Abstract
Measurements of the ionized Ca ii K line are one of the major resources for long-term studies of solar and stellar activity. They also play a critical role in many studies related to solar irradiance variability, particularly as a ground-based proxy to model the solar ultraviolet flux variation that may influence the Earth’s climate. Full disk images of the Sun in Ca ii K have been available from various observatories for more than 100 years and latter synoptic Sun-as-a-star observations in Ca ii K began in the early 1970s. One of these instruments, the Integrated Sunlight Spectrometer (ISS) has been in operation at Kitt Peak (Arizona) since late 2006. The ISS takes daily observations of solar spectra in nine spectra bands, including the Ca ii K and H lines. We describe recent improvements in data reduction of Ca ii K observations, and present time variations of nine parameters derived from the profile of this spectral line.
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Buccino, A.P., Díaz, R.F., Luoni, M.L., Abrevaya, X.C., Mauas, P.J.D.: 2011, Long-term chromospheric activity in southern M dwarfs: Gl 229 a and Gl 752 A. Astron. J. 141, 34. doi: 10.1088/0004-6256/141/2/34 .
Donahue, R.A., Keil, S.L.: 1995, The solar surface differential rotation from disk-integrated chromospheric fluxes. Solar Phys. 159, 53 – 62. doi: 10.1007/BF00733031 .
Foukal, P.: 2002, A comparison of variable solar total and ultraviolet irradiance outputs in the 20th century. Geophys. Res. Lett. 29(23), 2089. doi: 10.1029/2002GL015474 .
Foukal, P., Bertello, L., Livingston, W.C., Pevtsov, A.A., Singh, J., Tlatov, A.G., Ulrich, R.K.: 2009, A century of solar Ca ii measurements and their implication for solar UV driving of climate. Solar Phys. 255, 229 – 238. doi: 10.1007/s11207-009-9330-0 .
Giampapa, M.S., Hall, J.C., Radick, R.R., Baliunas, S.L.: 2006, A survey of chromospheric activity in the solar-type stars in the open cluster M67. Astrophys. J. 651, 444 – 461. doi: 10.1086/507624 .
Grunhut, J.H., Wade, G.A., Hanes, D.A., Alecian, E.: 2010, Systematic detection of magnetic fields in massive, late-type supergiants. Mon. Not. Roy. Astron. Soc. 408, 2290 – 2297. doi: 10.1111/j.1365-2966.2010.17275.x .
Hall, J.C., Lockwood, G.W.: 1998, The solar activity cycle. I. Observations of the end of cycle 22, 1993 September – 1997 February. Astrophys. J. 493, 494 – 504. doi: 10.1086/305116 .
Hall, J.C., Lockwood, G.W., Skiff, B.A.: 2007, The activity and variability of the Sun and sun-like stars. I. Synoptic Ca ii H and K observations. Astron. J. 133, 862 – 881. doi: 10.1086/510356 .
Hasler, K., Rüdiger, G., Staude, J.: 2002, Signature of differential rotation in solar disk-integrated chromospheric line emission. Astron. Nachr. 323, 123 – 128.
Kane, R.P.: 2002, Evolutions of various solar indices around sunspot maximum and sunspot minimum years. Ann. Geophys. 20, 741 – 755. doi: 10.5194/angeo-20-741-2002 .
Keil, S.L., Worden, S.P.: 1984, Variations in the solar calcium K line 1976 – 1982. Astrophys. J. 276, 766 – 781. doi: 10.1086/161663 .
Keil, S.L., Henry, T.W., Fleck, B.: 1998, NSO/AFRL/Sac peak K-line monitoring program. In: Balasubramaniam, K.S., Harvey, J., Rabin, D. (eds.) Synoptic Solar Physics CS-140, 301 – 309.
Keller, C.U., Harvey, J.W., Giampapa, M.S.: 2003a, SOLIS: an innovative suite of synoptic instruments. In: Keil, S.L., Avakyan, S.V. (eds.) Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, 4853, 194 – 204.
