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Optical and near-infrared data and modelling of nova V5668 Sgr
Lawrence, S. S.; Sokolovsky, K. V.; Diaz, M. +4 more
We present Hubble Space Telescope optical images, Keck-OSIRIS near-infrared (NIR) integral field spectroscopy data cubes and Keck-Near InfraRed Camera-2 (NIRC2) NIR images of nova V5668 Sgr from 2016 to 2019. The observations indicate enhanced emission at the polar caps and equatorial torus for low-ionization lines, and enhanced high-ionization em…
Isolated Massive Star Formation in G28.20-0.05
Law, Chi-Yan; Garay, Guido; Mardones, Diego +9 more
We report high-resolution 1.3 mm continuum and molecular line observations of the massive protostar G28.20-0.05 with Atacama Large Millimeter/submillimeter Array. The continuum image reveals a ring-like structure with 2000 au radius, similar to morphology seen in archival 1.3 cm Very Large Array observations. Based on its spectral index and associ…
A New Absolute Proper Motion Determination of Leo I Using HST/WFPC2 Images and Gaia EDR3
Horch, Elliott P.; Kozhurina-Platais, Vera; Casetti-Dinescu, Dana I. +3 more
We measure the absolute proper motion of Leo I using a WFPC2/HST data set that spans up to 10 yr to date the longest time baseline utilized for this satellite. The measurement relies on ~2300 Leo I stars located near the center of light of the galaxy; the correction to absolute proper motion is based on 174 Gaia EDR3 stars and 10 galaxies. Having …
Sublimation origin of active asteroid P/2018 P3
Mutchler, Max; Jewitt, David; Agarwal, Jessica +4 more
Context. Active asteroids show (typically transient) cometary activity, driven by a range of processes. A sub-set, sometimes called main-belt comets, may be driven by sublimation and so could be useful for tracing the present-day distribution of asteroid ice. Object P/2018 P3 has a Tisserand parameter 3.096 but a high eccentricity 0.415, placing i…
KIC 2857323: A Double-mode High-amplitude δ Scuti Star with Amplitude Decline of the First Overtone Mode
Esamdin, Ali; Yang, Tao-Zhi; Zuo, Zhao-Yu +2 more
We investigate the pulsating behavior of KIC 2857323 using high-precision observations from the Kepler mission. Fourier analysis of 4 yr time-series data reveals five independent frequencies for the light variation. Among them, two strong frequencies f 1 and f 3 with a period ratio of 0.774 identify this star as a double-mode…
The Galactic Distribution of Phosphorus: A Survey of 163 Disk and Halo Stars
Janowiecki, Steven; Cargile, Phillip; Hawkins, Keith +3 more
Phosphorus (P) is a critical element for life on Earth, yet the cosmic production sites of P are relatively uncertain. To understand how P has evolved in the solar neighborhood, we measured abundances for 163 FGK stars over a range of -1.09 < [Fe/H] < 0.47 using observations from the Habitable-zone Planet Finder instrument on the Hobby-Eberl…
Spatiokinematic models of five nova remnants: correlations between nova shell axial ratio, expansion velocity, and speed class
Guerrero, M. A.; Toalá, J. A.; Santamaría, E. +3 more
We present long-slit intermediate-dispersion spectroscopic observations and narrow-band direct imaging of four classical nova shells, namely T Aur, HR Del, DQ Her, and QU Vul, and the nova-like source CK Vul. These are used to construct models of their nebular remnants using the morphokinematic modelling tool SHAPE to reveal their 3D shape. All th…
Extracting the Heliographic Coordinates of Coronal Rays Using Images from WISPR/Parker Solar Probe
Riley, P.; Qiu, J.; Stenborg, G. +5 more
The Wide-field Imager for Solar Probe (WISPR) onboard Parker Solar Probe (PSP), observing in white light, has a fixed angular field of view, extending from 13.5∘ to 108∘ from the Sun and approximately 50∘ in the transverse direction. In January 2021, on its seventh orbit, PSP crossed the heliospheric current sheet …
Polarization, polarizing efficiency, and grain alignment towards the direction of the cluster NGC 2345
Hoang, Thiem; Pandey, Jeewan C.; Singh, Sadhana
We have investigated the grain alignment and dust properties towards the direction of the cluster NGC 2345 using the multiband optical polarimetric observations. For the majority of the stars, the observed polarization is found to be due to the interstellar medium with average values of maximum polarization and wavelength corresponding to it as 1.…
Gamma-Ray Diagnostics of r-process Nucleosynthesis in the Remnants of Galactic Binary Neutron-star Mergers
Katsuda, Satoru; Terada, Yukikatsu; Bamba, Aya +4 more
We perform a full nuclear-network numerical calculation of the r-process nuclei in binary neutron-star mergers (NSMs), with the aim of estimating gamma-ray emissions from the remnants of Galactic NSMs up to 106 yr old. The nucleosynthesis calculation of 4070 nuclei is adopted to provide the elemental composition ratios of nuclei with an…