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The impact from survey depth and resolution on the morphological classification of galaxies
Cepa, J.; Infante, L.; Molino, A. +28 more
We consistently analyse for the first time the impact of survey depth and spatial resolution on the most used morphological parameters for classifying galaxies through non-parametric methods: Abraham and Conselice-Bershady concentration indices, Gini, M20 moment of light, asymmetry, and smoothness. Three different non-local data sets are used, Adv…
SWAP Observations of Post-flare Giant Arches in the Long-Duration 14 October 2014 Solar Eruption
West, Matthew J.; Seaton, Daniel B.
On 2014 October 14 the Sun Watcher with Active Pixels and Image Processing EUV solar telescope on board the Project for On Board Autonomy 2 spacecraft observed an eruption that led to the formation of perhaps the largest post-eruptive loop system seen in the solar corona in solar cycle 24. The initial eruption occurred at about 18:30 UT on October…
Calibration and in-orbit performance of the reflection grating spectrometer onboard XMM-Newton
Kaastra, J. S.; Raassen, A. J. J.; de Vries, C. P. +6 more
Context. XMM-Newton was launched on 10 December 1999 and has been operational since early 2000. One of the instruments onboard XMM-Newton is the reflection grating spectrometer (RGS). Two identical RGS instruments are available, with each RGS combining a reflection grating assembly and a camera with charge-coupled devices to record the spectra.
Evidence for crater ejecta on Venus tessera terrain from Earth-based radar images
Campbell, Donald B.; Nolan, Michael C.; Campbell, Bruce A. +3 more
We combine Earth-based radar maps of Venus from the 1988 and 2012 inferior conjunctions, which had similar viewing geometries. Processing of both datasets with better image focusing and co-registration techniques, and summing over multiple looks, yields maps with 1-2 km spatial resolution and improved signal to noise ratio, especially in the weake…
The Chandra Local Volume Survey. I. The X-Ray Point Source Populations of NGC 55, NGC 2403, and NGC 4214
Dalcanton, J. J.; Skillman, E. D.; Kong, A. K. H. +7 more
We present comprehensive X-ray point source catalogs of NGC 55, NGC 2403, and NGC 4214 as part of the Chandra Local Volume Survey. The combined archival observations have effective exposure times of 56.5 ks, 190 ks, and 79 ks for NGC 55, NGC 2403, and NGC 4214, respectively. When combined with our published catalogs for NGC 300 and NGC 404, our su…
Radio relics tracing the projected mass distribution in CIZA J2242.8+5301*
Umetsu, Keiichi; Fujita, Yutaka; Okabe, Nobuhiro +4 more
We present a weak-lensing analysis for a merging galaxy cluster, CIZA J2242.8+5301, which hosts double radio relics, using three-band Subaru/Suprime-Cam imaging (Br'z'). Since the lifetime of dark matter halos colliding into clusters is longer than that of X-ray emitting gas halos, weak-lensing analysis is a powerful method t…
The changing UV and X-ray properties of the Of?p star CPD -28°2561
Wade, Gregg A.; Walborn, Nolan R.; Nazé, Yaël +4 more
The Of?p star CPD -28°2561 was monitored at high energies with XMM-Newton and HST. In X-rays, this magnetic oblique rotator displays bright and hard emission that varies by ∼55 per cent with rotational phase. These changes occur in phase with optical variations, as expected for magnetically confined winds; there are two maxima and two minima in X-…
When is pile-up important in the XMM-Newton EPIC cameras?
Guainazzi, M.; Rodriguez-Pascual, P.; Stuhlinger, M. +2 more
Context. Pile-up in X-ray charged couple device (CCD) detectors is defined as the reconstruction of independent events in the same detection cell as a single event during a read-out cycle. Pile-up can seriously compromise the spectral performance, modifying both the flux and the spectral shape of celestial sources.
Aims: In this paper we defi…
The Gaia spectrophotometric standard stars survey: II. Instrumental effects of six ground-based observing campaigns
Jordi, C.; Figueras, F.; Marinoni, S. +16 more
The Gaia SpectroPhotometric Standard Stars (SPSS) survey started in 2006, was awarded almost 450 observing nights and accumulated almost 100 000 raw data frames with both photometric and spectroscopic observations. Such large observational effort requires careful, homogeneous, and automatic data reduction and quality control procedures. In this pa…
A variable-density absorption event in NGC 3227 mapped with Suzaku and Swift
Guainazzi, M.; Elvis, M.; Miniutti, G. +15 more
Context. The morphology of the circumnuclear gas accreting onto supermassive black holes in Seyfert galaxies remains a topic of much debate. As the innermost regions of active galactic nuclei (AGN) are spatially unresolved, X-ray spectroscopy, and in particular line-of-sight absorption variability, is a key diagnostic to map out the distribution o…