Abstract
Helioseismology is the study of the solar interior, through which we extract flow and wave-speed information from Doppler velocity observations at the surface. Local helioseismology involves the study of small regions on the solar disk and is used to create a detailed picture of the interior in that particular region. Perturbations in the flow and wave-speed results indicate, e.g. magnetic-flux or temperature variations. There are multiple methods used in local-helioseismic research, but all current local-helioseismic techniques assume a point-source perturbation. For this study, we develop a new time–distance (TD) helioseismic methodology that can exploit the quasi-linear geometry of an elongated feature, allowing us to i) improve the signal-to-noise ratio of the TD results, and ii) greatly decrease the number of calculations required and therefore the computing time of the TD analysis. Ultimately, the new method will allow us to investigate solar features with magnetic-field configurations previously unexplored. We validate our new technique using a simple \(f\)-mode wave simulation, comparing results of point-source and linear perturbations. Results indicate that local-helioseismic analysis is dependent on the geometry of the system and can be improved by taking the magnetic-field configuration into account.
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Cameron, R., Gizon, L., Duvall, T.L. Jr.: 2008, Helioseismology of sunspots: confronting observations with three-dimensional MHD simulations of wave propagation. Solar Phys.251, 291. DOI . ADS .
Couvidat, S., Zhao, J., Birch, A.C., Kosovichev, A.G., Duvall, T.L. Jr., Parchevsky, K., Scherrer, P.H.: 2012, Implementation and comparison of acoustic travel-time measurement procedures for the Solar Dynamics Observatory/Helioseismic and Magnetic Imager time–distance helioseismology pipeline. Solar Phys.275, 357. DOI . ADS .
Domingo, V., Fleck, B., Poland, A.I.: 1995, The SOHO mission: an overview. Solar Phys.162, 1. DOI . ADS .
Duvall, T.L. Jr., Gizon, L.: 2000, Time–distance helioseismology with \(f\) modes as a method for measurement of near-surface flows. Solar Phys.192, 177. ADS .
Duvall, T.L. Jr., Jefferies, S.M., Harvey, J.W., Pomerantz, M.A.: 1993, Time–distance helioseismology. Nature362, 430. DOI . ADS .
Duvall, T.L. Jr., Kosovichev, A.G., Scherrer, P.H., Milford, P.N.: 1996, Detection of subsurface supergranulation structure and flows from MDI high-resolution data using time–distance techniques. In: American Astronomical Society Meeting Abstracts #188, Bull. Am. Astron. Soc.28, 898. ADS .
Duvall, T.L. Jr., Kosovichev, A.G., Scherrer, P.H., Bogart, R.S., Bush, R.I., De Forest, C., Hoeksema, J.T., Schou, J., Saba, J.L.R., Tarbell, T.D., Title, A.M., Wolfson, C.J., Milford, P.N.: 1997, Time–distance helioseismology with the MDI instrument: initial results. Solar Phys.170, 63.
Giles, P.M.M.: 1999, Time–distance measurements of large scale flows in the solar convection zone. PhD thesis, Stanford University. Chapter 2.
Gizon, L., Birch, A.C.: 2004, Time–distance helioseismology: noise estimation. Astrophys. J.614, 472. DOI .
Gizon, L., Birch, A.C.: 2005, Local helioseismology. Liv. Rev. Solar Phys.2, 6. DOI . ADS .
Gizon, L., Birch, A.C., Spruit, H.C.: 2010, Local helioseismology: three-dimensional imaging of the solar interior. Annu. Rev. Astron. Astrophys.48, 289. DOI . ADS .
Gouédard, P., Stehly, L., Brenguier, F., Campillo, M., Colin de Verdière, Y., Larose, E., Margerin, L., Roux, P., Sánchez-Sesma, F.J., Shapiro, N.M., Weaver, R.L.: 2008, Cross-correlation of random fields: mathematical approach and applications. Geophys. Prospect.56, 375. DOI .
Hess Webber, S.A.: 2016, Coronal holes and solar \(f\)-mode wave scattering off linear boundaries. PhD Thesis, George Mason University. DOI . ADS .
