Search Publications

Yule-Simpson's paradox in Galactic Archaeology
DOI: 10.1093/mnras/stz1239 Bibcode: 2019MNRAS.487.3946M

Guiglion, G.; Anders, F.; Chiappini, C. +7 more

Simpson's paradox, or Yule-Simpson effect, arises when a trend appears in different subsets of data but disappears or reverses when these subsets are combined. We describe here seven cases of this phenomenon for chemo-kinematical relations believed to constrain the Milky Way disc formation and evolution. We show that interpreting trends in relatio…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 41
ASKAP detection of periodic and elliptically polarized radio pulses from UV Ceti
DOI: 10.1093/mnras/stz1684 Bibcode: 2019MNRAS.488..559Z

Kaplan, David L.; Lenc, Emil; Phillips, Chris +9 more

Active M dwarfs are known to produce bursty radio emission, and multiwavelength studies have shown that solar-like magnetic activity occurs in these stars. However, coherent bursts from active M dwarfs have often been difficult to interpret in the solar activity paradigm. We present Australian Square Array Pathfinder (ASKAP) observations of UV Cet…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 41
Chemical and kinematic structure of extremely high-velocity molecular jets in the Serpens Main star-forming region
DOI: 10.1051/0004-6361/201935409 Bibcode: 2019A&A...632A.101T

Hull, Charles L. H.; Le Gouellec, Valentin J. M.; van Dishoeck, Ewine F. +3 more

Context. Outflows are one of the first signposts of ongoing star formation. The fastest molecular component of protostellar outflows, extremely high-velocity (EHV) molecular jets, are still puzzling since they are seen only rarely. As they originate deep inside the embedded protostar-disk system, they provide vital information about the outflow-la…

2019 Astronomy and Astrophysics
Herschel 41
A deep groundwater origin for recurring slope lineae on Mars
DOI: 10.1038/s41561-019-0327-5 Bibcode: 2019NatGe..12..235A

Heggy, Essam; Abotalib, Abotalib Z.

The recurring slope lineae on Mars have been hypothesized to originate from snow melting, deliquescence, dry flow or shallow groundwater. Except for the dry flow origin, these hypotheses imply the presence of surficial or near-surface volatiles, placing the exploration and characterization of potential habitable environments within the reach of ex…

2019 Nature Geoscience
MEx 41
Kinetic Turbulence in Astrophysical Plasmas: Waves and/or Structures?
DOI: 10.1103/PhysRevX.9.031037 Bibcode: 2019PhRvX...9c1037G

Chen, Christopher H. K.; Grošelj, Daniel; Mallet, Alfred +3 more

The question of the relative importance of coherent structures and waves has for a long time attracted a great deal of interest in astrophysical plasma turbulence research, with a more recent focus on kinetic scale dynamics. Here we utilize high-resolution observational and simulation data to investigate the nature of waves and structures emerging…

2019 Physical Review X
Cluster 41
The SOPHIE search for northern extrasolar planets. XIV. A temperate (Teq 300 K) super-earth around the nearby star Gliese 411
DOI: 10.1051/0004-6361/201935019 Bibcode: 2019A&A...625A..17D

Bouchy, F.; Deleuil, M.; Moutou, C. +33 more

Periodic radial velocity variations in the nearby M-dwarf star Gl 411 are reported, based on measurements with the SOPHIE spectrograph. Current data do not allow us to distinguish between a 12.95-day period and its one-day alias at 1.08 days, but favour the former slightly. The velocity variation has an amplitude of 1.6 m s-1, making th…

2019 Astronomy and Astrophysics
XMM-Newton 41
The chemical composition of HIP 34407/HIP 34426 and other twin-star comoving pairs
DOI: 10.1093/mnras/stz2709 Bibcode: 2019MNRAS.490.2448R

Lambert, D. L.; Endl, M.; Meléndez, J. +4 more

We conducted a high-precision elemental abundance analysis of the twin-star comoving pair HIP 34407/HIP 34426. With mean error of 0.013 dex in the differential abundances (Δ[X/H]), a significant difference was found: HIP 34407 is more metal rich than HIP 34426. The elemental abundance differences correlate strongly with condensation temperature, w…

2019 Monthly Notices of the Royal Astronomical Society
AKARI Gaia 41
A Census of Early-phase High-mass Star Formation in the Central Molecular Zone
DOI: 10.3847/1538-4365/ab4258 Bibcode: 2019ApJS..244...35L

Ott, Jürgen; Lu, Xing; Henshaw, Jonathan D. +13 more

We present new observations of the C-band continuum emission and masers to assess high-mass (>8 {M}) star formation at early evolutionary phases in the inner 200 pc of the Central Molecular Zone (CMZ) of the Galaxy. The continuum observation is complete to free-free emission from stars above 10-11 {M} in 91% of the cov…

2019 The Astrophysical Journal Supplement Series
Gaia eHST 41
The diverse galaxy counts in the environment of high-redshift massive black holes in Horizon-AGN
DOI: 10.1093/mnras/stz2105 Bibcode: 2019MNRAS.489.1206H

Somerville, Rachel S.; Volonteri, Marta; Habouzit, Mélanie +4 more

High-redshift quasars are believed to reside in highly biased regions of the Universe, where black hole growth is sustained by an enhanced number of mergers and by being at the intersection of filaments bringing fresh gas. This assumption should be supported by an enhancement of the number counts of galaxies in the field of view of quasars. While …

2019 Monthly Notices of the Royal Astronomical Society
eHST 41
The power spectrum of the Lyman-α Forest at z < 0.5
DOI: 10.1093/mnras/stz344 Bibcode: 2019MNRAS.486..769K

Hennawi, Joseph F.; Tripp, Todd M.; Prochaska, J. Xavier +7 more

We present new measurements of the flux power-spectrum P(k) of the z < 0.5 H I Lyman-α Forest spanning scales k ∼ 0.001-0.1 s km^{-1}. These results were derived from 65 far-ultraviolet quasar spectra (resolution R ∼ 18 000) observed with the Cosmic Origin Spectrograph (COS) on board the Hubble Space Telescope. The analysis required careful mas…

2019 Monthly Notices of the Royal Astronomical Society
eHST 41