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731.
The first 8.5m infrared heterodyne spectrometer has been constructed using tuneable semiconductor (PbSe) diode lasers and was used to measure absorption line profiles of N2O in the laboratory and black body emission from the Moon and from Mars. Spectral information was recorded over a 200 MHz bandwidth using an 8-channel filter bank. The resolution was 25 MHz (6 × 10–6
m) and the minimum detectable (black-body) power was 1 × 10–16 W for 8 min of integration. The results demonstrate the usefulness of heterodyne spectroscopy for the study of remote and local sources in the infrared.We wish to thank Dr Jack Butler and Craig Simpson (Arthur D. Little, Inc.) for their continuing (and successful) efforts to grow better diode lasers during the course of this experiment. We thank the National Radio Astronomy Observatory for the loan of a 40-channel filter bank and associated mini-computer.We thank en masse the dozens of people who loaned equipment to us for the duration of this experiment, and the commercial firms (especially Harshaw, Inc.) which expedited orders for crucial equipment. We thank Dr Bertram Donn, Dr Norman Ness, and Dr George Pieper for administrative, scientific, and financial support; and we thank Mr James Faris for technical assistance and Dr Sol Glicker for preparation of sample gas cells. We thank Dr Thomas Clark for providing the Kohoutek ephemeris, sighting printout, and predicted molecular line positions and for advice and the loan of some equipment. Finally, we wish to acknowledge the strong support accorded us by our wives and families who scarcely saw us during this period. 相似文献
732.
B.T. Tsurutani R.M. Thorne 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):439-444
A critical appraisal is made of the hypothesis that power-line harmonic radiation can influence the Earth's radiation belts by triggering intense magnetospheric emissions which in turn resonantly scatter trapped electrons into the atmospheric loss cone. While such triggering may indeed occur, a combination of theoretical arguments supplemented by an indepth analysis of OGO-5 satellite data is employed to show that triggered waves comprise at best a small fraction of the total magnetospheric wave population. Previous claims to the contrary have been either based on erroneous statistical arguments or biased by the limited sample of ducted waves detectable by ground based receivers. The totality of satellite data is consistent with a predominantly natural origin for the two classes of electromagnetic waves (chorus and plasmaspheric hiss) which are known to interact strongly with energetic radiation belt electrons. 相似文献
733.
B. Kirov K. Georgieva E. Apostolov M. Gusheva I. Kutiev S. Chapkunov Yu. Simeonova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(7):89-92
A Retarding Potential Analyzer (RPA) is designed using a micro-channel plate in front of the collector as a flow amplifier, which makes it possible to detect ion species with very low concentration (<0,5 cm.?3). A technique is described for using the micro-channel plate at abnormally high pressure (>0.01 N/m2). This allows the precise determination of the mass composition of the low ionosphere. An adaptive retarding potential consisting of 2048 steps is used to increase the sensitivity. This retarding potential is applied in the range where dI/dU ≠ 0. The sensor is hermetically sealed and opens on command. 相似文献
734.
A. Urban K.M. Torkar J. Bjordal J.A˚. Lundblad F. Søraas B. Grandal L.G. Smith J.C. Ulwick R.P. Vancour 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(10):77-80
Measurements of the precipitation of electrons and positive ions (in the keV to MeV range) detected aboard eight rockets launched from Northern Scandinavia are reported together with corresponding satellite data. The downgoing integral fluxes indicate the temporal fluctuations during each flight. Height profiles of the energy deposition into the atmosphere at different levels of geomagnetic disturbance are given. 相似文献
735.
Krishnamoorthy B.M. Krishnamurthy M.R. 《IEEE transactions on aerospace and electronic systems》1982,(1):58-75
The asynchronous performance of a polyphase reluctance machine with rotor provided with axial slits is investigated for the first time on the basis of conductor boundary treated as a flux line. Theoretical and experimental investigations are presented for rotors with 1) many values of pole arc/pole pitch ratio, 2) varying slot depths, 3) slots on either pole faces or slot portions or both of them, and 4) with and without terminating end rings. Their comparison with predictions leads to interesting conclusions. 相似文献
736.
