Solar faculae and floccules: spectropolarimetric and filter observations in Fe I, Ba II, and Ca II lines
Рубрика:
| 1Kostik, RI 1Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine |
| Kinemat. fiz. nebesnyh tel (Online) 2024, 40(1):65-74 |
| https://doi.org/10.15407/kfnt2024.01.065 |
| Язык: Ukrainian |
Аннотация: The results of spectropolarimetric and filter observations of a facula region located near the solar disc center in the lines of Fe I 1564.3 nm, Fe I 1565.8 nm, Ba II 455.4 nm and Ca II H 396.8 nm are discussed. The observations were obtained at the German Vacuum Tower Telescope of the Observatorio del Teide (Tenerife, Spain). Observations of the faculae region were obtained simultaneously in three spectral regions: spectropolarimetric observations of I, Q, U, V Stokes parameters of two lines of neutral iron Fe I 1564.8 nm and Fe I 1565.2 nm with a time resolution of 6 minutes 50 seconds; filter observations in 37 sections of the profile of the line of ionized barium Ba II 455.4 nm with a time resolution of 25.6 seconds; filter observations only in the center of the line of ionized calcium Ca II H 396.8 nm with a time resolution of 4.9 seconds. For the investigations we used the following observational values: 1) the power of the magnetic field at the height of the formation of a continuous spectrum near Fe I 1564.8 nm and Fe I 1565.2 nm (h ≈ –100 km) lines; 2) wave velocities at 14 heights in the atmosphere of the Sun, where radiation in Ba II 455.4 nm spectral line is formed (h ≈ 0...650 km) and calculated phase shifts between velocity fluctuations V in the photosphere at the height of radiation formation in the center of this line (h = 650 km) and velocity fluctuations at the other 13 heights; 3) the facula contrast at the height of the formation Ca II H 396.8 nm line center (h ≈ 1600 km). It is shown that: 1) the power of velocity oscillations, depending on the frequency of oscillations, varies greatly with the height in the atmosphere of the Sun. At the heights from 0 to 300 km the maximum oscillation power occurs at a frequency of 3.5 mHz. At the height of h = 650 km another maximum occurs near the frequency of 4.5 mHz, and at height of h = 1600 km the maximum oscillation power at a frequency near 1.5 mHz is quite noticeable. 2) The contrast in the center of the line Ca II H 396.8 nm (h = 650 km) does not monotonically increase with the increasing of the intensity of the photospheric magnetic field, as might be expected from general considerations. At large magnetic fields (B > 140 mT) this dependence becomes inverse. |
| Ключевые слова: faculae, magnetic fields, oscillations, spectropolarimetric observations, Sun |
References:
1. Abbasvand V., Sobotka M., Heinzel P., et al. (2020) Chromospheric heating by acoustic waves compared to radiative cooling. II. Revised grid of models. Astrophys. J. 890. 22-28. https://doi.org/10.3847/1538-4357/ab665f 2. Beck C., Khomenko E., Rezaei R., Collados M. (2009) The energy of waves in the photosphere and lower chromosphere I. Velocity statistics. Astron. and Astrophys. 507. 453-467. https://doi.org/10.1051/0004-6361/200911851 3. Berger T. E., Rouppe van der Voort L. H. M., Lfdahl M. G., et al. (2004) Solar magnetic elements at 0.1 arcsec resolution. General appearance and magnetic structure. Astron. and Astrophys. 428. 613-628. https://doi.org/10.1051/0004-6361:20040436 4. Cally P. S., Khomenko E. (2015) Fast-to-Alfvn mode conversion mediated by the Hall current. I. Cold plasma model. Astrophys. J. 814. 