Search Publications
HD 117214 debris disk: scattered-light images and constraints on the presence of planets
Quanz, S. P.; Ginski, C.; Henning, Th. +34 more
Context. Young stars with debris disks are the most promising targets for an exoplanet search because debris indicate a successful formation of planetary bodies. Debris disks can be shaped by planets into ring structures that give valuable indications on the presence and location of planets in the disk.
Aims: We performed observations of the …
ZFIRE: Measuring Electron Density with [O II] as a Function of Environment at z = 1.62
Papovich, Casey; Kewley, Lisa J.; Harshan, Anishya +8 more
The global star formation rates (SFR) of galaxies at fixed stellar masses increase with redshift and are known to vary with environment up to z ∼ 2. We explore here whether the changes in the SFRs also apply to the electron densities of the interstellar medium by measuring the [O II] (λ 3726, λ 3729) ratio for cluster and field galaxies at z ∼ 2. …
Large non-radial propagation of a coronal mass ejection on 2011 January 24
Mierla, M.; D'Huys, E.; Stenborg, G. +6 more
Understanding the deflection of coronal mass ejections (CMEs) is of great interest to the space weather community because of their implications for improving the prediction of CME. This paper aims to shed light into the effects of the coronal magnetic field environment on CME trajectories. We analyze the influence of the magnetic environment on th…
High-energy characteristics of the accretion-powered millisecond pulsar IGR J17591-2342 during its 2018 outburst. XMM-Newton, NICER, NuSTAR, and INTEGRAL view of the 0.3-300 keV X-ray band
Tsygankov, S. S.; Kuiper, L.; Poutanen, J. +4 more
IGR J17591-2342 is an accreting millisecond X-ray pulsar, discovered with INTEGRAL, which went into outburst around July 21, 2018. To better understand the physics acting in these systems during the outburst episode, we performed detailed temporal-, timing-, and spectral analyses across the 0.3-300 keV band using data from NICER, XMM-Newton, NuSTA…
On the Coronal Temperature in Solar Microflares
Testa, Paola; Reale, Fabio
We present a study of solar imaging and spectral observations of a microflare, focusing on the temperature diagnostics provided by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory, and the Extreme-Ultraviolet Imaging Spectrometer (EIS) on board Hinode. Our data analysis, in particular from the emission in the 131 and …
MeerKAT HI commissioning observations of MHONGOOSE galaxy ESO 302-G014
Groot, P. J.; Dettmar, R. -J.; Walter, F. +43 more
Aims: We present the results of three commissioning H I observations obtained with the MeerKAT radio telescope. These observations make up part of the preparation for the forthcoming MHONGOOSE nearby galaxy survey, which is a MeerKAT large survey project that will study the accretion of gas in galaxies and the link between gas and star format…
67P/Churyumov-Gerasimenko's dust activity from pre- to post-perihelion as detected by Rosetta/GIADA
Fulle, M.; Güttler, C.; Tubiana, C. +18 more
We characterized the 67P/Churyumov-Gerasimenko's dust activity, by analysing individual dust particle velocity and momentum measurements of Grain Impact Analyser and Dust Accumulator (GIADA), the dust detector onboard the ESA/Rosetta spacecraft, collecting dust from tens to hundreds of kilometres from the nucleus. Specifically, we developed a proc…
On the Relation between the Hard X-Ray Photon Index and Accretion Rate for Super-Eddington Accreting Quasars
Luo, Bin; Huang, Jian; Du, Pu +3 more
We investigate whether the correlation between the hard X-ray photon index ( ${\rm{\Gamma }}$ ) and accretion rate for super-Eddington accreting quasars is different from that for sub-Eddington accreting quasars. We construct a sample of 113 bright quasars from the Sloan Digital Sky Survey Data Release 14 quasar catalog, with 38 quasars as the sup…
ROSINA ion zoo at Comet 67P
Altwegg, K.; Balsiger, H.; Fuselier, S. A. +9 more
Context. The Rosetta spacecraft escorted Comet 67P/Churyumov-Gerasimenko for 2 yr along its journey through the Solar System between 3.8 and 1.24 au. Thanks to the high resolution mass spectrometer on board Rosetta, the detailed ion composition within a coma has been accurately assessed in situ for the very first time.
Aims: Previous cometary…
A broad-band X-ray spectral study of the Seyfert 1 galaxy ESO 141-G055 with XMM-Newton and NuSTAR
Laha, Sibasish; Ghosh, Ritesh
We have extensively studied the broad--band X-ray spectra of the source ESO 141-G055 using all available XMM-Newton and NuSTAR observations. We detect a prominent soft excess below $2\rm \, \, {\rm keV}$ , a narrow Fe line, and a Compton hump ( $\gt 10\rm \, \, {\rm keV}$ ). The origin of the soft excess is still debated. We used two models to des…