Search Publications
An abundance analysis from the STIS-HST UV spectrum of the non-magnetic Bp star HR 6000
Leone, F.; Castelli, F.; Catanzaro, G. +2 more
Context. The sharp-line spectrum of the non-magnetic, main-sequence Bp star HR 6000 has peculiarities that distinguish it from those of the HgMn stars with which it is sometimes associated. The position of the star close to the center of the Lupus 3 molecular cloud, whose estimated age is on the order of 9.1 ± 2.1 Myr, has lead to the hypothesis t…
The 34S/32S isotopic ratio measured in the dust of comet 67P/Churyumov-Gerasimenko by Rosetta/COSIMA
Hilchenbach, M.; Hornung, K.; Kissel, J. +4 more
The isotopic ratio 34S/32S has been measured in cometary gas for a few comets, but it has only been measured in cometary dust by stardust. The dust measurements find a value of the ratio that is consistent with the Vienna Canyon Diablo Troilite value of 0.0442 within errors, but there is more spread in the values from cometar…
Ultrafast outflows in ultraluminous X‑ray sources
Pinto, C.; Walton, D.; Fabian, A. +1 more
Ultraluminous X-ray sources (ULXs) are bright extragalactic sources with X-ray luminosities above 10^39 erg/s powered by accretion onto compact objects. According to the first studies performed with XMM-Newton ULXs seemed to be excellent candidates to host intermediate-mass black holes (10^2-4 solar masses). However, in the last years the interpre…
Three-dimensional illumination and thermal model of the Abydos region on comet 67P/Churyumov-Gerasimenko
Spohn, Tilman; Finke, Felix; Jorda, Laurent +9 more
On 2014 November 12 Rosetta's comet lander Philae arrived on the surface of Comet 67P/Churyumov-Gerasimenko. Among the data collected by the instruments on board are images from the panorama camera CIVA and the down looking camera ROLIS, as well as temperature measurements recorded by the sensors of the MUPUS experiment and by various housekeeping…
Herschel and Hubble Study of a Lensed Massive Dusty Starbursting Galaxy at z ∼ 3
Ivison, R. J.; Frayer, D. T.; Cooray, A. +19 more
We present the results of combined deep Keck/NIRC2, HST/WFC3 near-infrared, and Herschel far-infrared observations of an extremely star-forming dusty lensed galaxy identified from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS J133542.9+300401). The galaxy is gravitationally lensed by a massive WISE-identified galaxy cluster at z …
The spectroscopic indistinguishability of red giant branch and red clump stars
Masseron, T.; Hawkins, K.
Context. Stellar spectroscopy provides useful information on the physical properties of stars such as effective temperature, metallicity and surface gravity. However, those photospheric characteristics are often hampered by systematic uncertainties. The joint spectro-sismo project (APOGEE+Kepler, aka APOKASC) of field red giants has revealed a puz…
Cosmological implications of different baryon acoustic oscillation data
Li, Miao; Wang, Shuang; Hu, YaZhou
In this work, we explore the cosmological implications of different baryon acoustic oscillation (BAO) data, including the BAO data extracted by using the spherically averaged one-dimensional galaxy clustering (GC) statistics (hereafter BAO1) and the BAO data obtained by using the anisotropic two-dimensional GC statistics (hereafter BAO2). To make …
Unveiling slim accretion disc in AGN through X-ray and Infrared observations
Kaspi, Shai; Ho, Luis C.; Bian, Wei-Hao +7 more
In this work, which is a continuation of Castelló-Mor et al., we present new X-ray and infrared (IR) data for a sample of active galactic nuclei (AGN) covering a wide range in Eddington ratio over a small luminosity range. In particular, we rigorously explore the dependence of the optical-to-X-ray spectral index αOX and the IR-to-optica…
Magnetic Separatrix as the Source Region of the Plasma Supply for an Active-region Filament
Cao, Wenda; Yang, K.; Chen, P. F. +2 more
Solar filaments can be formed via chromospheric evaporation followed by condensation in the corona or by the direct injection of cool plasma from the chromosphere to the corona. We here confirm with high-resolution Hα data observed by the 1.6 m New Solar Telescope of the Big Bear Solar Observatory on 2015 August 21 that an active-region filament i…
X-ray observations of FO Aqr during the 2016 low state
Mukai, K.; Garnavich, P. M.; Kennedy, M. R. +5 more
We present the first ever X-ray data taken of an intermediate polar, FO Aquarii (FO Aqr), when in a low accretion state and during the subsequent recovery. Both the Swift and Chandra X-ray data taken during the low accretion state in 2016 July show a softer spectrum when compared to archival data taken when FO Aqr was in a high state. The X-ray sp…