Abstract
Magnetic field diagnostics of the transition region from the chromosphere to the corona faces us with the problem that one has to apply extreme-ultraviolet (EUV) spectro-polarimetry. While for the coronal diagnostics techniques already exist in the form of infrared coronagraphy above the limb and radio observations on the disk, one has to investigate EUV observations for the transition region. However, so far the success of such observations has been limited, but various current projects aim to obtain spectro-polarimetric data in the extreme UV in the near future. Therefore it is timely to study the polarimetric signals we can expect from these observations through realistic forward modeling.
We employ a 3D magneto-hydrodynamic (MHD) forward model of the solar corona and synthesize the Stokes I and Stokes V profiles of C iv (1548 Å). A signal well above 0.001 in Stokes V can be expected even if one integrates for several minutes to reach the required signal-to-noise ratio, and despite the rapidly changing intensity in the model (just as in observations). This variability of the intensity is often used as an argument against transition region magnetic diagnostics, which requires exposure times of minutes. However, the magnetic field is evolving much slower than the intensity, and therefore the degree of (circular) polarization remains rather constant when one integrates in time. Our study shows that it is possible to measure the transition region magnetic field if a polarimetric accuracy on the order of 0.001 can be reached, which we can expect from planned instrumentation.
Coronal Magnetometry
Guest Editors: S. Tomczyk, J. Zhang, and T.S. Bastian
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Bingert, S., Peter, H.: 2011, Intermittent heating in the solar corona employing a 3D MHD model. Astron. Astrophys. 530, A112.
Bingert, S., Peter, H.: 2013, Nanoflare heating in an active region 3D MHD coronal model. Astron. Astrophys. 550, A30.
Brković, A., Peter, H.: 2004, Statistical comparison of transition region blinkers and explosive events. Astron. Astrophys. 422, 709 – 716.
Centeno, R., Trujillo Bueno, J., Asensio Ramos, A.: 2010, On the magnetic field of off-limb spicules. Astrophys. J. 708, 1579 – 1584.
De Rosa, M.L., Schrijver, C.J., Barnes, G., Leka, K.D., Lites, B.W., Aschwanden, M.J., Amari, T., Canou, A., McTiernan, J.M., Régnier, S., Thalmann, J.K., Valori, G., Wheatland, M.S., Wiegelmann, T., Cheung, M.C.M., Conlon, P.A., Fuhrmann, M., Inhester, B., Tadesse, T.: 2009, A critical assessment of nonlinear force-free field modeling of the solar corona for active region 10953. Astrophys. J. 696, 1780 – 1791.
Dere, K.P., Landi, E., Mason, H.E., Monsignori Fossi, B.C., Young, P.R.: 1997, CHIANTI–an atomic database for emission lines. Astron. Astrophys. Suppl. 125, 149 – 173.
Gudiksen, B., Nordlund, Å.: 2002, Bulk heating and slender magnetic loops in the solar corona. Astrophys. J. Lett. 572, L113 – L116.
Gudiksen, B., Nordlund, Å.: 2005a, An ab initio approach to the solar coronal heating problem. Astrophys. J. 618, 1020 – 1030.
Gudiksen, B., Nordlund, Å.: 2005b, An ab initio approach to solar coronal loops. Astrophys. J. 618, 1031 – 1038.
Hagyard, M.J., Teuber, D., West, E.A., Tandberg-Hanssen, E., Henze, W. Jr., Beckers, J.M., Bruner, M., Hyder, C.L., Woodgate, B.E.: 1983, Vertical gradients of sunspot magnetic fields. Solar Phys. 84, 13 – 31.
Hansteen, V.H., Hara, H., De Pontieu, B., Carlsson, M.: 2010, On redshifts and blueshifts in the transition region and corona. Astrophys. J. 718, 1070 – 1078.
Harrison, R.A., Lang, J., Brooks, D.H., Innes, D.E.: 1999, A study of extreme ultraviolet blinker activity. Astron. Astrophys. 351, 1115 – 1132.
Harrison, R.A., Harra, L.K., Brković, A., Parnell, C.E.: 2003, A study of the unification of quiet-Sun transient-event phenomena. Astron. Astrophys. 409, 755 – 764.
Henze, W. Jr., Tandberg-Hanssen, E., Hagyard, M.J., West, E.A., Woodgate, B.E., Shine, R.A., Beckers, J.M., Bruner, M., Hyder, C.L., West, E.A.: 1982, Observations of the longitudinal magnetic field in the transition region and photosphere of a sunspot. Solar Phys. 81, 231 – 244.
Kobayashi, K., Kano, R., Trujillo-Bueno, J., Ramos, A.A., Bando, T., Belluzzi, L., Carlsson, M., De Pontieu, R.C.B., Hara, H., Ichimoto, K., Ishikawa, R., Katsukawa, Y., Kubo, M., Sainz, R.M., Narukage, N., Sakao, T., Stepan, J., Suematsu, Y., Tsuneta, S., Watanabe, H., Winebarger, A.: 2012, The chromospheric Lyman-alpha SpectroPolarimeter: CLASP. In: Golub, L., De Moortel, I., Shimizu, T. (eds.) Fifth Hinode Science Meeting CS-456, 233 – 240.
Lin, H., Penn, M.J., Tomczyk, S.: 2000, A new precise measurement of the coronal magnetic field strength. Astrophys. J. 541, L83 – L86.
Lites, B.W.: 2001, Space-based instrumentation for inference of the solar magnetic field. In: Mathys, G., Solanki, S.K., Wickramasinghe, D.T. (eds.) Magnetic Fields Across the Hertzsprung-Russell Diagram CS-248, 553 – 562.
