Search Publications

Data-Based Modeling of the Magnetosheath Magnetic Field
DOI: 10.1029/2023JA031665 Bibcode: 2023JGRA..12831665T

Semenov, V. S.; Erkaev, N. V.; Tsyganenko, N. A.

A quantitative model of the magnetosheath (MS) magnetic structure is developed, using a multi-year set of Geotail, Themis, Cluster, and MMS magnetometer and plasma instrument data. The MS database is created using an identification algorithm, based on observed magnetic field magnitudes and proton densities, normalized by their concurrent interplan…

2023 Journal of Geophysical Research (Space Physics)
Cluster 4
The morphology of exciting dark matter and the galactic 511 keV signal
DOI: 10.1088/1475-7516/2023/11/003 Bibcode: 2023JCAP...11..003C

Vincent, Aaron C.; Cappiello, Christopher V.; Jafs, Michael

We study the morphology of the 511 keV signal that could be produced by exciting dark matter (XDM) in the Milky Way. In this model, collisions between dark matter particles excite the dark matter to a state that can then decay back to the ground state, releasing an electron-positron pair. These electrons and positrons would then annihilate, produc…

2023 Journal of Cosmology and Astroparticle Physics
INTEGRAL 4
Minor species in Venus' night side troposphere as observed by VIRTIS-H/Venus Express
DOI: 10.1016/j.icarus.2023.115714 Bibcode: 2023Icar..40515714M

Robert, S.; Montmessin, F.; Bertaux, J. -L. +10 more

The 2 . 3 µm spectral window has been used to constrain the composition of the lower atmosphere (in the 30-40 km altitude range) on the night side of Venus for more than thirty years. Here, we present a follow-up study of Marcq et al. (2008), but using the full VIRTIS-H/Venus Express data archive as well as an updated radiative transfer forw…

2023 Icarus
VenusExpress 4
Exotic image formation in strong gravitational lensing by clusters of galaxies - IV. Elliptical NFW lenses and hyperbolic umbilics
DOI: 10.1093/mnras/stad2978 Bibcode: 2023MNRAS.526.3902M

Meena, Ashish Kumar; Bagla, Jasjeet Singh

A source lying near a hyperbolic umbilic (HU) singularity leads to a ring-like image formation, constituting four images with high magnification factors and lying in a small region of the lens plane. Since (based on our earlier work) the observed number of HU image formations in cluster lenses is expected to increase in the future, it is timely to…

2023 Monthly Notices of the Royal Astronomical Society
eHST 4
SPT-CL J2215-3537: A Massive Starburst at the Center of the Most Distant Relaxed Galaxy Cluster
DOI: 10.3847/1538-4357/acc6c2 Bibcode: 2023ApJ...947...44C

Mahler, Guillaume; Allen, Steven W.; Sharon, Keren +15 more

We present the discovery of the most distant, dynamically relaxed cool core cluster, SPT-CL J2215-3537 (SPT2215), and its central brightest cluster galaxy (BCG) at z = 1.16. Using new X-ray observations, we demonstrate that SPT2215 harbors a strong cool core with a central cooling time of 200 Myr (at 10 kpc) and a maximal intracluster medium cooli…

2023 The Astrophysical Journal
eHST 4
The imprint of bursty star formation on alpha-element abundance patterns in Milky Way-like galaxies
DOI: 10.1093/mnras/stad206 Bibcode: 2023MNRAS.520.1672P

Bailin, Jeremy; Stern, Jonathan; Faucher-Giguère, Claude-André +5 more

Milky Way-mass galaxies in the FIRE-2 simulations demonstrate two main modes of star formation. At high redshifts star formation occurs in a series of short and intense bursts, while at low redshifts star formation proceeds at a steady rate with a transition from one mode to another at times ranging from 3 to 7 Gyr ago for different galaxies. We a…

2023 Monthly Notices of the Royal Astronomical Society
Gaia 4
Undulated Shock Surface Formed After a Shock-Discontinuity Interaction
DOI: 10.1029/2023GL103848 Bibcode: 2023GeoRL..5003848Z

Shen, Chao; Zhou, Yufei; Ji, Yong

Shock ripples and shock-discontinuity interactions (SDIs) have long been proposed to explain the frequent occurrence of high-speed jets (HSJs) in the magnetosheath; however, there is no direct observational evidence for either of them occurring near a shock. Herein, we report a large-scale, long-duration undulated quasi-perpendicular shock surface…

2023 Geophysical Research Letters
Cluster 4
Dynamical state of the globular clusters Rup 106 and IC 4499
DOI: 10.1051/0004-6361/202244288 Bibcode: 2023A&A...670A..11B

Dalessandro, E.; Beccari, G.; Cadelano, M.

The dynamical evolution of globular clusters is theoretically described by a series of well-known events typical of N-body systems. Still, the identification of observational signatures able to empirically describe the stage of dynamical evolution of a stellar system with a density typical of a globular cluster represents a challenge. In this pape…

2023 Astronomy and Astrophysics
Gaia eHST 4
Temperature diagnostics of chromospheric fibrils
DOI: 10.1051/0004-6361/202245527 Bibcode: 2023A&A...672A..89K

Oliver, R.; Kuridze, D.; Kriginsky, M.

Context. Chromospheric fibrils are thin and elongated structures that connect nearby photospheric magnetic field concentrations of opposite polarities.
Aims: We assess the possibilities and drawbacks related to the use of current instrumentation and inversion techniques to infer the thermodynamic structure of chromospheric fibrils.
Metho…

2023 Astronomy and Astrophysics
IRIS 4
Ionized-gas Metallicity of the Strong [O III]λ5007 Emission-line Compact Galaxies in the LAMOST Survey
DOI: 10.3847/1538-4365/acd69c Bibcode: 2023ApJS..267...16L

Luo, A. -Li; Kong, Xiao; Zhao, Yong-Heng +4 more

This article reports a sample of 1830 strong [O III]λ5007 emission-line compact galaxies discovered with the LAMOST spectroscopic survey and the photometric catalog of the Sloan Digital Sky Survey. We newly identify 402 spectra of 346 strong [O III]λ5007 emission-line compact galaxies by finding compact isolated point sources. Combined with the sa…

2023 The Astrophysical Journal Supplement Series
eHST JWST 4