Peak Temperatures of Large Solar X-Ray Flares and Associated CME Speeds and Widths

Abstract

We recently repeated an earlier analysis by Garcia showing that large (ā‰„M3.0) solar X-ray flares associated with solar energetic particle (SEP) events have significantly lower peak X-ray flux ratios R = (0.04ā€“0.5 nm)/(0.1ā€“0.8 nm), proxies for flare peak temperatures, than those without SEP events. As we expect SEP events to be produced by shocks ahead of fast coronal mass ejections (CMEs), a smaller R for an X-ray flare of a given peak flux Fp should also be more likely to be accompanied by a fast (Vcme > 1000 km sāˆ’1) CME. We confirm this expectation, examine the role played by the ratios R in correlations between Fp and CME speeds Vcme, and then compare CME widths W, Vcme, and R with each other. We consider an apparent conflict between a global scaling model of eruptive events showing Vcme scaling with higher R and our confirmation that the Garcia analysis implies that faster CMEs are associated with flares of lower R. The R values are examined for 16 large flares of the well-studied AR 12192, for which nearly all flares had no associated CMEs. Those flares share the same high values of R as other active region (AR) flares with no CMEs. We also find that small (R values of larger flares with fast CMEs.

Document Details

Document Type
Pub Defense Publication
Publication Date
Mar 01, 2020
Source ID
10.3847/1538-4357/ab6f6c

Entities

People

  • A. G. Ling
  • S. W. Kahler

Organizations

  • Air Force Office of Scientific Research
  • Air Force Research Laboratory

Tags

Readers

  • Solar Physics