Spectropolarimetric investigation of Ellerman bomb. II. Photospheric models

1Kondrashova, NN
1Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine
Kinemat. fiz. nebesnyh tel (Online) 2016, 32(2):25-36
Start Page: Solar Physics
Language: Russian

Semiempirical photospheric models of Ellerman bomb in active region NOAA 11024 are obtained. The Stokes profiles I, Q, U, V of the photospheric lines obtained from the spectropolarimetric observations of the Ellerman bomb with the French-Italian solar telescope THEMIS (Tenerife, Spain) are used for the modeling. The models are derived from the inversion with SIR code, described by Ruiz Cobo and del Toro Iniesta [Ruiz Cobo, del Toro Iniesta // Astrophys. J.-1992.-398]. The models include two components: a thin magnetic flux tube and nonmagnetic surroundings. The optical depth dependences of the temperature, magnetic field strength, the inclination of the magnetic field vector, and line-of-sight velocity are obtained for the magnetic flux tube. Models show that the thermodynamical parameters of the Ellerman bomb photosphere differ strongly from the parameters of the quiet photosphere. The temperature in a magnetic flux tube had the inhomogeneities with height. The deviation from its values in the quiet photosphere reached 700...900 K. The models show downflows in the lower and upper photosphere. Line-of-sight velocity in the upper layers of the photosphere reached 17 km/s. The magnetic field strength in the models varied from 0.1...0.13 Т in the lower photospheric layers to 0.04...0.07 T in the upper ones. The physical state in the photosphere changed during the observations.

Keywords: Ellerman bomb, photospheric models, Stokes parameters, the Sun

1.A. N. Babin and A. N. Koval’, “Examining whisker polarization with a Ha filter,” Bull. Crimean Astrophys. Observatory 75, 48–53 (1986).

2.N. N. Kondrashova, “Spectropolarimetric investigation of Ellerman Bomb. I. Observations,” Kinematics Phys. Celestial Bodies 32, 21–32 (2016).

3.V. Archontis and A. W. Hood, “Formation of Ellerman bombs due to 3D flux emergence,” Astron. Astrophys. 508, 1469–1483 (2009).

4.N. Bello González, S. Danilovic, and F. Kneer, “On the structure and dynamics of Ellerman bombs. Detailed study of three events and modelling of Ha,” Astron. Astrophys. 557, A102 (2013).

5.A. Berlicki, P. Heinzel, and E. H. Avrett, “Photometric analysis of Ellerman bombs,” Mem. Soc. Astron. Ital. 81, 646–652 (2010).

6.M. C. M. Cheung, M. Schussler, T. D. Tarbell, and A. M. Title, “Solar surface emerging flux regions: a comparative study of radiative MHD modeling and Hinode SOT observations,” Astrophys. J. 687, 1373–1387 (2008).

7.M. D. Ding, J.-C. Henoux, and C. Fang, “Line profiles in moustaches produced by an impacting energetic particle beam,” Astron. Astrophys. 332, 761–766 (1998).

8.F. Ellerman, “Solar hydrogen "bombs ",” Astrophys. J. 46, 298–300 (1917).

9.C. Fang, Y. H. Tang, M. D. Ding, and P. F. Chen, “Spectral analysis of Ellerman bombs,” Astrophys. J. 643, 1325–1336 (2006).

10.M. K. Georgoulis, D. M. Rust, P. N. Bernasconi, and B. Schmieder, “Statistics, morphology, and energetics of Ellerman bombs,” Astrophys. J. 575, 506–528 (2002).

11.O. Gingerich, R. W. Noyes, W. Kalkofen, and Y. Cuny, “The Harvard-Smithsonian reference atmosphere,” Sol. Phys. 18, 347–365 (1971).

12.J.-C. Henoux, C. Fang, and M. D. Ding, “A possible mechanism for the Ha broad wings emission of Ellerman bombs,” Astron. Astrophys. 337, 294–298 (1998).

13.J. Hong, M. D. Ding, Y. Li, et al., “Spectral observations of Ellerman bombs band fitting with a two-cloud model,” Astrophys. J. 792, 13 (2014).

14.H. Isobe, D. Tripathi, and V. Archontis, “Ellerman bombs and jets associated with resistive flux emergence,” Astrophys. J., Lett. 657, L53–L56 (2007).

15.L. K. Kashapova, “A spectropolarimetric study of Ellerman bombs,” Astron. Rep. 46, 918–924 (2002).

16.R. Kitai, “On the mass motions and the atmospheric states of moustaches,” Sol. Phys. 87, 135–154 (1983).

17.Z. Li, C. Fang, Y. Guo, et al., “Diagnostics of Ellerman bombs with high-resolution spectral data,” Res. Astron. Astrophys. 15, 1513–1524 (2015).