Keller, C.U., Harvey, J.W., The Solis Team: 2003b, The SOLIS vector-spectromagnetograph. In: Trujillo-Bueno, J., Sanchez Almeida, J. (eds.) Astronomical Society of the Pacific Conference Series, 307, 13 – 22.
Lenz, L.F., Reiners, A., Kürster, M.: 2010, A search for star – planet interactions in chromospheric lines. ArXiv:1012.1720 .
Livingston, W., Milkey, R., Slaughter, C.: 1977, Solar luminosity variation. I – C i 5380 as a temperature indicator and a search for global oscillations. Astrophys. J. 211, 281 – 287. doi: 10.1086/154929 .
Livingston, W., Wallace, L., White, O.R., Giampapa, M.S.: 2007, Sun-as-a-star spectrum variations 1974 – 2006. Astrophys. J. 657, 1137 – 1149. doi: 10.1086/511127 .
Livingston, W., White, O.R., Wallace, L., Harvey, J.: 2010, Sun-as-a-star, chromospheric lines, 1974 – 2009. Mem. Soc. Astron. Ital. 81, 643 – 645.
Megier, A., Strobel, A., Galazutdinov, G.A., Krełowski, J.: 2009, The interstellar Ca ii distance scale. Astron. Astrophys. 507, 833 – 840. doi: 10.1051/0004-6361/20079144 .
Ortiz, A., Rast, M.: 2005, How good is the Ca ii K as a proxy for the magnetic flux? Mem. Soc. Astron. Ital. 76, 1018 – 1021.
Pierce, A.K., Breckinridge, J.B.: 1974, The Kitt Peak table of photographic solar spectrum wavelengths. KPNO contribution 559.
Rutten, R.G.M.: 1984, Magnetic structure in cool stars. VII – absolute surface flux in CA ii H and K line cores. Astron. Astrophys. 130, 353 – 360.
Toussaint, R.M., Harvey, J.W., Toussaint, D.: 2003, Improved convergence for CCD gain calibration using simultaneous-overrelaxation techniques. Astron. J. 126, 1112 – 1118. doi: 10.1086/376846 .
Vieytes, M.C., Mauas, P.J.D., Díaz, R.F.: 2009, Chromospheric changes in K stars with activity. Mon. Not. Roy. Astron. Soc. 398, 1495 – 1504. doi: 10.1111/j.1365-2966.2009.15207.x .
Vieytes, M., Mauas, P., Cacciari, C., Origlia, L., Pancino, E.: 2011, Modelling chromospheric line profiles as diagnostics of velocity fields in ω Centauri red giant stars. Astron. Astrophys. 526, A4. doi: 10.1051/0004-6361/201015455 .
Wallace, L., Hinkle, K., Livingston, W.: 2007, An atlas of the spectrum of the Solar photosphere from 13 500 to 33 980 cm −1 (2942 to 7405 Å).
White, O.R., Livingston, W.: 1978, Solar luminosity variation. II – Behavior of calcium H and K at solar minimum and the onset of cycle 21. Astrophys. J. 226, 679 – 686. doi: 10.1086/156650 .
Wilson, O.C.: 1968, Flux measurements at the centers of stellar H- and K-lines. Astrophys. J. 153, 221 – 234. doi: 10.1086/149652 .
Wilson, O.C., Vainu Bappu, M.K.: 1957, H and K emission in late-type stars: Dependence of line width on luminosity and related topics. Astrophys. J. 125, 661 – 683. doi: 10.1086/146339 .
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Bertello, L., Pevtsov, A.A., Harvey, J.W. et al. Improvements in the Determination of ISS Ca ii K Parameters. Sol Phys 272, 229 (2011). https://doi.org/10.1007/s11207-011-9820-8
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DOI: https://doi.org/10.1007/s11207-011-9820-8