DEM Temperature Analysis of Post-Flare Loops Using Hinode's X-Ray - PowerPoint PPT Presentation

DEM Temperature Analysis of Post-Flare Loops Using Hinode's X-Ray Telescope Kathy Reeves and Mark Weber Harvard-Smithsonian Center for Astrophysics

DEM Method • SSW routine xrt_dem_iterative • Forward fitting routine - a solution is guessed and iterated upon until the χ 2 between the actual and model observations is minimized. • Monte Carlo runs on the data using values varied normally by the sigma error gives an estimate of the error in the DEM.

DEM Method 22 DEM from obs Log DEM (cm ! 5 K ! 1) 20 18 16 14 12 10 6.0 6.5 7.0 7.5 8.0 Log T (K)

DEM Method 22 22 DEM from obs Log DEM (cm ! 5 K ! 1) '() 234 (56 ! 5 - ! 1) 20 20 MC simulations 18 18 16 16 14 14 12 12 10 10 6.0 6.0 6.5 6.5 7.0 7.0 7.5 7.5 8.0 8.0 '() + (-) Log T (K)

DEM Method 22 22 22 DEM from obs Log DEM (cm ! 5 K ! 1) '() 234 (56 ! 5 - ! 1) Log DEM (cm ! 5 K ! 1) 20 20 20 MC simulations Median in each bin 18 18 18 16 16 16 14 14 14 12 12 12 10 10 10 6.0 6.0 6.0 6.5 6.5 6.5 7.0 7.0 7.0 7.5 7.5 7.5 8.0 8.0 8.0 Log T (K) '() + (-) Log T (K)

DEM Method 22 22 22 22 DEM from obs Log DEM (cm ! 5 K ! 1) '()*234*,56 ! 5*- ! 1. Log DEM (cm ! 5 K ! 1) '() 234 (56 ! 5 - ! 1) 20 20 20 20 MC simulations Median in each bin 18 18 18 18 DEM closest to median 16 16 16 16 14 14 14 14 12 12 12 12 10 10 10 10 6.0 6.0 6.0 6.0 6.5 6.5 6.5 6.5 7.0 7.0 7.0 %.0 7.5 7.5 %.5 7.5 8.0 8.0 8.0 8.0 '()*T*,-. Log T (K) Log T (K) '() + (-)

July 10, 2007 C8.2 Flare • Flare peak at 12:40 UT. • A total of 7 filter combinations were observed by XRT starting at 13:10 and 13:20 UT: • Al-poly • Al-poly/Ti-poly • Ti-poly • thick-Al • thin-Be • C-poly/thick-Al • med-Be

July 10, 2007 C8.2 Flare 13:10 A total of 7 filter combinations were observed by XRT: • Al-poly • Al-poly/Ti-poly Al/Poly Be-thin Thick Al • Ti-poly • thick-Al • thin-Be 13:20 • C-poly/thick-Al • med-Be Al/Poly Be-thin Thick Al

Emission Measure Maps 13:10 2-3 MK 3-5 MK 5-8 MK 8-13 MK 13:20 2-3 MK 3-5 MK 5-8 MK 8-13 MK

Some Example DEMs

Some Example DEMs 24 1 1310 23 Log DEM 1320 22 21 20 6.0 6.5 7.0 7.5 8.0 1 Log T (K)

Some Example DEMs 24 1 1310 23 Log DEM 1320 22 21 20 6.0 6.5 7.0 7.5 8.0 1 Log T (K) 24 2 1310 23 Log DEM 1320 22 21 2 20 6.0 6.5 7.0 7.5 8.0 Log T (K)

Some Example DEMs 24 1 1310 23 Log DEM 1320 22 21 20 6.0 6.5 7.0 7.5 8.0 1 Log T (K) 24 2 1310 23 Log DEM 1320 22 3 21 2 20 6.0 6.5 7.0 7.5 8.0 Log T (K) 24 3 1310 23 Log DEM 1320 22 21 20 6.0 6.5 7.0 7.5 8.0 Log T (K)

