Search Publications
The discovery of rest-frame UV colour gradients and a diversity of dust morphologies in bright z ≃ 7 Lyman-break galaxies
Bowler, R. A. A.; Cullen, F.; McLure, R. J. +2 more
We present deep ALMA dust continuum observations for a sample of luminous (MUV < -22) star-forming galaxies at z ≃ 7. We detect five of the six sources in the far-infrared (FIR), providing key constraints on the obscured star formation rate (SFR) and the infrared-excess-β (IRX-β) relation without the need for stacking. Despite the ga…
NGC 5846-UDG1: A Galaxy Formed Mostly by Star Formation in Massive, Extremely Dense Clumps of Gas
van Dokkum, Pieter; Romanowsky, Aaron J.; Conroy, Charlie +10 more
It has been shown that ultra-diffuse galaxies (UDGs) have higher specific frequencies of globular clusters, on average, than other dwarf galaxies with similar luminosities. The UDG NGC 5846-UDG1 is among the most extreme examples of globular cluster-rich galaxies found so far. Here we present new Hubble Space Telescope observations and analysis of…
Fast plasmoid-mediated reconnection in a solar flare
Feng, Xueshang; Song, Yongliang; Xue, Zhike +8 more
Magnetic reconnection is a multi-faceted process of energy conversion in astrophysical, space and laboratory plasmas that operates at microscopic scales but has macroscopic drivers and consequences. Solar flares present a key laboratory for its study, leaving imprints of the microscopic physics in radiation spectra and allowing the macroscopic evo…
Sizes of Lensed Lower-luminosity z = 4-8 Galaxies from the Hubble Frontier Field Program
Oesch, P. A.; Bouwens, R. J.; Illingworth, G. D. +3 more
We constrain the rest-UV size-luminosity relation for star-forming galaxies at z ~ 4 and z ~ 6, 7, and 8 identified behind clusters from the Hubble Frontier Fields (HFF) program. The size-luminosity relation is key to deriving accurate luminosity functions (LF) for faint galaxies. Making use of the latest lensing models and full data set for these…
Determination of X-ray pulsar geometry with IXPE polarimetry
Wu, Kinwah; Enoto, Teruaki; Turolla, Roberto +91 more
Using observations of X-ray pulsar Hercules X-1 by the Imaging X-ray Polarimetry Explorer we report a highly significant (>17σ) detection of the polarization signal from an accreting neutron star. The observed degree of linear polarization of ~10% is far below theoretical expectations for this object, and stays low throughout the spin cycle of …
Implications for galaxy formation models from observations of globular clusters around ultra-diffuse galaxies
Beasley, Michael A.; Trujillo, Ignacio; Peletier, Reynier F. +5 more
We present an analysis of Hubble Space Telescope observations of globular clusters (GCs) in six ultradiffuse galaxies (UDGs) in the Coma cluster, a sample that represents UDGs with large effective radii (Re), and use the results to evaluate competing formation models. We eliminate two significant sources of systematic uncertainty in the…
Planetary Nebulae: Sources of Enlightenment
Henry, R. B. C.; Kwitter, Karen B.
In this review/tutorial we explore planetary nebulae as a stage in the evolution of low-to-intermediate-mass stars, as major contributors to the mass and chemical enrichment of the interstellar medium, and as astrophysical laboratories. We discuss many observed properties of planetary nebulae, placing particular emphasis on element abundance deter…
The X-shooter Spectral Library (XSL): Data Release 3
Peletier, R. F.; Arentsen, A.; Coelho, P. R. T. +12 more
We present the third data release (DR3) of the X-shooter Spectral Library (XSL). This moderate-to-high resolution, near-ultraviolet-to-near-infrared (350-2480 nm, R ∼ 10 000) spectral library is composed of 830 stellar spectra of 683 stars. DR3 improves upon the previous data release by providing the combined de-reddened spectra of the three X-sho…
High Equivalent Width of Hα+[N II] Emission in z 8 Lyman-break Galaxies from IRAC 5.8 µm Observations: Evidence for Efficient Lyman-continuum Photon Production in the Epoch of Reionization
Illingworth, Garth D.; Labbé, Ivo; Bouwens, Rychard J. +3 more
We measure, for the first time, the median equivalent width (EW) of Hα+[N II] in star-forming galaxies at z ~ 8. Our estimate leverages the unique photometric depth of the Spitzer/IRAC 5.8 µm band mosaics (probing ≈5500-7100 Å at z ~ 8) of the GOODS Reionization Era Wide Area Treasury from Spitzer (GREATS) program. We median-stacked the stam…
MHD disc winds can reproduce fast disc dispersal and the correlation between accretion rate and disc mass in Lupus
Lodato, G.; van Dishoeck, E. F.; Tabone, B. +3 more
The final architecture of planetary systems depends on the extraction of angular momentum and mass-loss processes of the discs in which they form. Theoretical studies proposed that magnetohydrodynamic winds launched from the discs (MHD disc winds) could govern accretion and disc dispersal. In this work, we revisit the observed disc demographics in…