Helioseismology in Space Weather - National Solar Observatory

Helioseismology in Space WeatherIrene González HernándezNational Solar Observatory, Tucson, AZ

Helioseismology of Active RegionsTowards Seismology of Active Regions“The Spatial Distribution of p-Mode Absortion in Active Regions”Braun, D. C., LaBonte B. J. and Duvall, T.L. Jr. 1990, ApJ, 354, 372“Scattering of p-Modes by a Sunspot”Seismic Imaging of Sunspots in theFar Side of the SunLindsey, C. and Braun D., 1990, SolarPhysics, 126, 101Braun, D. C., Duvall, T.L. Jr., LaBonte, B.J., Jefferies, S.M., Harvey, J.W.and Pomerantz, M.A. 1992, ApJ, 391L, 113Time-distance helioseismologyDuvall et al., 1993, Nature, 362,430

Helioseismology of Active RegionTime distance: First seimic image of an active regionusing a local helioseismology technique (time-distance)Ambient Acoustic Imaging: Constructed outgoing intensitymap and phase-shift map at the surface and 10 Mm at 5mHzØ Chang, H.-K.,Chou, D.-Y.;Labonte, B. and the TONTeam, 1997, Nature, 389,825.Ø Chou, D.-Y., 2000, SolarPhysics, 192, 241Helioseismic holography: First seimic image of activeregions in the far side of the SunDuvall, T., D’Silva, S., Jefferies, S.M., Harvey,J.W. and Schou, 1996, Nature, 379, 235Lindsey, C. and Braun, D. C. 2000, Science, 287, 1799

Helioseismology of Active Regions16 oq Hill, F; 1988, ApJ,333,996q Patrón, J.; Hill, F.;Rhodes,E.J.,Jr.;Korzennik,S. G. andCacciani,A., 1995, ApJ, 455,746

Helioseismology of Active RegionsCourtesy of R. Komm

Helioseismic Imaging of the FarsidePhase of theCorrelation∫C( r,z,τ ) dtH ( r,z,t)H ( r,z,t + τ )=+−0 180 360Carrington Longitude (degrees)

Current Far-side MapsMagnetic field strength calibration(González Hernández, I.; Hill, F.;Lindsey, C, 2007, ApJ)Solar cycle variation of the “quiet Sun” inthe far-side maps (González Hernández,Scherrer and Hill 2009 ApJ Letters)Confidence level (González Hernández, Hill,Scherrer, Lindsey, and Braun 2010 SpaceWeather Journal)C. Long. Latitude Phase-shift Prob. Effective-Area Date-of-return Front-sidenumber203.039993 -19.876875 -0.159418 87 84.239998 20100911 NOAA 11100

Solar Spectral Irradiance ForecastingLyman-alpha scattered mapof the farside from SWANFontenla, J. M., et al., 2009, Advances inSpace Research, 44, 457, “Solar IrradianceForecast and Far-Side Imaging”

Input DataSolarMagnetogramDataIncorporating Far-Side Observationsinto ADAPTIntelligent FrontEnd !Import & SelectDataforData AssimilatorADAPTInitial ConditionsData AssimilatorForecast Step:use the WHmodel tocalculateforecastModeling / ForecastingApplicationsImprovedSolar SynopticMapsCoronal &Solar WindModelsWSA+ENLILMagneticFieldVarianceAnalysis Step:combineobservations withforecastFar-side mapPolarity+ErrorEstimationAssimilation ResultsGlobalMagnetic FieldWSA-ENLILSolar WindDiagram of the general data flow and processing of ADAPT: the Intelligent Front End imports and selects the bestavailable magnetogram data, along with estimated uncertainties, to be assimilated by the ensemble least-squares (EnLS)method with the latest WH flux transport map of the global solar magnetic field. These maps are then used as input forcoronal and solar wind models, e.g., WSA-ENLIL (Odstrcil et al. , 2005) .

ADAPT: Photospheric Field(Before & After Far-Side Active Region Insertion)Large, GONGdetected far-sideactive regioninserted into theADAPT map on July1, 2010June 30, 2010Without Active RegionInsertedJuly 1, 2010With Active RegionInsertedArge, N. et al (Solar Wind 13 presentation, June 2012)

• WSA Coronalholes - Whitecontours• STEREO A&BEUVI - GreenareasWSA Model Coronal Holes vs.STEREO EUVI ObservationsJuly 1, 2010June 30, 2010STEREO BWithout Active Region Inserted July 1, 2010Note coronalhole changesSTEREO AWith Active Region InsertedArge, C. N. et al (Solar Wind 13 presentation, June 2012)

WSA Solar Wind Speed vs Observationsat STEREO BWithout Far-Side Active Region Inserted4 Day Advanced Predictions and STEREO B ObservationsWith Far-Side Active Region Inserted4 Day Advanced Predictions and STEREO B ObservationsICMEFar-side Active regionInserted on July 1 at 20 UTArge, C. N. et al (Solar Wind 13 presentation, June 2012)

F 10.7 Forecasting Using ADAPT(with/without Far-side)Far-side data merged withADAPT map on July 1 at 20 UT.Henney, C. et al (26 th NSO Workshop presentation, May 2012)

