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At least 379 records · Page 21

Fungi of Mount Babia Gora. 3: The indicating value of macromycetes in the forest associations

The results of a mycological investigation of the forests of the upper mountain forest zone of Mt. Babia Gora and the synthetic characteristics of participation of macromycetes in all the forests studied are presented. Regularities and distinct connections were found in the occurrence of macromycetes on the background of various forest associations, differences in exposure, orography, climate, and changes induced by man.

Bujakiewicz, A.↗

New atmospheric sensor analysis study

A progress report of the activities pertaining to the Atmospheric Sensor Analysis Study is given. The current revision of the Perkin-Elmer Operating System OS/32 MT 7.2.1 was installed on the Atmospheric Modeling and Simulation System (AMASS). This software appears to offer a means of distributing disc storage among the user community in a more optimal manner than previously available using the file manager. Next Generation Weather Radar (NEXRAD) software has been received from the National Severe Storms Laboratory (NSSL) and has been loaded onto the Perkin-Elmer. Extensive modifications will be required to permit the software to be compatible with the operating system.

Parker, K. G.↗

The Magneto-optical Filter, Working Principles and Recent Progress

The Magneto-Optical Filter is described which allows simultaneous magnetic and velocity measurements (in both imaging and non-imaging modes) without the need for a spectrograph. In this way the stability and alignment problems of the spectrograph are completely overcome. Its major advantages are: wavelength absolute reference and stability, high signal to noise ratio and independence of the transmission profile from the incidence angle of the solar beam. It is an imaging instrument allowing high wave number analysis in the solar oscillation spectrum and a continuous monitoring of the image position through the chromospheric facular structures. The apparatus in use at Mt. Wilson is assembled in a modular form. The most important part of it is a glass cell containing the sodium vapor. The filter is easy to use but the cell is not easy to construct in an optimal way. The technology is in progress both to use Na and K together and to prevent the windows from becoming coated during a long-term operation.

Cacciani, A.↗

Evaluation of a Magneto-optical Filter and a Fabry-perot Interferometer for the Measurement of Solar Velocity Fields from Space

A program was developed to evaluate the performance of three different devices as possible space-borne solar velocity field imagers. Two of these three devices, a magneto-optical filter and a molecular adherence Fabry-Perot interferometer were installed in a newly-constructed observing system located at the 60-foot tower telescope at the Mt. Wilson Observatory. Time series of solar filtergrams and Dopplergrams lasting up to 10 hours per day were obtained with the filter while shorter runs were obtained with the Fabry-Perot. Two-dimensional k (sub h)-omega power spectra which show clearly the well-known p-mode ridges were computed from the time series obtained with the magneto-optical filter. These power spectra were compared with similar power spectra obtained recently with the 13.7-m McMath spectrograph at Kitt Peak.

Rhodes, E. J., Jr.↗

Data analysis for lidar and quartz crystal microbalance systems

Results are presented of the analysis of data taken on the stratospheric aerosol, using lidar, Quartz Crystal Microbalance (QCM), and the SAGE and SAM II satellite systems. The main objective of the work reported has been to use the data, taken with the NASA-LaRC instruments to study the stratospheric effects of volcanic eruptions during the period between the launch of the SAGE and SAM II satellite systems and October 1980. Four significant volcanic eruptions, for which data are available, occurred during this period--Soufriere, Sierra Negra, Mt. St. Helens, and Ulawun. Data on these have been analyzed to determine the changes in stratospheric mass loading produced by the eruptions, and to study the dispersion of the newly injected material.

Kent, G. S.↗

Composition of primary cosmic rays at energies 10(15) to approximately 10(16) eV

The sigma epsilon gamma spectrum in 1 approx. 5 x 1000 TV observed at Mt. Fuji suggests that the flux of primary protons 10 to the 15 approx 10th eV is lower by a factor of 2 approx. 3 than a simple extrapolation from lower energies; the integral proton spectrum tends to be steeper than around to the power V and the spectral index tends to be steeper than Epsilon to the -17th power around 10 to the 14th power eV and the spectral index becomes approx. 2.0 around 10 to the 15th power eV. If the total flux of primary particles has no steepening up to approx 10 to the 15th power eV, than the fraction of primary protons to the total flux should be approx 20% in contrast to approx 45% at lower energies.

Amenomori, M.↗

Cosmic ray intensity and the tilt of the neutral sheet

Recent publications have related long-term variations in cosmic ray intensity at the Earth with long term variations in the tilt of the neutral sheet in the inner heliosphere. The tilt of the neutral sheet from 1971 to 1974 is compared with the cosmic ray intensity at Earth, recorded by the Mt. Washington neutron monitor. The remarkable large decreases in cosmic ray intensity which occurred in 1973 and 1974 correlate well with excursions in the tilt of the neutral sheet which occurred earlier during these same two years.

Saito, T.↗

Cerenkov light images of EAS produced by primary gamma

It is shown that it should be possible to distinguish very effectively between background hadronic showers and TeV gamma ray showers from a point source on the basis of the width, length and orientation of the Cerenkov light images of the shower, seen in the focal plane of a focusing mirror, even with a relatively coarse pixel size such as employed in the Mt. Hopkins detector. Predictions of the response of this system to air showers are presented.

Hillas, A. M.↗

Note on the detection of high energy primary cosmic gamma rays by air shower observation

A mountain altitude experiment is planned at Mt. Norikura in Japan to search for point sources of astrophysical high-energy gamma rays in the 10 to the 15th power eV range. The advantages of mountain level observation of IR showers is stressed, especially in the case of high-energy gamma primaries from Cygnus X3 and other similar point sources.

