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Source-plane Reconstruction of the Giant Gravitational Arc in A2667: A Candidate Wolf-Rayet Galaxy at z ~ 1
Richard, Johan; Izzo, Luca; Jullo, Eric +3 more
We present a new analysis of Hubble Space Telescope, Spitzer Space Telescope, and Very Large Telescope imaging and spectroscopic data of a bright lensed galaxy at z = 1.0334 in the lensing cluster A2667. Using this high-resolution imaging, we present an updated lens model that allows us to fully understand the lensing geometry and reconstruct the …
Proving strong magnetic fields near to the central black hole in the quasar PG0043+039 via cyclotron lines
Schartel, N.; Rodríguez-Pascual, P. M.; Santos-Lleó, M. +3 more
Context. The optical luminous quasar PG0043+039 has not been detected before in deep X-ray observations indicating the most extreme optical-to-X-ray slope index αox of all quasars.
Aims: This study aims to detect PG0043+039 in a deep X-ray exposure. Furthermore, we wanted to check out whether this object shows specific spectral pro…
Time series with tailored nonlinearities
Räth, C.; Laut, I.
It is demonstrated how to generate time series with tailored nonlinearities by inducing well-defined constraints on the Fourier phases. Correlations between the phase information of adjacent phases and (static and dynamic) measures of nonlinearities are established and their origin is explained. By applying a set of simple constraints on the phase…
Optical observations of comet 67P/Churyumov-Gerasimenko with the Nordic Optical Telescope. Comet activity before the solar conjunction
Snodgrass, C.; Schulz, R.; Nilsson, K. +4 more
Context. 67P/Churyumov-Gerasimenko (67P) is a short-period Jupiter-family comet that was chosen as a target for the Rosetta mission by the European Space Agency (ESA). Monitoring of 67P with the Nordic Optical Telescope (NOT; La Palma, Spain) intends to aid this mission by providing ground-based reference information about the overall activity of …
A spatial-correlation analysis of the cubic 3-torus topology based on the Planck 2013 data
Aurich, R.
Spatial correlations of the cubic 3-torus topology are analysed using the Planck 2013 data. The spatial-correlation method for detecting multiply connected spaces is based on the fact that positions on the cosmic microwave background (CMB) sky, that are separated by large angular distances, can be spatially much nearer according to a hypothesized …
Cycle Length Dependence of Stellar Magnetic Activity and Solar Cycle 23
Lee, Jeongwoo; Choi, Hwajin; Oh, Suyeon +3 more
Solar cycle (SC) 23 was extraordinarily long with remarkably low magnetic activity. We have investigated whether this is a common behavior of solar-type stars. From the Ca ii H and K line intensities of 111 stars observed at Mount Wilson Observatory from 1966 to 1991, we have retrieved data of all 23 G-type stars and recalculated their cycle lengt…
Observations of Galactic star-forming regions with the Cosmic Background Imager at 31 GHz
Dickinson, C.; Pearson, T. J.; Readhead, A. C. S. +6 more
Studies of the diffuse Galactic radio emission are interesting both for better understanding the physical conditions in our Galaxy and for minimizing the contamination in cosmological measurements. Motivated by this, we present Cosmic Background Imager 31 GHz observations of the Galactic regions NGC 6357, NGC 6334, W51 and W40 at ∼4.5 arcmin resol…
Modelling warm absorption in HST/COS spectrum of Mrk 290 with XSTAR
Kriss, G. A.; Kallman, T. R.; Zhang, S. N. +4 more
We present a new method to model an HST/COS (Hubble Space Telescope/Cosmic Origins Spectrograph) spectrum, aimed to analyse intrinsic UV absorption from the outflow of Mrk 290, a Seyfert I galaxy. We use newly updated XSTAR to generate photoionization models for the intrinsic absorption from the active galactic nuclei (AGN) outflow, the line emiss…
Evolution of solar active regions: Detecting the emergence of new magnetic field through multifractal segmentation
Golovko, A. A.; Salakhutdinova, I. I.
New emerging magnetic flux is identifed using a multifractal segmentation method used to investigate regularities in the evolution of active regions and activity complexes. The SOLIS, MDI SOHO, and SOT Hinode magnetograms were used. Observations of the active region NOAA 10488 on October 26-28, 2003 indicate considerable variability of areas of ne…
Infrared-faint radio sources remain undetected at far-infrared wavelengths. Deep photometric observations using the Herschel Space Observatory
Norris, R. P.; Leipski, C.; Spitler, L. R. +3 more
Context. Showing 1.4 GHz flux densities in the range of a few to a few tens of mJy, infrared-faint radio sources (IFRS) are a type of galaxy characterised by faint or absent near-infrared counterparts and consequently extreme radio-to-infrared flux density ratios up to several thousand. Recent studies showed that IFRS are radio-loud active galacti…