Scanner observations of selected cool stars

Abstract

Photoelectric spectral scans at 30-1 resolution of 9 dwarfs, 10 giants and 6 supergiants with spectral types GO to M5 are presented. All stars were observed every 4 j from X3300 to 47000. Absorption features observed at this resolution coincide with.' strong atomic lines of Fe I,II, Ca I,II, MgI, and Na I; vibrational bands of the electronic transitions of TiO, MgH, CaH, SiH, AlH, CN, CH, C 2 , OH, and NH. The dependence of the 4 3 7 40 Fe I blend and the X3440 depression on temperature is discussed.

Temperature stratification of the atmosphere of Arcturus

“…The results of absolute calibration of Ayres and Johnson [4] and Ayres and Linsky [5] based on the photometric data of Fay et al [16] and Willstrop [77] were used to reduce the spectra of the H and K lines taken from the atlas Hinkle et al [34] to an absolute unit scale. Figure 4 shows the obtained profiles of radiation flux in the H and K lines in absolute units.…”

“…Figure 4 shows the obtained profiles of radiation flux in the H and K lines in absolute units. According to Ayres and Linsky [5], the Figure 4: Absolute flux in the H and K spectrum of Arcturus according to the absolute calibration of Ayres and Johnson [4] that is based on photometric data of Fay et al [16] (solid line, diamonds) and according to the absolute calibration of Ayres and Linsky [5] based on photometric data of Willstrop [77] (red dashed line and crosses). The rms deviation between the indicated calibrations in the chosen points of the profile amounts to 7.2%.…”

“…This is caused by the uncertainty of measurements of the angular diameter of Arcturus made back then and by the possible errors of photometry and determination of the gauge factors averaged over the photometric bands. Bands with a width of 5 and 3 nm were used by Fay et al [16] and Willstrop [77], respectively. Figure 4 shows that the maximum difference (5-10%) between the calibration results based on two different sets of photometric data is developed in the far wing of the H line.…”

“…Inclusion of unknown absorption in the continuum using the factor f (λ) made it possible to produce a satisfactory match between the synthetic spectrum (crosses) and observations with σ = 0.028. In the process, the values of f (λ) = 2.45, 1.95, 1.65, 1.45, and 1.35 (photometry of Fay et al [16]) and f (λ) = 2.20, 1.90, 1.70, 1.55, and 1.45 (photometry of Willstrop [77]) corresponding to λ = 390.0, 392.5, 395.0, 398.0, and 400.0 nm, respectively, were obtained. We attempted to produce a better match between the profiles (i.e., obtain a σ value that would be equal to the solar one) by varying the temperature trend, but failed.…”

An eclipsing post-common-envelope binary in the field of the Kepler mission

“… DOLORES on‐eclipse spectrum (top), the ISIS red spectrum (bottom) and the active M4V template (in grey). Some relevant spectral features are labelled (Fay, Stein & Warren 1974; Kirkpatrick, Henry & McCarthy 1991). …”