The class variable source GRS 1915+105 exhibits a wide range of time variabilities on timescales of a few seconds to a few days. Depending on the count rates in different energy bands and the nature of the conventional color-color diagram, the variabilities were classified into sixteen classes that were later sequenced in ascending order of Comptonization Efficiency (CE), which is the ratio of power-law and blackbody photons. However, CE estimation is based on an empirical model which does not provide us with a comprehensive picture regarding accretion flow dynamics around the central source. In reality, the accretion flow is comprised of two components: the high angular momentumKeplerian flow in the form of a radiatively efficient disk and a low angular momentumradiatively inefficient sub-Keplerian halo enveloping the disk. These two components contribute differently to the overall flux due to the differences in their radiative efficiencies. Therefore, it is necessary to analyze the spectral behaviors and time variabilities in terms of accretion rates. In χ class, X-ray flux is steady with no significant variation, however various χ subclasses are observed at different X-ray fluxes and variations of count rates across different χ subclasses must be linked to the variation of flow parameters such as the accretion rates, be it the Keplerian disk rate and/or the low angular momentum halo rate. This motivated us to analyze the spectra of the χ class data implementing the physical Two Component Advective Flow (TCAF) solution which directly extracts these two rates from spectral fits. We find that in the χ _2,4 classes, which are reportedly devoid of significant outflows, the spectra could be fitted well applying the TCAF solution alone. In the χ _1,3 classes, which are always linked with outflows, a cutoff power-law model is needed in addition to the TCAF solution. At the same time, the normalization required by this model along with the variation of photon index and exponential roll-off factor provides us with information on the relative dominance of the outflow in the latter two classes. TCAF fit also supplies us with the size and location of the Compton cloud along with its optical depth. Thus by fitting with TCAF, a physical understanding of the flow geometry in different χ classes of GRS 1915+105 has been obtained.

类变量源 GRS 1915+105 在几秒到几天的时间尺度上表现出广泛的时间变异性。根据不同能带的计数率和常规颜色-颜色图的性质，将变量分为 16 类，然后按 Comptonization Efficiency (CE) 的升序排序，CE 是幂律与黑体光子。然而，CE 估计是基于一个经验模型，它不能为我们提供关于中心源周围吸积流动力学的全面图景。实际上，吸积流由两部分组成：以辐射有效圆盘形式出现的高角动量开普勒流和包围圆盘的低角动量辐射效率低的亚开普勒晕。由于它们的辐射效率不同，这两种成分对总通量的贡献也不同。因此，有必要从吸积率的角度分析光谱行为和时间变化。在χ类，X 射线通量是稳定的，没有显着变化，但是在不同的 X 射线通量下观察到各种χ子类，并且不同χ子类的计数率的变化必须与流量参数的变化有关，例如吸积率，无论是开普勒圆盘速率和/或低角动量晕速率。这促使我们分析实施物理双分量对流 (TCAF) 解决方案的χ类数据的光谱，该解决方案直接从光谱拟合中提取这两个速率。我们发现，在据报道没有显着流出的χ _2,4类中，单独应用 TCAF 解决方案可以很好地拟合光谱。在χ _1,3类，总是与流出相关联，除了 TCAF 解决方案之外，还需要一个截止幂律模型。同时，该模型所需的归一化以及光子指数和指数滚降因子的变化为我们提供了后两类中流出的相对优势的信息。TCAF fit 还为我们提供了康普顿云的大小和位置以及它的光学深度。因此，通过与 TCAF 拟合，获得了对 GRS 1915+105 不同χ类中流动几何的物理理解。