age dependence of em in ar cores... and... some thoughts on the accuracy of atomic data helen mason,...
TRANSCRIPT
![Page 1: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/1.jpg)
Age dependence of EM in AR Cores... and...Some thoughts on the Accuracy of Atomic Data
Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna
Loops-6, Belgium, June 2013
Photo: Giulio Del Zanna
![Page 2: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/2.jpg)
Characteristic loop structures for solar active regions
• Large 1MK loops (171A) seem to be ‘almost isothermal’ and ‘spatially resolved’ by present day instruments such as TRACE, EIS, SDO/AIA.
• Are they?• Check with HiC at 171A • The hot core loops (3MK?) do
not seem to be so well resolved.• Look same in SDO/AIA and HiC. • We can study their footpoints
regions (moss regions).
Micro-flare activity and Dynamic core loops – mini-post-flare?
• Very large ‘Fan’ loops reach far out into the corona, possibly joining remote active regions.
SDO/AIA Observations
ARE ALL THESE LOOPS HEATED IN THE SAME WAY???
![Page 3: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/3.jpg)
Imaging versus spectroscopic observationsImaging instruments
• TRACE, EIT, Stereo/EUVI, SDO/AIA, HiC• Intensity variations...flows, waves or pulses?• Intensity changes – Ne or Te?• Several spectral lines contributing to some wavelength bands?• High cadence and good spatial coverage• Relatively straightforward to analyse
• SoHO/CDS and SUMER, Hinode/EIS, Coronal visible lines
• High cadence at expense of spatial coverage...one slit position
• Uncertainties – jitter, line blending, absolute wavelengths, other instrumental effects – point spread function?
• A nightmare to analyse, very labour intensive...
• SUMER – absolute wavelengths relative to chromospheric lines
• Very good diagnostics: EM, Ne, flows, abundances
Spectroscopic Instruments
![Page 4: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/4.jpg)
: :
TRACE image – 1” res
SOHO/CDS – Mg IX - 6” res
CDS and TRACE: off limb AR quiescent loops (1MK)
• Background subtraction is crucial
• 1 MK TRACE loops, are isothermal across the
loop, but have 0.7 MK footpoints with Ne of
around 2 x 109 cm-3.
• Imaging at 1” seems to resolve single flux tubes
Del Zanna and Mason (2003), Del Zanna (2003)
![Page 5: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/5.jpg)
Emission measure loci plot using CDS data, showing near isothermal temperature (Del Zanna & Mason, 2003)
CDS: ‘warm’ 1MK Quiescent AR Loop
![Page 6: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/6.jpg)
Hinode/EIS spectrum • Hinode/EIS
spectra are dominated by coronal ions (iron, particularly)
Young, Mason et al. (2007, PASJ)
![Page 7: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/7.jpg)
Active region density mapPeter Young, 2007
The high quality of the
EIS data makes density maps
relatively easy to generate
![Page 8: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/8.jpg)
Hinode EIS - temperature and density map for a limb AR
Average electron density map from FeXIII lines
Temperature map from FeXVI/FeXVRed is Log T = 6.7, yellow is Log T= 6.5
Hot, dense AR cores are clearly seen with EIS. XRT shows ‘dynamic’ activity.
O’Dwyer et al, 2011
![Page 9: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/9.jpg)
Impulsive heating, nanoflare trains Klimchuk, Bradshaw, Cargill, Reep
Fix: • Loop length: 2L = 80 Mm• Power: 4 10-3 ergs cm-3 s-1
• Triangular pulse: width 100 sec.
Vary:• Delay between nanoflares
Diagnostics• Tmax, EM(Tmax)• EM ~ Ta, T < Tmax
• EM ~ Tb, T > Tmax
![Page 10: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/10.jpg)
log E
M (
cm-5)
log T
log T
EM(T) of Inter-moss: Tripathi, Mason and Klimchuk, 2011
![Page 11: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/11.jpg)
HINODE/EIS EM
Data points are the average of the EM of regions A, B, C subtracted by the average of EM for Bkg1 and Bkg2 reduced by a factor 4 (see next slide).
Theory versus observations: hot core loopsTripathi, Klimchuk & Mason, 2011
EBTEL SIMULATIONS
Loop half length = 2.4x109 cmDuration of nanoflare = 500s Amplitude = 0.04 erg cm-3 s-1 Repetition time = every 8000sConstant low level heating = 10-6 erg cm-3 s-1
slope
![Page 12: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/12.jpg)
• Active region 11193• First rotation – April 19th, 2011• Second rotation – May 16th, 2011• SDO available
• Active Region 11057• First rotation – March 28th, 2010• Second rotation – April 27th, 2010• NO SDO available
Very carefully selected Inter-moss
MCMC method was used to derive the slope and Ratio.
Age dependence of EM distribution in AR coresTripathi, D., O’Dwyer, B. and Mason, H.E., 2013
![Page 13: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/13.jpg)
NOAA 11193: AIARotation 1 19-Apr-2011 Rotation 2 16-May-2011
![Page 14: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/14.jpg)
AR 11193high temperature emission and slope decreases with age:high to low frequency nanoflares?
