Artículo
Abstract:
In a previous work we developed a stationary proton-electron MHD model of the solar corona, suitable for the minimum-activity epochs. In the present work, we use empirically derived information from the past solar minimum for the oxygen parameters (temperatures and outflow velocity) to develop an oxygen model in the frame of our previous model. Solar and Heliospheric Observatory UVCS observations of past minimum coronal streamers in the O VI λ1032 and O VI λ1037 lines have revealed that oxygen abundances are very much depleted within the stable closed-field regions of the quiescent streamers. This characteristic appears as a relatively dark region, often seen in the core of the quiescent equatorial streamers when imaged in oxygen lines. Using the oxygen abundance as a free parameter, we compute the expected O VI line emissivities from our models and synthesize images considering the projection effects in detail. We find here that, in order to obtain oxygen images with dark streamer cores similar to those observed, very low element abundances have to be assumed. The required depletion factors are lower than previous estimates that do not account for projection effects, which is especially important at 1.75 R⊙ and higher. © 2005. The American Astronomical Society. All rights reserved.
Registro:
| Documento: | Artículo |
| Título: | Oxygen abundance in coronal streamers |
| Autor: | Vásquez, A.M.; Raymond, J.C. |
| Filiación: | Inst. Astronomia y Fis. del Espacio, CC 67-Suc 28, (1428) Ciudad de Buenos Aires, Argentina Harvard-Smithsonian Ctr. Astrophys., MS 15, 60 Garden Street, Cambridge, MA 02138, United States Department of Physics, University of Buenos Aires, Argentina |
| Palabras clave: | Solar wind; Sun: abundances; Sun: corona; Sun: UV radiation |
| Año: | 2005 |
| Volumen: | 619 |
| Número: | 2 I |
| Página de inicio: | 1132 |
| Página de fin: | 1141 |
| DOI: | http://dx.doi.org/10.1086/426776 |
| Título revista: | Astrophysical Journal |
| Título revista abreviado: | Astrophys. J. |
| ISSN: | 0004637X |
| Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v619_n2I_p1132_Vasquez |
Referencias:
- Antonucci, E., Dodero, M.A., Giordano, S., Krishnakumar, V., Noci, G., (2004) A&A, 416, p. 749
- Bame, S.J., McComas, D.J., Barraclough, B.L., Phillips, J.L., Sofaly, K.J., Chavez, J.C., Goldstein, B.E., Sakurai, R.K., (1992) A&AS, 92, p. 237
- Chen, Y., Hu, Y.Q., (2001) Sol. Phys., 199, p. 371
- Cranmer, S.R., (1999) ApJ, 511, p. 481
- Dodero, M.A., Antonucci, E., Giordano, S., Martin, R., (1998) Sol. Phys., 183, p. 77
- Esser, R., Edgar, R.J., Brickhouse, N.S., (1998) ApJ, 498, p. 448
- Feldman, U., (1992) Phys. Scr., 46, p. 202
- Feldman, U., Doschek, G.A., Schule, U., Wilhelm, K., (1999) ApJ, 518, p. 500
- Frazin, R.A., (2002), Ph.D. thesis, Univ. Illinois, Urbana-Champaign; Gibson, S.E., Fludra, A., Bagenal, F., Biesecker, D., Del Zanna, G., Bromage, B., (1999) J. Geophys. Res., 104, p. 9691
