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Synoptic maps from two viewpoints. Preparing for maps from SDO/HMI and SO/PHI data
Solanki, S. K.; Schou, J.; Valori, G. +2 more
Context. Over recent decades, various kinds of magnetic synoptic chart products have seen major improvements in observation cadence, resolution, and processing, but their creation is still limited by the 27.27 day rotation rate of the solar surface.
Aims: Co-observation from a second vantage point away from the Earth-Sun line with SO/PHI enab…
On the nature of the eccentric eclipsing binary star SY Phe with a pulsating γ Dor component
Erdem, Ahmet; Sürgit, Derya; Engelbrecht, Chris A. +3 more
Spectroscopic observations of the eccentric binary system SY Phe were made at the South African Astronomical Observatory in 2019, 2020, and 2021, and its mid-resolution spectra were obtained. The radial velocities of the component stars were measured using the cross-correlation method and Fourier disentangling of the spectra. The spectral type (he…
A machine learning approach to estimate mid-infrared fluxes from WISE data
Fonseca-Bonilla, Nuria; Cerdán, Luis; Noriega-Crespo, Alberto +1 more
Context. While the Wide-field Infrared Survey Explorer (WISE) is the largest, best quality infrared all-sky survey to date, a smaller coverage mission, Spitzer, was designed to have better sensitivity and spatial resolution at similar wavelengths. Confusion and contamination in WISE data result in discrepancies between them. Aims. We aim to presen…
NGC 7314: X-Ray Study of the Evolving Accretion Properties
Chang, Hsiang-Kuang; Chatterjee, Debjit; Jana, Arghajit +1 more
We present a comprehensive analysis of the timing and spectral properties of NGC 7314, a Seyfert 1.9 galaxy, using X-ray observations from XMM-Newton, NuSTAR, and RXTE/proportional counter array (PCA). The timing analysis reveals significant variability across different energy bands, with fractional variability values consistent with previous stud…
Luminosity Class of the Symbiotic Stars 4U1954+319 and ZZ CMi
Zamanov, R.; Stoyanov, K. A.; Takey, A. +9 more
We performed optical photometry and spectral observations of the symbiotic stars 4U1954+319 and ZZ CMi. For 4U1954+319, using high-resolution spectra, we, measure the equivalent widths of diffuse interstellar bands (DIBs) and estimate the interstellar reddening E(B−V)=0.83 ± 0.09. Using the GAIA distances and our photometry, we find: (1) the absol…
HD 214220 (BD+56 2813): An eclipsing binary with its primary component at the end of the main sequence
Schmutz, W.
Context. Analysis of the light curves of an eclipsing binary allows one to derive the absolute dimensions of the system. This in turn yields information on the radii of the components, which allows the stars to be accurately placed on the Hertzsprung-Russell diagram and their evolutionary phase to be interpreted via comparisons to tracks of stella…
The Stellar Content of the Young Open Cluster Berkeley 50 (IC 1310)
Massey, Philip; Speckert, Meghan; Skiff, Brian A.
We observed the Galactic open cluster Berkeley 50 in order to determine its stellar content, distance, and age. We obtained UBV photometry of 1145 stars in a 12.'3 × 12.'3 field, and used Gaia proper motions and parallaxes to identify 64 members, of which we obtained spectra of the 17 brightest members. The majority of the observed population we c…
Hard X-rays from the deep solar atmosphere. An unusual UV burst with flare properties
Peter, H.; Chitta, L. P.; Young, P. R. +4 more
Explosive transient events occur throughout the solar atmosphere. The differing manifestations range from coronal mass ejections to Ellermann bombs. The former may have negligible signatures in the lower atmosphere, and the latter may have negligible nonthermal emissions such as hard X-radiation. A solar flare generally involves a broad range of e…
The 24 Aqr triple system: A closer look at its unique high-eccentricity hierarchical architecture
Horch, Elliott P.; Abushattal, Ahmad A.; Al-Wardat, Mashhoor A. +4 more
As its periastron passage occurred during the third quarter of 2020, system 24 Aqr is of particular significance. New visual solutions for the latest speckle interferometry observations collected by the Lowell Discovery Telescope (LTD) with its new QWSSI speckle camera are presented here. A variety of techniques were used to analyze the system, in…
Filling in the blanks: A method to infer the substructure membership and dynamics of 5D stars
Helmi, Amina; Callingham, Thomas M.
Context. In the solar neighbourhood, only ∼2% of stars in the Gaia survey have a line-of-sight velocity (vlos) contained within the RVS catalogue. These limitations restrict conventional dynamical analysis, such as finding and studying substructures in the stellar halo. Aims. We aim to present and test a method to infer a probability de…