Hi. Solar activities study needs multiwavelength analysis for space weather studies. You know that Earth atmosphere permits only Optical and Radio wavelength signals from the Sun. One can view a Sunspot orgin in all electromagnetic wavelengths and in magnetogram images given in SDO images.

Solar flare X-ray radiation are filtered by Earth atmosphere. So we use GOES X-ray sensor to know peak flux. Coronal Mass Ejection is a huge plasma magnetic movement can be seen in Coronagraphs (Space like SOHO/LASCO, STEREO COR -2, HI-1 etc.) and ground coronagraphs (like MK4). Solar radio emission (Type II radio burst) is associated with a fast CME(>400 km/s). Dst is an Solar wind disturbed activity index at ground based observation. It is primarily depend on the southward magnetic field component of Interplanetary shock and Interplanetary CME. Some times Dst occurs due to coronal holes. The 1989 Geomagnetic storm is primarily due to a fast and wide CME interaction on Earth magnetosphere. The storm index like Dst, KP, SYM/H index are primarily used to know the magnitude of the storm. Since Earth polar region affects more due to passage of storm. Aurora effect and Dst are related with each other. Only few countries monitoring above indices . But the cosmic ray depletion activity due to ICME can be detected by Neutron monitors. That activity is known as Forbush Decrease activity. The latitude and longitude activity can be studied by combining Neutron monitor data (available worldwide Ex. Izmiran, Oulu etc.).

There is no direct connection between solar flare and magnetic storm.

Article The Solar Flare Myth

I agree Prof. Yuri's statement.