Kasahara, K.↗

Intensities of high-energy cosmic rays at Mount Kanbala

The energy spectra of atmospheric cosmic rays at Mt. Kanbala (520 g/sq cm.) are measured with emulsion chambers. The power indexes of the spectra are values of about 2.0 for both gamma-rays and hadrons. Those fluxes are consistent with the ones expected from the model of primary cosmic rays with heavy nuclei of high content in the energy around 10 to the 15th power eV.

Ren, J. R.↗

High energy gamma-rays and hadrons at Mount Fuji

The energy spectra of high energy gamma-rays and hadrons were obtained by the emulsion chamber with 40 c.u. thickness at Mt. Fuji (3750 m). These results are compared with the Monte Carlo calculation based on the same model which is used in a family analysis. Our data are compatible with the model of heavy-enriched primary and scaling in the fragmentation region.

Amenomori, M.↗

A cosmic ray super high multicore family event. 1: Experiment and general features

Information on the fragmentation region in super high energy hadronic interactions can be obtained through the observations of gamma-ray families produced by cosmic rays. Gamma-ray families with the sum of E sub gamma or 1000 TeV are receiving increasing interests in emulsion chamber experiments. There exist some complications caused by the superposition of nuclear and electromagnetic cascades and the uncertainty in the nature of the primary particles. These complications usually make the conclusions drawn from various interesting phenomena observed in family events not so definite. An interesting family event KO E19, which is likely to have suffered only very slight disturbances is described. It was found in the Mt. Kambala emulsion chamber experiment. The production height of the event is determined to be H=(70 + or - 30)m and some conclusions are given.

Ren, J. R.↗

A cosmic ray super high energy multicore family event. 2: Structure and fragmentation characteristics of the jets

Quarks and gluons are not directly observable, but may be displayed through fragmentation in the form of hadronic jets, the evidence of which was first revealed in cosmic ray interactions before the advent of the modern theory of strong interactions. Experimental results from ISR and SPPS collider rendered the jet phenomena more confident and definite. All the properties of jets observed up to now at ISR and SPPS collider are in agreement with the predictions of QCD. In order to make further test of QCD in still higher energy regions, detailed study of super high energy jet events in cosmic rays is very desirable. The event KO E19 observed in the Mt. Kambala emulsion chamber is an interesting event for such study. The general features of KO E19 is described. Its total visible energy is sigma E sub gamma = 1537 TeV(E sub min = 1.5 TeV) and production height H=(70 + or - 30)m, with a hadron as its primary particle. Besides about forty small clusters, there are five super high energy cores or jets, one lying near the center of the event while the other four surrounding it, having incident directions making small angles with that of the primary particle. Detailed analysis is done on the emulsion plates inserted in the chamber, making full use of their fine granularity, superior in detecting and analyzing jet events, specially their substructures.

Source record↗

Observation of super high energy big family with large scale Fe emulsion chambers

In order to get higher efficiencies for detecting hadrons and to make technical improvements in the chamber structure, the Mt. Kambala Emulsion Chamber Collaboration constructed 57 sq. m. of Fe chamber, with thickness 29 c.u.(1c.u.=17.6 mm Fe), using 300 tons of Fe plates and made the first exposure from Sept., 1982 to May, 1984. The photosensitive layers consist of X-ray films of Sakura N type, Fuji No. 100 type and Tianjin III type, some of them contain also emulsion plates of Fuji ET7B type. They are inserted between the Fe plates at 2 c.u., beginning at 5 c.u. from the chamber top. In a number of blocks, 3 mm spacings are provided at every 2 c.u. of Fe plates to facilitate the replacement of photosensitive layers, without disassembling the chamber. On the bottom of the chamber Fe plates of thickness 9 mm are placed in order to shield the chamber from the radioactivities of the ground. An event, numbered K2 58 of visible energy sigma E sub gamma = 7345 TeV was found in this exposure. No obvious halo is seen in the event and all the showers are clearly separated and easy to measure. A brief report of the preliminary results is presented.

Source record↗

Intensities of high-energy cosmic rays at Mount Kanbala

General features of family events with Summary E sub gamma 200 TeV, observed by the emulsion chambers at Mt. Kanbala, are presented in comparison with the Monte Carlo simulation. The lateral and cluster structure, and the energy spectra of constituent gamma-rays and hadrons are shown to be consistent with the Monte Carlo results calculated under the assumption of heavy-enriched primary, scaling, QCD jets and increasing cross-section.

Ren, J. R.↗

Fast scintillation counter system and performance

An experimental study of the fast scintillation counter (FS) system to observe a shower disk structure at Mt. Norikura is described, especially the system performance and a pulse wave-form by a single charge particles. The photomultiplier tube (PT) pulse appears at the leading edge of the main pulse. To remove this PT-pulse from the main pulse, the frame of the scintillator vessel was changed. The fast triggering system was made to decrease the dead time which came from the use of the function of the self triggering of the storage oscilloscope (OSC). To provide a new field on the multi-parameter study of the cosmic ray showers, the system response of the FS system also improved as a result of many considerations.

Sasaki, H.↗

Detection threshold energy of high energy cascade showers using thermoluminescence PTFE-sheet and hot-gas reader

A new thermoluminescence (TL) sheet was developed as a detector for high energy components in air showers. For the investigation of detection threshold energy for a cascade showeer, TL sheets were exposed at Mt. Fuji with X ray films in emulsion chambers and were scanned by a hot-gas reader. It is concluded that if a gamma ray whose energy is more than 6 TeV enters vertically into lead chambers, the resulting cascade shower is readily detectable at maximum development.

Kino, S.↗