106-116. https://doi.org/10.1088/0004-637X/814/2/106 5. Carlsson M., Stein R. F., Nordlund ., Scharmer G. B. (2004) Observational manifestations of solar magnetoconvection: center-to-limb variation. Astrophys. J. 610. L137-L140. https://doi.org/10.1086/423305 6. Collados M., Lagg A., Daz Garca J. J., et al. (2007) Tenerife infrared polarimeter II. The physics of chromospheric plasmas, eds.: P. Heinzel, I. Dorotovi, R. J. Rutten. ASP Conf. Ser. 368. 611-616. 7. Gingerich O., Noyes R.W., Kalkofen W., Cuny Y. (1971) The Harvard-Smithsonian reference atmosphere. Solar Phys. 18. 347-365. https://doi.org/10.1007/BF00149057 8. Gonzalez-Morales P. A., Khomenko E., Vitas N., Collados M. (2020) Joint action of Hall and ambipolar effects in 3D magneto-convection simulations of the quiet Sun. I. Dissipation and generation of waves. Astron. and Astrophys. 642. A220-A237. https://doi.org/10.1051/0004-6361/202037938 9. Hirzberger J., Wiehr E. (2005) Solar limb faculae. Astron. and Astrophys. 438. 1059-1065. https://doi.org/10.1051/0004-6361:20052789 10. Keller C. U., Schssler M., Vgler A., Zakharov V. (2004) On the Origin of Solar Faculae. Astrophys. J. 607. L59-L62. https://doi.org/10.1086/421553 11. Khomenko E. (2009) Simulations of waves in sunspots. Solar-stellar dynamos as revealed by helio- and asteroseismology: GONG 2008/SOHO 21, eds.: M. Dikpati, T. Arentoft, I. Gonzlez Hernndez, C. Lindsey and F. Hill. ASP Conf. Ser. 416. 31-40. 12. Khomenko E., Cally P. S. (2012) Numerical simulations of conversion to Alfvn waves in sunspots. Astrophys. J. 746. 68-77. https://doi.org/10.1088/0004-637X/746/1/68 13. Kobel P., Solanki S. K., Borrero J. M. (2011) The continuum intensity as a function of magnetic field. I. Active region and quiet Sun magnetic elements. Astron. and Astrophys. 531. A112-A123. https://doi.org/10.1051/0004-6361/201016255 14. Kostik R. I., Khomenko E. (2007) Observations of a bright plume in solar granulations. Astron. and Astrophys. 476. 341-347. https://doi.org/10.1051/0004-6361:20077163 15. Kostik R., Khomenko E. (2012) Properties of convective motions in facular regions. Astron. and Astrophys. 545. A22-A30. https://doi.org/10.1051/0004-6361/201219534 16. Kostik R., Khomenko E. (2013) Properties of oscillatory motions in a facular region. Astron. and Astrophys. 559. A107-A116. https://doi.org/10.1051/0004-6361/201322363 17. Kostik R., Khomenko E. (2016) The possible origin of facular brightness in the solar atmosphere. Astron. and Astrophys. 589. A6-A12. https://doi.org/10.1051/0004-6361/201527419 18. Kostyk R. (2013) What are solar faculae? Kinematic and Phys. Celestial Bodies. 29(1). 32-36. https://doi.org/10.3103/S0884591313010030 19. Kostyk R. I. (2015) What mechanisms allow 5-minute oscillations in active regions of the solar surface to penetrate from the photosphere into the chromosphere? Kinematic and Phys. Celestial Bodies. 31(4). 188-192. https://doi.org/10.3103/S0884591315040054 20. Kostyk R. I. (2018) Effect of wave motions in the active region of the solar surface on convection. Kinematic and Phys. Celestial Bodies. 34(2). 82-87. https://doi.org/10.3103/S0884591318020046 21. Linsky J. L., Avrett H. E. (1970) The solar H and K lines. Publ. Astron. Soc. Pacif. 82. 485. 169-248. https://doi.org/10.1086/128904 22. Montagne M., Mueller R., Vigneau J. (1996) The photosphere of the Sun: statistical correlations between magnetic field, intensity and velocity. Astron. and Astrophys. 