Search Publications
Growing a nuclear star cluster from star formation and cluster mergers: The JWST NIRSpec view of NGC 4654
Arribas, Santiago; Bunker, Andrew J.; Lützgendorf, Nora +10 more
We present a detailed study of the centre of NGC 4654, a Milky Way-like spiral galaxy in the Virgo cluster that has been reported to host a double stellar nucleus, thus promising a rare view of ongoing star cluster infall into a galaxy nucleus. Analysing JWST NIRSpec integral-field spectroscopic data in combination with Hubble Space Telescope Wide…
A spectroscopic and kinematic survey of fast hot subdwarfs
Rauch, T.; Geier, S.; Gänsicke, B. T. +19 more
Hot subdwarfs (sdO/B) are the stripped helium cores of red giants formed via binary interactions. Close hot subdwarf binaries with massive white dwarf companions have been proposed as possible progenitors of thermonuclear supernovae type Ia (SN Ia). If the supernova is triggered by stable mass transfer from the helium star, the companion should su…
ExoplaNeT accRetion mOnitoring sPectroscopic surveY (ENTROPY): I. Evidence for magnetospheric accretion in the young isolated planetary-mass object 2MASS J11151597+1937266
Viswanath, Gayathri; Janson, Markus; Szulágyi, Judit +7 more
Context. Accretion among planetary mass companions is a poorly understood phenomenon, due to the lack of both observational and theoretical studies. The detection of emission lines from accreting gas giants facilitates detailed investigations into this process. Aims. This work presents a detailed analysis of Balmer lines from one of the few known …
Sublimation of volatiles from H2O:CO2 bulk ices in the context of comet 67P/Churyumov-Gerasimenko. I. N2 and CO
Wurz, P.; Altwegg, K.; Rubin, M. +6 more
Context. Comets are considered to be remnants from the formation of the Solar System. ESA's Rosetta mission targeted comet 67P/Churyumov-Gerasimenko and was able to record high-quality data on its chemical composition and outgassing behaviour, including low abundances of N2 that are observed to be correlated with H2O and CO
Unraveling the kinematics of IZw18: A detailed study of ionized gas with MEGARA/GTC
Kehrig, C.; Pérez-Montero, E.; Vílchez, J. M. +6 more
This study offers an in-depth analysis of the kinematic behavior of ionized gas in IZw18, a galaxy notable for its extremely low metallicity and close proximity, utilizing data from MEGARA/GTC. We explored the structure and dynamics of the galaxy through Hα line profiles, applying single and double Gaussian component fittings to create detailed ma…
Non-thermal electrons in an eruptive solar event: Magnetic structure, confinement, and escape into the heliosphere
Klein, Karl-Ludwig; Kollhoff, Alexander; Salas Matamoros, Carolina +1 more
Context. Filament eruptions and coronal mass ejections (CMEs) reveal large-scale instabilities of magnetic structures in the solar corona. Some of them are accompanied by radio emission, which at decimetric and longer wavelengths is a signature of electron acceleration that may be different from the acceleration in impulsive flares. The radio emis…
Comparison of magnetic data products from Solar Orbiter SO/PHI-FDT and SDO/HMI
Woch, J.; Solanki, S. K.; Schou, J. +34 more
Context. The Polarimetric and Helioseismic Imager (SO/PHI), on board the Solar Orbiter mission, is the first photospheric magnetograph and tachograph to observe the Sun from outside the Sun-Earth line. The Full Disc Telescope (FDT) of SO/PHI, images the whole solar disk with a spatial resolution that varies with the distance between the Sun and th…
Periodicity from X-ray sources within the inner Galactic disk
Hailey, Charles J.; Mori, Kaya; Morris, Mark R. +9 more
Aims: For many years it had been claimed that the Galactic ridge X-ray emission at the Galactic Center (GC) is truly diffuse in nature. However, with the advancement of modern X-ray satellites, it has been found that most of the diffuse emission actually comprises thousands of previously unresolved X-ray point sources. Furthermore, many studi…
Straight outta photosphere: Open solar flux without coronal modeling
Tähtinen, Ismo; Asikainen, Timo; Mursula, Kalevi
Context. The open solar flux, that is, the total magnetic flux escaping the Sun, is one of the most important parameters connecting solar activity to the Earth. The open solar flux is commonly estimated from photospheric magnetic field measurements by making model assumptions about the solar corona. However, the question in which way the open sola…
Once in a blue stream. Detection of recent star formation in the NGC 7241 stellar stream with MEGARA
Leaman, Ryan; Erkal, Denis; Voggel, Karina T. +23 more
Aims: In this work we study the striking case of a narrow blue stream with a possible globular cluster-like progenitor around the NGC 7241 galaxy and its foreground dwarf companion. We want to figure out if the stream was generated by tidal interaction with NGC 7241 or if it first interacted with the foreground dwarf companion and later both …