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AGN STORM 2. VII. A Frequency-resolved Map of the Accretion Disk in Mrk 817: Simultaneous X-Ray Reverberation and UVOIR Disk Reprocessing Time Lags
Kaspi, Shai; Barth, Aaron J.; Horne, Keith +35 more
X-ray reverberation mapping is a powerful technique for probing the innermost accretion disk, whereas continuum reverberation mapping in the UV, optical, and infrared (UVOIR) reveals reprocessing by the rest of the accretion disk and broad-line region (BLR). We present the time lags of Mrk 817 as a function of temporal frequency measured from 14 m…
The Factory and the Beehive. V. Chromospheric and Coronal Activity and Its Dependence on Rotation in Praesepe and the Hyades
Drake, Jeremy J.; Covey, Kevin R.; Agüeros, Marcel A. +6 more
Low-mass (≲1.2 M ⊙) main-sequence stars lose angular momentum over time, leading to a decrease in their magnetic activity. The details of this rotation–activity relation remain poorly understood, however. Using observations of members of the ≈700 Myr old Praesepe and Hyades open clusters, we aim to characterize the rotation–activity rel…
Why Are (Almost) All the Protostellar Outflows Aligned in Serpens Main?
Manoj, P.; Narang, Mayank; Reiter, Megan +4 more
We present deep 1.4–4.8 µm JWST-NIRCam imaging of the Serpens Main star-forming region and identify 20 candidate protostellar outflows, most with bipolar structure and identified driving sources. The outflow position angles (PAs) are strongly correlated, and they are aligned within ±24° of the major axis of the Serpens filament. These orient…
JWST's First Glimpse of a z > 2 Forming Cluster Reveals a Top-heavy Stellar Mass Function
Daddi, Emanuele; Lu, Shiying; Kodama, Tadayuki +11 more
Clusters and their progenitors (protoclusters) at z ∼ 2 ‑ 4, the peak epoch of star formation, are ideal laboratories to study the formation process of both the clusters themselves and their member galaxies. However, a complete census of their member galaxies has been challenging due to observational difficulties. Here we present new JWST/NIRCam o…
Solar Eruptions in Nested Magnetic Flux Systems
Antiochos, Spiro K.; Kumar, Pankaj; DeVore, C. Richard +2 more
The magnetic topology of erupting regions on the Sun is a key factor in the energy buildup and release, and the subsequent evolution of flares and coronal mass ejections (CMEs). The presence/absence of null points and separatrices dictates whether and where current sheets form and magnetic reconnection occurs. Numerical simulations show that energ…
The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems. IV. NIRISS Aperture Masking Interferometry Performance and Lessons Learned
Henning, Thomas; Fortney, Jonathan J.; Moran, Sarah E. +120 more
We present a performance analysis for the aperture masking interferometry (AMI) mode on board the James Webb Space Telescope Near Infrared Imager and Slitless Spectrograph (JWST/NIRISS). Thanks to self-calibrating observables, AMI accesses inner working angles down to and even within the classical diffraction limit. The scientific potential of thi…
A Photoionization Model for the Infrared Coronal Line Emission in the Classical Nova V1716 Scorpii
Evans, A.; Starrfield, S.; Page, K. L. +2 more
A near-infrared spectrum of nova V1716 Scorpii (PNV J17224490-4137160), a recent bright (
Are WASP-107-like Systems Consistent with High-eccentricity Migration?
Dai, Fei; Yu, Hang
WASP-107 b seems to be a poster child of the long-suspected high-eccentricity migration scenario. It is on a 5.7 day, polar orbit. The planet is Jupiter-like in radius but Neptune-like in mass with exceptionally low density. WASP-107 c is on a 1100 day, e = 0.28 orbit with at least Saturn mass. Planet b may still have a residual eccentricity of 0.…
X-Rays from RS Ophiuchi's 2021 Eruption: Shocks In and Out of Ionization Equilibrium
Sokoloski, J. L.; Mukai, Koji; Islam, Nazma
The recurrent nova RS Ophiuchi (RS Oph) underwent its most recent eruption on 2021 August 8 and became the first nova to produce both detectable GeV and TeV emission. We used extensive X-ray monitoring with the Neutron Star Interior Composition Explorer Mission (NICER) to model the X-ray spectrum and probe the shock conditions throughout the 2021 …
The Atmosphere of HD 149026b: Low Metal Enrichment and Weak Energy Transport
Fortney, Jonathan J.; Batalha, Natasha E.; Mukherjee, Sagnick +1 more
Recent JWST eclipse spectra of the high-density hot Saturn HD 149026b between 2.35 and 5.08 µm have allowed for in-depth study of its atmosphere. To understand its atmospheric properties, we have created a grid of 1D radiative-convective–thermochemical–equilibrium atmosphere models and spectra with PICASO 3.0. In agreement with previous work…