Search Publications
The spatial extent of polycyclic aromatic hydrocarbons emission in the Herbig star HD 179218
Rebolo, R.; Wolf, S.; Taha, A. S. +7 more
Aim. We investigate, in the mid-infrared, the spatial properties of the polycyclic aromatic hydrocarbons (PAHs) emission in the disk of HD 179218, an intermediate-mass Herbig star at 300 pc.
Methods: We obtained mid-infrared images in the PAH-1, PAH-2 and Si-6 filters centered at 8.6, 11.3, and 12.5 µm, and N-band low-resolution spectra…
Galaxy evolution in groups. NGC 3447/NGC 3447A: the odd couple in LGG 225
Plana, H.; Marino, A.; Mazzei, P. +3 more
Context. Local Group (LG) analogs (LGAs) are galaxy associations dominated by a few bright spirals reminiscent of the LG. The NGC 3447/NGC 3447A system is a member of the LGG 225 group, a nearby LGA. This system is considered a physical pair composed of an intermediate-luminosity late-type spiral, NGC 3447 itself, and an irregular companion, NGC 3…
The Grism Lens-amplified Survey from Space (GLASS). XII. Spatially Resolved Galaxy Star Formation Histories and True Evolutionary Paths at z > 1
Vulcani, B.; Hoag, A.; Bradač, M. +12 more
Modern data empower observers to describe galaxies as the spatially and biographically complex objects they are. We illustrate this through case studies of four z ∼ 1.3 systems based on deep, spatially resolved, 17-band + G102 + G141 Hubble Space Telescope grism spectrophotometry. Using full-spectrum rest-UV/-optical continuum fitting, we characte…
Probing black hole accretion in quasar pairs at high redshift
Vignali, C.; Gilli, R.; Piconcelli, E. +6 more
Models and observations suggest that luminous quasar activity is triggered by mergers, so it should preferentially occur in the most massive primordial dark matter haloes, where the frequency of mergers is expected to be the highest. Since the importance of galaxy mergers increases with redshift, we identify the high-redshift Universe as the ideal…
Predicted Microlensing Events by Nearby Very-Low-Mass Objects: Pan-STARRS DR1 vs. Gaia DR2
Nielsen, M. B.; Bramich, D. M.
Microlensing events can be used to directly measure the masses of single field stars to a precision of ≈1-10%. The majority of direct mass measurements for stellar and sub-stellar objects typically only come from observations of binary systems. Hence microlensing provides an important channel for direct mass measurements of single stars. The Gaia …
VALES - IV. Exploring the transition of star formation efficiencies between normal and starburst galaxies using APEX/SEPIA Band-5 and ALMA at low redshift
Leiton, R.; Ibar, E.; Xue, Y. Q. +12 more
In this work, we present new the Swedish-ESO PI receiver for the Atacama Pathfinder Experiment APEX/SEPIA Band-5 observations targeting the CO (J = 2-1) emission line of 24 Herschel-detected galaxies at z = 0.1-0.2. Combining this sample with our recent new Valparaíso ALMA Line Emission Survey (VALES), we investigate the star formation efficiencie…
Two new magnetic cataclysmic variables discovered in the 3XMM catalogue
Schwope, A.; Webb, N. A.; Rosen, S. R. +2 more
Context. X-ray catalogues provide a wealth of information on many source types, ranging from compact objects to galaxies, clusters of galaxies, stars, and even planets. Thanks to the huge volume of X-ray sources provided in the 3XMM catalogue, along with many source specific products, many new examples from rare classes of sources can be identifie…
Nonlobe Reconnection at the Earth's Magnetopause for Northward IMF
Lavraud, B.; Fuselier, S. A.; Trattner, K. J. +2 more
Under northward interplanetary magnetic field conditions, magnetic reconnection at the Earth's magnetopause is usually thought to operate through the merging of magnetosheath magnetic field lines and open magnetic field lines from the magnetospheric lobe. However, reconnection also occurs between magnetosheath field lines and closed magnetic field…
Asteroseismology of KIC 7107778: a binary comprising almost identical subgiants
Bi, Shaolan; Li, Yaguang; Corsaro, Enrico +5 more
We analyse an asteroseismic binary system: KIC 7107778, a non-eclipsing, unresolved target, with solar-like oscillations in both components. We used Kepler short cadence time series spanning nearly 2 yr to obtain the power spectrum. Oscillation mode parameters were determined using Bayesian inference and a nested sampling Monte Carlo algorithm wit…
Simultaneous VLBI Astrometry of H2O and SiO Masers toward the Semiregular Variable R Crateris
Kim, Dong-Jin; Rioja, María J.; Dodson, Richard +7 more
We obtained, for the first time, astrometrically registered maps of the 22.2 GHz H2O and 42.8, 43.1, and 86.2 GHz SiO maser emission toward the semiregular b-type variable (SRb) R Crateris, at three epochs (2015 May 21, and 2016 January 7 and 26) using the Korean Very-long-baseline Interferometry Network. The SiO masers show a ring-like…