionysius is in a large measure comparative. The procedure of comparison is threefold: firstly, the bringing together of passages from authors to elicit points of resemblance or of difference between their styles secondly, the assumption of the existence of common critical standards for all works of art, whether literature, painting, or sculpture thirdly, the use of metaphor and simile to illustrate matters of criticism which need the assistance of some visual or mental image to make clear the exact meaning of the point of criticism. The metaphorical vocabulary is the richer for the greater preoccupation of Dionysius with aesthetic appreciation than with philosophical analysis; and any seeming differences in technical vocabulary are compensated by the freedom with which his vocabulary in general draws on the Greek of his own and earlier times. The following list gives some of the more interesting metaphorical expressions used in the rhetorical works, with notes on their meaning and, in some cases, with illustrations of the use of the same or similar terms in other Greek critics and in the volumes of scholia.

The results of an experimental study of the temperature dependence of commercial BF3 neutron counters are reported. The arrangement used for this investigation is described and the results analyzed. The conclusion is reached that during a given pulse there is an increase in the number of negative ions formed by electron attachment with an increase in temperature of the tube. This effect is an equilibrium process. Upon reduction of the tube temperature the tube characteristics return to their original values. The consequence of this temperature dependence on the resultant counting rate is discussed.