Search Publications
Disk galaxy scaling relations at intermediate redshifts. I. The Tully-Fisher and velocity-size relations
Böhm, Asmus; Ziegler, Bodo L.
Aims: Galaxy scaling relations such as the Tully-Fisher relation (between the maximum rotation velocity Vmax and luminosity) and the velocity-size relation (between Vmax and the disk scale length) are powerful tools to quantify the evolution of disk galaxies with cosmic time.
Methods: We took spatially resolved slit…
Suzaku observations of the 2013 outburst of KS 1947+300
Hemphill, Paul B.; Rothschild, Richard E.; Fürst, Felix +9 more
We report on the timing and spectral analysis of two Suzaku observations with different flux levels of the high-mass X-ray binary KS 1947+300 during its 2013 outburst. In agreement with simultaneous NuSTAR observations, the continuum is well described by an absorbed power law with a cutoff and an additional blackbody component. In addition, we fin…
Dayside temperatures in the Venus upper atmosphere from Venus Express/VIRTIS nadir measurements at 4.3 µm
López-Valverde, M. A.; Gilli, G.; Peralta, J. +1 more
In this work, we analysed nadir observations of atmospheric infrared emissions carried out by VIRTIS, a high-resolution spectrometer on board the European spacecraft Venus Express. We focused on the ro-vibrational band of CO2 at 4.3 µm on the dayside, whose fluorescence originates in the Venus upper mesosphere and above. This is t…
Near-infrared photometry of WISE J085510.74-071442.5
Minniti, D.; Bayo, A.; Béjar, V. J. S. +7 more
Aims: We aim at obtaining near-infrared photometry and deriving the mass, age, temperature, and surface gravity of WISE J085510.74-071442.5 (J0855-0714), which is the coolest object beyond the solar system currently known.
Methods: We used publicly available data from the archives of the Hubble Space Telescope (HST) and the Very Large Te…
Multiwavelength study of the fast rotating supergiant high-mass X-ray binary IGR J16465-4507
Goldoni, P.; Chaty, S.; Simón-Díaz, S. +6 more
Context. Since its launch, the X-ray and γ-ray observatory INTEGRAL satellite has revealed a new class of high-mass X-ray binaries (HMXB) displaying fast flares and hosting supergiant companion stars. Optical and infrared (OIR) observations in a multi-wavelength context are essential to understand the nature and evolution of these newly discovered…
Joint signal extraction from galaxy clusters in X-ray and SZ surveys: A matched-filter approach
Arnaud, M.; Pratt, G. W.; Melin, J. -B. +1 more
The hot ionized gas of the intra-cluster medium emits thermal radiation in the X-ray band and also distorts the cosmic microwave radiation through the Sunyaev-Zel'dovich (SZ) effect. Combining these two complementary sources of information through innovative techniques can therefore potentially improve the cluster detection rate when compared to u…
Chromospheric evaporation flows and density changes deduced from Hinode/EIS during an M1.6 flare
Temmer, M.; Veronig, A. M.; Gömöry, P. +2 more
Aims: We study the response of the solar atmosphere during a GOES M1.6 flare using spectroscopic and imaging observations. In particular, we examine the evolution of the mass flows and electron density together with the energy input derived from hard X-ray (HXR) in the context of chromospheric evaporation.
Methods: We analyzed high-caden…
Feature-tailored spectroscopic analysis of the supernova remnant Puppis A in X-rays
Luna, G. J. M.; Giacani, E.; Smith, M. J. S. +2 more
We introduce a distinct method for performing spatially resolved spectral analysis of astronomical sources with highly structured X-ray emission. The method measures the surface brightness of neighboring pixels to adaptively size and shape each region, thus the spectra from the bright and faint filamentary structures evident in the broadband image…
The fundamental parameters of the roAp star HD 24712. A rapidly oscillator at the red edge of the instability strip
Shulyak, D.; ten Brummelaar, T. A.; Perraut, K. +4 more
Context. There is still a debate about the nature of the mechanism that causes the pulsation excitation of the rapidly oscillating Ap stars that oscillate above the highest theoretically acoustic frequency. HD 24712 is a good test case for such a study because it is bright, its parallax accurately determined, and its frequency spectrum is well kno…
Stellar twins determine the distance of the Pleiades
Casey, Andrew R.; Hawkins, Keith; Jofré, Paula +5 more
Since the release of the Hipparcos catalogue in 1997, the distance to the Pleiades open cluster has been heavily debated. The distance obtained from Hipparcos and those by alternative methods differ by 10 to 15%. As accurate stellar distances are key to understanding stellar structure and evolution, this dilemma puts the validity of some stellar e…