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Milky Way archaeology using RR Lyrae and type II Cepheids. I. The Orphan stream in 7D using RR Lyrae stars
DOI: 10.1051/0004-6361/202140422 Bibcode: 2021A&A...648A..78P

Lemasle, B.; Thévenin, F.; Altavilla, G. +19 more

We present a chemo-dynamical study of the Orphan stellar stream using a catalog of RR Lyrae pulsating variable stars for which photometric, astrometric, and spectroscopic data are available. Employing low-resolution spectra from the Sloan Digital Sky Survey (SDSS), we determined line-of-sight velocities for individual exposures and derived the sys…

2021 Astronomy and Astrophysics
Gaia 19
Acoustic-gravity wave propagation characteristics in three-dimensional radiation hydrodynamic simulations of the solar atmosphere
DOI: 10.1098/rsta.2020.0170 Bibcode: 2021RSPTA.37900170F

Carlsson, M.; Rempel, M.; Fleck, B. +3 more

There has been tremendous progress in the degree of realism of three-dimensional radiation magneto-hydrodynamic simulations of the solar atmosphere in the past decades. Four of the most frequently used numerical codes are Bifrost, CO5BOLD, MANCHA3D and MURaM. Here we test and compare the wave propagation characteristics in model runs from these fo…

2021 Philosophical Transactions of the Royal Society of London Series A
Hinode SOHO 19
Spectroscopy of the first resolved strongly lensed Type Ia supernova iPTF16geu
DOI: 10.1093/mnras/staa3829 Bibcode: 2021MNRAS.502..510J

Cenko, S. B.; Kulkarni, S. R.; Nugent, P. E. +14 more

We report the results from spectroscopic observations of the multiple images of the strongly lensed Type Ia supernova (SN Ia), iPTF16geu, obtained with ground-based telescopes and the Hubble Space Telescope (HST). From a single epoch of slitless spectroscopy with HST, we resolve spectra of individual lensed supernova images for the first time. Thi…

2021 Monthly Notices of the Royal Astronomical Society
eHST 19
"Worst-case" Microlensing in the Identification and Modeling of Lensed Quasars
DOI: 10.3847/1538-4357/ac2228 Bibcode: 2021ApJ...922...70W

Schechter, Paul L.; Weisenbach, Luke; Pontula, Sahil

Although microlensing of macrolensed quasars and supernovae provides unique opportunities for several kinds of investigations, it can add unwanted and sometimes substantial noise. While microlensing flux anomalies may be safely ignored for some observations, they severely limit others. "Worst-case" estimates can inform the decision whether or not …

2021 The Astrophysical Journal
Gaia 19
Discovery and origins of giant optical nebulae surrounding quasar PKS 0454-22
DOI: 10.1093/mnras/stab1647 Bibcode: 2021MNRAS.505.5497H

Johnson, Sean D.; Chen, Hsiao-Wen; Greene, Jenny E. +1 more

We report optical integral-field spectroscopy in the field of one of the most luminous quasars in the z < 1 Universe, PKS 0454-22, with the Multi-Unit Spectroscopic Explorer. These data enable the discovery of three large ionized nebulae emitting in [O II], H β, and [O III] with projected areas of 1720, 1520, and 130 pkpc2, which we …

2021 Monthly Notices of the Royal Astronomical Society
eHST 19
Modeling a Coronal Mass Ejection from an Extended Filament Channel. I. Eruption and Early Evolution
DOI: 10.3847/1538-4357/abf9a9 Bibcode: 2021ApJ...914...39L

Kazachenko, Maria D.; Lynch, Benjamin J.; Palmerio, Erika +4 more

We present observations and modeling of the magnetic field configuration, morphology, and dynamics of a large-scale, high-latitude filament eruption observed by the Solar Dynamics Observatory. We analyze the 2015 July 9-10 filament eruption and the evolution of the resulting coronal mass ejection (CME) through the solar corona. The slow streamer-b…

2021 The Astrophysical Journal
SOHO 19
Stellar flares from blended and neighbouring stars in Kepler short cadence observations
DOI: 10.1093/mnras/stab166 Bibcode: 2021MNRAS.502.2033J

Loyd, R. O. Parke; Jackman, James A. G.; Shkolnik, Evgenya

We present the results of a search for stellar flares from stars neighbouring the target sources in the Kepler short cadence data. These flares have been discarded as contaminants in previous surveys and therefore provide an unexplored resource of flare events, in particular high-energy events from faint stars. We have measured M dwarf flare energ…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 19
Massive Star Cluster Formation and Destruction in Luminous Infrared Galaxies in GOALS. II. An ACS/WFC3 Survey of Nearby LIRGs
DOI: 10.3847/1538-4357/ac2892 Bibcode: 2021ApJ...923..278L

Surace, J. A.; Inami, H.; Murphy, E. J. +14 more

We present the results of a Hubble Space Telescope WFC3 near-UV and Advanced Camera for Surveys Wide Field Channel optical study into the star cluster populations of a sample of 10 luminous infrared galaxies (LIRGs) in the Great Observatories All-Sky LIRG Survey. Through integrated broadband photometry we have derived ages, masses, and extinctions…

2021 The Astrophysical Journal
eHST 19
The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies. IV. The Star Formation History of Andromeda VII Derived from Long-period Variable Stars
DOI: 10.3847/1538-4357/abdec1 Bibcode: 2021ApJ...910..127N

Javadi, Atefeh; Saremi, Elham; van Loon, Jacco Th. +10 more

We have examined the star formation history (SFH) of Andromeda VII (And VII), the brightest and most massive dwarf spheroidal (dSph) satellite of the Andromeda galaxy (M31). Although M31 is surrounded by several dSph companions with old stellar populations and low metallicity, it has a metal-rich stellar halo with an age of 6-8 Gyr. This indicates…

2021 The Astrophysical Journal
Gaia 19
A Multi-Observing Technique Study of the Dynamical Evolution of the Viscous Disk around the Be Star ω CMa
DOI: 10.3847/1538-4357/abdd1e Bibcode: 2021ApJ...909..149G

Rivinius, Thomas; Baade, Dietrich; Carciofi, Alex C. +3 more

The observed emission lines of Be stars originate from a circumstellar Keplerian disk, which is generally well explained by the viscous decretion disk model. In an earlier work we performed modeling of the full light curve of the bright Be star ω CMa with the 1D time-dependent hydrodynamic code SINGLEBE and the Monte Carlo radiative transfer code …

2021 The Astrophysical Journal
Gaia IUE 19