Search Publications
Searching for sterile neutrinos in dynamical dark energy cosmologies
Feng, Lu; Zhang, Jing-Fei; Zhang, Xin
We investigate how the dark energy properties change the cosmological limits on sterile neutrino parameters by using recent cosmological observations. We consider the simplest dynamical dark energy models, the wCDM model and the holographic dark energy (HDE) model, to make an analysis. The cosmological observations used in this work include the Pl…
Evidence of Environmental Quenching at Redshift z ≈ 2
Ferguson, Henry C.; Giavalisco, Mauro; Ji, Zhiyuan +5 more
We report evidence of environmental quenching among galaxies at redshifts of ≈2, namely the probability that a galaxy quenches its star formation activity is enhanced in the regions of space in proximity of other quenched, more massive galaxies. The effect is observed as strong clustering of quiescent galaxies around quiescent galaxies on angular …
Ejection processes in the young open cluster NGC 2264. A study of the [OI]λ6300Å emission line
Dougados, C.; Bouvier, J.; Alencar, S. H. P. +2 more
Context. Statistical studies of the spectral signatures of jets and winds in young stars are crucial to characterize outflows and understand their impact on disk and stellar evolution. The young, open cluster NGC 2264 contains hundreds of well-characterized classical T Tauri stars (CTTS), being thus an ideal site for these statistical studies. Its…
Expansion patterns and parallaxes for planetary nebulae
Balick, B.; Schönberner, D.; Jacob, R.
Aims: We aim to determine individual distances to a small number of rather round, quite regularly shaped planetary nebulae by combining their angular expansion in the plane of the sky with a spectroscopically measured expansion along the line of sight.
Methods: We combined up to three epochs of Hubble Space Telescope imaging data and det…
Accreting, highly magnetized neutron stars at the Eddington limit: a study of the 2016 outburst of SMC X-3
Vasilopoulos, Georgios; Koliopanos, Filippos
Aims: We study the temporal and spectral characteristics of SMC X-3 during its recent (2016) outburst to probe accretion onto highly magnetized neutron stars (NSs) at the Eddington limit.
Methods: We obtained XMM-Newton observations of SMC X-3 and combined them with long-term observations by Swift. We performed a detailed analysis of the…
Gaia Data Release 2. Calibration and mitigation of electronic offset effects in the data
Smith, M.; Allende Prieto, C.; Boudreault, S. +30 more
Context. The European Space Agency's Gaia satellite was launched into orbit around L2 in December 2013. This ambitious mission has strict requirements on residual systematic errors resulting from instrumental corrections in order to meet a design goal of sub-10 microarcsecond astrometry. During the design and build phase of the science instruments…
Quantifying the AGN-driven outflows in ULIRGs (QUADROS) - II. Evidence for compact outflow regions from HST [O III] imaging observations
Rose, M.; Chiaberge, M.; Batcheldor, D. +7 more
The true importance of the warm, AGN-driven outflows for the evolution of galaxies remains uncertain. Measurements of the radial extents of the outflows are key for quantifying their masses and kinetic powers, and also establishing whether the AGN outflows are galaxy-wide. Therefore, as part of a larger project to investigate the significance of w…
The GALAH survey and Gaia DR2: (non-)existence of five sparse high-latitude open clusters
Lewis, Geraint F.; Ting, Yuan-Sen; Bedding, Timothy R. +21 more
Sparse open clusters can be found at high galactic latitudes where loosely populated clusters are more easily detected against the lower stellar background. Because most star formation takes place in the thin disc, the observed population of clusters far from the Galactic plane is hard to explain. We combined spectral parameters from the GALAH sur…
Hubble Space Telescope Wide Field Camera 3 Identifies an r p = 1 Kpc Dual Active Galactic Nucleus in the Minor Galaxy Merger SDSS J0924+0510 at z = 0.1495
Shen, Yue; Strauss, Michael A.; Greene, Jenny E. +2 more
Kiloparsec-scale dual active galactic nuclei (AGNs) are active supermassive black hole pairs co-rotating in galaxies with separations of less than a few kpc. Expected to be a generic outcome of hierarchical galaxy formation, their frequency and demographics remain uncertain. We have carried out an imaging survey with the Hubble Space Telescope (HS…
SN 2016X: a type II-P supernova with a signature of shock breakout from explosion of a massive red supergiant
Brown, P. J.; McCully, C.; Lin, H. +15 more
We present extensive ultraviolet (UV) and optical photometry, as well as dense optical spectroscopy, for type II Plateau (IIP) supernova SN 2016X that exploded in the nearby (∼15 Mpc) spiral galaxy UGC 08041. The observations span the period from 2 to 180 d after the explosion; in particular, the Swift UV data probably captured the signature of sh…