Time series of high resolution photospheric spectra in a quiet region of the sun I. Analysis of global and spatial variations of line parameters
Time series of high resolution photospheric spectra in a quiet region of the sun I. Analysis of global and spatial variations of line parameters
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太阳安静区高分辨率光球光谱时间序列Ⅰ.线参数全局和空间变化分析
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
A. Hanslmeier
中科院分区：
文献类型：
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作者：
K. Puschmann;M. Vázquez;J. Bonet;B. R. Cobo;A. Hanslmeier
德国真空塔望远镜（Observatorio del Teide）在圆盘中心安静的太阳下拍摄了50分钟的一维狭缝光谱图时间序列，用于研究不同线参数的全球和空间变化。为了确定光球层的垂直结构，我们考虑了两条高度分离的谱线。数据已被过滤的p-模式，以隔离纯对流现象。从我们的研究的整体相关系数和相干性和相移之间的几个线参数的分析，可以报告以下结果。对流速度模式保留大于1的结构。�� 0到最高层的照片-球（10435公里）。然而，在这些层处，在强度图案中仅结构大于2。�� 0仍然与那些在连续水平，虽然显示反转的亮度对比。这证实了我们在140公里高空发现的逆温现象。从相移分析中得出了重力波叠加到对流运动的可能证据。我们将半峰全宽和等效宽度作为到颗粒边界的距离的函数，作为增强的湍流和/或强速度梯度的结果，在颗粒间通道的行为。
A 50 min time series of one-dimensional slit-spectrograms, taken in quiet sun at disk centre, observed at the German Vacuum Tower Telescope (Observatorio del Teide), was used to study the global and spatial variations of different line pa- rameters. In order to determine the vertical structure of the photosphere two lines with well separated formation heights have been considered. The data have been filtered of p-modes to isolate the pure convective phenomenon. From our studies of global correlation coefficients and coherence and phase shift analyses between the several line parameters, the following results can be reported. The convective velocity pattern preserves structures larger than 1 . �� 0 up to the highest layers of the photo- sphere (∼435 km). However, at these layers, in the intensity pattern only structures larger than 2 . �� 0 are still connected with those at the continuum level although showing inverted brightness contrast. This confirms an inversion of temperature that we have found at a height of ∼140 km. A possible evidence of gravity waves superimposed to the convective motions is derived from the phase shift analysis. We interprete the behaviour of the full width at half maximum and the equivalent width as a function of the distance to the granular borders, as a consequence of enhanced turbulence and/or strong velocity gradients in the intergranular lanes.