Search Publications
Pits Formation from Volatile Outgassing on 67P/Churyumov-Gerasimenko
Jorda, L.; Lamy, P.; Sierks, H. +8 more
We investigate the thermal evolution of comet 67P/Churyumov-Gerasimenko’s subsurface in the Seth_01 region, where active pits have been observed by the ESA/Rosetta mission. Our simulations show that clathrate destabilization and amorphous ice crystallization can occur at depths corresponding to those of the observed pits in a timescale shorter tha…
Searching for features of a string-inspired inflationary model with cosmological observations
Hu, Bin; Cai, Yi-Fu; Ferreira, Elisa G. M. +1 more
The latest Planck results show a power deficit in the temperature anisotropies near ℓ≈20 in the cosmic microwave background (CMB). This observation can hardly be explained within the standard inflationary Λ -cold-dark-matter (Λ CDM ) scenario. In this paper we consider a string theory inspired inflationary model (axion monodromy inflation) with a …
Visual and ultraviolet flux variability of the bright CP star θ Aurigae
Krtička, J.; Lüftinger, T.; Mikulášek, Z. +1 more
Context. Chemically peculiar stars of the upper part of the main sequence show periodical variability in line intensities and continua, modulated by the stellar rotation, which is attributed to the existence of chemical spots on the surface of these stars. The flux variability is caused by the changing redistribution rate of the radiative flux pre…
Hubble Space Telescope Emission-line Galaxies at z ~ 2: The Mystery of Neon
Trump, Jonathan R.; Schneider, Donald P.; Gronwall, Caryl +6 more
We use near-infrared grism spectroscopy from the Hubble Space Telescope to examine the strength of [Ne III] λ3869 relative to Hβ, [O II] λ3727, and [O III] λ5007 in 236 low-mass (7.5 <~ log (M */M ⊙) <~ 10.5) star-forming galaxies in the redshift range 1.90 < z < 2.35. By stacking the data by stellar mass, we show…
The 2D Distribution of Iron-rich Ejecta in the Remnant of SN 1885 in M31
Fesen, Robert A.; Hamilton, Andrew J. S.; Höflich, Peter A.
We present Hubble Space Telescope (HST) ultraviolet Fe i and Fe ii images of the remnant of Supernova 1885 (S And) which is observed in absorption against the bulge of the Andromeda galaxy, M31. We compare these Fe i and Fe ii absorption line images to previous HST absorption images of S And, of which the highest quality and theoretically cleanest…
X-ray spectral and variability properties of low-mass active galactic nuclei
Fabian, A. C.; Miniutti, G.; Cackett, E. M. +3 more
We study the X-ray properties of a sample of 14 optically selected low-mass active galactic nuclei (AGN) whose masses lie within the range 105-2 × 106 M⊙ with XMM-Newton. Only six of these low-mass AGN have previously been studied with sufficient quality X-ray data, thus, we have more than double the number of low-…
The surface magnetic field and chemical abundance distributions of the B2V helium-strong star HD 184927
Marcolino, W.; Kochukhov, O.; Bohlender, D. +8 more
A new time series of high-resolution Stokes I and V spectra of the magnetic B2V star HD 184927 has been obtained in the context of the Magnetism in Massive Stars Large Program with an Echelle SpectroPolarimetric Device for the Observation of Stars (ESPaDOnS) spectropolarimeter at the Canada-France-Hawaii Telescope and dimaPol liquid crystal spectr…
Why Does the Apparent Mass of a Coronal Mass Ejection Increase?
Feng, Li; Lu, Lei; Gan, Weiqun +4 more
Mass is one of the most fundamental parameters characterizing the dynamics of a coronal mass ejection (CME). It has been found that CME apparent mass measured from the brightness enhancement in coronagraphs increases during its evolution in the corona. However, the physics behind it is not clear. Does the apparent mass gain come from the outflow f…
The Subaru-XMM-Newton Deep Survey (SXDS). VIII. Multi-wavelength identification, optical/NIR spectroscopic properties, and photometric redshifts of X-ray sources†
Ouchi, Masami; Simpson, Chris; Curtis-Lake, Emma +27 more
We report on the multi-wavelength identification of the X-ray sources found in the Subaru-XMM-Newton Deep Survey (SXDS) using deep imaging data covering the wavelength range between the far-UV and mid-IR (MIR). We select a primary counterpart of each X-ray source by applying the likelihood ratio method to R-band, 3.6 µm, near-UV, and 24 &mic…
The photospheric Poynting flux and coronal heating
Welsch, Brian T.
Some models of coronal heating suppose that convective motions at the photosphere shuffle the footpoints of coronal magnetic fields and thereby inject sufficient magnetic energy upward to account for observed coronal and chromospheric energy losses in active regions. Using high-resolution observations of plage magnetic fields made with the Solar O…