Hill, F.: 1988, Rings and trumpets – three-dimensional power spectra of solar oscillations. Astrophys. J.333, 996. DOI . ADS .
Hindman, B.W., Gizon, L., Duvall, T.L. Jr., Haber, D.A., Toomre, J.: 2004, Comparison of solar subsurface flows assessed by ring and time–distance analyses. Astrophys. J.613, 1253. DOI . ADS .
Howe, R., Haber, D.A., Bogart, R.S., Zharkov, S., Baker, D., Harra, L., van Driel-Gesztelyi, L.: 2013, Can we detect local helioseismic parameter shifts in coronal holes? J. Phys. Conf. Ser.440, 012019.
Ilonidis, S., Zhao, J., Kosovichev, A.: 2011, Detection of emerging sunspot regions in the solar interior. Science333, 993. DOI . ADS .
Lindsey, C., Braun, D.C.: 1997, Helioseismic holography. Astrophys. J.485, 895. DOI . ADS .
Lindsey, C., Braun, D.C., Jefferies, S.M.: 1993, Local helioseismology of subsurface structure. In: Brown, T.M. (ed.) GONG 1992. Seismic Investigation of the Sun and Stars, CS-42, Astron. Soc. Pacific, San Francisco, 81. ADS .
Lobkis, O.I., Weaver, R.L.: 2001, On the emergence of the Green’s function in the correlations of a diffuse field. J. Acoust. Soc. Am.110, 3011. DOI .
Pesnell, W.D., Thompson, B.J., Chamberlin, P.C.: 2012, The Solar Dynamics Observatory (SDO). Solar Phys.275, 3. DOI . ADS .
Scherrer, P.H., Bogart, R.S., Bush, R.I., Hoeksema, J.T., Kosovichev, A.G., Schou, J., Rosenberg, W., Springer, L., Tarbell, T.D., Title, A., Wolfson, C.J., Zayer, I. (MDI Engineering Team): 1995, The solar oscillations investigation – Michelson Doppler Imager. Solar Phys.162, 129. DOI . ADS .
Schou, J.: 2004, Low frequency modes. In: Danesy, D. (ed.) SOHO 14 Helio- and Asteroseismology: Towards a Golden Future, SP-559, ESA, Noordwijk, 134. ADS .
Schou, J., Scherrer, P.H., Bush, R.I., Wachter, R., Couvidat, S., Rabello-Soares, M.C., Bogart, R.S., Hoeksema, J.T., Liu, Y., Duvall, T.L., Akin, D.J., Allard, B.A., Miles, J.W., Rairden, R., Shine, R.A., Tarbell, T.D., Title, A.M., Wolfson, C.J., Elmore, D.F., Norton, A.A., Tomczyk, S.: 2012, Design and ground calibration of the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO). Solar Phys.275, 229. DOI . ADS .
Tsai, V.C.: 2010, The relationship between noise correlation and the Green’s function in the presence of degeneracy and the absence of equipartition. Geophys. J. Int.182, 1509. DOI . ADS .
Acknowledgments
This research was conducted mainly at George Mason University and NASA’s Goddard Space Flight Center with the support of NASA’s SDO mission, with collaborations at Stanford University and Max Planck Institute for Solar System Research. The project is now being continued through NASA contract NAS5-02139 (HMI) at Stanford University. All SDO/AIA and HMI data are archived and made available by the Joint Science Operations Center (JSOC: jsoc.stanford.edu/). The authors would like to thank T. Duvall, R. Cameron, and A. Birch for their theoretical guidance and implementation help on this project. The authors would also like to thank B. Hindman and L. Gizon for permitting the use of their figures in this article (Figures 1 and 6).
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Hess Webber, S.A., Pesnell, W.D. A Time–Distance Helioseismology Method for Quasi-Linear Geometries. Sol Phys 294, 151 (2019). https://doi.org/10.1007/s11207-019-1547-y
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DOI: https://doi.org/10.1007/s11207-019-1547-y