G. Courtès M. Golay M. Viton W. Bentz J.M. Deharveng M. Laget J. Donas J.P. Sivan B. Milliard 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(11):81-88
The use of the 2 000 Å transmission window of the atmosphere permitted to observe for the first time from a balloon gondola the nearest galaxies ; 30 arc/sec. resolution images were obtained for M 31, spiral arms and nucleus, M 33, M 101, with their external spiral structure, M 82 and NGC 3 077. Nearly three hundred more distant galaxies have been detected up to the magnitude V = 13. Several HII regions of the Galaxy have been observed, chiefly NGC 7 000 and the Cyghus Loop. Numerous blue stars of the halo have been identified. 相似文献
737.
We have tested the performance of the VISION System Blood Analyzer, produced by Abbott Laboratories, during parabolic flight on a KC-135 aircraft (NASA 930). This fully automated instrument performed flawlessly in these trials, demonstrating its potential for efficient, reliable use in a microgravity environment. In addition to instrument capability, we demonstrated that investigators could readily fill specially modified test packs with fluid during zero gravity, and that filled test packs could be easily loaded into VISION during an episode of microgravity. 相似文献
738.
D. Hovestadt G. Gloeckler H. H?fner B. Klecker C.Y. Fan L.A. Fisk F.M. Ipavich J.J. OGallagher M. Scholar 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(3):61-64
The ionic charge states of helium, carbon, oxygen, and iron have been determined for three solar particle enhancements by an electrostatic deflection analyzer, which is combined with a thin window proportional counter dE/dX vs. E system. The observations are obtained during the periods September 23 to 29, 1978, June 6 to 8, 1979, and September 15 to 26, 1979, with an instrument onboard the ISEE-3 spacecraft. The mean ionic charge states for He, C, and oxygen exhibit a high degree of ionization with values of Q = 2, 6, and 7.2, respectively. The charge state of iron is near 13 charge units. Variations from flare to flare and within the September 23, 1978 flare are small. The most surprising feature of the charge state measurement is the observation of a small (~10%) but finite contribution of singly ionized helium. 相似文献
739.
A.M. Galper V.G. Kirillov-Ugryumov Yu.D. Kotov L.V. Kurnosova A.V. Kurochkin N.G. Leikov V.I. Logachev L.A. Razorenov Yu.V. Smirnov M.I. Fradkin S.V. Damle P.K. Kunte B.V. Sreekantan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(11):101-106
The report presents some results on the cosmic radiation intensity research carried out with the high-altitude balloons for the period of 1977–1979. The intensity of gamma-radiation with the energy above 40 MeV was measured in two balloon flights at an altitude of 4–7 g/cm2 of residual atmosphere in the vicinity of the geomagnetic equator. A temporal analysis of the intensity to discover fluctuations with periods in the range of 4–60 min was made. Quasi-periodic fluctuations of gamma-radiation intensity with 5 min periods, amplitude ~20% and duration of several hours were discovered. Possible mechanisms of such fluctuation appearance are discussed.The report gives the results of measuring downward, upward and horizontal electron fluxes in the vicinity of the equator. The obtained data and the data provided by satellites are compared. The report discusses the prospects of further joint Soviet-Indian research of cosmic gamma-radiation. 相似文献
740.
F.B. McDonald Z. Fujii P. Ferrando B. Heber A. Raviart H. Kunow N. Lal R. Mller-Mellin G. Wibberenz R. McGuire C. Paizis 《Space Science Reviews》2001,97(1-4):321-325
The combination of Voyager 1 (77.9 AU, 34.4° N) and Voyager 2 (61.2 AU, 24.5° S) at moderate heliolatitudes in the distant heliosphere and Ulysses with its unique latitudinal surveys in the inner heliosphere along with IMP 8 and other satellites at 1 AU constitutes a
network of observatories that are ideally suited to study cosmic rays over the solar minimum of cycle 22 and the onset of
solar activity and the long term cosmic ray modulation of cycle 23. Through 2000.7 there have been three well-defined step
decreases in the cosmic ray intensity at 1 AU with the cumulative effect being in good agreement with the net decrease in
cycle 21 at a comparable time in the solar cycle. Over this period the intensity changes at Ulysses are similar to those at 1 AU. In the distant heliosphere the initial decreases appear to be smaller than those at 1 AU. However
the full effects of the interplanetary disturbances producing the most recent and largest step decrease in the inner heliosphere
have not yet reached V-2.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献