From log T = 6.0 to log T = 6.5
Slope = 2.61 ± 0.32Ratio = 22 ± 12
From log T = 6.0 to log T = 6.5
Slope = 2.14 ± 0.53Ratio = 9 ± 4
Log Ne = 9.7 Log Ne = 9.0
![Page 15: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/15.jpg)
AR 11057high temperature emission and slope decreases with age:high to low frequency nanoflares?
From log T = 6.0 to log T = 6.5
Slope = 3.01 ± 0.12Ratio = 50 ± 11
From log T = 6.0 to log T = 6.5
Slope = 2.81 ± 0.17Ratio = 49 ± 14
![Page 16: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/16.jpg)
Errors in the EM analyses.
Observational errors - EIS (or SDO) calibration- Blends
Errors in the EM/DEM methods-MCMC-Giulio’s method-EM Loci-EM Pottasch-Other methods
Errors in the atomic data-Ionisation balance-Radiative data-electron collision data
Other Uncertainties-elemental abundances-equilibrium?
How to deal with all of these issues?-CHIANTI – v7.1 (soon V8)-Assess errors on individual lines-Look for consistency in results
![Page 17: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/17.jpg)
Comparison between MCMC and Pottasch EM Methods
Tripathi, D. and Ali, S.M., 2013
![Page 18: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/18.jpg)
Comparison between MCMC and Pottasch EM Methods
Tripathi, D. and Ali, S.M., 2013
WARNING: Pottasch EM is only valid if the plasma is multi-thermalMCMC not reliable at low temperatures
![Page 19: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/19.jpg)
Multi-thermal Emission in ARsDel Zanna, 2013
2010 Oct 26 SDO/AIA
171A 193A 335A
![Page 20: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/20.jpg)
Multi-thermal Emission in ARsDel Zanna, 2013
EM for 3MK AR Core loops: Lhs: T_max; rhs: T_eff
----- slope of 3.4
Note consistency of EM for different ion stages of iron
![Page 21: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/21.jpg)
Errors? Gennou et al, 2013: Emission Measure Slope
Probability of the true slope given an observed slope =
3
Uncertainty: ~ 1.1
Guennou et al. (2013)
slope
![Page 22: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/22.jpg)
CHIANTI An atomic database for astrophysics
• UK, USA, Italy• First database to make
atomic data freely available for astrophysics
• First released in 1996• Just released v7.1
Landi et al, 2013, ApJ, 763• Improved coverage in X-ray
range (addressing 94A)• Over 1,000 citation• CHIANTI V8 – 2013?
![Page 23: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/23.jpg)
New Ionisation Balance (Ni ions)
![Page 24: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/24.jpg)
CHIANTI v.7.1: DW data (Landi & Dere 2013) + identifications of Del Zanna (2012). R-matrix data (Del Zanna+2012) provide increased intensities. They will be available in v.8.
CHIANTI V7.1 and CHIANTI V8
![Page 25: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/25.jpg)
G. Del Zanna
Scattering calculation for Fe XII calculations: Fe XII
Serious problems with the Fe XII spectrum.
Many calculations:Flower (1977)
Binello et al (several papers) Storey, Del Zanna, Mason (2005)
Del Zanna (2012)
EUV
4S3/2, 2D3/2, 2D5/2, 2P1/2, 2P3/2
2D3/2
4P1/2
4P3/2
2P1/2
SO
![Page 26: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/26.jpg)
FeXII – Atomic Data re-visited (yet again!!)
Mason & Del Zanna - IRIS meeting 2012
New CC
Old CC
UK APAP Team O’Dwyer, Del Zanna, Badnell, Mason and Storey, 2012, A&A, 537, 22Atomic data for the X-ray lines of Fe VIII and Fe IX (for SDO/AIA, 94A)
Del Zanna, Storey, Badnell and Mason (2012, in press) - new Fe XII atomic dataThe previous R-matrix calculation (Storey et al. 2004) has been extended to include all main n=4 levels (for the soft X-rays)
![Page 27: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/27.jpg)
This plot shows how the density derived from a single, quiet Sun off-limb data-set has changed with time using the Fe XII λ186.88/λ195.12 and Fe XIII λ203.82/λ202.04 density diagnostics. The changes are due to improvements in the atomic data models in CHIANTI.
CHIANTI - Fe XII density diagnostics
![Page 28: Age dependence of EM in AR Cores... and... Some thoughts on the Accuracy of Atomic Data Helen Mason, Durgesh Tripathi, Brendan O’Dwyer and Giulio Del Zanna](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649e365503460f94b259a3/html5/thumbnails/28.jpg)
Summary• More work needs to be done on EM tracking
AR evolution• Errors in the various DEM methods need
checking carefully• New EIS calibration is very important• SDO/AIA responses now much better
understood• Abundances can give problems• Atomic data are much better that they were!• Benchmarking CHIANTI v7.1+ gives good
results• Errors need to be judged for each spectral
line/transition
WE NEED HIGHER SPATIAL RESOLUTION AND HIGHER CADENCE SPECTRAL OBSERVATIONS
IRIS, SOLAR-C and Solar Orbiter