Search Publications
Missions
Journals
Publication Years
Brittle ice shell thickness of Enceladus from fracture distribution analysis
Cremonese, G.; Massironi, M.; Lucchetti, A. +2 more
We determine the depth of fracture penetration in multiple regions of Enceladus by performing self-similar clustering and length distribution analysis of fractures. The statistical characterization of fault-population attribute, such as length and clustering, provide a productive avenue for exploring deformation rate, stress transmission mode, rhe…
ALMA Multiple-transition Molecular Line Observations of the Ultraluminous Infrared Galaxy IRAS 20551-4250: Different HCN, HCO+, and HNC Excitation, and Implications for Infrared Radiative Pumping
Imanishi, Masatoshi; Izumi, Takuma; Nakanishi, Kouichiro
We present our ALMA multi-transition molecular line observational results for the ultraluminous infrared galaxy IRAS 20551-4250, which is known to contain a luminous buried active galactic nucleus and shows detectable vibrationally excited (v 2 = 1f) HCN and HNC emission lines. The rotational J = 1-0, 4-3, and 8-7 of HCN, {HCO}}+
General quadrupolar statistical anisotropy: Planck limits
Ramazanov, S.; Rubtsov, G.; Thorsrud, M. +1 more
Several early Universe scenarios predict a direction-dependent spectrum of primordial curvature perturbations. This translates into the violation of the statistical isotropy of cosmic microwave background radiation. Previous searches for statistical anisotropy mainly focussed on a quadrupolar direction-dependence characterised by a single multipol…
Predicting emission line fluxes and number counts of distant galaxies for cosmological surveys
Cimatti, A.; Daddi, E.; Rodighiero, G. +9 more
We estimate the number counts of line emitters at high redshift and their evolution with cosmic time based on a combination of photometry and spectroscopy. We predict the H α, H β, [O II], and [O III] line fluxes for more than 35 000 galaxies down to stellar masses of ∼109 M⊙ in the COSMOS and GOODS-S fields, applying standar…
Testing Metal-Poor Stellar Models and Isochrones with HST Parallaxes of Metal-Poor Stars
McArthur, B. E.; Benedict, G. F.; Sarajedini, A. +7 more
Hubble Space Telescope (HST) fine guidance sensor observations were used to obtain parallaxes of eight metal-poor ([Fe/H] < -1.4) stars. The parallaxes of these stars determined by the new Hipparcos reduction average 17% accuracy, in contrast to our new HST parallaxes, which average 1% accuracy and have errors on the individual parallaxes rangi…
DDO 216-A1: A Central Globular Cluster in a Low-luminosity Transition-type Galaxy
Dolphin, Andrew E.; Skillman, Evan D.; Williams, Benjamin F. +11 more
We confirm that the object DDO 216-A1 is a substantial globular cluster at the center of Local Group galaxy DDO 216 (the Pegasus dwarf irregular), using Hubble Space Telescope ACS imaging. By fitting isochrones, we find the cluster metallicity [M/H] = -1.6 ± 0.2, for reddening E(B-V) = 0.16 ± 0.02 the best-fit age is 12.3 ± 0.8 Gyr. There are ≈ 30…
Comets: looking ahead
A'Hearn, Michael F.
We outline the key questions about comets that must be answered in order to understand cometary formation in the context of the protoplanetary disc and the role of comets in the formation and evolution of the solar system. We then discuss the new understanding of comets from Rosetta and from other recent advances, including work presented by other…
Mechanical and electrostatic experiments with dust particles collected in the inner coma of comet 67P by COSIMA onboard Rosetta
Altobelli, Nicolas; Haerendel, Gerhard; Langevin, Yves +30 more
The in situ cometary dust particle instrument COSIMA (COmetary Secondary Ion Mass Analyser) onboard ESA's Rosetta mission has collected about 31 000 dust particles in the inner coma of comet 67P/Churyumov-Gerasimenko since August 2014. The particles are identified by optical microscope imaging and analysed by time-of-flight secondary ion mass spec…
Shocks and Tides Quantified in the “Sausage” Cluster, CIZA J2242.8+5301 Using N-body/Hydrodynamical Simulations
Broadhurst, T.; Molnar, S. M.
The colliding cluster, CIZA J2242.8+5301, displays a spectacular, almost 2 Mpc long shock front with a radio based Mach number M≃ 5, that is puzzlingly large compared to the X-ray estimate of M≃ 2.5. The extent to which the X-ray temperature jump is diluted by cooler unshocked gas projected through the cluster currently lacks quantification. Here …
Looking at A 0535+26 at low luminosities with NuSTAR
Hailey, Charles J.; Fürst, Felix; Kretschmar, Peter +12 more
We report on two NuSTAR observations of the high-mass X-ray binary