Search Publications
The case for thermalization as a contributor to the [C II] deficit
Hunt, Leslie K.; Calzetti, Daniela; De Looze, Ilse +15 more
The [C II] deficit, which describes the observed decrease in the ratio of [C II] 158 µm emission to continuum infrared emission in galaxies with high star formation surface densities, places a significant challenge to the interpretation of [C II] detections from across the observable universe. In an attempt to further decode the cause of the…
Suppressed cooling and turbulent heating in the core of X-ray luminous clusters RXCJ1504.1-0248 and Abell 1664
McNamara, Brian R.; Fabian, Andrew C.; Sanders, Jeremy S. +3 more
We present the analysis of XMM-Newton observations of two X-ray luminous cool core clusters, RXCJ1504.1-0248 and Abell 1664. The Reflection Grating Spectrometer reveals a radiative cooling rate of $180\pm 40\, \rm M_{\odot }\rm \, yr^{-1}$ and $34\pm 6\, \rm M_{\odot }\rm \, yr^{-1}$ in RXCJ1504.1-0248 and Abell 1664 for gas above 0.7 keV, respect…
Testing the tidal stripping scenario of ultracompact dwarf galaxy formation by using internal properties
Drinkwater, Michael J.; Liu, Chengze; Côté, Patrick +5 more
We use the hydrodynamical EAGLE simulation to test if ultracompact dwarf galaxies (UCDs) can form by tidal stripping by predicting the ages and metallicities of tidally stripped galaxy nuclei in massive galaxy clusters, and compare these results to compiled observations of age and metallicities of observed UCDs. We further calculate the colours of…
Accretion and outflow activity in proto-brown dwarfs
Riaz, B.; Bally, J.
We present a near-infrared study of accretion and outflow activity in six Class 0/I proto-brown dwarfs (proto-BDs) using VLT/SINFONI spectroscopy and spectroimaging observations. The spectra show emission in several [Fe II] and H2 lines associated with jet/outflow activity, and in the accretion diagnostics of Pa β and Br γ lines. The pe…
High-contrast observations of brown dwarf companion HR 2562 B with the vector Apodizing Phase Plate coronagraph
Kenworthy, Matthew A.; Charbonneau, David; Close, Laird M. +8 more
The vector Apodizing Phase Plate (vAPP) is a class of pupil plane coronagraph that enables high-contrast imaging by modifying the Point Spread Function (PSF) to create a dark hole of deep flux suppression adjacent to the PSF core. Here, we recover the known brown dwarf HR 2562 B using a vAPP coronagraph, in conjunction with the Magellan Adaptive O…
A detailed study of X-ray cavities in the intracluster environment of the cool core cluster Abell 3017
Raychaudhury, Somak; Pandge, M. B.; Sebastian, Biny +1 more
We present a detailed analysis of a cool-core galaxy cluster Abell 3017, at a redshift of z = 0.219, which has been identified to be merging with its companion cluster Abell 3016. This study has made use of X-ray (Chandra), ultraviolet (UV) [Galaxy Evolution Explorer(GALEX)], optical [European Southern Observatory (ESO)/very large telescope (VLT)]…
Charge-exchange soft X-ray emission of highly charged ions with inclusion of multiple-electron capture
Cui, W.; Zhao, G.; Wu, Y. +7 more
Charge exchange has been recognized as a primary source of soft X-ray emission in many astrophysical outflow environments, including cometary and planetary exospheres impacted by the solar wind. Some models have been set up by using different data collections of charge-exchange cross-sections. However, multiple-electron transfer has not been inclu…
High-resolution X-ray spectroscopy of supergiant HMXB 4U 1700-37 during the compact object eclipse
Grinberg, V.; Hainich, R.; Torrejón, J. M. +6 more
We present an analysis of the first observation of the iconic high-mass X-ray binary 4U 1700-37 with the Chandra High-Energy Transmission Gratings (HETGs) during an X-ray eclipse. The goal of the observation was to study the structure/physical conditions in the clumpy stellar wind through high-resolution spectroscopy. We find the following: (a) Em…
The link between gas and stars in the S254-S258 star-forming region
Juvela, M.; Kirsanova, M. S.; Sobolev, A. M. +5 more
The paper aims to study relation between the distributions of the young stellar objects (YSOs) of different ages and the gas-dust constituents of the S254-S258 star formation complex. This is necessary to study the time evolution of the YSO distribution with respect to the gas and dust compounds that are responsible for the birth of the young star…
Observational constraints to the dynamics of dust particles in the coma of comet 67P/Churyumov-Gerasimenko
Sierks, H.; Fulle, M.; Güttler, C. +18 more
In this work, we aim to characterize the dust motion in the inner coma of comet 67P/Churyumov-Gerasimenko to provide constraints for theoretical 3D coma models. The OSIRIS camera on-board the Rosetta mission was able for the first time to acquire images of single dust particles from inside the cometary coma, very close to the nucleus. We analyse a…