Orbits for Nine Binaries and One Linear Solution

Abstract

The subject of the present paper is the analysis of the orbital elements for nine binaries: WDS 00463–0634 = HDS 101, WDS 03264+3520 = HDS 430, WDS 03307–1926 = HDS 441, WDS 04025+0638 = HDS 510, WDS 09252+4606 = HDS 1353, WDS 09446+6459 = CHR 176, WDS 10294+1211 = HDS 1507, WDS 10596+1800 = HDS 1568, and WDS 14562+1745 = HDS 2108. The orbital elements are calculated for the first time for all of them. The eight binaries, denoted as HDS, were discovered during the Hipparcos mission. One binary, denoted as CHR, was discovered in the Center for High Angular Resolution Astronomy, CHARA, in 1988. These studied pairs have measured separations of less than 0.41 arcsec. For the eight pairs that have measured separations less than 0.3 arcsec, the resulting orbital periods fall within 16 and 55 years, and for the remaining one pair the orbital period is 94 years. In addition to the orbital elements, we also give (O − C) residuals in θ and ρ, masses, dynamical parallaxes, absolute magnitudes, spectral types, and ephemerides for the next five years. We also present one linear solution for the double star WDS 19218+7708 = HDS 2740 that has also been calculated for the first time. For this system we give (O − C) residuals in θ and ρ as well, along with ephemerides for the next five years.

First light of a holographic aperture mask: Observation at the Keck OSIRIS Imager

“…Moreover, the gradient as a function of wavelength is consistent with the combined F0 and F7 scenario. This means that our estimate of the brightness ratio also suggests a difference between the components' temperatures and spectral types, in line with Cvetković et al (2016).…”

“…16: Recovered brightness ratio of the binary as a function of wavelength. The green line shows the expected brightness ratio for the spectral types (F0 and F7) reported by Cvetković et al (2016). The orange line is the expected brightness ratio when both components are of type F2.…”

“…elements have been published in the literature (Cvetković et al 2016, Tokovinin 2017, allowing us to compute the predicted onsky separation vector at any point in time. In 2016, Cvetković et al published a result that was based on four measurements spread over more than a decade.…”

“…HD 90823 is an ideal verification target because (i) the binary has a relatively low contrast, ∆m ≈ 1.2, in the V and I bands, making the companion easy to detect and (ii) two sets of orbital elements have been published in the literature (Cvetković et al 2016, Tokovinin 2017, allowing us to compute the predicted onsky separation vector at any point in time. In 2016, Cvetković et al published a result that was based on four measurements spread over more than a decade.…”

“…According to the SIMBAD database, both stars are of type F2, but the corresponding quality labels suggest little reliability. On the other hand, Cvetković et al (2016) state that the bright component is hotter (type F0) than the faint one (type F7), with the difference in surface temperatures being roughly 1000 K. In order to find out which claim is most likely based on the HAM data, we computed the Planck spectra of the components in both scenarios, scaled them according to the reported contrast in theV band (see Table 2), and divided them in the Hbb filter. Figure 16 illustrates that the actual measurements lie in between the theoretical curves but fully within the 1σ envelope of the combined F0 and F7 scenario.…”