Peter, H.: 1999, Analysis of transition-region emission line profiles from full-disk scans of the Sun using the sumer instrument on SOHO. Astrophys. J. 516, 490 – 504.
Peter, H.: 2000, Multi-component structure of solar and stellar transition regions. Astron. Astrophys. 360, 761 – 776.
Peter, H.: 2001, On the nature of the transition region from the chromosphere to the corona of the Sun. Astron. Astrophys. 374, 1108 – 1120.
Peter, H., Bingert, S.: 2012, Constant cross section of loops in the solar corona. Astron. Astrophys. 548, A1.
Peter, H., Brković, A.: 2003, Explosive events and transition region blinkers: time variability of non-Gaussian quiet Sun EUV spectra. Astron. Astrophys. 403, 287 – 295.
Peter, H., Judge, P.G.: 1999, On the Doppler shifts of solar UV emission lines. Astrophys. J. 522, 1148 – 1166.
Peter, H., Gudiksen, B., Nordlund, Å.: 2004, Coronal heating through braiding of magnetic field lines. Astrophys. J. Lett. 617, L85 – L88.
Peter, H., Gudiksen, B., Nordlund, Å.: 2006, Forward modeling of the corona of the Sun and solar-like stars: from a three-dimensional magnetohydrodynamic model to synthetic extreme-ultraviolet spectra. Astrophys. J. 638, 1086 – 1100.
Peter, H., Abbo, L., Andretta, V., Auchère, F., Bemporad, A., Berrilli, F., Bommier, V., Braukhane, A., Casini, R., Curdt, W., Davila, J., Dittus, H., Fineschi, S., Fludra, A., Gandorfer, A., Griffin, D., Inhester, B., Lagg, A., Degl’Innocenti, E.L., Maiwald, V., Sainz, R.M., Pillet, V.M., Matthews, S., Moses, D., Parenti, S., Pietarila, A., Quantius, D., Raouafi, N.-E., Raymond, J., Rochus, P., Romberg, O., Schlotterer, M., Schühle, U., Solanki, S., Spadaro, D., Teriaca, L., Tomczyk, S., Bueno, J.T., Vial, J.-C.: 2012, Solar magnetism eXplorer (SolmeX). Exploring the magnetic field in the upper atmosphere of our closest star. Exp. Astron. 33, 271 – 303.
Schrijver, C.J., Zwaan, C.: 2000, Solar and Stellar Magnetic Activity, Cambridge Univ. Press, Cambridge.
Stenflo, J.O.: 1994, Solar Magnetic Fields, Kluwer, Dordrecht.
Trujillo Bueno, J., Štěpán, J., Casini, R.: 2011, The Hanle effect of the hydrogen Lyα line for probing the magnetism of the solar transition region. Astrophys. J. Lett. 738, L11.
Štěpán, J., Trujillo Bueno, J., Carlsson, M., Leenaarts, J.: 2012, The Hanle effect of Lyα in a magnetohydrodynamic model of the solar transition region. Astrophys. J. Lett. 758, L43.
West, E.A., Porter, J.G., Davis, J.M., Gary, G.A., Noble, M.W., Lewis, M., Thomas, R.J.: 2004, The Marshall Space Flight Center solar ultraviolet magnetograph. In: Hasinger, G., Turner, M.J.L. (eds.) Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series 5488, 801 – 812.
West, E., Cirtain, J., Kobayashi, K., Davis, J., Gary, A., Adams, M.: 2011, MgII linear polarization measurements using the MSFC solar ultraviolet magnetograph. In: Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series 8160, 816010.
White, S.M.: 2005, Radio measurements of coronal magnetic fields. In: Chromospheric and Coronal Magnetic Fields SP-596, ESA, Noordwijk, CDROM 10.1.
Wilhelm, K., Curdt, W., Marsch, E., Schühle, U., Lemaire, P., Gabriel, A., Vial, J.-C., Grewing, M., Huber, M.C.E., Jordan, S.D., Poland, A.I., Thomas, R.J., Kühne, M., Timothy, J.G., Hassler, D.M., Siegmund, O.H.W.: 1995, SUMER – solar ultraviolet measurements of emitted radiation. Solar Phys. 162, 189 – 231.
Woodgate, B.E., Brandt, J.C., Kalet, M.W., Kenny, P.J., Tandberg-Hanssen, E.A., Bruner, E.C., Beckers, J.M., Henze, W., Knox, E.D., Hyder, C.L.: 1980, The ultraviolet spectrometer and polarimeter on the solar maximum mission. Solar Phys. 65, 73 – 90.
Young, P.R., Del Zanna, G., Landi, E., Dere, K.P., Mason, H.E., Landini, M.: 2003, CHIANTI – an atomic database for emission lines. VI. Proton rates and other improvements. Astrophys. J. Suppl. 144, 135 – 152.
Zacharias, P., Bingert, S., Peter, H.: 2011a, Ejection of cool plasma into the hot corona. Astron. Astrophys. 532, A112.
Zacharias, P., Bingert, S., Peter, H.: 2011b, Investigation of mass flows in the transition region and corona in a three-dimensional numerical model approach. Astron. Astrophys. 531, A97.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2013 Springer Science+Business Media Dordrecht
About this chapter
Cite this chapter
Peter, H. (2013). Magnetic Field Diagnostics and Spatio-Temporal Variability of the Solar Transition Region. In: Tomczyk, S., Zhang, J., Bastian, T. (eds) Coronal Magnetometry. Springer, New York, NY. https://doi.org/10.1007/978-1-4939-2038-9_5
Download citation
DOI: https://doi.org/10.1007/978-1-4939-2038-9_5
Publisher Name: Springer, New York, NY
Print ISBN: 978-1-4939-2037-2
Online ISBN: 978-1-4939-2038-9
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)