Results 1 to 10 of about 72 (61)
New Method to Detect and Characterize Active Be Star Candidates in Open Clusters
Galaxies, 2023 With the aim of better understanding the physical conditions under which Be stars form and evolve, it is imperative to further investigate whether poorly studied young open clusters host Be stars.
Anahí Granada +3 more
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Reddening-Free Q Parameters to Classify B-Type Stars with Emission Lines
Galaxies, 2023 The emission-line B-type stars constitute a heterogeneous group. Many of these stars show similar optical spectroscopic features and color indices, making it difficult to classify them adequately by means of photometric and spectroscopic techniques. Thus,
Yael Aidelman, Lydia Sonia Cidale
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The Prevalence and Influence of Circumstellar Material around Hydrogen-rich Supernova Progenitors
The Astrophysical Journal, 2023 Narrow transient emission lines (flash-ionization features) in early supernova (SN) spectra trace the presence of circumstellar material (CSM) around the massive progenitor stars of core-collapse SNe.
Rachel J. Bruch +47 more
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Infrared Spectroscopy of Be Stars: Influence of the Envelope Parameters on Brackett-Series Behaviour
Galaxies, 2023 The IR spectra of Be stars display numerous hydrogen recombination lines, constituting a great resource for obtaining information on the physical and dynamic structures of different regions within the circumstellar envelope.
Yanina Roxana Cochetti +4 more
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A Primordial Origin for the Gas-rich Debris Disks around Intermediate-mass Stars
The Astrophysical Journal Letters, 2023 While most debris disks consist of dust with little or no gas, a fraction have significant amounts of gas detected via emission lines of CO, ionized carbon, and/or atomic oxygen.
Riouhei Nakatani +6 more
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Open Astronomy, 2017 Ongoing studies of different groups of stars result in improving our knowledge of their fundamental parameters and evolutionary status. Also, they result in finding new phases of stellar evolution, which require theoretical explanation. At the same time,
Miroshnichenko Anatoly S. +9 more
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The Astrophysical Journal, 2023 We report ultra-wideband (0.4–4.0 GHz) observation of coherent radio emission via electron cyclotron maser emission (ECME) produced by the hot magnetic star HD 142990.
Barnali Das, Poonam Chandra
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Gamma-ray emission from early-type stars interacting with AGN jets
EPJ Web of Conferences, 2013 We study the interaction of early-type stars with the jets of active galactic nuclei. A bow-shock will form as a consequence of the interaction of the jet with the winds of stars and particles can be accelerated up to relativistic energies in these ...
Araudo Anabella T. +2 more
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Frontiers in Astronomy and Space Sciences, 2021 In the search for life on other planets, the presence of photosynthetic surface vegetation may be detectable from the colors of light it reflects. On the modern Earth, this spectral reflectance is characterized by a steep increase in reflectance between ...
Owen R. Lehmer +5 more
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SPECTROSCOPIC MONITORING OF THE B[E] OBJECTS FSCMA AND MOCAM
Odessa Astronomical Publications, 2019 Objects with the B[e] phenomenon exhibit permitted and forbidden emission lines due to the presence of circumstellar ionized gas and large infrared excesses due to processing of the stellar radiation by circumstellar dust.
A. K. Kuratova +10 more
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