Artículo
Abstract:
We have analyzed an active region which was observed in Hα (Multichannel Subtractive Double Pass Spectrograph), in UV lines (SMM/UVSP), and in X-rays (SMM/HXIS). In this active region there were only a few subflares and many small bright points visible in UV and in X-rays. Using an extrapolation based on the Fourier transform, we have computed magnetic field lines connecting different photospheric magnetic polarities from ground-based magnetograms. Along the magnetic inversion lines we find two different zones: (1) a high-shear region (>70°) where subflares occur, and (2) a low-shear region along the magnetic inversion line where UV bright points are observed. In these latter regions the magnetic topology is complex with a mixture of polarities. According to the velocity field observed in the Si IV λ1402 line and the extrapolation of the magnetic field, we notice that each UV bright point is consistent with emission from low-rising loops with downflows at both ends. We notice some hard X-ray emissions above the bright-point regions with temperatures up to 8 × 106 K, which suggests some induced reconnection due to continuous emergence of new flux. This reconnection is also enhanced by neighboring subflares.
Registro:
| Documento: | Artículo |
| Título: | Bright points and subflares in ultraviolet lines and X-rays |
| Autor: | Rovira, M.; Schmieder, B.; Démoulin, P.; Simnett, G.M.; Hagyard, M.J.; Reichmann, E.; Tandberg-Hanssen, E. |
| Filiación: | Inst. Astronomia y Fis. del Espacio, IAFE-CONICET, CC.67, Suc.28, 1428, Buenos Aires, Argentina Observatoire de Paris, URA2080, DASOP, 92195, Meudon Cedex Principal, France Inst. of Theoretical Astrophysics, Blindern, N0315, Oslo, Norway University of Birmingham, Edgbaston, Birmingham, B152TT, United Kingdom NASA Marshall Space Flight Center, Huntsville, AL 35812, United States |
| Palabras clave: | Sun: flares; Sun: UV radiation; Sun: X-rays, gamma rays |
| Año: | 1999 |
| Volumen: | 510 |
| Número: | 1 PART 1 |
| Página de inicio: | 474 |
| Página de fin: | 484 |
| Título revista: | Astrophysical Journal |
| Título revista abreviado: | Astrophys. J. |
| ISSN: | 0004637X |
| Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v510_n1PART1_p474_Rovira |
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Citas:
---------- APA ----------
Rovira, M., Schmieder, B., Démoulin, P., Simnett, G.M., Hagyard, M.J., Reichmann, E. & Tandberg-Hanssen, E. (1999) . Bright points and subflares in ultraviolet lines and X-rays. Astrophysical Journal, 510(1 PART 1), 474-484.Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v510_n1PART1_p474_Rovira [ ]
---------- CHICAGO ----------
Rovira, M., Schmieder, B., Démoulin, P., Simnett, G.M., Hagyard, M.J., Reichmann, E., et al. "Bright points and subflares in ultraviolet lines and X-rays" . Astrophysical Journal 510, no. 1 PART 1 (1999) : 474-484.Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v510_n1PART1_p474_Rovira [ ]
---------- MLA ----------
Rovira, M., Schmieder, B., Démoulin, P., Simnett, G.M., Hagyard, M.J., Reichmann, E., et al. "Bright points and subflares in ultraviolet lines and X-rays" . Astrophysical Journal, vol. 510, no. 1 PART 1, 1999, pp. 474-484.Recuperado de https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v510_n1PART1_p474_Rovira [ ]
---------- VANCOUVER ----------
Rovira, M., Schmieder, B., Démoulin, P., Simnett, G.M., Hagyard, M.J., Reichmann, E., et al. Bright points and subflares in ultraviolet lines and X-rays. Astrophys. J. 1999;510(1 PART 1):474-484.Available from: https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v510_n1PART1_p474_Rovira [ ]
