Search Publications
The molecular complex associated with the Galactic H II region Sh2-90: a possible site of triggered star formation
Zavagno, A.; Samal, M. R.; Ojha, D. K. +6 more
Aims: We investigate the star formation activity in the molecular complex associated with the Galactic H ii region Sh2-90.
Methods: We obtain the distribution of the ionized and cold neutral gas using radio-continuum and Herschel observations. We use near-infrared and Spitzer data to investigate the stellar content of the complex. We dis…
The M 4 Core Project with HST - II. Multiple stellar populations at the bottom of the main sequence
Knigge, C.; van den Berg, M.; Anderson, J. +15 more
The M 4 Core Project with HST is designed to exploit the Hubble Space Telescope (HST) to investigate the central regions of M 4, the Globular Cluster closest to the Sun. In this paper we combine optical and near-infrared photometry to study multiple stellar populations in M 4. We detected two sequences of M-dwarfs containing ∼38 per cent (MSI…
Post-Planck constraints on interacting vacuum energy
Zhao, Gong-Bo; Xu, Lixin; Wang, Yuting +1 more
We present improved constraints on an interacting vacuum model using updated astronomical observations including the first data release from Planck. We consider a model with one dimensionless parameter, α, describing the interaction between dark matter and vacuum energy (with fixed equation of state w=-1). The background dynamics correspond to a g…
The Puzzling Mutual Orbit of the Binary Trojan Asteroid (624) Hektor
Wong, M. H.; Berthier, J.; Kalas, P. +9 more
Asteroids with satellites are natural laboratories to constrain the formation and evolution of our solar system. The binary Trojan asteroid (624) Hektor is the only known Trojan asteroid to possess a small satellite. Based on W. M. Keck adaptive optics observations, we found a unique and stable orbital solution, which is uncommon in comparison to …
The properties of the clumpy torus and BLR in the polar-scattered Seyfert 1 galaxy ESO 323-G77 through X-ray absorption variability
Bianchi, S.; Guainazzi, M.; Jiménez-Bailón, E. +8 more
We report results from multi-epoch (2006-2013) X-ray observations of the polar-scattered Seyfert 1 galaxy ESO 323-G77. The source exhibits remarkable spectral variability from months to years timescales. The observed spectral variability is entirely due to variations of the column density of a neutral absorber towards the intrinsic nuclear continu…
Growth mechanisms and dune orientation on Titan
Lorenz, Ralph D.; Tokano, Tetsuya; Rodriguez, Sébastien +8 more
Dune fields on Titan cover more than 17% of the moon's surface, constituting the largest known surface reservoir of organics. Their confinement to the equatorial belt, shape, and eastward direction of propagation offer crucial information regarding both the wind regime and sediment supply. Herein, we present a comprehensive analysis of Titan's dun…
Explosive Events on a Subarcsecond Scale in IRIS Observations: A Case Study
Doyle, J. G.; Fu, Hui; Madjarska, Maria S. +3 more
We present a study of a typical explosive event (EE) at subarcsecond scale witnessed by strong non-Gaussian profiles with blue- and redshifted emission of up to 150 km s-1 seen in the transition region Si IV 1402.8 Å, and the chromospheric Mg II k 2796.4 Å and C II 1334.5 Å observed by the Interface Region Imaging Spectrograph (IRIS) at…
The return to quiescence of Aql X-1 following the 2010 outburst
D'Avanzo, P.; Campana, S.; Mereghetti, S. +5 more
Aql X-1 is the most prolific low-mass X-ray binary transient hosting a neutron star. In this paper we focus on the return to quiescence following the 2010 outburst of the source. This decay was monitored thanks to 11 pointed observations taken with XMM-Newton, Chandra and Swift. The decay from outburst to quiescence is very fast, with an exponenti…
Using correlations between cosmic microwave background lensing and large-scale structure to measure primordial non-Gaussianity.
Giannantonio, T.; Percival, W. J.
We apply a new method to measure primordial non-Gaussianity, using the cross-correlation between galaxy surveys and the cosmic microwave background (CMB) lensing signal to measure galaxy bias on very large scales, where local-type primordial non-Gaussianity predicts a k2 divergence. We use the CMB lensing map recently published by the P…
Modelling the [Fe II] λ1.644 µm outflow and comparison with H2 and H+ kinematics in the inner 200 pc of NGC 1068
Storchi-Bergmann, T.; Barbosa, F. K. B.; McGregor, P. +2 more
We map the kinematics of the inner (200 pc) narrow-line region (NLR) of the Seyfert 2 galaxy NGC 1068 using the instrument Near-infrared Integral Field Spectrograph and adaptive optics at the Gemini North telescope. Channel maps and position-velocity diagrams are presented at a spatial resolution of ≅8 pc and spectral resolution ∼5300 in the emiss…