Search Publications
High-energy particle enhancements in the solar wind upstream Mercury during the first BepiColombo flyby: SERENA/PICAM and MPO-MAG observations
Kallio, E.; Barabash, S.; Livi, S. +27 more
Context. The first BepiColombo Mercury flyby offered the unique opportunity to simultaneously characterize the plasma and the magnetic field properties of the solar wind in the vicinity of the innermost planet of the Solar System (0.4 AU).
Aims: In this study, we use plasma observations by SERENA/PICAM and magnetic field measurements by MPO-M…
Discovery of periodicities in two highly variable intermediate polars towards the Galactic centre
Mori, Kaya; Morris, Mark R.; Rea, Nanda +5 more
Aims: We performed a systematic analysis of X-ray point sources within 1.°5 of the Galactic centre using archival XMM-Newton data. While doing so, we discovered Fe Kα complex emission and pulsation in two highly variable sources, 4XMM J174917.7-283329 and 4XMM J174954.6-294336. In this work we report the findings of the …
Coordinated X-ray and UV absorption within the accretion disk wind of the active galactic nucleus PG 1126-041
Cappi, M.; Ponti, G.; Vignali, C. +14 more
Context. Accretion disk winds launched close to supermassive black holes (SMBHs) are a viable mechanism providing feedback between the SMBH and the host galaxy.
Aims: We aim to characterize the X-ray properties of the inner accretion disk wind of the nearby active galactic nucleus PG 1126-041 and to study its connection with the UV-absorbing …
A possible dwarf galaxy satellite-of-satellite problem in ΛCDM
Müller, Oliver; Heesters, Nick; Jerjen, Helmut +2 more
Dark matter clusters on all scales, and it is therefore expected that even substructure should host its own substructure. Using the Extragalactic Distance Database, we searched for dwarf-galaxy satellites of dwarf galaxies, that is, satellite-of-satellite galaxies, corresponding to these substructures of substructure. From investigation of Hubble …
PM 1-322: New variable planetary nebula
Paunzen, E.; Bernhard, K.; Hümmerich, S. +4 more
Context. Spectra of planetary nebulae (PNe) are characterised by strong forbidden emission lines and often also by an infrared (IR) excess. A few PNe show dust obscuration events and/or harbour long-period binaries. Some post-asymptotic giant branch stars, symbiotic stars, or B[e] stars may feature similar characteristics. Recently, dust clouds ec…
The Effelsberg survey of FU Orionis and EX Lupi objects. I. Host environments of FUors and EXors traced by NH3
Menten, K. M.; Ábrahám, P.; Kóspál, Á. +6 more
Context. FU Orionis (FUor) and EX Lupi (EXor) type objects represent two small but rather spectacular groups of low-mass, young, eruptive stars. In both cases, outbursts of several magnitudes are observed, which are attributed to enhanced mass accretion from the circumstellar disc onto the central protostar. Although these objects are well studied…
On the role of interplanetary shocks in accelerating MeV electrons
Vainio, R.; Dresing, N.; Morosan, D. E. +2 more
Context. One of the sources of solar energetic particle (SEP) events is shocks that are driven by fast coronal mass ejections (CMEs). They can accelerate SEPs up to relativistic energies and are attributed to the largest SEP events. New studies suggest that CME-driven shocks can potentially accelerate electrons to MeV energies in the vicinity of t…
Tracking the spectral properties of ESO 511-G030 across different epochs
Bianchi, S.; Cappi, M.; Done, C. +14 more
The Type 1 active galactic nucleus (AGN) ESO 511-G030, a formerly bright and soft excess dominated source, was observed in 2019 in the context of a multi-wavelength monitoring campaign. In the new exposures, the source was found to be in a flux state approximately ten times lower than archival exposures and without any trace of the soft excess. In…
AGN feedback in an infant galaxy cluster: LOFAR-Chandra view of the giant FRII radio galaxy J103025+052430 at z = 1.7
Prandoni, I.; Vignali, C.; Gilli, R. +19 more
In the nearby universe, jets from active galactic nuclei (AGN) are observed to have a dramatic impact on their surrounding extragalactic environment. The effect of jets at high redshift (z > 1.5) is instead much more poorly constrained. However, studying the jet impact at cosmic noon, the epoch in which both star formation and AGN activity peak…
Studying X-ray instruments with galaxy clusters
Molendi, S.; Nevalainen, J.
Aims: Our aim is to apply a scientific approach to the problem of the effective area cross-calibration of the XMM-Newton EPIC instruments. Using a sample of galaxy clusters observed with XMM-Newton EPIC, we aim to quantify the effective area cross-calibration bias between the EPIC instruments as implemented in the public calibration database …