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New hard X-ray sources discovered in the ongoing INTEGRAL Galactic plane survey after 14 yr of observations
Sunyaev, Rashid A.; Tsygankov, Sergey S.; Lutovinov, Alexander A. +3 more
The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) continues to successfully work in orbit after its launch in 2002. The mission provides the deepest ever survey of hard X-ray sources throughout the Galaxy at energies above 20 keV. We report on a catalogue of new hard X-ray source candidates based on the latest sky maps comprising 14 y…
Vertical structure of the near-surface expanding ionosphere of comet 67P probed by Rosetta
Altwegg, K.; Behar, E.; Nilsson, H. +14 more
The plasma environment has been measured for the first time near the surface of a comet. This unique data set has been acquired at 67P/Churyumov-Gerasimenko during ESA/Rosetta spacecraft's final descent on 2016 September 30. The heliocentric distance was 3.8 au and the comet was weakly outgassing. Electron density was continuously measured with Ro…
Are star formation rates of galaxies bimodal?
Feldmann, Robert
Star formation rate (SFR) distributions of galaxies are often assumed to be bimodal with modes corresponding to star-forming and quiescent galaxies, respectively. Both classes of galaxies are typically studied separately, and SFR distributions of star-forming galaxies are commonly modelled as lognormals. Using both observational data and results f…
G10/COSMOS: 38 band (far-UV to far-IR) panchromatic photometry using LAMBDAR
Robotham, Aaron S. G.; Davies, L. J. M.; Driver, S. P. +3 more
We present a consistent total flux catalogue for a ∼1 deg2 subset of the Cosmic Evolution Survey (COSMOS) region (RA ∈ [149.55°, 150.65°], Dec. ∈ [1.80°, 2.73°]) with near-complete coverage in 38 bands from the far-ultraviolet to the far-infrared. We produce aperture matched photometry for 128 304 objects with I < 24.5 in a manner th…
Measurements of the electrostatic potential of Rosetta at comet 67P
Nilsson, H.; Eriksson, A. I.; Johansson, F. L. +3 more
We present and compare measurements of the spacecraft potential (Vs/c) of the Rosetta spacecraft throughout its stay in the inner coma of comet 67P/Churyumov-Gerasimenko, by the Rosetta Plasma Consortium-LAngmuir Probe (RPC-LAP) and Ion Composition Analyzer (RPC-ICA) instruments. Vs/c has mainly been negative, driven by the h…
On the timing properties of SAX J1808.4-3658 during its 2015 outburst
Sanna, A.; Tailo, M.; Papitto, A. +7 more
We present a timing analysis of the 2015 outburst of the accreting millisecond X-ray pulsar SAX J1808.4-3658, using non-simultaneous XMM-Newton and NuSTAR observations. We estimate the pulsar spin frequency and update the system orbital solution. Combining the average spin frequency from the previous observed, we confirm the long-term spin-down at…
Simultaneous X-ray and radio observations of the radio-mode-switching pulsar PSR B1822-09
Kuiper, L.; Hermsen, W.; Hessels, J. W. T. +7 more
We report on simultaneous X-ray and radio observations of the radio-mode-switching pulsar PSR B1822-09 with ESA's XMM-Newton and the Westerbork Synthesis Radio Telescope, Giant Metrewave Radio Telescope and Lovell radio telescopes. PSR B1822-09 switches between a radio-bright and radio-quiet mode, and we discovered a relationship between the durat…
Flares, wind and nebulae: the 2015 December mini-outburst of V404 Cygni
Ponti, G.; Dhillon, V. S.; Charles, P. A. +22 more
After more than 26 years in quiescence, the black hole transient V404 Cyg went into a luminous outburst in 2015 June, and additional activity was detected in late December of the same year. Here, we present an optical spectroscopic follow-up of the December mini-outburst, together with X-ray, optical and radio monitoring that spanned more than a m…
H0LiCOW VII: cosmic evolution of the correlation between black hole mass and host galaxy luminosity
Treu, Tommaso; Auger, Matthew W.; Morishita, Takahiro +8 more
Strongly lensed active galactic nuclei (AGN) provide a unique opportunity to make progress in the study of the evolution of the correlation between the mass of supermassive black holes (M_BH) and their host galaxy luminosity (Lhost). We demonstrate the power of lensing by analysing two systems for which state-of-the-art lens modelling t…
Gravitationally lensed quasars in Gaia: I. Resolving small-separation lenses
McMahon, Richard G.; Auger, Matthew W.; Koposov, Sergey E. +1 more
Gaia's exceptional resolution (FWHM ∼ 0.1 arcsec) allows identification and cataloguing of the multiple images of gravitationally lensed quasars. We investigate a sample of 49 known lensed quasars in the Sloan Digital Sky Survey (SDSS) footprint, with image separations less than 2 arcsec, and find that eight are detected with multiple components i…