Search Publications
A black hole detected in the young massive LMC cluster NGC 1850
Dreizler, S.; Da Costa, G. S.; Cabrera-Ziri, I. +8 more
We report on the detection of a black hole (NGC 1850 BH1) in the ~100-Myr-old massive cluster NGC 1850 in the Large Magellanic Cloud. It is in a binary system with a main-sequence turn-off star (4.9 ± 0.4 M⊙), which is starting to fill its Roche lobe and is becoming distorted. Using 17 epochs of Very Large Telescope/Multi-Unit Spectrosc…
NGC 1850 BH1 is another stripped-star binary masquerading as a black hole
El-Badry, Kareem; Burdge, Kevin B.
We show that the radial velocity variable star in the black hole (BH) candidate NGC 1850 BH1 cannot be a normal ${\approx}5\hbox{-}{\rm M}_{\odot }$ subgiant, as was proposed, but is an overluminous stripped-envelope star with mass ≈1 M⊙. The result follows directly from the star's observed radius and the orbital period-density relation…
Exploring the physical properties of lensed star-forming clumps at 2 ≲ z ≲ 6
Zanella, A.; Castellano, M.; Grillo, C. +12 more
We study the physical properties (size, stellar mass, luminosity, and star formation rate) and scaling relations for a sample of 166 star-forming clumps with redshift z ~ 2-6.2. They are magnified by the Hubble Frontier Field galaxy cluster MACS J0416 and have robust lensing magnification (2 ≲ µ ≲ 82) computed by using our high-precision len…
Strong Lyman-α emission in an overdense region at z = 6.8: a very large (R 3 physical Mpc) ionized bubble in COSMOS?
Stark, Daniel P.; Endsley, Ryan
Our understanding of reionization has advanced considerably over the past decade, with several results now demonstrating that the intergalactic medium transitioned from substantially neutral at z = 7 to largely reionized at z = 6. However, little remains known about the sizes of ionized bubbles at z ≳ 7 as well as the galaxy overdensities which dr…
Astrometric identification of nearby binary stars - I. Predicted astrometric signals
Belokurov, Vasily; Evans, N. Wyn; Penoyre, Zephyr
We examine the capacity to identify binary systems from astrometric errors and deviations alone. Until the release of the fourth Gaia data release, we lack the full astrometric time-series that the satellite records, but as we show can still infer the presence of binaries from the best-fitting models, and their error, already available. We generat…
The pattern speed of the Milky Way bar/bulge from VIRAC and Gaia
Gerhard, Ortwin; Clarke, Jonathan P.
We compare distance resolved, absolute proper motions in the Milky Way bar/bulge region to a grid of made-to-measure dynamical models with well-defined pattern speeds. The data are obtained by combining the relative VVV InfraRed Astrometric Catalogue (VIRAC) v1 proper motions with the Gaia Data Release 2 absolute reference frame. We undertake a co…
Astrometric identification of nearby binary stars - II. Astrometric binaries in the Gaia Catalogue of Nearby Stars
Belokurov, Vasily; Evans, N. Wyn; Penoyre, Zephyr
We examine the capacity to identify binary systems from astrometric deviations alone. We apply our analysis to the Gaia eDR3 and DR2 data, specifically the Gaia Catalogue of Nearby Stars. We show we must renormalize (R)UWE over the local volume to avoid biasing local observations, giving a local unit weight error (LUWE). We use the simple criterio…
No strong dependence of Lyman continuum leakage on physical properties of star-forming galaxies at ≲ z ≲ 3.5
Schaerer, D.; Bolzonella, M.; Castellano, M. +15 more
We present Lyman continuum (LyC) radiation escape fraction (fesc) measurements for 183 spectroscopically confirmed star-forming galaxies in the redshift range 3.11 < z < 3.53 in the Chandra Deep Field South. We use ground-based imaging to measure fesc, and use ground- and space-based photometry to derive galaxy physical…
An extreme blue nugget, UV-bright starburst at z = 3.613 with 90 per cent of Lyman continuum photon escape
Chisholm, J.; Pérez-Fournon, I.; Schaerer, D. +9 more
We present the discovery and analysis of J1316+2614 at z = 3.6130, a UV-bright star-forming galaxy (MUV ≃ -24.7) with large escape of Lyman continuum (LyC) radiation. J1316+2614 is a young (≃10 Myr) star-forming galaxy with SFR ≃ 500 M⊙ yr-1 and a starburst mass of log(M⋆/M⊙) ≃ 9.7. It shows a…
Data Release 2 of S-PLUS: Accurate template-fitting based photometry covering 1000 deg2 in 12 optical filters
Molino, A.; Werle, A.; Mendes de Oliveira, C. +32 more
The Southern Photometric Local Universe Survey (S-PLUS) is an ongoing survey of ~9300 deg2 in the southern sky in a 12-band photometric system. This paper presents the second data release (DR2) of S-PLUS, consisting of 514 tiles covering an area of 950 deg2. The data has been fully calibrated using a new photometric calibrati…