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Radio properties of the OH megamaser galaxy IIZw 096
Chen, Xi; Zhang, Bo; Wu, Hong +9 more
Based on the two-epoch European Very Long Baseline Interferometry (VLBI) Network (EVN) archive data from OH line observations of IIZw 096, we confirm that the high-resolution OH emission in this source mainly comes from two spots (OH1 and OH2) of component (comp) D1 of this merging system. We found no significant variations in the OH 1667 MHz line…
Taxonomy of protoplanetary discs observed with ALMA
Ward-Thompson, Derek; Kirk, Jason; Parker, Raeesa
Many observations of protoplanetary discs studied with ALMA have revealed the complex substructure present in the discs. Rings and gaps in the dust continuum are now a common sight in many discs; however, their origins still remain unknown. We look at all protoplanetary disc images taken with ALMA from cycles 0 to 5 and find that 56 discs show cle…
Twelve-Year Cycle in the Cloud Top Winds Derived from VMC/Venus Express and UVI/Akatsuki Imaging
Titov, Dmitrij V.; Ignatiev, Nikolay I.; Khatuntsev, Igor V. +3 more
We present joint analysis of the UV (365 nm) images captured by the cameras on board ESA's Venus Express and JAXA's Akatsuki spacecraft. These observations enabled almost continuous characterization of the cloud top circulation over the longest period of time so far (2006-2021). More than 46,000 wind vectors were derived from tracking the UV cloud…
A highly mutually inclined compact warm-Jupiter system KOI-984?
Schmitt, J. H. M. M.; Czesla, S.; Wang, X. +6 more
The discovery of a population of close-orbiting giant planets (≤ 1 au) has raised a number of questions about their origins and dynamical histories. These issues have still not been fully resolved, despite over 20 years of exoplanet detections and a large number of discovered exoplanets. In particular, it is unclear whether warm Jupiters (WJs) for…
3D mapping of the Wolf-Rayet nebula M 1-67: clues for post-common envelope evolution in massive stars
Guerrero, M. A.; Toalá, J. A.; Santamaría, E. +5 more
We present a 3D mapping of the Wolf-Rayet (WR) nebula M 1-67 around WR 124. We obtained high-resolution San Pedro Mártir (SPM) Manchester Echelle Spectrograph (MES) observations along 17 long-slit positions covering all morphological features in M 1-67. We are able to unveil the true morphology of M 1-67 and its kinematics by interpreting the SPM …
WDPhotTools - a white dwarf photometric toolkit in Python
Green, M. J.; Li, W.; Lam, M. C. +1 more
From data collection to photometric fitting and analysis of white dwarfs, to generating a white dwarf luminosity function requires numerous astrophysical, mathematical, and computational domain knowledge. The steep learning curve makes it difficult to enter the field, and often individuals have to reinvent the wheel to perform identical data reduc…
Two evolved close binary stars: GALEX J015054.4+310745 and the central star of the planetary nebula Hen 2-84
Reindl, Nicole; Irrgang, Andreas; Heber, Ulrich +3 more
As part of a survey to find close binary systems among central stars of planetary nebula, we present two newly discovered binary systems. GALEX J015054.4+310745 is identified as the central star of the possible planetary nebula Fr 2-22. We find it to be a single-lined spectroscopic binary with an orbital period of 0.2554435(10) d. We support the p…
A Study of 90 GHz Dust Emissivity on Molecular Cloud and Filament Scales
Hensley, Brandon; Friesen, Rachel; Sadavoy, Sarah +19 more
Recent observations from the MUSTANG2 instrument on the Green Bank Telescope have revealed evidence of enhanced long-wavelength emission in the dust spectral energy distribution (SED) in the Orion Molecular Cloud (OMC) 2/3 filament on 25″ (0.1 pc) scales. Here we present a measurement of the SED on larger spatial scales (map size 0.°5-3° or 3-20 p…
New constraints on the minimum mass for thermonuclear lithium burning in brown dwarfs
del Burgo, C.; Martín, E. L.; Lodieu, N.
The theory of substellar evolution predicts that there is a sharp mass boundary between lithium and non-lithium brown dwarfs, not far below the substellar-mass limit. The imprint of thermonuclear burning is carved on the surface lithium abundance of substellar-mass objects during the first few hundred million years of their evolution, leading to a…
Anomalous Orbital Characteristics of the AQ Col (EC 05217-3914) System
von Hippel, T.; Silvotti, R.; Kilkenny, D. +6 more
AQ Col (EC 05217-3914) is one of the first detected pulsating subdwarf B (sdB) stars and has been considered to be a single star. Photometric monitoring of AQ Col reveals a pulsation timing variation with a period of 486 days, interpreted as time delay due to reflex motion in a wide binary formed with an unseen companion with expected mass larger …