Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 1311.0797

Identification of new Galactic symbiotic stars with SALT. I. Initial discoveries and other emission line objects

Brent Miszalski·Joanna Mikołajewska
View original source ↗Read source document ↗Export metadata ↓

Abstract

We introduce the first results from an ongoing, systematic survey for new symbiotic stars selected from the AAO/UKST SuperCOSMOS H$α$ Survey (SHS). The survey aims to identify and characterise the fainter population of symbiotic stars underrepresented in extant catalogues. The accreting white dwarfs (WDs) in symbiotic stars, fuelled by their red giant donors with high mass loss rate winds, make them promising candidates for type Ia supernovae. Several candidates were observed spectroscopically with the Southern African Large Telescope (SALT). A total of 12 bona-fide and 3 possible symbiotic stars were identified. The most remarkable example is a rare carbon-rich symbiotic star that displays coronal [Fe X] $λ$6375 emission, suggesting it may be a supersoft X-ray source with a massive WD. Several other emission line objects with near-infrared colours similar to symbiotic stars are listed in an appendix, including 6 B[e] stars, 4 planetary nebulae (PNe), 2 possible Be stars, one [WC9] Wolf-Rayet (WR) central star of a PN and one WC9 WR star. These initial discoveries will help shape and refine the candidate selection criteria that we expect will uncover several more symbiotic stars as the survey progresses.

Explore related subjects

astro-ph.SR

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Brent Miszalski, Joanna Mikołajewska. 2014-02-10. Identification of new Galactic symbiotic stars with SALT. I. Initial discoveries and other emission line objects. https://doi.org/10.1093/mnras%2Fstu292

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Velocity-space turbulent cascade in the near-Sun solar wind: first insights from the Parker Solar Probe mission

In space plasmas, the rarity of collisions leads to complex structures in the velocity space where a turbulent cascade of the velocity distribution function fluctuations is thought to occur. Previous studies have explored this phenomenon using the Hermite decomposition of the ion velocity distribution function (VDF) in both magnetosheath data and numerical simulations. In this work, we investigate the Hermite spectrum of the ion VDFs measured by Parker Solar Probe in the inner heliosphere. We analyze a superalfvénic stream at a radial distances of $R \approx 28 R_{sun}$ and a subalfvénic at $R \approx 11 R_{sun}$, the former characterized by a prevalence of VDFs with suprathermal beams (also known as hammerhead). The Hermite analysis is also compared with various proxies of energization and dissipation, in order to establish a connection between turbulent cascades in real space and those in the velocity space. A qualitative agreement between the energization proxies and the Hermite analysis is observed. The results are suggestive of the presence of a dual cascade in real and velocity space.

astro-ph.SR↗
arXiv2026

simesh: A Python Framework for Quantitative Analysis of Native AMR Data from MPI-AMRVAC

Adaptive mesh refinement (AMR) is widely used in large-scale astrophysical simulations, but the resulting multilevel data are challenging to analyze quantitatively. We present simesh, an independent Python framework for quantitative analysis of cell-centered fields on block-structured AMR meshes. The current implementation targets three-dimensional Cartesian datasets from MPI-AMRVAC and compatible AGILE snapshots, preserving the native AMR hierarchy and connecting complementary scientific diagnostics within a common numerical representation. The framework combines Python workflow interfaces with compiled Cython kernels, supporting efficient analysis on AMR meshes. We compare native AMR analysis with a VTK point-data conversion and uniform-grid resampling, which shows that changes in data association, interpolation support, and differentiation scale affect both sampled magnetic fields and derived current densities. Small differences in the sampled primary field can become more pronounced in derivative-based quantities, particularly near coarse-fine interfaces. The applications combine field diagnostics, tracing, regional statistics, and line-of-sight integration on the same native AMR representation. simesh makes these operations available through reusable Python interfaces for reproducible analysis of multiscale simulation data.

astro-ph.SR↗
arXiv2026

Detection of Solar-like Oscillations and Granulation at Infrared Wavelengths using JWST

Stellar oscillations and granulation are key probes of stellar convection, one of the most poorly understood processes in stars. Stellar models predict strong wavelength dependence of the amplitudes of oscillations and granulation, but hitherto both processes have only been measured at optical wavelengths. Here we present the first detection of oscillations and granulation at infrared wavelengths, using JWST time-series observations of the F6V main-sequence star WASP-121 that were obtained to study the atmosphere of an exoplanet. We find that the amplitudes of oscillations and granulation decrease with wavelength, consistent with expectations, but with a functional form that deviates from simple blackbody scaling. The detection opens the door to detailed tests of 3D convection models, facilitates the combined modeling of stellar and exoplanet signals in JWST passbands for exoplanet observations, and supports the predicted asteroseismic yields from the infrared time-domain data that will soon be obtained by the Roman Space Telescope.

astro-ph.SR↗