311. 304-310. 23. Narayan G., Scharmer G. B. (2010) Small-scale convection signatures associated with a strong plage solar magnetic field. Astron. and Astrophys. 524. A3-A18. https://doi.org/10.1051/0004-6361/201014956 24. Rajaguru S. P., Sangeetha C. R., Tripathi D. (2019) Magnetic fields and the supply of low-frequency acoustic wave energy to the solar chromospheres. Astrophys. J. 871. 155-169. https://doi.org/10.3847/1538-4357/aaf883 25. Rezaei R., Bruls J. H. M. J., Schmidt W., Beck C., Kalkofen W., Schlichenmaier R. (2008) Reversal-free Ca II H profiles: a challenge for solar chromosphere modeling in quiet inter-network. Astron. and Astrophys. 484. 503-509. https://doi.org/10.1051/0004-6361:20079050 26. Ruiz Cobo B., del Toro Iniesta J. C. (1992) Inversion of Stokes profiles. Astrophys. J. 398. 375-385. https://doi.org/10.1086/171862 27. Schroeter E. H., Soltau D., Wiehr E. (1985) The German solar telescopes at the Observatorio del Teide. Vistas in Astron. 28. 519-525. https://doi.org/10.1016/0083-6656(85)90073-X 28. Shchukina N. G., Olshevsky V. L., Khomenko E. V. (2009) The solar Ba II 4554 line as a Doppler diagnostic: NLTE analysis in 3D hydrodynamical model. Astron. and Astrophys. 506. 1393-1404. https://doi.org/10.1051/0004-6361/200912048 29. Shelyag S., Khomenko E., de Vicente ., Przybylski D. (2016) Heating of the partially ionized solar chromosphere by waves in magnetic structures. Astrophys. J. 819. L11-L16. https://doi.org/10.3847/2041-8205/819/1/L11 30. Sobotka M., Heinzel P., Svanda M., et al. (2016) Chromospheric heating by acoustic waves compared to radiative cooling. Astrophys. J. 826. 49-56. https://doi.org/10.3847/0004-637X/826/1/49 31. Solanki S. K. (1993) Small scale solar magnetic fields. An overview. Space Sci. Rev. 63. 188. https://doi.org/10.1007/BF00749277 32. Srivastava A. K., Ballester J. L., Cally P. S., et al. (2021) Chromospheric heating by MHD waves and instabilities. Manuscript submitted to J. Geophys. Research - Space Phys. eprint arXiv:2104.02010. https://doi.org/10.1029/2020JA029097 33. Stangalini M., Del Moro D., Berrilli F., Jeeries S. M. (2011) MHD wave transmission in the Sun's atmosphere. Astron. and Astrophys. 534. A65-A71. https://doi.org/10.1051/0004-6361/201117356 34. Stebbins R., Goode P. R. (1987) Waves in the solar photosphere. Solar Phys. 110. 237-253. https://doi.org/10.1007/BF00206421 35. Stodilka M. I., Kostyk R. I. (2020) Solar faculae: microturbulence as an indicator of inclined magnetic fields. Kinematic and Phys. Celestial Bodies. 36(4). 153-160. https://doi.org/10.3103/S0884591320040054 36. Stodilka M. I., Prysiazhnyi A. I., Kostyk R. I. (2019) Features of convection in the atmosphere layers of the solar facula. Kinematic and Phys. Celestial Bodies. 35. 261-270. https://doi.org/10.3103/S0884591319060059 37. Title A. M., Topka K. P., Tarbell T. D., et al. (1992) On the differences between plage and quiet Sun in the solar photosphere. Astrophys. J. 393. 782-794. https://doi.org/10.1086/171545 38. Topka K. P., Tarbell T. D., Title A. M. (1997) Properties of the smallest solar magnetic elements. II. Observations versus hot wall models of faculae. Astrophys. J. 484. 479-486. https://doi.org/10.1086/304295 39. Tritschler A., Schmidt W., Langhans K., Kentischer T. (2002) High-resolution solar spectroscopy with TESOS - Upgrade from a double to a triple system. Solar Phys. 211. 17-29. https://doi.org/10.1023/A:1022459132089