Search Publications
Universal detection of high-temperature emission in X-ray isolated neutron stars
Yoneyama, Tomokage; Hayashida, Kiyoshi; Nakajima, Hiroshi +1 more
Strongly magnetized isolated neutron stars (NSs) are categorized into two families, according mainly to their magnetic field strength. Those with a higher magnetic field of 1014-1015 G are called magnetars, characterized by repeated short bursts, and the others are X-ray isolated neutron stars (XINSs) with 1013 G. …
X-Ray and Gamma-Ray Emission from Core-collapse Supernovae: Comparison of Three-dimensional Neutrino-driven Explosions with SN 1987A
Fransson, Claes; Janka, Hans-Thomas; Alp, Dennis +7 more
During the first few hundred days after the explosion, core-collapse supernovae (SNe) emit down-scattered X-rays and gamma-rays originating from radioactive line emissions, primarily from the 56Ni → 56Co → 56Fe chain. We use supernova (SN) models based on three-dimensional neutrino-driven explosion simulations of s…
Identification of organic molecules with a laboratory prototype based on the Laser Ablation-CosmOrbitrap
Engrand, C.; Vuitton, V.; Briois, C. +18 more
In the Solar System, extra-terrestrial organic molecules have been found on cometary primitive objects, on Titan and Enceladus icy moons and on Mars. Identification could be achieved for simple organic species by remote sensing based on spectroscopic methods. However in situ mass spectrometry is a key technology to determine the nature of more com…
The subgiant HR 7322 as an asteroseismic benchmark star
Huber, Daniel; Stokholm, Amalie; White, Timothy R. +5 more
We present an in-depth analysis of the bright subgiant HR 7322 (KIC 10005473) using Kepler short-cadence photometry, optical interferometry from CHARA, high-resolution spectra from SONG, and stellar modelling using GARSTEC grids, and the Bayesian grid-fitting algorithm BASTA. HR 7322 is only the second subgiant with high-quality Kepler asteroseism…
Pluto's ephemeris from ground-based stellar occultations (1988-2016)
Sicardy, B.; Gomes-Júnior, A. R.; Ortiz, J. L. +13 more
Context. From 1988 to 2016, several stellar occultations have been observed to characterise Pluto's atmosphere and its evolution. From each stellar occultation, an accurate astrometric position of Pluto at the observation epoch is derived. These positions mainly depend on the position of the occulted star and the precision of the timing.
Aims…
Testing the warmness of dark matter
Nunes, Rafael C.; Kumar, Suresh; Yadav, Santosh Kumar
Dark matter (DM) as a pressureless perfect fluid provides a good fit of the standard Λ cold dark matter (ΛCDM) model to the astrophysical and cosmological data. In this paper, we investigate two extended properties of DM: a possible time dependence of the equation of state of DM via Chevallier-Polarski-Linder parametrization, wdm = w
Searching for fast extragalactic X-ray transients in Chandra surveys
Bauer, F. E.; Brandt, W. N.; Xue, Y. Q. +4 more
Recent works have discovered two fast (≈10 ks) extragalactic X-ray transients in the Chandra Deep Field-South (CDF-S XT1 and XT2). These findings suggest that a large population of similar extragalactic transients might exist in archival X-ray observations. We develop a method that can effectively detect such transients in a single Chandra exposur…
The XUV irradiation and likely atmospheric escape of the super-Earth π Men c
Wheatley, Peter J.; Bourrier, Vincent; Ehrenreich, David +1 more
π Men c was recently announced as the first confirmed exoplanet from the TESS mission. The planet has a radius of just 2 R⊕ and it transits a nearby Sun-like star of naked-eye brightness, making it the ideal target for atmospheric characterization of a super-Earth. Here we analyse archival ROSAT and Swift observations of π Men in order …
OGLE-2017-BLG-1186: first application of asteroseismology and Gaussian processes to microlensing
Kim, S. -L.; Lee, C. -U.; Bennett, D. P. +102 more
We present the analysis of the event OGLE-2017-BLG-1186 from the 2017 Spitzer microlensing campaign. This is a remarkable microlensing event because its source is photometrically bright and variable, which makes it possible to perform an asteroseismic analysis using ground-based data. We find that the source star is an oscillating red giant with a…
Physical Properties of Galactic RV Tauri Stars from Gaia DR2 Data
Kiss, L. L.; Bódi, A.
We present the first period-luminosity and period-radius relation of Galactic RV Tauri variable stars. We have surveyed the literature for all variable stars belonging to this class and compiled the full set of their photometric and spectroscopic measurements. We crossmatched the final list of stars with the Gaia Data Release 2 database and took t…