Search Publications
BAT99 126: A multiple Wolf-Rayet system in the Large Magellanic Cloud with a massive near-contact binary
Shenar, T.; Sana, H.; Mahy, L. +3 more
Context. BAT99 126 is a multiple system in the Large Magellanic Cloud containing a Wolf-Rayet (WR) star, which has a reported spectroscopic (orbital) period of 25.5 days and a photometric (orbital) period of 1.55 days, and hence is potentially one of the shortest WR binaries known to date. Such short-period binary systems that contain a WR star in…
Comparison of active region upflow and core properties using simultaneous spectroscopic observations from IRIS and Hinode
Barczynski, Krzysztof; Brooks, David H.; Kleint, Lucia +2 more
Context. The origin of the slow solar wind is still an open issue. It has been suggested that upflows at the edge of active regions are a possible source of the plasma outflow and therefore contribute to the slow solar wind.
Aims: We investigate the origin and morphology of the upflow regions and compare the upflow region and the active regio…
The eROSITA Final Equatorial-Depth Survey (eFEDS). An X-ray-bright, extremely luminous infrared galaxy at z = 1.87
Nandra, Kirpal; Ueda, Yoshihiro; Terashima, Yuichi +15 more
In this study, we investigate the X-ray properties of WISE J090924.01+000211.1 (WISEJ0909+0002), an extremely luminous infrared (IR) galaxy (ELIRG) at zspec = 1.871 in the eROSITA Final Equatorial-Depth Survey. WISEJ0909+0002 is a WISE 22 µm source, located in the GAMA-09 field, which was detected by eROSITA during the performance…
The first GeV flare of the radio-loud narrow-line Seyfert 1 galaxy PKS 2004-447
Buson, S.; Wilms, J.; Kadler, M. +8 more
Context. On 2019 October 25, the Fermi-Large Area Telescope observed the first ever γ-ray flare from the radio-loud narrow-line Seyfert 1 galaxy PKS 2004−447 (z = 0.24). Prior to this discovery, only four sources of this type had shown a flare at gigaelectronvolt energies.
Aims: We report on follow-up observations in the radio, optical-UV, an…
Evaluation of a potential field source surface model with elliptical source surfaces via ballistic back mapping of in situ spacecraft data
Wimmer-Schweingruber, R. F.; Kruse, M.; Heidrich-Meisner, V.
Context. The potential field source surface (PFSS) model is an important tool that helps link the solar coronal magnetic field to the solar wind. Due to its simplicity, it allows for predictions to be computed rapidly and requires little input data, though at the cost of reduced accuracy compared to more complex models. So far, PFSS models have al…
A shock near the virial radius of the Perseus Cluster
Simionescu, A.; Kaastra, J. S.; Zhang, X. +6 more
Context. Previous X-ray studies of the Perseus Cluster, consisting of 85 Suzaku pointings along eight azimuthal directions, revealed a particularly steep decrease in the projected temperature profile near the virial radius (∼r200) towards the northwest (NW).
Aims: To further explore this shock candidate, another 4 Suzaku observatio…
The first heavy-metal hot subdwarf composite binary SB 744
Bastian, A.; Németh, P.; Vos, J. +1 more
Aims: The long-period sdOB+G1V type spectroscopic binary SB 744 reveals strong lines of fluorine and lead in the optical spectrum of the sdOB star and subsolar metallicity in the G1V companion thanks to a radial velocity follow-up study. Using high-quality observations and Gaia astrometric data, we aim to measure the chemical composition and …
Stellar population astrophysics (SPA) with the TNG. The Arcturus Lab
Dalessandro, E.; Sanna, N.; Mucciarelli, A. +4 more
Context. High-resolution spectroscopy in the near-infrared (NIR) is a powerful tool for characterising the physical and chemical properties of cool-star atmospheres. The current generation of NIR echelle spectrographs enables the sampling of many spectral features over the full 0.9-2.4 µm range for a detailed chemical tagging.
Aims: Wit…
Ammonia-methane ratios from H-band near-infrared spectra of late-T and Y dwarfs
Martín, E. L.; Burgasser, A. J.; Masseron, T. +4 more
Aims: Our goals are to investigate the relative absorption strengths of ammonia and methane using low-resolution H-band (1.5−1.7 microns) spectra obtained in the laboratory and compared with observational spectra of late-T and Y dwarfs, and to estimate what can be expected from the wide-angle low-resolution near-infrared spectroscopic survey …
The VLT-MUSE and ALMA view of the MACS 1931.8-2635 brightest cluster galaxy
Ziegler, B. L.; Postman, M.; Donahue, M. +4 more
We reveal the importance of ongoing in situ star formation in the brightest cluster galaxy (BCG) in the massive cool-core CLASH cluster MACS 1931.8-2635 at a redshift of z = 0.35 by analysing archival VLT-MUSE optical integral field spectroscopy. Using a multi-wavelength approach, we assessed the stellar and warm ionised medium components, which w…