DEM errors 24 24 13:10 13:20 23 23 Log DEM Log DEM 22 22 21 21 20 20 6.0 6.5 7.0 7.5 8.0 6.0 6.5 7.0 7.5 8.0 0 Log T (K) Log T (K) 24 24 13:10 13:20 23 23 Log DEM Log DEM 22 22 21 21 20 20 6.0 6.5 7.0 7.5 8.0 6.0 6.5 7.0 7.5 8.0 Log T (K) Log T (K) 24 24 13:20 13:10 23 23 Log DEM Log DEM 22 22 21 21 20 20 6.0 6.5 7.0 7.5 8.0 6.0 6.5 7.0 7.5 8.0 Log T (K) Log T (K)

DEM errors 24 24 13:10 13:20 23 23 Log DEM Log DEM 22 22 21 21 20 20 6.0 6.5 7.0 7.5 8.0 6.0 6.5 7.0 7.5 8.0 0 Log T (K) Log T (K) 24 24 13:10 13:20 23 23 Log DEM Log DEM 22 22 21 21 20 20 6.0 6.5 7.0 7.5 8.0 6.0 6.5 7.0 7.5 8.0 Log T (K) Log T (K) 24 24 13:20 13:10 23 23 Log DEM Log DEM 22 22 21 21 20 20 6.0 6.5 7.0 7.5 8.0 6.0 6.5 7.0 7.5 8.0 Log T (K) Log T (K)

Emission measure: 2-13 MK • Loop characterized by emission measure loss • Decrease in intensity in XRT images due to decreasing emission measure, not decreasing temperature Red = EM gain Blue = EM loss

Dec 13, 2007 B8 Flare • Flare peak at approximately 4:04 UT. • A total of 8 filter combinations were observed by XRT starting at 4:15 and 4:30 UT: • C-poly • Al-poly • Al-poly/Ti-poly • Ti-poly • thick-Al • thin-Be • thick-Be • med-Be Al/Poly Al/Poly

Dec 13, 2007 B8 Flare 4:15 Al/Poly Be-thin Thick Al 4:30 Al/Poly Be-thin Thick Al Al/Poly Al/Poly

Emission Measure Maps 4:15 2-3 MK 3-5 MK 5-8 MK 8-13 MK 4:30 2-3 MK 3-5 MK 5-8 MK 8-13 MK

Some example DEMs

Some example DEMs 24 1 0415 23 Log DEM 0430 22 21 20 6.0 6.5 7.0 7.5 8.0 Log T (K) 1

Some example DEMs 24 1 0415 23 Log DEM 0430 22 21 20 6.0 6.5 7.0 7.5 8.0 Log T (K) 24 2 0415 23 Log DEM 0430 22 21 1 20 6.0 6.5 7.0 7.5 8.0 2 Log T (K)

Some example DEMs 24 1 0415 23 Log DEM 0430 22 21 20 6.0 6.5 7.0 7.5 8.0 Log T (K) 3 24 2 0415 23 Log DEM 0430 22 21 1 20 6.0 6.5 7.0 7.5 8.0 2 Log T (K) 24 3 0415 23 Log DEM 0430 22 21 20 6.0 6.5 7.0 7.5 8.0 Log T (K)

Emission measure: 2-13 MK • Some emission measure loss near the footpoints, some emission measure gain in the loop • Signature of chromospheric evaporation? • Cooling causes intensity decrease in Red = EM gain XRT images Blue = EM loss

Conclusions • The July 10, 2007 flare decreases in XRT intensity due to decreasing emission measure in the loop • The December 13, 2007 flare decreases in XRT intensity due to cooling of the flare plasma • The DEM method is a useful tool for deconvolving temperature and density effects on intensity

Future and related work • Better data sets: many-filter sets with a higher cadence, non-saturated data closer to peak of flare • Incorporate data from other Hinode instruments: EIS for temperature and emission measure comparisons, SOT for underlying magnetic field structure • See posters by DeLuca, Weber, Schmelz & Hannah.