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31.
Persistent 22-year cycle in sunspot activity: Evidence for a relic solar magnetic field 总被引:1,自引:0,他引:1
We use the recently presented group sunspot number series to show that a persistent 22-year cyclicity exists in sunspot activity throughout the entire period of about 400 years of direct sunspot observations. The amplitude of this cyclicity is about 10% of the present sunspot activity level. A 22-year cyclicity in sunspot activity is naturally produced by the 22-year magnetic polarity cycle in the presence of a relic dipole magnetic field. Accordingly, a persistent 22-year cyclicity in sunspot activity gives an evidence for the existence of such a relic magnetic field in the Sun. The stable phase and the roughly constant amplitude of this cyclicity during times of very different sunspot activity level strongly support this interpretation. 相似文献
32.
A. T. Kalloghlian R. A. Kandalyan H. M. K. Al-Naimiy A. M. Khassawneh 《Astrophysics》2001,44(3):292-304
The near and mid-IR properties of barred and unbarred spiral galaxies are discussed on the basis of complete samples that were compiled earlier. The two types of spirals are shown not to differ from one another in emission power in the near and mid-IR ranges. Multiple regression and principal component analysis have been applied to investigate near and mid-IR properties of SB and SA galaxies, particularly their relation to X-ray and radio continuum emissions. There are definite differences between SB and SA spirals in the near and mid-IR. In the case of SB galaxies, the compactness of 10 m emission is closely related to the J - H color index, and the redder J - H color corresponds to relatively more extended emission at 10 m. It is assumed that these are caused by the bar itself, which stimulates enhanced star formation in a barred galaxy with respect to unbarred spiral. 相似文献
33.
We have identified 20 of the 75 unidentified Equatorial Infrared Catalogue Number-1 sources with stars in the BD Catalogue. Two of these are also found in the HD Catalogue. 相似文献
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35.
N. Brice Orange Hakeem M. Oluseyi David L. Chesny Maulik Patel Katie Hesterly Lauren Preuss Chantale Neira Niescja E. Turner 《Solar physics》2014,289(5):1557-1584
Since their discovery 20 year ago, transition region bright points have never been observed spectroscopically. Bright point properties have not been compared with similar transition region and coronal structures. In this work we have investigated three transient quiet Sun brightenings including a transition region bright point (TR BP), a coronal bright point (CBP) and a blinker. We use time-series observations of the extreme-ultraviolet emission lines of a wide range of temperature T (logT=5.3?–?6.4) from the EUV Imaging Spectrometer (EIS) onboard the Hinode satellite. We present the EIS temperature maps and Doppler maps, which are compared with magnetograms from the Michelson Doppler Imager (MDI) onboard the SOHO satellite. Doppler velocities of the TR BP and blinker are ≤?25 km?s?1, which is typical of transient TR phenomena. The Doppler velocities of the CBP were found to be ≤?20 km?s?1 with exception of those measured at logT=6.2 where a distinct bi-directional jet is observed. From an EM loci analysis we find evidence of single and double isothermal components in the TR BP and CBP, respectively. TR BP and CBP loci curves are characterized by broad distributions suggesting the existence of unresolved structure. By comparing and contrasting the physical characteristics of the events we find that the BP phenomena are an indication of multi-scaled self-similarity, given the similarities in both their underlying magnetic field configuration and evolution in relation to EUV flux changes. In contrast, the blinker phenomena and the TR BP are sufficiently dissimilar in their observed properties as to constitute different event classes. Our work is an indication that the measurement of similar characteristics across multiple event types holds class-predictive power, and is a significant step towards automated solar atmospheric multi-class classification of unresolved transient EUV sources. Finally, the analysis performed here establishes a connection between solar quiet region CBPs and jets. 相似文献
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37.
Journal of Seismology - 相似文献
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39.
Dr. E. K. Walton 《International Journal of Earth Sciences》1960,50(1):63-77
Lower Palaeozoic successions in the Southern Uplands are much thicker than previously supposed and sedimentation may have lasted well into Ludlow times. Volcanic rocks are Arenig and Glenkiln in age and are often interbedded with greywackes and shales. Lapworth's concept of the structure as an anticlinorium and a synclinorium is rejected and it is suggested that the rocks have been folded into a series of compound monoclines which face north-westwards. These are probably cut by strike faults which bring up the older beds to the north.
Zusammenfassung Die altpaläozoischen Schichtfolgen in den Südlichen Hochlanden sind viel mächtiger, als bisher angenommen wurde, und die Ablagerung kann bis ins Ludlow gereicht haben. Vulkanite haben Arenig- und Glenkiln-Alter; sie wechsellagern oft mit Grauwacken und Tonschiefern.Lapworths Vorstellung, der tektonische Bau sei ein Antiklinorium und ein Synklinorium, wird bestritten. Es wird angenommen, daß die Gesteine zu zusammengesetzten Monoklinen gefaltet wurden, deren steile Flügel nordwestwärts weisen. Sie werden wahrscheinlich durch streichende Verwerfungen zerschnitten, die die älteren Schichten im Norden herausheben.相似文献
40.
N. VANDENBERGHE 《Sedimentology》1975,22(4):615-622
Grain-size data of Boom clay (Belgium) are represented on CM, AM, LM diagrams as suggested by Passega. They show a typical ‘uniform suspension’ pattern. It is argued that a ‘uniform suspension’ pattern can be due simply to the clay-rich nature of the sediments. As these sediments are not deposited by a single transport mechanism, the ‘uniform suspension’pattern does not necessarily indicate a specific transport mechanism. 相似文献