Emission Measure and Temperature Analysis of the Upper Coronal Source of a Solar Flare     

Z. Ning  D. Li  Q. M. Zhang 《Solar physics》2016,291(6):1783-1798

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Petrology and geochemistry of feldspathic impact‐melt breccia Abar al' Uj 012, the first lunar meteorite from Saudi Arabia          下载免费PDF全文

Marianna Mészáros  Beda A. Hofmann  Pierre Lanari  Randy L. Korotev  Edwin Gnos  Nicolas D. Greber  Ingo Leya  Richard C. Greenwood  A. J. Timothy Jull  Khalid Al‐Wagdani  Ayman Mahjoub  Abdulaziz A. Al‐Solami  Siddiq N. Habibullah 《Meteoritics & planetary science》2016,51(10):1830-1848

Abar al' Uj (AaU) 012 is a clast‐rich, vesicular impact‐melt (IM) breccia, composed of lithic and mineral clasts set in a very fine‐grained and well‐crystallized matrix. It is a typical feldspathic lunar meteorite, most likely originating from the lunar farside. Bulk composition (31.0 wt% Al₂O₃, 3.85 wt% FeO) is close to the mean of feldspathic lunar meteorites and Apollo FAN‐suite rocks. The low concentration of incompatible trace elements (0.39 ppm Th, 0.13 ppm U) reflects the absence of a significant KREEP component. Plagioclase is highly anorthitic with a mean of An_96.9Ab_3.0Or_0.1. Bulk rock Mg# is 63 and molar FeO/MnO is 76. The terrestrial age of the meteorite is 33.4 ± 5.2 kyr. AaU 012 contains a ~1.4 × 1.5 mm² exotic clast different from the lithic clast population which is dominated by clasts of anorthosite breccias. Bulk composition and presence of relatively large vesicles indicate that the clast was most probably formed by an impact into a precursor having nonmare igneous origin most likely related to the rare alkali‐suite rocks. The IM clast is mainly composed of clinopyroxenes, contains a significant amount of cristobalite (9.0 vol%), and has a microcrystalline mesostasis. Although the clast shows similarities in texture and modal mineral abundances with some Apollo pigeonite basalts, it has lower FeO and higher SiO₂ than any mare basalt. It also has higher FeO and lower Al₂O₃ than rocks from the FAN‐ or Mg‐suite. Its lower Mg# (59) compared to Mg‐suite rocks also excludes a relationship with these types of lunar material.  相似文献   

Diagnosing the Source Region of a Solar Burst on 26 September 2011 by Using Microwave Type-III Pairs     

B. L. Tan  M. Karlický  H. Mészárosová  L. Kashapova  J. Huang  Y. Yan  E. P. Kontar 《Solar physics》2016,291(8):2407-2418

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Turnover Frequency in Solar Microwave Bursts with an Extremely Flat Optically Thin Spectrum     

Q. W. Song  H. Nakajima  G. L. Huang  B. L. Tan  Y. Huang  Z. Wu 《Solar physics》2016,291(12):3619-3635

Four microwave bursts have been selected from the Nobeyama Radio Polarimeter (NoRP) observations with an extremely flat spectrum in the optically thin part and a very hard spectral index between 0 and ?1 in the maximum phase of all bursts. It is found that the time evolution of the turnover frequency is inversely proportional to the time profiles of the radio flux in all bursts. Based on the nonthermal gyrosynchrotron theory of Ramaty (Astrophys. J. 158, 753, 1969), the local magnetic field strength and the electron spectral index are calculated uniquely from the observed radio spectral index and the turnover frequency. We found that the electron energy spectrum is very hard (spectral index 1?–?2), and the time variation of the magnetic field strength is also inversely proportional to the radio flux as a function of time in all bursts. Hence, the time evolution of the turnover frequency can be explained directly by its dependence on the local magnetic field strength. The high turnover frequency (several tens of GHz) is mainly caused by a strong magnetic field of up to several hundred gauss, and probably by the Razin effect under a high plasma density over \(10^{10}~\mbox{cm}^{-3}\) in the maximum phase of these bursts. Therefore, the extremely flat microwave spectrum can be well understood by the observed high turnover frequency and the calculated hard electron spectral index.  相似文献   

Isotropic and anisotropic pointing models     

András Pál  Krisztián Vida  László Mészáros  György Mező 《Experimental Astronomy》2016,41(1-2):1-15

This paper describes an alternative approach for generating pointing models for telescopes equipped with serial kinematics, esp. equatorial or alt-az mounts. Our model construction does not exploit any assumption for the underlying physical constraints of the mount, however, one can assign various effects to the respective components of the equations. In order to recover the pointing model parameters, classical linear least squares fitting procedures can be applied. This parameterization also lacks any kind of parametric singularity. We demonstrate the efficiency of this type of model on real measurements with meter-class telescopes where the results provide a root mean square accuracy of 1.5?2 arcseconds.  相似文献   

A Mechanical Drag Coefficient Formulation and Urban Canopy Parameter Assimilation Technique for Complex Urban Environments     

E. Gutiérrez  A. Martilli  J. L. Santiago  J. E. González 《Boundary-Layer Meteorology》2015,157(2):333-341

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Atmospheric Boundary-Layer Evening Transitions: A Comparison Between Two Different Experimental Sites     

Mariano Sastre  Carlos Yagüe  Carlos Román-Cascón  Gregorio Maqueda 《Boundary-Layer Meteorology》2015,157(3):375-399

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The effects of the NAO on the ice phenology of Spanish alpine lakes     

G. Sánchez-López  A. Hernández  S. Pla-Rabes  M. Toro  I. Granados  J. Sigró  R. M. Trigo  M. J. Rubio-Inglés  L. Camarero  B. Valero-Garcés  S. Giralt 《Climatic change》2015,130(2):101-113

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Erratum to: An estimation of ENSO predictability from its seasonal teleconnections     

M. Tasambay-Salazar  M. J. OrtizBeviá  F. J. Alvarez-García  A. M. RuizdeElvira 《Theoretical and Applied Climatology》2015,122(1-2):401-401

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Spatial variability of maximum and minimum monthly temperature in Spain during 1981–2010 evaluated by correlation decay distance (CDD)     

D. Pena-Angulo  N. Cortesi  M. Brunetti  J. C. González-Hidalgo 《Theoretical and Applied Climatology》2015,122(1-2):35-45

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