Download presentation
Presentation is loading. Please wait.
1
Flare Flux vs. Magnetic Flux …extending previous studies to new regimes
2
Fisher et al. (1998) found that active region (AR) non-flare soft X-ray luminosity is L SXR 1.19. is total unsigned magnetic flux r s is the Spearman rank-order coefficient They did a principle components analysis, including L SXR vs. properties of B, J, and other aspects of photospheric fields; the correlation with was the most significant.
3
Building upon this work, Pevtsov et al. (2003) looked at non-flare L SXR vs. beyond AR fields. Our group has taken to referring to this relationship as “Pevtsov’s Law”. L SXR 1.15
4
Building upon this work, Pevtsov et al. (2003) looked at non-flare L SXR vs. beyond AR fields. Our group has taken to referring to this relationship as “Pevtsov’s Law”. G,K,M dwarfs T-Tauri stars whole Sun ARs X-ray bright points quiet sun L SXR 1.15
5
Pevtsov et al. (2003) correlated non-flare soft X- ray luminosity L SXR vs. magnetic flux over 12 dex. Our group has taken to referring to this relationship as “Pevtsov’s Law”. G,K,M dwarfs T-Tauri stars whole Sun ARs X-ray bright points quiet sun L SXR 1.15
6
Q: How does GOES flare flux vary with ? Slope differs! (but N is low) AR GOES flux is averaged over disk-passage time (see below) = whole-AR
7
RHESSI can do MUCH BETTER than my sophomoric approach! One could spatially bin RHESSI flare emission, and correlate that emission with MDI’s from the same bins. There might be considerable scatter in RHESSI emission vs. MDI’s , since flares have a power- law distribution. But perhaps less “participates” in smaller flares.
8
We’ve got the entire MDI full-disk magnetogram archive, through fall 2007, on local machines. We can easily copy the RHESSI-era data from the archive to a machine that’s cross-mounted with RHESSI data.
9
A Couple of Slides on Flare Statistics Follow…
10
ASIDE: It’s been known since the dark ages that flares obey a power-law distribution. From Hudson (1991), this plot shows results from several studies. Power laws (a.k.a., polynomials) are scale invariant – i.e., there is no characteristic or average flare energy.
11
Schrijver (2007) found a rough maximum GOES flare flux vs. magnetic flux near polarity inversion lines (PILs). R is the summed near PILs As expected, there are more weak flares than strong flares.
12
It might be that the spectral index in the flare power-law N(E) ~ E varies with . Here, I’ve added a 3 rd dimension to a Schrijver-like plot.
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.