Search Publications

The ALPINE-ALMA [CII] survey. The contribution of major mergers to the galaxy mass assembly at z ∼ 5
DOI: 10.1051/0004-6361/202141306 Bibcode: 2021A&A...653A.111R

Cimatti, A.; Rodighiero, G.; Schaerer, D. +25 more

Context. Galaxy mergers are thought to be one of the main mechanisms of the mass assembly of galaxies in the Universe, but there is still little direct observational evidence of how frequent they are at z ≳ 4. Recently, many works have suggested a possible increase in the fraction of major mergers in the early Universe, reviving the debate on whic…

2021 Astronomy and Astrophysics
eHST 48
The search for failed supernovae with the Large Binocular Telescope: N6946-BH1, still no star
DOI: 10.1093/mnras/stab2620 Bibcode: 2021MNRAS.508.1156B

Kochanek, C. S.; Stanek, K. Z.; Dai, X. +2 more

We present new Large Binocular Telescope, Hubble Space Telescope, and Spitzer Space Telescope data for the failed supernova candidate N6946-BH1. We also report an unsuccessful attempt to detect the candidate with Chandra. The ~300 000 $\, \mathrm{L}_\odot$ red supergiant progenitor underwent an outburst in 2009 and has since disappeared in the opt…

2021 Monthly Notices of the Royal Astronomical Society
eHST 48
An unusually low density ultra-short period super-Earth and three mini-Neptunes around the old star TOI-561
DOI: 10.1093/mnras/staa3728 Bibcode: 2021MNRAS.501.4148L

Scandariato, G.; Pagano, I.; Winn, J. N. +38 more

Based on HARPS-N radial velocities (RVs) and TESS photometry, we present a full characterization of the planetary system orbiting the late G dwarf TOI-561. After the identification of three transiting candidates by TESS, we discovered two additional external planets from RV analysis. RVs cannot confirm the outer TESS transiting candidate, which wo…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 48
Gaia Early Data Release 3. Modelling and calibration of Gaia's point and line spread functions
DOI: 10.1051/0004-6361/202039448 Bibcode: 2021A&A...649A..11R

Mora, A.; Evans, D. W.; Brown, A. G. A. +18 more

Context. The unprecedented astrometric precision of the Gaia mission relies on accurate estimates of the locations of sources in the Gaia data stream. This is ultimately performed by point spread function (PSF) fitting, which in turn requires an accurate reconstruction of the PSF, including calibrations of all the major dependences. These include …

2021 Astronomy and Astrophysics
Gaia 48
On the Observational Difference between the Accretion Disk-Corona Connections among Super- and Sub-Eddington Accreting Active Galactic Nuclei
DOI: 10.3847/1538-4357/abe37f Bibcode: 2021ApJ...910..103L

Brandt, W. N.; Luo, B.; Gallagher, S. C. +5 more

We present a systematic X-ray and multiwavelength study of a sample of 47 active galactic nuclei (AGNs) with reverberation mapping measurements. This sample includes 21 super-Eddington accreting AGNs and 26 sub-Eddington accreting AGNs. Using high-state observations with simultaneous X-ray and UV/optical measurements, we investigate whether super-…

2021 The Astrophysical Journal
XMM-Newton 48
Does the Magnetic Field Suppress Fragmentation in Massive Dense Cores?
DOI: 10.3847/1538-4357/abee1e Bibcode: 2021ApJ...912..159P

Ching, Tao-Chung; Qiu, Keping; Chen, Huei-Ru Vivien +15 more

Theoretical and numerical works indicate that a strong magnetic field should suppress fragmentation in dense cores. However, this has never been tested observationally in a relatively large sample of fragmenting massive dense cores. Here, we use the polarization data obtained in the Submillimeter Array Legacy Survey of Zhang et al. to build a samp…

2021 The Astrophysical Journal
Herschel 48
X-Ray Superflares from Pre-main-sequence Stars: Flare Energetics and Frequency
DOI: 10.3847/1538-4357/ac00be Bibcode: 2021ApJ...916...32G

Feigelson, Eric D.; Getman, Konstantin V.

Solar-type stars exhibit their highest levels of magnetic activity during their early convective pre-main-sequence (PMS) phase of evolution. The most powerful PMS flares, superflares and megaflares, have peak X-ray luminosities of $\mathrm{log}({L}_{{\rm{X}}})=30.5\mbox{-}34.0$ erg s-1 and total energies $\mathrm{log}({E}_{{\rm{X}}})=34…

2021 The Astrophysical Journal
Gaia 48
Galaxy Evolution in All Five CANDELS Fields and IllustrisTNG: Morphological, Structural, and the Major Merger Evolution to z 3
DOI: 10.3847/1538-4357/ac1422 Bibcode: 2021ApJ...919..139W

Conselice, C. J.; Duncan, K.; Whitney, A. +1 more

A fundamental feature of galaxies is their structure, yet we are just now understanding the evolution of structural properties in quantitative ways. As such, we explore the quantitative nonparametric structural evolution of 16,778 galaxies up to z ~ 3 in all five CANDELS fields, the largest collection of high-resolution images of distant galaxies …

2021 The Astrophysical Journal
eHST 48
Probing the nature of dark matter with accreted globular cluster streams
DOI: 10.1093/mnras/staa3597 Bibcode: 2021MNRAS.501..179M

Malhan, Khyati; Valluri, Monica; Freese, Katherine

The steepness of the central density profiles of dark matter (DM) in low-mass galaxy haloes (e.g. dwarf galaxies) is a powerful probe of the nature of DM. We propose a novel scheme to probe the inner profiles of galaxy subhaloes using stellar streams. We show that the present-day morphological and dynamical properties of accreted globular cluster …

2021 Monthly Notices of the Royal Astronomical Society
Gaia 48
A circular polarization survey for radio stars with the Australian SKA Pathfinder
DOI: 10.1093/mnras/stab299 Bibcode: 2021MNRAS.502.5438P

Kaplan, David L.; Lenc, Emil; Pritchard, Joshua +14 more

We present results from a circular polarization survey for radio stars in the Rapid ASKAP Continuum Survey (RACS). RACS is a survey of the entire sky south of δ = +41 being conducted with the Australian Square Kilometre Array Pathfinder telescope (ASKAP) over a 288 MHz wide band centred on 887.5 MHz. The data we analyse include Stokes …

2021 Monthly Notices of the Royal Astronomical Society
Gaia 48