Search Publications

Far-infrared CO and H₂O emission in intermediate-mass protostars

Karska, A.; Fuente, A.; Kristensen, L. E. +4 more

Context. Intermediate-mass young stellar objects (YSOs) provide a link to understanding how feedback from shocks and UV radiation scales from low- to high-mass star forming regions.
Aims: Our aim is to analyze excitation of CO and H₂O in deeply embedded intermediate-mass YSOs and compare it with similar studies on low-mass and high…

Modelling of the surface emission of the low magnetic field magnetar SGR 0418+5729

Rea, N.; Perna, R.; Guillot, S. +2 more

We perform a detailed modelling of the post-outburst surface emission of the low magnetic field magnetar SGR 0418+5729. The dipolar magnetic field of this source, B=6 {× 10^{12}}{ G} estimated from its spin-down rate, is in the observed range of magnetic fields for normal pulsars. The source is further characterized by a high pulse fraction and a …

The velocity distribution in the solar neighbourhood from the LAMOST pilot survey

Zhang, Yong; Xu, Yan; Mao, Shude +5 more

We use about 15 000 F/G nearby dwarf stars selected from the LAMOST pilot survey to map the U-V velocity distribution in the solar neighbourhood. An extreme deconvolution algorithm is applied to reconstruct an empirical multi-Gaussian model. In addition to the well-known substructures, e.g. Sirius, Coma Berenices, Hyades-Pleiades overdensities, se…

Satellite content and quenching of star formation in galaxy groups at z ~ 1.8

Finoguenov, A.; Daddi, E.; Le Floc'h, E. +13 more

We study the properties of satellites in the environment of massive star-forming galaxies at z ~ 1.8 in the COSMOS field, using a sample of 215 galaxies on the main sequence of star formation with an average mass of ~10¹¹M_⊙. At z> 1.5, these galaxies typically trace halos of mass ≳10¹³M_⊙. We use optic…

Inflection point inflation and dark energy in supergravity

Guo, Zong-Kuan; Gao, Tie-Jun

We consider an inflection point inflationary model in supergravity with a single chiral superfield and show that the predicted values of the scalar spectral index and tensor-to-scalar ratio are consistent with the Planck 2015 results. In this model supersymmetry is strongly broken after inflation, which results in a non-supersymmetry de Sitter vac…

To what extent can intracrater layered deposits that lack clear sedimentary textures be used to infer depositional environments?

Kah, Linda C.; Cadieux, Sarah B.

Craters within Arabia Terra, Mars, contain hundreds of meters of layered strata showing systematic alternation between slope- and cliff-forming units, suggesting either rhythmic deposition of distinct lithologies or similar lithologies that experienced differential cementation. On Earth, rhythmically deposited strata can be examined in terms of st…

Spectral models for early time SN 2011fe observations

Gal-Yam, A.; Wang, L.; Sullivan, M. +12 more

We use observed UV through near-IR spectra to examine whether SN 2011fe can be understood in the framework of Branch-normal Type Ia supernovae (SNe Ia) and to examine its individual peculiarities. As a benchmark, we use a delayed-detonation model with a progenitor metallicity of Z_⊙/20. We study the sensitivity of features to variations …

Solar cycle variations in the powers and damping rates of low-degree solar acoustic oscillations

Nakariakov, V. M.; Broomhall, A. -M.; Pugh, C. E.

Helioseismology uses the Sun's natural resonant oscillations to study the solar interior. The properties of the solar oscillations are sensitive to the Sun'2019;s magnetic activity cycle. Here we examine variations in the powers, damping rates, and energy supply rates of the most prominent acoustic oscillations in unresolved, Sun-as-a-star data, o…

The Megasecond Chandra X-Ray Visionary Project Observation of NGC 3115. III. Luminosity Functions of LMXBs and Dependence on Stellar Environments

Romanowsky, Aaron J.; Brodie, Jean P.; Remillard, Ronald A. +7 more

We studied the X-ray luminosity function (XLF) of low-mass X-ray binaries (LMXBs) in the nearby lenticular galaxy NGC 3115, using the Megasecond Chandra X-ray Visionary Project Observation. With a total exposure time of ∼1.1 Ms, we constructed the XLF down to a limiting luminosity of ∼10³⁶ erg s^-1, which is much deeper than t…

Elemental Abundance Analyses with DAO Spectrograms. XXXVI. The Hot Metallic Line Stars Theta Leonis and Omicron Pegasi

Adelman, Saul J.; Gulliver, Austin F.; Heaton, Robert J.