Abstract
The results of analysis of spectral observations of two Ellerman bombs (EB-1 and EB-2), which were formed and have evolved in the area of emerging magnetic flux in active region (AR) NOAA 11024, are presented. Spectral data with high spatial and temporal (approximately 3 s) resolution were obtained using the THEMIS French–Italian solar telescope on July 4, 2009. The observation duration was 20 min. The spectral region of λ ≈ 630 nm with photospheric lines forming in a wide altitude range (neutral iron lines Fe I λ 630.15, 630.25, and 630.35 nm and titanium line Ti I λ 630.38 nm) was examined. The brightness of EB-1 decreased in the process of observations, while the brightness of EB-2 increased. The profiles of metal lines determined at different stages of EBs evolution were asymmetric. This asymmetry was more pronounced in lines that had formed in the lower photospheric layers and often had profiles with several components. The half-width of profiles increased with a reduction in their central depth. The variation of central intensities of Fraunhofer lines in the spectra of EBs and their vicinity at different stages of EB evolution was analyzed. The EBs formed in intergranular lanes. An increase in the core intensity of all the studied photospheric lines was correlated spatially with an increase in the wings intensity of the Hα line. Brightness variations at all photospheric levels were of an oscillatory nature with an interval of 1–5 min. The observed temporal variations of Fraunhofer line intensities in the spectra of the studied AR section suggest that the emergence of the new magnetic flux induced consecutive magnetic reconnections in the EB-1 region, the excitation propagated along a magnetic loop and initiated the formation of EB-2, and the two bombs then evolved as a physically connected pair.
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References
E. A. Gurtovenko and R. I. Kostyk, Fraunhofer Spectrum and a Solar Force System for Oscillators (Naukova Dumka, Kiev, 1989) [in Russian].
N. N. Kondrashova, “Spectropolarimetric investigation of an Ellerman bomb: 1. Observations,” Kinematics Phys. Celestial Bodies 32, 13–22 (2016).
R. I. Kostyk and N. G. Shchukina, “Five-minute oscillations and the fine structure of the solar photosphere. I,” Kinematika Fiz. Nebesnykh Tel 15, 25–37 (1999).
M. N. Pasechnik, “Plasma motions in the solar loop of emerging magnetic flux,” Kinematics Phys. Celestial Bodies 30, 161–172 (2014).
M. N. Pasechnik, “Spectral study of a pair of Ellerman bombs,” Kinematics Phys. Celestial Bodies 32, 55–69 (2016).
A. B. Severnyi, “Investigation of the fine structure of the emission of active formations and nonstationary processes on the Sun,” Izv. Krym. Astrofiz. Obs. 17, 129–161 (1957).
J. M. Beckers, A Table of Zeeman Multiplets (Air Force Cambridge Research Laboratories, Bedford, MA, 1969), in Ser.: Physical Science Research Papers, Vol. 371.
A. Berlicki, P. Heinzel, and E. H. Avrett, “Photometric analysis of Ellerman bombs,” Mem. Soc. Astron. Ital. 81, 646–652 (2010).
L. Bharti, Th. Rimmele, R. Jain, et al., “Detection of opposite polarities in a sunspot light bridge: evidence of low-altitude magnetic reconnection,” Mon. Not. R. Astron. Soc. 37, 1291–1295 (2007).
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).
F. Ellerman, “Solar hydrogen “bombs”,” Astrophys. J. 46, 298–301 (1917).
A. J. Engell, M. Siarkowski, M. Gryciuk, et al., “Flares and their underlying magnetic complexity,” Astrophys. J. 726, 12–20 (2011).
C. Fang, Y. H. Tang, Z. Xu, et al., “Spectral analysis of Ellerman bombs,” Astrophys. J. 643, 1325–1336 (2006).
M. K. Georgoulis, D. M. Rust, P. N. Bernasconi, et al., “Statistics, morphology, and energetics of Ellerman Bomb,” Astrophys. J. 575, 506–528 (2002).
S. L. Guglielmino, L. R. Bellot Rubio, F. Zuccarello, et al., “Multiwavelength observations of small-scale reconnection events triggered by magnetic flux emergence in the solar atmosphere,” Astrophys. J. 724, 1083–1098 (2010).
Y. Hashimoto, R. Kitai, K. Ichimoto, et al., “Internal fine structure of Ellerman bombs,” Pubis Astron. Soc. Jpn. 62, 879–891 (2010).
M. Herlender and A. Berlicki, “Multi-wavelength analysis of Ellerman bomb light curves,” Cent. Eur. Astrophys. Bull. 35, 181–186 (2011).
D. B. Jess, M. Mathioudakis, P. K. Browning, et al., “Microflare activity driven by forced magnetic reconnection,” Astrophys. J. Lett. 712, L111–L115 (2010).
