Coronal mass ejections (CMEs) largely influence the space weather and cause geomagnetic perturbations. Hence, the statistical studies pertaining to the occurrence of CMEs over the solar cycles and their consequence at the near-Earth region are extremely important. For an in-depth understanding, such studies need to be carried out considering various observational aspects of CMEs. With this motivation, here we present a statistical study of radio-loud (RL) and radio-quiet (RQ) CMEs during solar cycles 23 and 24. We also assess their geo-effectiveness and analyze their influence on cosmic ray intensity (CRI). The RL and RQ CMEs constitute 40% and 60% cases, respectively, of the total population of CMEs that arrive the near-Earth region at 1 AU. The mean speed of RL CMEs (≈1170 km s⁻¹) was found to be significantly higher (almost twice) than the mean speed of RQ CMEs (≈519 km s⁻¹) in the low corona while their speed became comparable (≈536 km s⁻¹ for RL and ≈452 km s⁻¹ for RQ CMEs) at near-Earth region. The yearly-averaged speeds of Earth-reaching CMEs follow solar cycle variations. The CRI and geomagnetic Dst index are found to have good negative correlation with speed of Earth-reaching CMEs. RL CMEs were found to be more effective in producing CRI depressions and geomagnetic storms (GSs) in comparison to RQ CMEs; in about 70% cases RL CMEs produced CRI depression and GSs earlier than the RQ CMEs. Superposed epoch analysis suggests strongest depression in CRI occurs 2-5 days and 4-9 days after the onset of RL and RQ CMEs, respectively. Further, GS events show a time-lag of 1-5 days and 3-8 days, respectively, with respect to RL and RQ CMEs.

日冕物质抛射（CME）在很大程度上影响太空天气并引起地磁扰动。因此，有关太阳周期CMEs发生及其在近地区域后果的统计研究极为重要。为了深入理解，需要考虑CME的各种观测方面进行此类研究。出于这种动机，我们在此介绍了太阳周期23和24中的大声（RL）和无声（RQ）CME的统计研究。我们还评估了它们的地球有效性，并分析了它们对宇宙射线强度（CRI）的影响。 。RL和RQ CME分别占到达近地1AU的CME总数的40％和60％。RL CME的平均速度（≈1170km s ^-1）被认为是显著高（几乎两倍），比RQ日冕物质抛射的平均速度（≈519公里S ^-1）的低日冕，而他们的速度变得相当（≈536公里S ^-1的RL和≈452公里S ^{- 1个}RQ CME）。到达地球的CME的年平均速度随太阳周期的变化而变化。发现CRI和地磁Dst指数与到达地球的CME的速度具有良好的负相关性。与RQ CME相比，RL CME在产生CRI凹陷和地磁风暴（GSs）方面更有效。在大约70％的情况下，RL CME比RQ CME更早产生CRI抑郁症和GS。叠加的时代分析表明，CRI最强烈的抑郁症分别发生在RL和RQ CME发作后的2-5天和4-9天。此外，相对于RL和RQ CME，GS事件分别显示出1-5天和3-8天的时滞。