Search Publications
Mapping the hot gas temperature in galaxy clusters using X-ray and Sunyaev-Zel'dovich imaging
Adam, R.; Arnaud, M.; Benoît, A. +42 more
We propose a method to map the temperature distribution of the hot gas in galaxy clusters that uses resolved images of the thermal Sunyaev-Zel'dovich (tSZ) effect in combination with X-ray data. Application to images from the New IRAM KIDs Array (NIKA) and XMM-Newton allows us to measure and determine the spatial distribution of the gas temperatur…
Radio jets in NGC 4151: where eMERLIN meets HST
Muxlow, T. W. B.; Argo, M. K.; Knapen, J. H. +11 more
We present high-sensitivity eMERLIN radio images of the Seyfert galaxy NGC 4151 at 1.51 GHz. We compare the new eMERLIN images to those from archival MERLIN observations in 1993 to determine the change in jet morphology in the 22 yr between observations. We report an increase by almost a factor of 2 in the peak flux density of the central core com…
H2 in low-ionization structures of planetary nebulae
Gonçalves, Denise R.; Akras, Stavros; Ramos-Larios, Gerardo
We report the detection of near-IR H2 emission from the low-ionization structures (knots) in two planetary nebulae. The deepest ever high-angular-resolution H2 (1-0) S(1) at 2.122 µm, H2 (2-1) S(1) at 2.248 µm and Brγ images of K 4-47 and NGC 7662, obtained using the Near InfraRed Imager and Spectromete…
Seasonal changes of the volatile density in the coma and on the surface of comet 67P/Churyumov-Gerasimenko
Altwegg, Kathrin; Rubin, Martin; Läuter, Matthias +1 more
Starting from several monthly data sets of Rosetta's COmetary Pressure Sensor, we reconstruct the gas density in the coma around comet 67P/Churyumov-Gerasimenko. The underlying inverse gas model is constructed by fitting ten thousands of measurements to thousands of potential gas sources distributed across the entire nucleus surface. The ensuing s…
The Formation and Physical Origin of Highly Ionized Cooling Gas
Heckman, Timothy M.; Bordoloi, Rongmon; Wagner, Alexander Y. +1 more
We present a simple model that explains the origin of warm, diffuse gas seen primarily as highly ionized absorption-line systems in the spectra of background sources. We predict the observed column densities of several highly ionized transitions such as O VI, O vii, Ne viii, N v, and Mg x, and we present a unified comparison of the model predictio…
Gaia Assorted Mass Binaries Long Excluded from SLoWPoKES (GAMBLES): Identifying Ultra-wide Binary Pairs with Components of Diverse Mass
Stassun, Keivan G.; Oelkers, Ryan J.; Dhital, Saurav
The formation and evolution of binary star systems are some of the remaining key questions in modern astronomy. Wide binary pairs (separations >103 au) are particularly intriguing because their low binding energies make it difficult for the stars to stay gravitationally bound over extended timescales, and thus to probe the dynamics o…
Hints for Small Disks around Very Low Mass Stars and Brown Dwarfs
Pascucci, Ilaria; Henning, Thomas; Ménard, François +6 more
The properties of disks around brown dwarfs and very low mass stars (hereafter VLMOs) provide important boundary conditions on the process of planet formation and inform us about the numbers and masses of planets than can form in this regime. We use the Herschel Space Observatory PACS spectrometer to measure the continuum and [O I] 63 µm lin…
Detection of Interstellar Ortho-D2H+ with SOFIA
Caselli, Paola; Menten, Karl M.; Okada, Yoko +9 more
We report on the detection of the ground-state rotational line of ortho-D2H+ at 1.477 THz (203 µm) using the German REceiver for Astronomy at Terahertz frequencies (GREAT) on board the Stratospheric Observatory For Infrared Astronomy (SOFIA). The line is seen in absorption against far-infrared continuum from the protost…
The Star Blended with the MOA-2008-BLG-310 Source Is Not the Exoplanet Host Star
Bennett, D. P.; Anderson, J.; Gould, A. +7 more
High-resolution Hubble Space Telescope (HST) image analysis of the MOA-2008-BLG-310 microlens system indicates that the excess flux at the location of the source found in the discovery paper cannot primarily be due to the lens star because it does not match the lens-source relative proper motion, {µ }{rel}, predicted by the microl…
Modelling and simulation of large-scale polarized dust emission over the southern Galactic cap using the GASS HI data
Boulanger, F.; Aumont, J.; Bock, J. J. +8 more
The Planck survey has quantified polarized Galactic foregrounds and established that they are a main limiting factor in the quest for the cosmic microwave background B-mode signal induced by primordial gravitational waves during cosmic inflation. Accurate separation of the Galactic foregrounds therefore binds this quest to our understanding of the…