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A fully-spectroscopic triple-source-plane lens: the Jackpot completed
Collett, Thomas E.; Smith, Russell J.
We present a spectroscopic determination of the redshift of the second source in the Jackpot gravitational lens system J0946 + 1006, for which only a photometric estimate of zphot = 2.41$^{+0.04}_{-0.21}$ has previously been available. By visually inspecting an archival Very Large Telescope (VLT) X-Shooter observation, we located a sing…
WIYN Open Cluster Study. LXXXV. Li in NGC 2243: Implications for Stellar and Galactic Evolution
Twarog, Bruce A.; Anthony-Twarog, Barbara J.; Deliyannis, Constantine P.
High-dispersion spectra in the Li λ6708 region have been obtained and analyzed in the old, metal-deficient cluster NGC 2243. From Hydra spectra for 29 astrometric and radial velocity members, we derive rotational velocities, as well as [Fe/H], [Ca/H], [Si/H], and [Ni/H] based on 17, 1, 1, and 3 lines, respectively. Using ROBOSPECT, an automatic eq…
Runaway blue main-sequence stars at high Galactic latitudes. Target selection with Gaia and spectroscopic identification
Raddi, Roberto; Irrgang, Andreas; Heber, Ulrich +2 more
Context. The ESA Gaia mission is a remarkable tool for stellar population analysis through its accurate Hertzsprung-Russell diagram. Its precise astrometry has propelled detailed kinematic studies of the Milky Way and the identification of high-velocity outliers.
Aims: Motivated by the historical identification of runaway main-sequence (MS) s…
A new transient ultraluminous X-ray source in NGC 7090
Salvaterra, R.; Harrison, F. A.; Stern, D. +17 more
We report on the discovery of a new, transient ultraluminous X-ray source (ULX) in the galaxy NGC 7090. This new ULX, which we refer to as NGC 7090 ULX3, was discovered via monitoring with Swift during 2019-2020, and to date has exhibited a peak luminosity of LX ~ 6 × 1039 erg s-1. Archival searches show that, prio…
On the Rigidity Spectrum of Cosmic-Ray Variations within Propagating Interplanetary Disturbances: Neutron Monitor and SOHO/EPHIN Observations at ∼1-10 GV
Vourlidas, Angelos; Heber, Bernd; Papaioannou, Athanasios +9 more
The rigidity dependence of all Forbush decreases (FDs) recorded from 1995 to 2015 has been determined using neutron monitor (NM) and Solar and Heliospheric Observatory (SOHO) (EPHIN) spacecraft data, covering the energy (rigidity) range from ∼433 MeV (1 GV) to 9.10 GeV (10 GV). We analyzed a total of 421 events and determined the spectrum in rigid…
ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions-VI. On the formation of the 'L' type filament in G286.21+0.17
Kim, Kee-Tae; Lee, Chang Won; Liu, Hong-Li +16 more
Filaments play an important role in star formation, but the formation process of filaments themselves is still unclear. The high-mass star-forming clump G286.21+0.17 (G286 for short) that contains an 'L' type filament was thought to undergo global collapse. Our high-resolution ALMA band 3 observations resolve the gas kinematics of G286 and reveal …
Fast flaring observed from XMMU J053108.3-690923 by eROSITA: a supergiant fast X-ray transient in the Large Magellanic Cloud
Haberl, F.; Ducci, L.; Vasilopoulos, G. +3 more
Context. Supergiant fast X-ray transients (SFXTs) are a peculiar class of supergiant high-mass X-ray binary (HMXB) systems characterised by extreme variability in the X-ray domain. In current models, this is mainly attributed to the clumpy nature of the stellar wind coupled with gating mechanisms involving the spin and magnetic field of the neutro…
The diffuse interstellar band around 8620 Å. I. Methods and application to the GIBS data set
Schultheis, M.; Recio-Blanco, A.; de Laverny, P. +6 more
Context. Diffuse interstellar bands (DIBs) are interstellar absorption features that widely exist in the optical and near-infrared wavelength range. DIBs play an important role in the lifecycle of the interstellar medium and can also be used to trace the Galactic structure.
Aims: We developed a set of procedures to automatically detect and me…
X-Ray Pulsar XTE J1858+034: Discovery of the Cyclotron Line and the Revised Optical Identification
Kretschmar, Peter; Doroshenko, Victor; Tsygankov, Sergey S. +7 more
We present the results of a detailed investigation of the poorly studied X-ray pulsar (XRP) XTE J1858+034 based on the data obtained with the NuSTAR observatory during the outburst of the source in 2019. The spectral analysis resulted in the discovery of a cyclotron absorption feature in the source spectrum at ∼48 keV in both the pulse phase-avera…
Colliding stellar wind modelling of the X-ray emission from WR 140
Zhekov, Svetozar A.
We modelled the Chandra and Rossi X-ray Timing Explorer X-ray spectra of the massive binary WR 140 in the framework of the standard colliding stellar wind (CSW) picture. Models with partial electron heating at the shock fronts are a better representation of the X-ray data than those with complete temperature equalization. Emission measure of the X…