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Double Shells of the Planetary Nebula NGC 7009 Minor Axis
DOI: 10.3847/1538-4357/ac90c3 Bibcode: 2022ApJ...938...71L

Otsuka, Masaaki; Hyung, Siek; Lee, Seong-Jae

We analyzed the minor-axis spectra of the elliptical planetary nebula (PN) NGC 7009 observed with Keck HIRES with a 0.″862 × 10″ slit placed at about 7.″5 and 10″ away from the center and a 0.″862 × 14″ slit at the center. The mean densities derived from the integrated [S II] 6716/6731 Å fluxes along the Keck HIRES slit length indicate a density r…

2022 The Astrophysical Journal
eHST 3
The Influence of Localized Dynamics on Dusk-Dawn Convection in the Earth's Magnetotail
DOI: 10.1029/2021JA030057 Bibcode: 2022JGRA..12730057L

Case, N. A.; Grocott, A.; Lane, J. H.

Previous work has shown that earthward convective flow bursts in the magnetotail have a dusk-dawn (v⊥y) component that is controlled by the historical state of the Interplanetary Magnetic Field (IMF) By component. Here, we analyze 27 years of Cluster, THEMIS and Geotail plasma and magnetic field data and identify 1,639 magnet…

2022 Journal of Geophysical Research (Space Physics)
Cluster 3
Solar Wind Velocities at Comets C/2011 L4 Pan-STARRS and C/2013 R1 Lovejoy Derived Using a New Image Analysis Technique
DOI: 10.1029/2021JA029799 Bibcode: 2022JGRA..12729799R

Jones, Geraint H.; Ramanjooloo, Yudish

The ion tails of bright comets have long been considered as a natural tracers of the solar wind (SW) near these objects. Studies of comets and their ion tails allow inexpensive monitoring of key SW structures in the inner heliosphere, much of which is otherwise only accessible by in situ SW spacecraft measurements. Here, we present a novel techniq…

2022 Journal of Geophysical Research (Space Physics)
SOHO 3
On the Unusual Variability of 2MASS J06195260-2903592: A Long-lived Disk around a Young Ultracool Dwarf
DOI: 10.3847/1538-3881/ac8cee Bibcode: 2022AJ....164..165L

Magnier, Eugene A.; Gaidos, Eric; Shappee, Benjamin J. +11 more

We present the characterization of the low-gravity M6 dwarf 2MASS J06195260-2903592, previously identified as an unusual field object based on its strong IR excess and variable near-IR spectrum. Multiple epochs of low-resolution (R ≈ 150) near-IR spectra show large-amplitude (≈0.1-0.5 mag) continuum variations on timescales of days to 12 yr, unlik…

2022 The Astronomical Journal
Gaia 3
The MOSDEF survey: towards a complete census of the z 2.3 star-forming galaxy population
DOI: 10.1093/mnras/stac2402 Bibcode: 2022MNRAS.517.4337R

Barro, Guillermo; Siana, Brian; Shapley, Alice E. +16 more

We analyse the completeness of the MOSDEF survey, in which z ~ 2 galaxies were selected for rest-optical spectroscopy from well-studied HST extragalactic legacy fields down to a fixed rest-optical magnitude limit (HAB = 24.5). The subset of z ~ 2 MOSDEF galaxies with high signal-to-noise (S/N) emission-line detections analysed in previo…

2022 Monthly Notices of the Royal Astronomical Society
eHST 3
The Solar Wind at (16) Psyche: Predictions for a Metal World
DOI: 10.3847/1538-4357/ac51d7 Bibcode: 2022ApJ...927..202C

Collinson, Glyn A.; Chen, Li-Jen; Jian, Lan K. +1 more

NASA's Psyche spacecraft will carry a magnetometer to main-belt asteroid (16) Psyche to search for remanent magnetic fields, and to attempt electromagnetic sounding of the interior. However, the Psyche spacecraft does not carry an instrument to measure solar wind plasmas. We thus combine data from five missions that have measured the solar wind at…

2022 The Astrophysical Journal
Ulysses 3
A Spectroscopic View of the JWST/GTO Strong Lensing Cluster A1489
DOI: 10.3847/1538-4357/ac67a8 Bibcode: 2022ApJ...930..156R

Diaferio, Antonaldo; Geller, Margaret J.; Rines, Kenneth J. +1 more

We discuss a spectroscopic survey of the strong lensing cluster A1489 that includes redshifts for 195 cluster members along with central velocity dispersions for 188 cluster members. The caustic technique applied to the redshift survey gives the dynamical parameters M 200 = (1.25 ± 0.09) × 1015 M , R 200

2022 The Astrophysical Journal
eHST 3
Comparing Quasi-Parallel and Quasi-Perpendicular Configuration in the Terrestrial Magnetosheath: Multifractal Analysis
DOI: 10.3389/fphy.2022.903632 Bibcode: 2022FrP....10.3632G

Sorriso-Valvo, Luca; Burgess, David; Yordanova, Emiliya +4 more

The terrestrial magnetosheath is characterized by large-amplitude magnetic field fluctuations. In some regions, and depending on the bow-shock geometry, these can be observed on several scales, and show the typical signatures of magnetohydrodynamic turbulence. Using Cluster data, magnetic field spectra and flatness are observed in two intervals se…

2022 Frontiers in Physics
Cluster 3
Mass-Velocity Dispersion Relation by Using the Gaia Data and Its Effect on Interpreting Short-duration and Degenerate Microlensing Events
DOI: 10.3847/1538-3881/ac82e9 Bibcode: 2022AJ....164..112S

Sajadian, Sedighe; Rahvar, Sohrab; Kazemian, Fatemeh

Gravitational microlensing, the lensing of stars in the Milky Way with other stars, has been used for exploring compact dark matter objects, exoplanets, and black holes. The duration of microlensing events, the so-called Einstein crossing time, is a function of distance, mass, and velocities of lens objects. Lenses with different ages and masses m…

2022 The Astronomical Journal
Gaia 3
Stellar Population Astrophysics (SPA) with the TNG. α-elements, lithium, sodium and aluminum in 16 open clusters
DOI: 10.1051/0004-6361/202243593 Bibcode: 2022A&A...667A.103Z

Vallenari, A.; Bragaglia, A.; Spina, L. +13 more

Context. Exploring the Galactic chemical evolution and enrichment scenarios with open clusters (OCs) allows us to understand the history of the Milky Way disk. High-resolution spectra of OCs are a crucial tool, as they provide precise chemical information, to combine with precise distances and ages.
Aims: The aim of the Stellar Population Ast…

2022 Astronomy and Astrophysics
Gaia 3