Search Publications
Molecular outflows in local galaxies: Method comparison and a role of intermittent AGN driving
Lutz, D.; Genzel, R.; Maiolino, R. +19 more
We report new detections and limits from a NOEMA and ALMA CO(1-0) search for molecular outflows in 13 local galaxies with high far-infrared surface brightness, and combine these with local universe CO outflow results from the literature. The CO line ratios and spatial outflow structure of our targets provide some constraints on the conversion step…
Stormy water on Mars: The distribution and saturation of atmospheric water during the dusty season
Montmessin, Franck; Belyaev, Denis A.; Fedorova, Anna A. +19 more
The loss of water from Mars to space is thought to result from the transport of water to the upper atmosphere, where it is dissociated to hydrogen and escapes the planet. Recent observations have suggested large, rapid seasonal intrusions of water into the upper atmosphere, boosting the hydrogen abundance. We use the Atmospheric Chemistry Suite on…
Kiloparsec-scale ALMA Imaging of [C II] and Dust Continuum Emission of 27 Quasar Host Galaxies at z ∼ 6
Carilli, Chris; Fan, Xiaohui; Neeleman, Marcel +12 more
We present a study of the [C II] 158 µm line and underlying far-infrared (FIR) continuum emission of 27 quasar host galaxies at z ∼ 6, traced by the Atacama Large Millimeter/submillimeter Array at a spatial resolution of ∼1 physical kpc. The [C II] emission in the bright, central regions of the quasars have sizes of 1.0-4.8 kpc. The dust con…
CME-CME Interactions as Sources of CME Geoeffectiveness: The Formation of the Complex Ejecta and Intense Geomagnetic Storm in 2017 Early September
Veronig, Astrid M.; Dumbović, Mateja; Temmer, Manuela +9 more
Coronal mass ejections (CMEs) are the primary sources of intense disturbances at Earth, where their geoeffectiveness is largely determined by their dynamic pressure and internal magnetic field, which can be significantly altered during interactions with other CMEs in interplanetary space. We analyze three successive CMEs that erupted from the Sun …
Synthetic Gaia Surveys from the FIRE Cosmological Simulations of Milky Way-mass Galaxies
Faucher-Giguère, Claude-André; Sharma, Sanjib; Hopkins, Philip F. +6 more
With Gaia Data Release 2, the astronomical community is entering a new era of multidimensional surveys of the Milky Way. This new phase-space view of our Galaxy demands new tools for comparing observations to simulations of Milky Way-mass galaxies in a cosmological context, to test the physics of both dark matter and galaxy formation. We present a…
Ages and kinematics of chemically selected, accreted Milky Way halo stars
Hawkins, Keith; Jofré, Paula; Das, Payel
We exploit the [Mg/Mn]-[Al/Fe] chemical abundance plane to help identify nearby halo stars in the 14th data release from the APOGEE survey that have been accreted on to the Milky Way. Applying a Gaussian Mixture Model, we find a `blob' of 856 likely accreted stars, with a low disc contamination rate of ∼7 per cent. Cross-matching the sa…
Ammonium salts are a reservoir of nitrogen on a cometary nucleus and possibly on some asteroids
Longobardo, Andrea; Palomba, Ernesto; Schmitt, Bernard +29 more
The measured nitrogen-to-carbon ratio in comets is lower than for the Sun, a discrepancy which could be alleviated if there is an unknown reservoir of nitrogen in comets. The nucleus of comet 67P/Churyumov-Gerasimenko exhibits an unidentified broad spectral reflectance feature around 3.2 micrometers, which is ubiquitous across its surface. On the …
Dynamical Relics of the Ancient Galactic Halo
Zhao, Gang; Myeong, G. C.; Evans, N. W. +11 more
We search for dynamical substructures in the LAMOST DR3 very metal-poor (VMP) star catalog. After cross-matching with Gaia DR2, there are ∼3300 VMP stars with available high-quality astrometric information that have halo-like kinematics. We apply a method based on the self-organizing map StarGO to find groups clustered in the 4D space of orbital e…
Gravity-mode period spacings and near-core rotation rates of 611 γ Doradus stars with Kepler
Li, Gang; Bedding, Timothy R.; Antoci, Victoria +4 more
We report our survey of γ Dor stars from the 4-yr Kepler mission. These stars pulsate mainly in g modes and r modes, showing period-spacing patterns in the amplitude spectra. The period-spacing patterns are sensitive to the chemical composition gradients and the near-core rotation, hence they are essential for understanding the stellar interior. W…
The mass of our Milky Way
Ishigaki, Miho N.; Cautun, Marius; Wang, WenTing +2 more
We perform an extensive review of the numerous studies and methods used to determine the total mass of the Milky Way. We group the various studies into seven broad classes according to their modeling approaches. The classes include: i) estimating Galactic escape velocity using high velocity objects; ii) measuring the rotation curve through termina…