Search Publications
Direct Imaging Explorations for Companions around Mid-Late M Stars from the Subaru/IRD Strategic Program
Henning, Thomas; Nakagawa, Takao; Currie, Thayne +32 more
The Subaru telescope is currently performing a strategic program (SSP) using the high-precision near-infrared (NIR) spectrometer IRD to search for exoplanets around nearby mid/late M dwarfs via radial velocity (RV) monitoring. As part of the observing strategy for the exoplanet survey, signatures of massive companions such as RV trends are used to…
The First Photometric and Spectroscopic Studies of ASASSN-V J015428.67+204247.2 and its Relation to the Population of Low Mass Ratio Contact Binaries
Wang, Xi; Li, Kai; Gao, Xing +4 more
We performed photometric, spectroscopic and orbital period investigations of ASASSN-V J015428.67+204247.2 (hereafter, J015428) for the first time. The light curves of VRI bands were obtained. Through the analysis of Wilson-Devinney program, J015428 was found as an A-subtype medium contact binary system with a low-mass ratio (q = 0.129, f = 26.8%).…
A re-analysis of equilibrium chemistry in five hot Jupiters
Drossart, P.; Panek, E.; Beaulieu, J. -P. +4 more
Aims: Studies of chemistry and chemical composition are fundamental to exploring the formation histories of planets and planetary systems. We propose having another look at five targets to better determine their composition and the chemical mechanisms taking place in their atmospheres. We present a re-analysis of five hot Jupiters, combining …
The Pristine Inner Galaxy Survey (PIGS) - VI. Different vertical distributions between two DIBs at 442.8 nm and 862.1 nm
Fouesneau, Morgan; Sestito, Federico; Martin, Nicolas F. +8 more
Although diffuse interstellar bands (DIBs) were discovered over 100 yr ago, for most of them, their origins are still unknown. Investigation on the correlations between different DIBs is an important way to study the behaviour and distributions of their carriers. Based on stacking thousands of spectra from the Pristine Inner Galaxy Survey, we stud…
BVRI polarization of stars in the direction of Stock 19
Topasna, Gregory A.; Mateja, Frank M.; Kaltcheva, Nadejda T.
We present BVRI polarimetric measurements of nine bright stars in a 15'-square region centered on Stock 19. Seven of them satisfy the Serkowski equation for star light polarization due to interstellar dust. This allowed us to estimate the degree of maximum polarization (pmax) and the wavelength of maximum polarization (λmax).…
Multi-epoch variability of AT 2000ch (SN 2000ch) in NGC 3432. A radio continuum and optical study
Bomans, Dominik J.; Weis, Kerstin; Dettmar, Ralf-Jürgen +5 more
Context. AT 2000ch is a highly variable massive star and supernova imposter in NGC 3432 first detected in 2000. It is similar and often compared to SN 2009ip, and it is therefore expected to undergo a core-collapse supernova (SN) - a SN imposter of similar brightness - in the near future.
Aims: We characterize the long-term variability of AT …
Simplifying asteroseismic analysis of solar-like oscillators. An application of principal component analysis for dimensionality reduction
Chaplin, W. J.; Davies, G. R.; Nielsen, M. B. +5 more
Context. The asteroseismic analysis of stellar power density spectra is often computationally expensive. The models used in the analysis may require several dozen parameters to accurately describe features in the spectra caused by the oscillation modes and surface granulation. Many of these parameters are often highly correlated, making the parame…
The Solar Particle Acceleration Radiation and Kinetics (SPARK) Mission Concept
Massa, Paolo; Krucker, Säm; Piana, Michele +57 more
Particle acceleration is a fundamental process arising in many astrophysical objects, including active galactic nuclei, black holes, neutron stars, gamma-ray bursts, accretion disks, solar and stellar coronae, and planetary magnetospheres. Its ubiquity means energetic particles permeate the Universe and influence the conditions for the emergence a…
Azimuthal temperature variations in ISO-Oph 2 from multifrequency ALMA observations
Casassus, Simon; Christiaens, Valentin; Ribas, Álvaro +8 more
Environmental effects, such as stellar fly-bys and external irradiation, are thought to affect the evolution of protoplanetary discs in clustered star formation. Previous Atacama Large Millimetre/submillimetre Array (ALMA) images at 225 GHz of the ISO-Oph 2 binary revealed a peculiar morphology in the disc of the primary, perhaps due to a possible…
Calibrating SPI-ACS/INTEGRAL for gamma-ray bursts and re-estimating energetics of GRB/GW 190425 in gamma-ray range
Pozanenko, A. S.; Minaev, P. Yu
SPI-ACS/INTEGRAL is one of the most sensitive orbital gamma-ray detectors in energy range above 80 keV. Since 2002 it registered several thousands of gamma-ray bursts (GRBs), including the bursts associated with LIGO-Virgo gravitational wave events GW 170817 and GW 190425. No dedicated in-flight calibrations were performed for SPI-ACS/INTEGRAL, co…