Search Publications
Complete replacement of magnetic flux in a flux rope during a coronal mass ejection
Veronig, Astrid M.; Li, Ting; Wang, Yuming +5 more
Solar coronal mass ejections are the most energetic events in the Solar System. In their standard formation model, a magnetic flux rope builds up into a coronal mass ejection through magnetic reconnection that continually converts overlying, untwisted magnetic flux into twisted flux enveloping the pre-existing rope. However, only a minority of cor…
Dynamics of Large-Scale Solar Flows
Gizon, Laurent; Noraz, Quentin; Hotta, Hideyuki +2 more
The Sun's axisymmetric large-scale flows, differential rotation and meridional circulation, are thought to be maintained by the influence of rotation on the thermal-convective motions in the solar convection zone. These large-scale flows are crucial for maintaining the Sun's global magnetic field. Over the last several decades, our understanding o…
Early Results from GLASS-JWST. XV. Properties of the Faintest Red Sources in the NIRCAM Deep Fields
Vulcani, B.; Brammer, G.; Treu, T. +20 more
We present a first look at the reddest 2–5 µm sources found in deep images from the GLASS Early Release Science program. We undertake a general search, i.e., not looking for any particular spectral signatures, for sources detected only in bands redder than is reachable with the Hubble Space Telescope, and which would likely not have been ide…
JWST/NIRSpec Observations of the Planetary Mass Companion TWA 27B
Luhman, K. L.; Birkmann, S. M.; Tremblin, P. +8 more
We present 1-5 µm spectroscopy of the young planetary mass companion TWA 27B (2M1207B) performed with NIRSpec on board the James Webb Space Telescope. In these data, the fundamental band of CH4 is absent, and the fundamental band of CO is weak. The nondetection of CH4 reinforces a previously observed trend of weaker CH<…
The Radial Variation of the Solar Wind Turbulence Spectra near the Kinetic Break Scale from Parker Solar Probe Measurements
Bale, S. D.; Kontar, E. P.; Engelbrecht, N. E. +7 more
In this study we examine the radial dependence of the inertial and dissipation range indices, as well as the spectral break separating the inertial and dissipation range in power density spectra of interplanetary magnetic field fluctuations using Parker Solar Probe data from the fifth solar encounter between ~0.1 and ~0.7 au. The derived break wav…
Water Absorption in the Transmission Spectrum of the Water World Candidate GJ 9827 d
Fortney, Jonathan J.; Mikal-Evans, Thomas; Lothringer, Joshua D. +16 more
Recent work on the characterization of small exoplanets has allowed us to accumulate growing evidence that sub-Neptunes with radii greater than ~2.5 R ⊕ often host H2/He-dominated atmospheres both from measurements of their low bulk densities and from direct detections of their low mean molecular mass atmospheres. However, th…
Particle Acceleration by Magnetic Reconnection in Geospace
Khotyaintsev, Yuri; Drake, James F.; Oka, Mitsuo +7 more
Particles are accelerated to very high, non-thermal energies during explosive energy-release phenomena in space, solar, and astrophysical plasma environments. While it has been established that magnetic reconnection plays an important role in the dynamics of Earth's magnetosphere, it remains unclear how magnetic reconnection can further explain pa…
The Interaction between AGN and Starburst Activity in the Circumnuclear Region of NGC 7469 as Viewed with JWST
Ho, Luis C.; Zhang, Lulu
We combine mid-infrared diagnostics obtained from integral-field-unit observations taken with Mid-Infrared Instrument/Medium Resolution Spectrograph on the James Webb Space Telescope with cold molecular gas information derived from Atacama Large Millimeter/submillimeter Array observations of CO(1-0) emission to investigate the star formation rate …
Improving Star Cluster Age Estimates in PHANGS-HST Galaxies and the Impact on Cluster Demographics in NGC 628
Kruijssen, J. M. Diederik; Klessen, Ralf S.; Schinnerer, Eva +29 more
A long-standing problem when deriving the physical properties of stellar populations is the degeneracy between age, reddening, and metallicity. When a single metallicity is used for all the star clusters in a galaxy, this degeneracy can result in 'catastrophic' errors for old globular clusters. Typically, approximately 10-20 per cent of all cluste…
Empirical constraints on the turbulence in QSO host nebulae from velocity structure function measurements
Johnson, Sean D.; Zahedy, Fakhri S.; Chen, Hsiao-Wen +9 more
We present the first empirical constraints on the turbulent velocity field of the diffuse circumgalactic medium around four luminous quasi-stellar objects (QSOs) at z ≈ 0.5-1.1. Spatially extended nebulae of ≈50-100 physical kpc in diameter centred on the QSOs are revealed in [O II] $\lambda \lambda \, 3727,3729$ and/or [O III] $\lambda \, 5008$ e…