Search Publications
Planck satellite constraints on pseudo-Nambu-Goldstone boson quintessence
Liddle, Andrew R.; Smer-Barreto, Vanessa
The pseudo-Nambu-Goldstone Boson (PNGB) potential, defined through the amplitude M4 and width f of its characteristic potential V(phi) = M4[1 + cos(phi/f)], is one of the best-suited models for the study of thawing quintessence. We analyse its present observational constraints by direct numerical solution of the scalar field …
Galactic cold cores. VIII. Filament formation and evolution: Filament properties in context with evolutionary models
Bernard, J. -P.; Juvela, M.; Marshall, D. J. +15 more
Context. The onset of star formation is intimately linked with the presence of massive unstable filamentary structures. These filaments are therefore key for theoretical models that aim to reproduce the observed characteristics of the star formation process in the Galaxy.
Aims: As part of the filament study carried out by the Herschel Galacti…
A systematic X-ray study of the dwarf novae observed with Suzaku
Tsujimoto, Masahiro; Hayashi, Takayuki; Wada, Qazuya +1 more
X-ray behavior of the dwarf novae (DNe) outside the quiescent state has not been fully understood. We thus assembled 21 data sets of the 15 DNe observed by the Suzaku satellite by the end of 2013, which include spectra taken during not only the quiescence, but also the transitional, outburst, and super-outburst states. Starting with the traditiona…
Outflows of hot molecular gas in ultra-luminous infrared galaxies mapped with VLT-SINFONI
Colina, L.; Arribas, S.; Pereira-Santaella, M. +5 more
We present the detection and morphological characterization of hot molecular gas outflows in nearby ultra-luminous infrared galaxies (ULIRGs), using the Spectrograph for Integral Field Observations in the Near Infrared (SINFONI) on the Very Large Telescope (VLT). We detect outflows observed in the 2.12 µm H2 1-0 S(1) line for thre…
Searching for γ-ray signature in WHSP blazars. Fermi-LAT detection of 150 excess signal in the 0.3-500 GeV band
Chang, Y. -L.; Arsioli, B.
Aims: A direct search of γ-ray emission centered on multifrequency selected candidates is a valuable complementary approach to the standard search adopted in current γ-ray Fermi-LAT catalogs. Our sources are part of the 2WHSP sample that was assembled with the aim of providing targets for Imaging Atmospheric Cherenkov Telescopes (IACT). A lik…
X-Ray Emission from the Nuclear Region of Arp 220
Elvis, Martin; Risaliti, Guido; Karovska, Margarita +6 more
We present an imaging and spectral analysis of the nuclear region of the ultraluminous infrared galaxy merger of Arp 220, using deep Chandra-ACIS observations summing up to ∼ 300 {{ks}}. Narrowband imaging with subpixel resolution of the innermost nuclear region reveals two distinct Fe-K emitting sources, coincident with the infrared and radio nuc…
Effects of electrically charged dark matter on cosmic microwave background anisotropies
Yoshida, Naoki; Kohri, Kazunori; Kamada, Ayuki +1 more
We examine the possibility that dark matter consists of charged massive particles (CHAMPs) in view of the cosmic microwave background (CMB) anisotropies. The evolution of cosmological perturbations of CHAMPs with other components is followed in a self-consistent manner, without assuming that CHAMPs and baryons are tightly coupled. We incorporate f…
Proper motion survey and kinematic analysis of the ρ Ophiuchi embedded cluster
Bouy, H.; Ducourant, C.; Bontemps, S. +7 more
Context. The ρ Ophiuchi molecular complex and in particular the Lynds L1688 dark cloud is unique in its proximity (~130 pc), in its richness in young stars and protostars, and in its youth (0.5 Myr). It is certainly one of the best targets currently accessible from the ground to study the early phases of star-formation. Proper motion analysis is a…
The effect of asymmetric surface topography on dust dynamics on airless bodies
Horányi, M.; Piquette, M.
Without a significant atmosphere or global magnetic field, the lunar surface is exposed to micrometeoroid bombardment, ultraviolet (UV) radiation, and the solar wind. Micrometeoroid bombardment grinds the surface into a regolith comprised of dust grains ranging in size from 10 nm to 1 mm (Grün et al., 2011). Incident UV radiation and solar wind el…
Sunspots, Starspots, and Elemental Abundances
Doschek, G. A.; Warren, H. P.
Element abundances in the solar photosphere, chromosphere, transition region, and corona are key parameters for investigating sources of the solar wind and for estimating radiative losses in the quiet corona and in dynamical events such as solar flares. Abundances in the solar corona and photosphere differ from each other depending on the first io…