HELIOSEISMOLOGY Maria Pia Di Mauro INAF Istituto di

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HELIOSEISMOLOGY Maria Pia Di Mauro INAF- Istituto di Astrofisica Spaziale e Fisica Cosmica Rome

HELIOSEISMOLOGY Maria Pia Di Mauro INAF- Istituto di Astrofisica Spaziale e Fisica Cosmica Rome (Italy) IHY Conference “The Sun, the Heliosphere, and the Earth” Bad Honnef, May 14 -18 2007

The story. . . Periodic Motions P 5 min of the absorption lines of

The story. . . Periodic Motions P 5 min of the absorption lines of the photospheric spectrum (Leighton et al. 1962) PULSATIONS OF THE PHOTOSPHERE!!! Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Normal Modes Acoustic waves trapped in resonant cavities p modes (Ulrich 1971, Leibacher &

Normal Modes Acoustic waves trapped in resonant cavities p modes (Ulrich 1971, Leibacher & Stein 1972) Normal modes n radial order l harmonic degree m azimuthal order Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

The proof Deubner 1975 Maria Pia Di Mauro - IHY Conference Bad Honnef, May

The proof Deubner 1975 Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Patches of the solar surface oscillate up and down These data from the SOI/MDI

Patches of the solar surface oscillate up and down These data from the SOI/MDI instrument on board the SOHO satellite 1024 x 1024 points over visible disk 1 -minute cadence or better One Million of indipendent modes excited. Each mode with a different tone!! Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Mode trapping Eigenfunction oscillates as function of r when Maria Pia Di Mauro -

Mode trapping Eigenfunction oscillates as function of r when Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Helioseismology Study of the solar oscillations observed at the surface to probe the structure

Helioseismology Study of the solar oscillations observed at the surface to probe the structure and the dynamics of the Sun Study of oscillations in the Sun in a similar way as geoseismology is the study of earthquakes The technique is very similar to trying to determine the shape of musical instruments from the sound they make. Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Why helioseismology? ìFrequencies depend on the structure of the star r(r) , p(r) ,

Why helioseismology? ìFrequencies depend on the structure of the star r(r) , p(r) , G 1(r) , c(r) but only 2 independent functions: e. g. r(r) and c(r) ìFrequencies can be measured with accuracy (10 -5) ìBasic physics addressed -Equation of state, opacities, neutrinos, general relativity, fluid dynamics ìStellar physics addressed -Stellar evolution, differential rotation, origin of solar magnetism, nature of spatial and temporal inhomogeneitities ìSolar-terrestrial physics addressed -Origin of magnetic storms Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Helioseismic Methods Global Helioseismology Local Helioseismology • Structure and dynamics of pieces • Structure

Helioseismic Methods Global Helioseismology Local Helioseismology • Structure and dynamics of pieces • Structure & dynamics of the solar interior & changes with longitudinally averaged solar time interior & changes with time • Travel time of running sound waves • Frequencies of p modes Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Notable Successes of Helioseismology ØDepth of the solar convection zone (Christensen-Dalsgaard 1985) ØOpacity ØNeutrino

Notable Successes of Helioseismology ØDepth of the solar convection zone (Christensen-Dalsgaard 1985) ØOpacity ØNeutrino Problem ØDiffusion of helium and heavy elements (Basu et al. 1996) ØHelium abundance ØRelativistic effect in the core (Elliot & Kosovichev 1998) ØInternal Dynamics Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

HELIOSEISMIC APPROACHES Forward approach Model Observables Inverse approach Aim of inversion: to make inferences

HELIOSEISMIC APPROACHES Forward approach Model Observables Inverse approach Aim of inversion: to make inferences about localized properties of the solar interior Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

ACTUAL SOUND-SPEED DIFFERENCE SUN-MODEL S Maria Pia Di Mauro - IHY Conference Bad Honnef,

ACTUAL SOUND-SPEED DIFFERENCE SUN-MODEL S Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Turbulent diffusion Christensen-Dalsgaard & Di Mauro 2007 in press Maria Pia Di Mauro -

Turbulent diffusion Christensen-Dalsgaard & Di Mauro 2007 in press Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

New solar surface abundances Asplund et al. (2004 A&A 417, 751) Grevesse & Noels

New solar surface abundances Asplund et al. (2004 A&A 417, 751) Grevesse & Noels 1993 Improvements: §Non-LTE analysis § 3 D atmosphere models Unfortunately this model has a too small CZ and lower He abundance than inferred one!! Montalban et al. 2004 Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

RELATIVE DENSITY DIFFERENCES SUN-MODEL S Maria Pia Di Mauro - IHY Conference Bad Honnef,

RELATIVE DENSITY DIFFERENCES SUN-MODEL S Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

EQUATION OF STATE First adiabatic exponent 1 5/3 in the interior except in the

EQUATION OF STATE First adiabatic exponent 1 5/3 in the interior except in the H and He ionization zones q MHD (Mihalas, Däppen & Hummer 1990)- chemical picture • Pressure ionization (Partition equation) • Non. Relativistic Electron degeneracy • Excited states • Coulomb correction in the Debye-Hückel approximation q. OPAL (Rogers, Swenson & Iglesias 1996) - physical picture • Pressure ionization • Relativistic Electron degeneracy(OPAL 2001) • Excited states Partition equation and degree of ionization • Coulomb correction (many-body quantum physics) • Electron exchange • Quantum diffraction Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

