Search Publications
First detection of AlF line emission towards M-type AGB stars
Fonfría, J. P.; Velilla-Prieto, L.; Wedemeyer, S. +3 more
The nucleosynthesis production of fluorine (F) is still a matter of debate. Asymptotic giant branch (AGB) stars are one of the main candidates for F production. However, their contribution to the total F budget is not fully known due to the lack of observations. In this paper, we report the detection of aluminium monofluoride (AlF) line emission, …
A deep 1.4 GHz survey of the J1030 equatorial field: A new window on radio source populations across cosmic time
Prandoni, I.; Massardi, M.; Vignali, C. +12 more
We present deep L-Band observations of the equatorial field centered on the z = 6.3 Sloan Digital Sky Survey (SDSS) quasar (QSO). This field is rich of multiwavelength photometry and spectroscopy data, making it an ideal laboratory for galaxy evolution studies. Our observations reach a 1σ sensitivity of ~2.5 µJy at the center of the field. We extr…
Ultracool dwarfs identified using spectra in LAMOST DR7
Luo, A. -Li; Li, Yin-Bi; Zhang, Shuo +7 more
In this work, we identify 734 ultracool dwarfs with a spectral type of M6 or later, including one L0. Of this sample, 625 were studied spectroscopically for the first time. All of these ultracool dwarfs are within 360 pc, with a Gaia G magnitude brighter than ∼19.2 mag. By studying the spectra and checking their stellar parameters (Teff…
Multiwavelength observations of Swift J0243.6+6124 from 2017 to 2022
Liu, Wei; Wang, Xiaofeng; Sai, Hanna +8 more
Context.Swift J0243.6+6124 is a high-mass X-ray binary that went into a giant X-ray outburst in 2017. During this event, the X-ray luminosity reached the highest value ever measured in a galactic Be/X-ray binary.
Aims: Our aim is to study the long-term variability of Swift J0243.6+6124 after the 2017 major X-ray outburst.
Methods: We hav…
The ionised and molecular mass of post-common-envelope planetary nebulae. The missing mass problem
Alcolea, J.; Santander-García, M.; Bujarrabal, V. +2 more
Context. Most planetary nebulae (PNe) show beautiful, axisymmetric morphologies despite their progenitor stars being essentially spherical. Close binarity is widely invoked to help eject an axisymmetric nebula, after a brief phase of engulfment of the secondary within the envelope of the asymptotic giant branch (AGB) star, known as the common enve…
Thermal emission from bow shocks. II. 3D magnetohydrodynamic models of ζ Ophiuchi
Kavanagh, Patrick; Green, Samuel; Mackey, Jonathan +3 more
The nearby, massive, runaway star ζ Ophiuchi has a large bow shock detected in optical and infrared light and, uniquely among runaway O stars, diffuse X-ray emission detected from the shocked stellar wind. Here we make the first detailed computational investigation of the bow shock of ζ Ophiuchi, to test whether a simple model of the bow shock can…
Non-local thermodynamic equilibrium spectral analysis of five hot, hydrogen-deficient pre-white dwarfs
Raddi, Roberto; Munari, Ulisse; Werner, Klaus +3 more
Hot, compact, hydrogen-deficient pre-white dwarfs (pre-WDs) with effective temperatures of Teff > 70 000 K and a surface gravity of 5.0 < logg < 7.0 are rather rare objects despite recent and ongoing surveys. It is believed that they are the outcome of either single star evolution (late helium-shell flash or late helium-core fl…
XMM-Newton and Swift observations of supergiant high mass X-ray binaries
Romano, P.; Ferrigno, C.; Bozzo, E.
Wind-fed supergiant X-ray binaries are precious laboratories not only to study accretion under extreme gravity and magnetic field conditions, but also to probe the still highly debated properties of massive star winds. These include clumps, originating from the inherent instability of line driven winds, and larger structures. In this paper we repo…
Ca II triplet spectroscopy of Small Magellanic Cloud red giants. VI. Analysis of chemical properties of the main body
Geisler, D.; Mauro, F.; Angelo, M. S. +5 more
Aims: In this paper we analyze the chemical evolution of the main body of the SMC, adding six additional clusters to previously published samples, based on homogeneously determined and accurate metallicities.
Methods: We derived radial velocities and Ca II Triplet (CaT) metallicity of more than 150 red giants stars in six SMC star cluste…
Properties and applications of a predicted population of runaway He-sdO/B stars ejected from single degenerate He-donor SNe
Geier, S.; Justham, S.; Neunteufel, P. +4 more
Context. Thermonuclear supernovae (SNe), a subset of which are the highly important SNe of Type Ia and Iax, are relatively poorly understood phenomena. One of the more promising scenarios leading up to the creation of a thermonuclear SN involves accretion of helium-rich material from a binary companion. Following the SN, the binary companion is th…