Abstract
The cause of enhanced acoustic power surrounding active regions, known as the acoustic halo, is not as yet understood. We explore the properties of the enhanced acoustic power observed near disk center from 21 to 27 January 2002, including AR 9787. We find that i) there exists a strong correlation of the enhanced high-frequency power with magnetic-field inclination, with greater power in more horizontal fields, ii) the frequency of the maximum enhancement increases along with magnetic-field strength, and iii) the oscillations contributing to the halos show modal ridges that are shifted to higher wavenumber at constant frequency in comparison to the ridges of modes in the quiet Sun.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Braun, D.C., Lindsey, C., Fan, Y., Jefferies, S.M.: 1992a, Local acoustic diagnostics of the solar interior. Astrophys. J. 392, 739. doi: 10.1086/171477 .
Braun, D.C., Duvall, T.L. Jr., Labonte, B.J., Jefferies, S.M., Harvey, J.W., Pomerantz, M.A.: 1992b, Scattering of p-modes by a sunspot. Astrophys. J. Lett. 391, L113.
Brown, T.M., Bogdan, T.J., Lites, B.W., Thomas, J.H.: 1992, Localized sources of propagating acoustic waves in the solar photosphere. Astrophys. J. Lett. 394, L65. doi: 10.1086/186473 .
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: 10.1007/s11207-008-9148-1 .
Couvidat, S., Rajaguru, S.P.: 2007, Contamination by surface effects of time – distance helioseismic inversions for sound speed beneath sunspots. Astrophys. J. 661, 558. doi: 10.1086/515436 .
Donea, A.C., Lindsey, C., Braun, D.C.: 2000, Stochastic seismic emission from acoustic glories and the quiet Sun. Solar Phys. 192, 321.
Finsterle, W., Jefferies, S.M., Cacciani, A., Rapex, P., McIntosh, S.W.: 2004, Helioseismic mapping of the magnetic canopy in the solar chromosphere. Astrophys. J. Lett. 613, L185. doi: 10.1086/424996 .
Gizon, L., Schunker, H., Baldner, C.S., Basu, S., Birch, A.C., Bogart, R.S., Braun, D.C., Cameron, R., Duvall, T.L., Hanasoge, S.M., Jackiewicz, J., Roth, M., Stahn, T., Thompson, M.J., Zharkov, S.: 2009, Helioseismology of sunspots: A case study of NOAA region 9787. Space Sci. Rev. 144, 249.
Hanasoge, S.M.: 2008, Seismic halos around active regions: A magnetohydrodynamic theory. Astrophys. J. 680, 1457. doi: 10.1086/587934 .
Hanasoge, S.M.: 2009, A wave scattering theory of solar seismic power haloes. Astron. Astrophys. 503, 595. doi: 10.1051/0004-6361/200912449 .
Hartlep, T., Kosovichev, A.G., Zhao, J., Mansour, N.N.: 2010, Signatures of emerging subsurface structures in the Sun. Solar Phys., accepted. arXiv:0901.4585 .
Hindman, B.W., Brown, T.M.: 1998, Acoustic power maps of solar active regions. Astrophys. J. 504, 1029. doi: 10.1086/306128 .
Jacoutot, L., Kosovichev, A.G., Wray, A., Mansour, N.N.: 2008, Realistic numerical simulations of solar convection and oscillations in magnetic regions. Astrophys. J. Lett. 684, L51. doi: 10.1086/592042 .
Jain, R., Haber, D.: 2002, Solar p-modes and surface magnetic fields: Is there an acoustic emission? MDI/SOHO observations. Astron. Astrophys. 387, 1092.
Khomenko, E., Collados, M.: 2006, Numerical modeling of magnetohydrodynamic wave propagation and refraction in sunspots. Astrophys. J. 653, 739. doi: 10.1086/507760 .
Khomenko, E., Collados, M.: 2009, Sunspot seismic halos generated by fast MHD wave refraction. Astron. Astrophys. 506, L5. doi: 10.1051/0004-6361/200913030 .
Kuridze, D., Zaqarashvili, T.V., Shergelashvili, B.M., Poedts, S.: 2008, Acoustic oscillations in a field-free cavity under solar small-scale bipolar magnetic canopy. Ann. Geophys. 26, 2983.
Ladenkov, O.V., Hill, F., Egamberdiev, S.A., Chou, D.Y.: 2002, Acoustic power mapping for active regions from MDI, HLH, and TON data. Astron. Lett. 28, 411. doi: 10.1134/1.1484142 .
Lindsey, C., Braun, D.C.: 2005, The acoustic showerglass. I. Seismic diagnostics of photospheric magnetic fields. Astrophys. J. 620, 1107. doi: 10.1086/426065 .
Muglach, K.: 2003, Dynamics of solar active regions. I. Photospheric and chromospheric oscillations observed with TRACE. Astron. Astrophys. 401, 685. doi: 10.1051/0004-6361:20021901 .
Muglach, K., Hofmann, A., Staude, J.: 2005, Dynamics of solar active regions. II. Oscillations observed with MDI and their relation to the magnetic field topology. Astron. Astrophys. 437, 1055. doi: 10.1051/0004-6361:20041164 .
Parchevsky, K.V., Kosovichev, A.G.: 2007, Three-dimensional numerical simulations of the acoustic wave field in the upper convection zone of the Sun. Astrophys. J. 666, 547. doi: 10.1086/520108 .
Rempel, M., Schüssler, M., Knölker, M.: 2009, Radiative magnetohydrodynamic simulation of sunspot structure. Astrophys. J. 691, 640. doi: 10.1088/0004-637X/691/1/640 .
Sakurai, T.: 1982, Green’s function methods for potential magnetic fields. Solar Phys. 76, 301. doi: 10.1007/BF00170988 .
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.
Shelyag, S., Erdélyi, R., Thompson, M.J.: 2006, Forward modeling of acoustic wave propagation in the quiet solar subphotosphere. Astrophys. J. 651, 576. doi: 10.1086/507463 .
Simoniello, R., Finsterle, W., García, R.A., Salabert, D., Jiménez, A.: 2009, Evidence of increasing acoustic emissivity at high frequency with solar cycle 23 in Sun-as-a-star observations. In: Guzik, J.A., Bradley, P.A. (eds.) Am. Inst. Phys. Conf. Series 1170, 566. doi: 10.1063/1.3246563 .
Toner, C.G., Labonte, B.J.: 1993, Direct mapping of solar acoustic power. Astrophys. J. 415, 847. doi: 10.1086/173206 .
Wiegelmann, T., Lagg, A., Solanki, S.K., Inhester, B., Woch, J.: 2005, Comparing magnetic field extrapolations with measurements of magnetic loops. Astron. Astrophys. 433, 701. doi: 10.1051/0004-6361:20042421 .
Author information
Authors and Affiliations
Corresponding author
Additional information
Helioseismology
Guest Editors: G. Houdek, H. Shibahashi, and J. Zhao
Rights and permissions
This article is published under an open access license. Please check the 'Copyright Information' section either on this page or in the PDF for details of this license and what re-use is permitted. If your intended use exceeds what is permitted by the license or if you are unable to locate the licence and re-use information, please contact the Rights and Permissions team.
About this article
Cite this article
Schunker, H., Braun, D.C. Newly Identified Properties of Surface Acoustic Power. Sol Phys 268, 349–362 (2011). https://doi.org/10.1007/s11207-010-9550-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11207-010-9550-3