18.T. Matsumoto, R. Kitai, K. Shibata, et al., “Height dependence of gas flows in an Ellerman bomb,” Publ. Astron. Soc. Japan. 60, 95–102 (2008).

19.T. Matsumoto, R. Kitai, K. Shibata, et al., “Cooperative observation of Ellerman bombs between the Solar Optical Telescope aboard Hinode and Hida/Domless Solar Telescope,” Publ. Astron. Soc. Japan. 60, 577–584 (2008).

20.C. J. Nelson, E. M. Scullion, J. G. Doyle, et al., “Small-scale structuring of Ellerman bombs at the solar limb,” Astrophys. J., 798, 19 (2015).

21.C. J. Nelson, S. Shelyag, M. Mathioudakis, et al., “Ellerman Bombs–evidence for magnetic reconnection in the lower solar atmosphere,” Astrophys. J. 779, 125 (2013).

22.E. Pariat, G. Aulanier, B. Schmieder, et al., “Resistive emergence of undulatory flux tubes,” Astrophys. J. 614, 1099–1112 (2004).

23.E. Pariat, S. Masson, and G. Aulanier, “Current buildup in emerging serpentine flux tubes,” Astrophys. J. 701, 1911–1921 (2009).

24.E. Pariat, S. Masson, and G. Aulanier, “3D MHD simulation of current intensification along serpentine emerging magnetic fields,” Astron. Soc. Pac. Conf. Ser. 455, 177 (2012).

25.E. Pariat, B. Schmieder, A. Berlicki, et al., “Spectrophotometric analysis of Ellerman bombs in the Ca II, Ha, and UV range,” Astron. Astrophys. 473, 279–289 (2007).

26.E. N. Parker, “The dynamical state of the interstellar gas and field,” Astrophys. J. 145, 811–833 (1966).

27.J. Qiu, M. D. Ding, H. Wang, et al., “Ultraviolet and Ha emission in Ellerman bombs,” Astrophys. J., Lett. 544, L157–L161 (2000).

28.B. Ruiz Cobo and J. C. del Toro Iniesta, “Inversion of Stokes profiles,” Astrophys. J. 398, 375–385 (1992).

29.D. M. Rust and S. L. Keil, “A search for polarization in Ellerman bombs,” Sol. Phys. 140, 55–65 (1992).

30.R. J. Rutten, G. J. M. Vissers, L. H. M. Rouppe van der Voort, et al., “Ellerman bombs: fallacies, fads, usage,” J. Phys.: Conf. Ser. 440, i. 012007 (2013).

31.B. Schmieder, E. Pariat, G. Aulanier, et al., “Flare Genesis Experiment: magnetic topology of Ellerman bombs,” in Solar Variability: From Core to Outer Frontiers. (Proc. The 10th European Solar Physics Meeting, Prague, Czech Republic, Sep. 9–14, 2002), Ed. by A. Wilson (ESA, Noordwijk, 2002), Vol. 2, pp. 911–914.

32.B. Schmieder, D. M. Rust, M. K. Georgoulis, et al., “Emerging flux and the heating of coronal loops,” Astrophys. J. 601, 530–545 (2004).

33.A. B. Severny, “Fine structure in solar spectra,” Observatory 76, 241–242 (1956).

34.N. Shchukina and J. Trujillo Bueno, “The iron line formation problem in three-dimensional hydrodynamic models of solar-like photospheres,” Astrophys. J. 550, 970–990 (2001).

35.H. Socas-Navarro, V. Martínez Pillet, D. Elmore, et al., “Spectro-polarimetric observations and non-LTE modeling of Ellerman bombs,” Sol. Phys. 235, 75–86 (2006).

36.G. Stellmacher and E. Wiehr, “Modelling the moustache phenomenon in network regions,” Astron. Astrophys. 251, 675–679 (1991).

37.G. Valori, L. M. Green, P. Demoulin, et al., “Nonlinear force-free extrapolation of emerging flux with a global twist and serpentine fine structures,” Sol. Phys. 278, 73–97 (2012).

38.G. J. M. Vissers, L. H. M. Rouppe van der Voort, and R. J. Rutten, “Ellerman bombs at high resolution. II. Triggering, visibility and effect on upper atmosphere,” Astrophys. J. 774, 32 (2013).

39.H. Watanabe, R. Kitai, K. Okamoto, et al., “Spectropolarimetric observation of an emerging flux region: triggering mechanisms of Ellerman bombs,” Astrophys. J. 684, 736–746 (2008).

40.H. Watanabe, G. Vissers, R. Kitai, et al., “Ellerman bombs at high resolution. I. Morphological evidence for photospheric reconnection,” Astrophys. J. 736, 71 (2011).

41.X.-Y. Xu, C. Fang, M. D. Ding, and D-H. Gao, “Numerical simulations of magnetic reconnection in the lower solar atmosphere,” Res. Astron. Astrophys. 11, 225–236 (2011).