Search Publications
A new X-ray look into four old pulsars
Mereghetti, Sandro; Rigoselli, Michela
We report on the X-ray properties of four rotation-powered pulsars with characteristic ages in the range 0.3-5 Myr, derived from the analysis of XMM-Newton archival observations. We found convincing evidence of thermal emission only in the phase-averaged spectrum of PSR B0114+58, which is well fitted by a blackbody with temperature kT = 0.17 ± 0.0…
Near-infrared spectroscopic observations of massive young stellar object candidates in the central molecular zone
Schultheis, M.; Ryde, N.; Rojas-Arriagada, A. +6 more
Context. The central molecular zone (CMZ) is a 200 pc region around the Galactic centre. The study of star formation in the central part of the Milky Way is of great interest as it provides a template for the closest galactic nuclei.
Aims: We present a spectroscopic follow-up of photometrically selected young stellar object (YSO) candidates i…
The bipolar jet of the symbiotic star R Aquarii: A study of its morphology using the high-resolution HST WFC3/UVIS camera
Eislöffel, Jochen; Melnikov, Stanislav; Stute, Matthias
Context. R Aqr is a symbiotic binary system consisting of a Mira variable with a pulsation period of 387 days and a hot companion which is presumably a white dwarf with an accretion disk. This binary system is the source of a prominent bipolar gaseous outflow.
Aims: We use high spatial resolution and sensitive images from the Hubble Space Tel…
Modelling the disc atmosphere of the low mass X-ray binary EXO 0748-676
Díaz Trigo, M.; Costantini, E.; Mehdipour, M. +1 more
Low mass X-ray binaries exhibit ionized emission from an extended disc atmosphere that surrounds the accretion disc. However, the atmosphere's nature and geometry is still unclear. In this work we present a spectral analysis of the extended atmosphere of EXO 0748-676 using high-resolution spectra from archival XMM-Newton observations. We model the…
Gaia Data Release 2
Tolstoy, Eline; Kotak, Rubina; Forveille, Thierry +1 more
Simultaneous broadband observations and high-resolution X-ray spectroscopy of the transitional millisecond pulsar PSR J1023+0038
D'Avanzo, P.; Campana, S.; Rea, N. +4 more
We report on the first simultaneous XMM-Newton, NuSTAR, and Swift observations of the transitional millisecond pulsar PSR J1023+0038 in the X-ray active state. Our multi-wavelength campaign allowed us to investigate with unprecedented detail possible spectral variability over a broad energy range in the X-rays, as well as correlations and lags amo…
Jovian electrons in the inner heliosphere. Proposing a new source spectrum based on 30 years of measurements
Potgieter, M. S.; Heber, B.; Vogt, A. +2 more
Context. Since the Pioneer 10 flyby of Jupiter it has become well known that electrons of Jovian origin dominate the lower MeV range of charged energetic particles in the inner heliosphere.
Aims: Because the Jovian source can be treated as point-like in numerical models, many attempts to investigate charged particle transport in the inner hel…
SHOTGLAS. I. The ultimate spectroscopic census of extreme horizontal branch stars in ω Centauri
Calamida, Annalisa; Latour, Marilyn; Randall, Suzanna K. +2 more
The presence of extreme horizontal branch (EHB) and blue hook stars in some Galactic globular clusters (GGCs) constitutes one of the remaining mysteries of stellar evolution. While several evolutionary scenarios have been proposed to explain the characteristics of this peculiar population of evolved stars, their observational verification has been…
Effects of resonant scattering of the Si IV doublet near 140 nm in a solar active region
Vial, J. -C.; Gontikakis, C.
Aims: In a previous study we analysed the C IV 1548.189 Å and 1550.775 Å lines observed with the Solar Ultraviolet Measurements of Emitted Radiation (SUMER), showing cases where the 1548.189 Å spectral profile was noticeably different from the 1550.775 Å one, profiles that we dubbed differentially shaped profiles. We explained this differenti…
Properties and redshift evolution of star-forming galaxies with high [O III]/[O II] ratios with MUSE at 0.28 < z < 0.85
Inami, H.; Richard, J.; Verhamme, A. +21 more
We present a study of the [O III]/[O II] ratios of star-forming galaxies drawn from Multi-Unit Spectroscopic Explorer (MUSE) data spanning a redshift range 0.28 < z < 0.85. Recently discovered Lyman continuum (LyC) emitters have extremely high oxygen line ratios: [O III]λ5007/[O II]λλ3726, 3729 > 4. Here we aim to understand the propertie…