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101.
On 16 June 1972, the Naval Research Laboratory's coronagraph aboard OSO-7 tracked a huge coronal cloud moving outward from the Sun. Concurrent observations of the inner corona made by the High Altitude Observatory at Mauna Loa showed bifurcation of the underlying coronal structure. Together, these observations can be interpreted as evidence for the stretching of the closed fields into a magnetic bottle, extending to at least eight radii from the center of the Sun. 相似文献
102.
Philip H. Scherrer John M. Wilcox Valeri Kotov A. B. Severny Robert Howard 《Solar physics》1977,52(1):vi-12
The mean solar magnetic field as measured in integrated light has been observed since 1968. Since 1970 it has been observed both at Hale Observatories and at the Crimean Astrophysical Observatory. The observing procedures at both observatories and their implications for mean field measurements are discussed. A comparison of the two sets of daily observations shows that similar results are obtained at both observatories. A comparison of the mean field with the interplanetary magnetic polarity shows that the IMF sector structure has the same pattern as the mean field polarity. 相似文献
103.
The Ca ii K line emission from the quiet Sun network does not vary with the 11-year cycle (White and Livinston, 1981). We confirm this result from direct magnetic measurements. This effect is not simply explained by present empirical models of the evolution of surface magnetic fields.Now at Institute for Astronomy, University of Hawaii, Honolulu, Hawaii 96822, U.S.A. 相似文献
104.
Testing the theoretical notion that differences in entrepreneurial skill can enhance the viability of a poor location or detract from the qualities of a good location, this study reviews the historical experience of a number of retailing establishments operated by different firms at the same sites. The ultimate success of stores that had done poorly under previous management tends to confirm that a location is “good'’only so long as the retailer employs effective merchandising and operating policies. 相似文献
105.
Andrew S. Tanenbaum John M. Wilcox Edward N. Franzier Robert Howard 《Solar physics》1969,9(2):328-342
One dimensional magnetograph scans have been used to study the 5-min photospheric velocity oscillations and the supergranulation.
The oscillations in wing brightness lead the oscillations in velocity by less than 90° in the photosphere, and about 90° in
the chromosphere, suggesting that they are traveling waves at lower levels and standing waves at higher levels. Downward flows
have been observed to be coincident with the chromospheric network confirming the hypothesis that material is flowing downward
at supergranular boundaries. 相似文献
106.
A spectrum scanning Stokes polarimeter 总被引:1,自引:0,他引:1
107.
Robert Howard 《Solar physics》1972,25(1):5-13
Observations of the magnetic fields in the polar regions of the Sun are presented for the period 1960–1971. At the start of this interval the fields at the two poles were consistently of opposite sign and averaged around 1 G. Early in 1961 the field in the south decreased suddenly and the field in the north decreased in strength slowly over the next few years. By the mid-1960's the fields at both poles were quite weak and irregular. Throughout the period of these observations the fields at both poles often showed a remarkable tendency to vary in unison. About the middle of 1971 the north polar field became significantly positive, first at lower latitudes, then above 70 °. An autocorrelation analysis of the polar fields in the north shows a weak rotation peak, indicating significant features in these regions. A comparison of field strengths in the east and west quadrants in the north suggests that even at the extreme polar latitudes the following polarity fields are inclined slightly toward the rotation and the preceding polarity field lines are inclined slightly to trail the rotation. 相似文献
108.
A clearly evident large-scale pattern in the interplanetary magnetic field during 1964 is used to search for a similar large-scale pattern in the solar magnetic field. It is found that such a pattern did exist in the photospheric field observations on both sides of the equator over a range of at least 40°N to 35°S. The pattern is basically similar at all these latitudes, and differs from that to be expected from solar differential rotation in three important respects. It is found that the solar magnetic pattern changed at all latitudes investigated within an interval of a few solar rotations. 相似文献
109.
Spectroscopic determinations of solar rotation 总被引:2,自引:0,他引:2
Spectral line shift data obtained from full-disk magnetograms recorded at Mt. Wilson are analyzed for differential rotation. The method of analysis is discussed and the results from the data for 1966 through 1968 are presented. The average equatorial velocity over this period is found to be 1.93 km/sec or 13.76 deg/day (sidereal). This corresponds to a sidereal period of 26.16 days. The average results are = 2.78 × 10-6 - 3.51 × 10-7 sin2
B - 4.43 × 10-7 sin4
B rad/sec, whereB is the solar latitude. This indicates a smaller decrease of angular velocity with latitude than found by earlier investigators. Variations from day to day are caused by large-scale short-lived velocity fields on the solar surface. There also appear to be secular variations.Currently at the Kitt Peak National Observatory, Tucson, Arizona. 相似文献
110.