- Giordano, S., Antonucci, E., Dodero, M.A., (2000) Adv. Space Res., 25, p. 1927
- Guhathakurta, M., Fludra, A., Gibson, S.E., Biesecker, D., Fisher, R., (1999) J. Geophys. Res., 104, p. 9801
- Habbal, S.R., Woo, R., Vial, J.-C., (2001) Space Sci. Rev., 97, p. 5
- Hovestadt, D., (1995) Sol. Phys., 162, p. 441
- Ko, Y.-K., Fisk, L.A., Geiss, J., Gloeckler, G., Guhatakurtha, M., (1997) Sol. Phys., 171, p. 345
- Ko, Y.-K., Raymond, J., Li, J., Ciaravella, A., Michels, J., Fineschi, S., Wu, R., (2002) ApJ, 578, p. 979
- Kohl, J.L., (1995) Sol. Phys., 162, p. 313
- Marocchi, D., Antonucci, E., Giordano, S., (2001) Ann. Geophys., 19, p. 135
- McComas, D.J., Bame, S.J., Barker, P., Feldman, W.C., Phillips, J.L., Riley, P., Griffee, J.W., (1998) Space Sci. Rev, 86, p. 563
- Meyer, J.P., (1985) ApJS, 57, p. 151
- (1985) ApJS, 57, p. 173
- Noci, G., Maccari, L., (1999) A&A, 341, p. 275
- Noci, G., (1997) Proc. 5th SOHO Workshop: the Corona and Solar Wind Near Minimum Activity, p. 75. , ed. A. Wilson (ESA SP-404; Noordwijk: ESA)
- Parenti, S., Bromage, B.J.I., Poletto, G., Noci, G., Raymond, J.C., Bromage, G.E., (2000) A&A, 363, p. 800
- Raymond, J.C., Suleiman, R., Van Ballegooijen, A., Kohl, J., (1997) Proc. 31st ESLAB Symp., Correlated Phenomena at the Sun, in the Heliosphere and in Geospace, p. 383. , ed. A. Wilson (ESA SP-415; Noordwijk: ESA)
- Raymond, J.C., (1997) Sol. Phys., 175, p. 645
- Strachan, L., Panasyuk, A.V., Dobrzycka, D., Kohl, J.L., Noci, G., Gibson, S.E., Biesecker, D.A., (2000) J. Geophys. Res., 105, p. 2345
- Strachan, L., Suleiman, R., Panasyuk, A.V., Biesecker, D.A., Kohl, J.L., (2002) ApJ, 571, p. 1008
- Suess, S.T., Nerney, S.F., (1999) Proc. 9th European Meeting on Solar Physics, Magnetic Fields and Solar Processes, p. 1101. , ed. A. Wilson (ESA SP-44; Noordwijk: ESA)
- (2002) ApJ, 565, p. 1275
- Uzzo, M., Ko, Y.-K., Raymond, J.C., Wurz, P., Ipavich, F.M., (2003) ApJ, 585, p. 1062
- Vásquez, A.M., (2002), Ph.D. thesis, Univ. Buenos Aires; Vásquez, A.M., Van Ballegooijen, A.A., Raymond, J.C., (1999) AIP Conf. Proc., 471, p. 243. , Solar Wind Nine: Proc. Ninth Int. Solar Wind Conf., ed. S. R. Habbal et al. (Woodbury: AIP)
- (2003) ApJ, 598, p. 1361
- Wang, Y.-M., (1994) ApJ, 437, pp. L67
Citas:
---------- APA ----------
Vásquez, A.M. & Raymond, J.C. (2005) . Oxygen abundance in coronal streamers. Astrophysical Journal, 619(2 I), 1132-1141.http://dx.doi.org/10.1086/426776
---------- CHICAGO ----------
Vásquez, A.M., Raymond, J.C. "Oxygen abundance in coronal streamers" . Astrophysical Journal 619, no. 2 I (2005) : 1132-1141.http://dx.doi.org/10.1086/426776
---------- MLA ----------
Vásquez, A.M., Raymond, J.C. "Oxygen abundance in coronal streamers" . Astrophysical Journal, vol. 619, no. 2 I, 2005, pp. 1132-1141.http://dx.doi.org/10.1086/426776
---------- VANCOUVER ----------
Vásquez, A.M., Raymond, J.C. Oxygen abundance in coronal streamers. Astrophys. J. 2005;619(2 I):1132-1141.http://dx.doi.org/10.1086/426776
