Coronal lines - three decades later! Photo: Giulio Del Zanna Helen E. Mason DAMTP, CMS,University of Cambridge Giulio Del Zanna, Pete Storey, Nigel Badnell, Brendan O’Dwyer, Durgesh Tripathi, Peter Young Spectroscopy of the Dynamic Sun, 18-20th April 2012 In honour of George Doschek and Tetsuya Watanabe Visible coronal lines Total Eclipse of the Sun 25th February 1952 Indentifications B. Edlen New calculations for the coronal iron ions - UCL Mason (1974) Fe X, Fe XI, Fe XIV Flower and Nussbaumer – Fe XII and Fe XIII Rocket Flights – 1970s 1970 Eclipse observations Gabriel et al, 1971 Malinovsky & Heroux (1973) The New Forbidden Lines in the Solar EUV Spectrum (including Fe XII) were identified by Carole Jordan. Early days – the Skylab Era – 1970’s George introduced me to Fe XXI and solar flares. We did not only work on flares, we actually wore flares! SMM/UVSP observations of Fe XXI 1354.1A Mason, Shine, Gurman and Harrison, 1986, ApJ, 309, 435 Fe XXI, 1354.1A line is blended with a very convenient C I, 1354.29 ! Doppler shifts relative to the chromosphere Line profiles (blue asymettries – chromospheric evaproation Is there high temperature (10MK) emission in non-flaring AR’s? Study of microflares and emerging flux . Will be seen by IRIS. Skylab Solar Workshops Dere and Mason Spectroscopic Diagnostics of the Active Region: Transition Zone and Corona Summary of electron density diagnostic ratios and atomic physics Coronal values: Ion Temp (MK) Ne ( 109 cm-3) -------------------------------------------------------- Si X 1.3 0.7-1 Fe XII, FeXIII 1.5-1.6 1-6 Fe XIV 1.8 1-3 Fe XV 2.0 6 UCL - Atomic Astrophysics Group was led by Prof Mike Seaton. There was another very strong atomic physics group at QUB, led by Prof Phil Burke. Atomic physics calculations UK APAP team Alan Burgess (UCL/DAMTP) 1933-2011 Iron Project Mike Seaton Dave Hummer Anand Bhatia GSFC CHIANTI An atomic database for astrophysics • UK, USA, Italy • First database to make atomic data freely available for astrophysics • First released in 1996 • Latest release v7 • Complete coverage in X-ray and EUV wavelength range Tuscany – Arcetri Observatory • Over 1000 citation SoHO/Coronal Diagnostic Spectrometer CHIANTI simulated spectrum compared to SOHO-CDS Mason et al, 1997 The Atomic Data Assessment Meeting Abingdon, 1992 Lang (1994) Hinode/EIS spectrum • Spectrum dominated by coronal ions (iron, particularly) Young, Mason et al. (2007, PASJ) Active region seen in 11 iron ions Young, 2007 Hinode/EIS: Intensity, velocity and line width maps Young, 2007 Active region map in Fe XII 195.12 Å Intensity Hinode/EIS can provide detailed maps of electron density, temperature, flows, non-thermal broadenings, and fill factors. Velocity One of the most striking features of Hinode EIS data for active regions are the blueshifts and redshifts. Width Hinode/EIS - Line Ratio Diagnostics – Electron Density Young, 2007 • Certain ratios of emission lines from the same ion are sensitive to the electron density – density is derived purely from atomic physics parameters – no assumptions for element abundances, plasma morphology, etc. Doschek et al, 2007, PASJ Ne and Te Structure along an isolated loop Average temperature and density maps for the AR Average electron density map from FeXIII lines Temperature map from FeXVI/FeXV Red is Log T = 6.7, yellow is Log T= 6.5 O’Dwyer et al, 2011 Moss studies with Hinode/EIS Tripathi, Mason, Young and Del Zanna (2008/9) Comparison of density map from Hinode/EIS FeXII with magnetic field Note that the high densities are in +ve polarity regions not the sunspot side. The density correlates well with the strength of the +ve magnetic field. Comparison of densities from Fe XII and Fe XIII comparisonYoung (2007) Fe XIII Laboratory work – EBIT&LHD NIFS/Japan and USA Yamamoto et al (2008) Watanabe-san Kato-san 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) 2 D3/2 4 P1/2 4 SO P3/2 2 P1/2 EUV 4 2 2 2 2 S3/2, D3/2, D5/2, P1/2, P3/2 G. Del Zanna FeXII – Atomic Data re-visited (yet again!!) UK APAP Team O’Dwyer, Del Zanna, Badnell, Mason and Storey, 2012, A&A, 537, 22 Atomic 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 data The previous R-matrix calculation (Storey et al. 2004) has been extended to include all main n=4 levels (for the soft X-rays) New CC Old CC Mason & Del Zanna - IRIS meeting 2012 Fe XII – Density Diagnostics The new ion model solves the discrepancies in the high densities from the Fe XII EUV lines. New model Old model Del Zanna et al, 2012, in press The End ‘Were you listening or snoozing?’ test What are these spectral lines (A)? 180.4 186.6 193.51 202.04 270.52 284.16 1242.0 1354.1 2406.4 Congratulations and thanks to both George and Tetsuya for all their hard work over the years. .