A Full Sun Magnetic Index from HelioseismologyInferencesComparison of the Near Side SeismicMagnetic Index (NSSMI) with the MountWilson Sunspot Index (MWSI) and the F10.7observations from the beginning of 2002 tothe end of 2005. The simultaneous Far SideSeimic Magnetic Index (FSSMI) and the fullSun Seismic Magnetic Index are presented inthe same figure. The characteristic 27-daymodulation can be seen in both the near-sideand the far-side indices. Two cases have beenhighlighted with lines separated by 14 days. (I.Gonzalez Hernandez, M. Diaz Alfaro, K.Jain, W.K. Tobiska, D.C. Braun, F. Hill, F.Perez Hernandez, 2012, SoPh, submitted)

Validation of far-side seismic mapsSTEREOMay 3 2013HMIGONG

Future (Easy) ImprovementsGONGHMISTEREO

Far-side seismic maps: Next GenerationScientific Products for modelersAR Detection/Localization forSpace Weather forecastersMagnetic FieldStrengthUncertaintiesProbabilityEffective AreaFits Files

Flares and subsurface dynamicsUsing quantities averaged over the disk passage of active regions, we find that, while there is a considerable spread of the flux andvorticity values, they are more or less linearly related. We distinguish the level of flare activity by X-ray flare class and find that largeflux or large vorticity values are sufficient for an active region to produce low-intensity C-class flares. Active regions that producehigh-intensity X-class flares are characterized by large values of both flux and vorticity. Active regions that produce M-class flaresof intermediate intensity are characterized by large vorticity values. The inclusion of solar subsurface vorticity thus helps todistinguish between flaring and nonflaring active regions.Komm, R. and Hill, F. 2009, JGRA, 114

Flares and subsurface dynamicsTotal flareintensity of activeregions duringtheir diskpassage as afunction ofunsignedsubsurfacevorticity at 12Mm.Two-dimensionalhistogram of thenumber of activeregion as afunction ofunsignedmagnetic flux andunsignedsubsurfacevorticity at 12 Mm.Komm, R. and Hill, F. 2009, JGRA, 114

Flares and subsurface dynamicsReinard, A.A. et al., 2010, ApJ, 710, 121

Emerging Active RegionsOriginal Paper: Ilonidis, S.,Zhao, J. and Kosovichev, A. , 2011,Science 333,993,“Detection of Emerging Sunspot Regions in the Solar Interior”-11 hoursIlonidis, S.,Zhao, J. and Kosovichev, A. 2012, Proc.Of the 61 st Fujihara Seminar: Progress in solar/stellar physics with helio-and asteroseismology-3 hoursAnalysis of 9 quiet-Sun regions to estimate noiselevel: quiet Sun showed no significant travel-timeperturbations, standard deviation was 3.3,yielding S/N for AR’s 10488 and 8164 4.9 and4.2 respectivelyThese travel-time anomaliescorrespond to very large speeds !!

Emerging Active RegionsHelioseismic holography is applied tosamples of the two populations (preemergenceand without emergence), eachsample having over 100 members, whichwere selected to minimize systematic bias,as described in Leka et al.Birch, A. et al, 2012, ApJ, 762We find that there are statistically significantsignatures (i.e., difference in the means of morethan a few standard errors) in the averagesubsurface flows and the apparent wave speed thatprecede the formation of an active region. Themeasurements here rule out spatially extendedflows of more than about 15 m/s in the top 20Mm below the photosphere over the course of theday preceding the start of visible emergence.These measurements place strong constraints onmodels of active region formation.

Emerging Active RegionsBirch, A. et al, 2012, ApJ, 762

Emerging Active Regionsq Braun, D. C., Science, 336, 296. “Comment on Detection of Emerging SunspotRegions in Solar Interiorq Ilonidis, S., Zhao J. and Kosovichech, A. “Response to Comment on Detection ofEmerging Sunspot Regions in Solar Interiorü On the origing of the large time difference: “The observed phase-shifts can be causednot only by sound-speed and magnetic-field perturbations or plasma flows, but also by morecomplex effects such as absorption and scattering. There has been also evidence, both fromobservations and simulations, that submerged magnetic regions can modify the acoustic powerabove them”q Braun, D. C., 2012, Solar Physics, tmp 306B “Helioseismic Holography of anArtificial Submerged Sound Speed Perturbation and Implications for the Detection ofPre-emergence Signatures of Active Regions

Emerging Active RegionsDeep focusing travel time maps ofthe Active Region 10488 The focusdepth for these measurements covers40-70 Mm. The color scale in thetravel time maps covers theperturbation range 0 (blue) to -15(red) seconds.The maximum time shiftmagnitude is observed at around1:30 UT, October 26.The magnetic fields before and afterthe emergence time and thecontinuum image for a later time arepresented in the last three panels ofthe bottom row.Courtesy of Shukur Kholikov (Solar Physics accepted)

Ø Far-side seismic mapsSummary• Already used as a space weather tool• Improve stability of signal and detection capability.• Encouraging results when using as input to solar models for spaceweather in case studies.Ø Flare activity and subsurface flows• Statistical analyses show potential• Need to be investigated for individual eventsØ Predicting the emergence of active regions• Encouraging and interesting initial results• Work in progress…..