Search Publications

The Milky Way Cepheid Leavitt law based on Gaia DR2 parallaxes of companion stars and host open cluster populations
DOI: 10.1051/0004-6361/202038633 Bibcode: 2020A&A...643A.115B

Mérand, Antoine; Riess, Adam G.; Breuval, Louise +12 more


Aims: Classical Cepheids provide the foundation for the empirical extragalactic distance ladder. Milky Way Cepheids are the only stars in this class accessible to trigonometric parallax measurements. However, the parallaxes of Cepheids from the second Gaia data release (GDR2) are affected by systematics because of the absence of chromaticity …

2020 Astronomy and Astrophysics
Gaia eHST 66
Observed sizes of planet-forming disks trace viscous spreading
DOI: 10.1051/0004-6361/202037673 Bibcode: 2020A&A...640A...5T

van Dishoeck, E. F.; Rosotti, G.; Trapman, L. +2 more

Context. The evolution of protoplanetary disks is dominated by the conservation of angular momentum, where the accretion of material onto the central star is fed by the viscous expansion of the outer disk or by disk winds extracting angular momentum without changing the disk size. Studying the time evolution of disk sizes therefore allows us to di…

2020 Astronomy and Astrophysics
Gaia 66
The population of hot subdwarf stars studied with Gaia. III. Catalogue of known hot subdwarf stars: Data Release 2
DOI: 10.1051/0004-6361/202037526 Bibcode: 2020A&A...635A.193G

Geier, S.

In light of substantial new discoveries of hot subdwarfs by ongoing spectroscopic surveys and the availability of new all-sky data from ground-based photometric surveys and the Gaia mission Data Release 2, we compiled an updated catalogue of the known hot subdwarf stars. The catalogue contains 5874 unique sources including 528 previously unknown h…

2020 Astronomy and Astrophysics
Gaia 65
Interpreting the Spitzer/IRAC colours of 7 ≤ z ≤ 9 galaxies: distinguishing between line emission and starlight using ALMA
DOI: 10.1093/mnras/staa2085 Bibcode: 2020MNRAS.497.3440R

Laporte, N.; Ellis, R. S.; Roberts-Borsani, G. W.

Prior to the launch of JWST, Spitzer/IRAC photometry offers the only means of studying the rest-frame optical properties of z >7 galaxies. Many such high-redshift galaxies display a red [3.6]-[4.5] micron colour, often referred to as the 'IRAC excess', which has conventionally been interpreted as arising from intense [O III]+H β emission within…

2020 Monthly Notices of the Royal Astronomical Society
eHST 65
All the PAHs: An AKARI-Spitzer Cross-archival Spectroscopic Survey of Aromatic Emission in Galaxies
DOI: 10.3847/1538-4357/abc002 Bibcode: 2020ApJ...905...55L

Baba, Shunsuke; Imanishi, Masatoshi; Lai, Thomas S. -Y. +2 more

We present a large sample of 2.5-38 µm galaxy spectra drawn from a cross-archival comparison in the AKARI-Spitzer Extragalactic Spectral Survey, and investigate a subset of 113 star-forming galaxies with prominent polycyclic aromatic hydrocarbon (PAH) emission spanning a wide range of star formation properties. With AKARI's extended 2.5-5 &m…

2020 The Astrophysical Journal
AKARI 65
unWISE tomography of Planck CMB lensing
DOI: 10.1088/1475-7516/2020/05/047 Bibcode: 2020JCAP...05..047K

Ferraro, Simone; Schlafly, Edward F.; White, Martin +1 more

CMB lensing tomography, or the cross-correlation between CMB lensing maps and large-scale structure tracers over a well-defined redshift range, has the potential to map the amplitude and growth of structure over cosmic time, provide some of the most stringent tests of gravity, and break important degeneracies between cosmological parameters. In th…

2020 Journal of Cosmology and Astroparticle Physics
Gaia 65
Star cluster formation in the most extreme environments: insights from the HiPEEC survey
DOI: 10.1093/mnras/staa2380 Bibcode: 2020MNRAS.499.3267A

Östlin, G.; Larsen, S. S.; Sabbi, E. +14 more

We present the Hubble imaging Probe of Extreme Environments and Clusters (HiPEEC) survey. We fit HST NUV to NIR broad-band and H α fluxes to derive star cluster ages, masses, and extinctions and determine the star formation rate (SFR) of six merging galaxies. These systems are excellent laboratories to trace cluster formation under extreme gas phy…

2020 Monthly Notices of the Royal Astronomical Society
eHST 65
The High-energy Radiation Environment around a 10 Gyr M Dwarf: Habitable at Last?
DOI: 10.3847/1538-3881/abb465 Bibcode: 2020AJ....160..237F

Loyd, R. O. Parke; Kowalski, Adam F.; Brown, Alexander +20 more

Recent work has demonstrated that high levels of X-ray and UV activity on young M dwarfs may drive rapid atmospheric escape on temperate, terrestrial planets orbiting within the habitable zone. However, secondary atmospheres on planets orbiting older, less active M dwarfs may be stable and present more promising candidates for biomarker searches. …

2020 The Astronomical Journal
eHST 65
How comets work: nucleus erosion versus dehydration
DOI: 10.1093/mnras/staa508 Bibcode: 2020MNRAS.493.4039F

Blum, J.; Güttler, C.; Gundlach, B. +3 more

We develop an activity model based on ice sublimation and gas diffusion inside cm-sized pebbles making-up a cometary nucleus. Our model explains cometary activity assuming no free parameters and fixing the nucleus surface temperature Ts, its gradient below the nucleus surface at thermal equilibrium, the pressure inside the porous pebble…

2020 Monthly Notices of the Royal Astronomical Society
Rosetta 65
Standing on the Shoulders of Giants: New Mass and Distance Estimates for Betelgeuse through Combined Evolutionary, Asteroseismic, and Hydrodynamic Simulations with MESA
DOI: 10.3847/1538-4357/abb8db Bibcode: 2020ApJ...902...63J

Kobayashi, Chiaki; Nomoto, Ken'ichi; Ireland, Michael +3 more

We conduct a rigorous examination of the nearby red supergiant Betelgeuse by drawing on the synthesis of new observational data and three different modeling techniques. Our observational results include the release of new, processed photometric measurements collected with the space-based Solar Mass Ejection Imager instrument prior to Betelgeuse's …

2020 The Astrophysical Journal
Gaia Hipparcos 65