EOS in the surface Difference between SUN and Model S MDI data l<1000 Maria

EOS in the surface Difference between SUN and Model S MDI data l<1000 Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

HELIUM ABUNDANCE IN CZ GY cannot be directly obtained by spectroscopy GY by solar

HELIUM ABUNDANCE IN CZ GY cannot be directly obtained by spectroscopy GY by solar Models matching L Y 0. 27 -0. 28 Now: Helioseismic inversions REFERENCE DATA Y MHD Y OPAL HLH 100 l 1200 0. 2456 0. 007 0. 2489 0. 0028 BBSO 4 l 140 0. 232 0. 006 0. 248 0. 006 Richard et al. (1998) MDI 0 l 140 0. 242 0. 002 0. 248 0. 002 Basu (1998) MDI l 194 Basu & Antia (1995) Kosovichev (1996) Di Mauro et al. (2002) MDI l 1000 0. 2524 0. 0001 0. 2488 0. 0001 0. 2457 0. 0005 0. 2539 0. 0005 Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Internal Rotation simmetry of the Di Mauro et. Rotation al. 1998 breaks spherical. Howe

Internal Rotation simmetry of the Di Mauro et. Rotation al. 1998 breaks spherical. Howe et al. 2000 Sun and splits the frequency of oscillations tachocline rc/R = 0. 67 +/- 0. 05 (Di Mauro et al 1997) Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

The Solar Cycle ® Activity grows and decays over 11 years ® Zones of

The Solar Cycle ® Activity grows and decays over 11 years ® Zones of magnetic activity move towards the equator ® Bands of slower and faster rotation also migrate, ahead of the magnetic bands Deviations from the mean rotation profile as a function of latitude and time Howe et al. 2000 Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

TORSIONAL OSCILLATIONS 0. 99 R 0. 95 R MDI OLA 0. 90 R 0.

TORSIONAL OSCILLATIONS 0. 99 R 0. 95 R MDI OLA 0. 90 R 0. 84 R Differences between inversions of data taken at successive times reveal the “torsional oscillation” Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Torsional oscillations of whole CZ Differencing rotation inversions at successive 72 -day epochs relative

Torsional oscillations of whole CZ Differencing rotation inversions at successive 72 -day epochs relative to solar minimum (1996) shows equatorward and poleward migration of torsional oscillations Vorontsov et al. 2002 Science Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Tachocline Oscillations Howe 2006 The rotation rate appears to show quasi-periodic oscillations of 1.

Tachocline Oscillations Howe 2006 The rotation rate appears to show quasi-periodic oscillations of 1. 3 year period near the base of the convection zone at mid-latitudes Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

ROTATION IN THE CORE MDI l < 100 (Schou et al. 1998)+ ®IRIS l=1

ROTATION IN THE CORE MDI l < 100 (Schou et al. 1998)+ ®IRIS l=1 -3 (Lazreck et al. 1996; Gizon et al 1997, Fossat 1998) ®GONG l=1 -3 (Gavryuseva & Gavryuseva 1998) Di Mauro et al. 1998 ®BISON +LOWL l=1 -4 (Chaplin et al. 1999) ®GOLF l=1 -2 (Corbard et al. 1998) Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

News!!! Solar Gravity Modes detected with GOLF!!! Garcia et al. 2007 on Science last

News!!! Solar Gravity Modes detected with GOLF!!! Garcia et al. 2007 on Science last week 10 years of observations from GOLF Observed g mode is consistent with a model with a rotation rate 3 or 5 times higher than radiative interior Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

Conclusion Improve model tions Observa • Diffusion • Non adiabatic effects • Convection •

Conclusion Improve model tions Observa • Diffusion • Non adiabatic effects • Convection • Rotation • Magnetic fields • EOS • 2 D model • • Longer series of oscillations data g modes Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

The future… SDO Solar Dynamics Observatory, HMI (local helioseismology) NASA launch: 2008 to understand

The future… SDO Solar Dynamics Observatory, HMI (local helioseismology) NASA launch: 2008 to understand variation of magnetic fields dynamical processes and solar structure and its impact on Earth PICARD CNES Launch: 2009 PREMOS (low l and g modes) to study of the Earth climate and Sun variability relationship SO Solar Orbiter ESA Launch: 2013 VIM (local helioseismology at high latitude) to study, by approaching as close as 45 solar radii, the polar regions and the side of the Sun not visible from Earth DYNAMICS Dynamics and Magnetism from the Internal core to the Chromosphere of the Sun, Turck-Chieze et al. Saclay, (France) Launch: ? ? ? Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007

European Helio and Asteroseismology Network Co-ordinated Action funded by FP 6 the 6 th

European Helio and Asteroseismology Network Co-ordinated Action funded by FP 6 the 6 th Framework Programme of the European Union Objective: Bringing together the European research groups active in helio- & asteroseismology. Start date: April 1, 2006 Duration: 48 months Coordinator: Oskar von der Lühe, Kiepenheuer-Institut für Sonnenphysik, Freiburg More information http: //www. helas-eu. org Maria Pia Di Mauro - IHY Conference Bad Honnef, May 14 -18 2007