L. K. Kashapova, “A spectropolarimetric study of Ellerman bombs,” Astron. Rep. 46, 918–924 (2002).
R. Kitai, “On the mass motions and the atmospheric states of moustaches,” Sol. Phys. 87, 135–154 (1983).
R. Kitai, “Ellerman bomb as a manifestation of chromospheric fine scale activity,” in Proc. 5th Hinode Science Meeting, Cambridge, MA, Oct. 10–15, 2011 (Astronomical Society of the Pacific, San Francisco, CA, 2012), in Ser.: ASP Conference Series, Vol. 456, p. 81.
N. N. Kondrashova, M. N. Pasechnik, S. N. Chornogor, et al., “Atmosphere dynamics of the active region NOAA 11024,” Sol. Phys. 284, 499–513 (2013).
H. Kurokawa, I. Kawaguchi, Y. Funakoshi, et al., “Morphological and evolutional features of Ellerman bombs,” Sol. Phys. 79, 77–84 (1982).
T. Matsumoto, R. Kitai, K. Shibata, et al., “Height dependence of gas flows in an Ellerman bomb,” Pubis Astron. Soc. Jpn. 60, 95–102 (2008).
T. Matsumoto, R. Kitai, K. Shibata, et al., “Cooperative observation of Ellerman bombs between the Solar Optical Telescope aboard Hinode and Hida/Domeless Solar Telescope,” Pubis Astron. Soc. Jpn. 60, 577–584 (2008).
C. J. Nelson, J. G. Doyle, R. Erdélyi, et al., “Statistical analysis of small Ellerman bomb events,” Sol. Phys. 283, 307–323 (2013).
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).
C. J. Nelson, S. Shelyag, M. Masthioudakis, et al., “Ellerman bombs — Evidence for magnetic reconnection in the lower solar atmosphere,” Astrophys. J. 779, 125 (2013).
E. Pariat, B. Schmieder, A. Berlicki, et al., “Spectrophotometric analysis of Ellerman bombs in the CaII, Ha, and UV range,” Astron. Astrophys. 473, 279–289 (2007).
E. Pariat, B. Schmieder, A. Berlicki, et al., “Spectrophotometry of Ellerman bombs with THEMIS,” in Proc. The Physics of Chromospheric Plasmas, Coimbra, Portugal, Oct. 9–13, 2006, Ed. by P. Heinzel, I. Dorotovi., and R. J. Rutten (Astronomical Society of the Pacific, San Francisco, CA, 2007), in Ser.: ASP Conference Series, Vol. 368, 253–258 (2007).
J. Qiu, M. D. Ding, H. Wang, et al., “Ultraviolet and Ha emission in Ellerman bombs,” Astrophys. J. Lett. 544, L157–L161 (2000).
A. Read, M. Mathioudakis, J. G. Doyle, et al., “Magnetic flux cancellation in Ellerman bombs,” Astrophys. J. 823, 110 (2016).
R. J. Rutten, L. H. M. Rouppe van der Voort and G. J. M. Vissers, “Ellerman bombs at high resolution. IV. Visibility in Na I and Mg I,” Astrophys. J. 808, 133 (2015).
R. J. Rutten, “Ha features with hot onsets I. Ellerman bombs,” Astron. Astrophys. 590, A124 (2016).
H. Socas-Navarro, V. Martinez Pillet, D. Elmore, et al., “Spectro-polarimetric observations and non-LTE modeling of Ellerman bombs,” Sol. Phys. 235, 75–86 (2006).
H. Socas-Navarro and H. Uitenbroek, “On the diagnostic potential of Ha for chromospheric magnetism,” Astrophys. J. Lett. 603, L129–L132 (2004).
G. Valori, L. M. Green, P. Demouli, et al., “Nonlinear force-free extrapolation of emerging flux with a global twist and serpentine fine structures,” Sol. Phys. 278, 73–97 (2012).
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).
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).
H. Watanabe, G. Vissers, R. Kitai, et al., “Ellerman bombs at high resolution: 1. Morphological evidence for photospheric reconnection,” Astrophys. J. 736, 71 (2011).
Th. G. Zachariadis, C. E. Alissandrakis and G. Banos, “Observations of Ellerman bombs in Ha,” Sol. Phys. 108, 227–236 (1987).
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Original Russian Text © M.N. Pasechnik, 2018, published in Kinematika i Fizika Nebesnykh Tel, 2018, Vol. 34, No. 2, pp. 25–45.
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Pasechnik, M.N. Spectral Study of Ellerman Bombs. Photosphere. Kinemat. Phys. Celest. Bodies 34, 68–81 (2018). https://doi.org/10.3103/S0884591318020071
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DOI: https://doi.org/10.3103/S0884591318020071