Search Publications
Tracking the energetics of the non-thermal disc-corona-jet in the very high state GX 339 - 4
Done, C.; Kubota, A.
The dramatic hard-soft spectral transition in black hole binaries is important as it is associated with the collapse of the jet and with the strongest low-frequency quasi-periodic oscillations (QPOs). These transition spectra (intermediate and very high state: VHS) are complex, with soft but distinctly non-thermal Comptonization which merges smoot…
Using radio stars to link the Gaia and VLBI reference frames
Malkin, Zinovy
A possible method for linking the optical Gaia Celestial Reference Frame (GCRF) to the VLBI-based International Celestial Reference Frame (ICRF) is to use radio stars in a manner similar to that in the linking of the Hipparcos Celestial Reference Frame (HCRF) to ICRF. In this work, an obtainable accuracy of the orientation angles between GCRF and …
Analysis of a spatially deconvolved solar pore
Ichimoto, K.; Suematsu, Y.; Katsukawa, Y. +3 more
Solar pores are active regions with large magnetic field strengths and apparent simple magnetic configurations. Their properties resemble the ones found for the sunspot umbra although pores do not show penumbra. Therefore, solar pores present themselves as an intriguing phenomenon that is not completely understood. We examine in this work a solar …
Magellan LDSS3 emission confirmation of galaxies hosting metal-rich Lyman α absorption systems
Bowen, David V.; York, Donald G.; Florian, Michael +5 more
Using the Low Dispersion Survey Spectrograph 3 at the Magellan II Clay Telescope, we target candidate absorption host galaxies detected in deep optical imaging (reaching limiting apparent magnitudes of 23.0-26.5 in g, r, I, and z filters) in the fields of three QSOs, each of which shows the presence of high metallicity, high N_{H I} absorption sys…
The interstellar medium in Andromeda's dwarf spheroidal galaxies - I. Content and origin of the interstellar dust
De Looze, Ilse; Baes, Maarten; Bendo, George J. +8 more
Dwarf spheroidal galaxies are among the most numerous galaxy population in the Universe, but their main formation and evolution channels are still not well understood. The three dwarf spheroidal satellites (NGC 147, NGC 185, and NGC 205) of the Andromeda galaxy are characterized by very different interstellar medium properties, which might suggest…
Dark matter fraction of low-mass cluster members probed by galaxy-scale strong lensing
Grillo, C.; Balestra, I.; Rosati, P. +8 more
We present a strong lensing system, composed of four multiple images of a source at z = 2.387, created by two lens galaxies, G1 and G2, belonging to the galaxy cluster MACS J1115.9+0129 at z = 0.353. We use observations taken as part of the Cluster Lensing and Supernova survey with Hubble, and its spectroscopic follow-up programme at the Very Larg…
The circumstellar disc of FS Tau B - a self-consistent model based on observations in the mid-infrared with NACO
Kirchschlager, Florian; Wolf, Sebastian; Madlener, David
Protoplanetary discs are a byproduct of the star formation process. In the dense mid-plane of these discs, planetesimals and planets are expected to form. The first step in planet formation is the growth of dust particles from submicrometre-sized grains to macroscopic mm-sized aggregates. The grain growth is accompanied by radial drift and vertica…
The dust properties and physical conditions of the interstellar medium in the LMC massive star-forming complex N11
Lebouteiller, V.; Madden, S. C.; Galliano, F. +19 more
We combine Spitzer and Herschel data of the star-forming region N11 in the Large Magellanic Cloud (LMC) to produce detailed maps of the dust properties in the complex and study their variations with the interstellar-medium conditions. We also compare Atacama Pathfinder EXperiment/Large APEX Bolometer Camera (APEX/LABOCA) 870 µm observations …
High-energy properties of the high-redshift flat spectrum radio quasar PKS 2149-306
D'Ammando, F.; Orienti, M.
We investigate the γ-ray and X-ray properties of the flat spectrum radio quasar PKS 2149-306 at redshift z = 2.345. A strong γ-ray flare from this source was detected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope satellite in 2013 January, reaching on January 20 a daily peak flux of (301 ± 36) × 10-8 ph cm
A newly discovered radio halo in merging cluster MACS J2243.3-0935
Han, J. L.; Wen, Z. L.; Oozeer, N. +2 more
We report the discovery of a radio halo in the massive merging cluster MACSJ2243.3-0935, as well as a new radio relic candidate, using the Giant Meterwave Radio Telescope and the Karoo Array Telescope-7 telescope. The radio halo is coincident with the cluster X-ray emission and has a largest linear scale of approximately 0.9 Mpc. We measure a flux…