Search Publications
ULF Waves Propagating Through the Martian Magnetosheath into the Ionosphere: A Statistical Study Using Mars Express Observations
Fraenz, Markus; Echer, Ezequiel; Franco, Adriane Marques de Souza +1 more
The Martian magnetosphere is induced, and the low-energy ion escape is related to the extreme ultraviolet (EUV) solar radiation and to the solar wind pressure variations. The ion reflection at the bow shock is a permanent source of ultra-low frequency (ULF) waves. These are convected through the magnetosheath and can penetrate into the upper ionos…
A Simple Method for Predicting N H Variability in Active Galactic Nuclei
Marchesi, Stefano; Zhao, Xiurui; Ajello, Marco +4 more
The unified model of active galactic nuclei (AGNs) includes a geometrically thick obscuring medium to explain the differences between type I and type II AGNs as an effect of inclination angle. This medium is often referred to as the torus and is thought to be "clumpy" as the line-of-sight column density, N H, has been observed to vary i…
A Census of Archival X-Ray Spectra for Modeling Tidal Disruption Events
Wen, Sixiang; Jonker, Peter G.; Stone, Nicholas C. +3 more
Tidal disruption events (TDEs) are highly energetic phenomena that occur when a star is tidally disrupted by the central massive black hole in a galaxy. Fitting the observed X-ray spectra of TDEs with a first-principles, general-relativistic slim-disk model for the emission from the inner accretion disk can constrain the black hole mass M •
Statistical Mapping of Magnetic Topology at Venus
Persson, Moa; Xu, Shaosui; Frahm, Rudy A. +3 more
Despite Venus having insignificant intrinsic magnetic fields, the magnetic connectivity between the solar wind and the Venus ionosphere, or magnetic topology, is not as simple as expected and is also important for characterizing the Venus space environment. This study provides a technique combining superthermal electron energy and pitch angle dist…
A high-latitude coronal mass ejection observed by a constellation of coronagraphs: Solar Orbiter/Metis, STEREO-A/COR2, and SOHO/LASCO
Perri, S.; Sasso, C.; Romoli, M. +35 more
Context. A few days before the first perihelion of the Solar Orbiter nominal mission, which occurred on 2022 March 26, the Metis coronagraph on board Solar Orbiter detected a coronal mass ejection (CME) that was moving away from the far side of the Sun (with respect to Solar Orbiter) at high northern latitudes. The eruption was also seen by other …
Probing Reflection from Aerosols with the Near-infrared Dayside Spectrum of WASP-80b
Fortney, Jonathan J.; Stevenson, Kevin B.; Désert, Jean-Michel +9 more
The presence of aerosols is intimately linked to the global energy budget and the composition of a planet's atmosphere. Their ability to reflect incoming light prevents energy from being deposited into the atmosphere, and they shape the spectra of exoplanets. We observed five near-infrared secondary eclipses of WASP-80b with the Wide Field Camera …
Investigation of the connection between X-ray binaries and compact star clusters in NGC 628
Akyuz, A.; Aksaker, N.; Avdan, S. +3 more
We investigated for a possible connection between the types of X-ray binaries (XRBs) and the properties of compact star clusters in the nearby galaxy NGC 628. Using Chandra archival data covering the years 2001-2018, 75 X-ray sources were detected within the field of view of observations. A total of 69 XRBs, one of which is an ultraluminous X-ray …
JWST Reveals Widespread CO Ice and Gas Absorption in the Galactic Center Cloud G0.253+0.016
Lu, Xing; Henshaw, Jonathan D.; Ginsburg, Adam +7 more
We report JWST NIRCam observations of G0.253+0.016, the molecular cloud in the Central Molecular Zone known as "The Brick," with the F182M, F187N, F212N, F410M, F405N, and F466N filters. We catalog 56,146 stars detected in all six filters using the crowdsource package. Stars within and behind The Brick exhibit prodigious absorption in the F466N fi…
The IR Compactness of Dusty Galaxies Sets Star Formation and Dust Properties at z ∼ 0-2
Kirkpatrick, Allison; Inami, Hanae; McKinney, Jed +9 more
The surface densities of gas, dust, and stars provide a window into the physics of star formation that, until the advent of high-resolution far-IR/submillimeter observations, has been historically difficult to assess among dusty galaxies. To study the link between IR surface densities and dust properties, we leverage the Atacama Large Millimetre/S…
Discovery of a radio jet in the Cloverleaf quasar at z = 2.56
Tsai, Chao-Wei; Wang, Junzhi; Zhang, Zhi-Yu +10 more
The fast growth of supermassive black holes and their feedback to the host galaxies play an important role in regulating the evolution of galaxies, especially in the early Universe. However, due to cosmological dimming and the limited angular resolution of most observations, it is difficult to resolve the feedback from the active galactic nuclei (…