Search Publications
Cassini spacecraft reveals global energy imbalance of Saturn
West, Robert A.; Nixon, Conor A.; Guillot, Tristan +16 more
The global energy budget is pivotal to understanding planetary evolution and climate behaviors. Assessing the energy budget of giant planets, particularly those with large seasonal cycles, however, remains a challenge without long-term observations. Evolution models of Saturn cannot explain its estimated Bond albedo and internal heat flux, mainly …
Young Stellar Objects in NGC 346: A JWST NIRCam/MIRI Imaging Survey
Hirschauer, Alec S.; Fahrion, Katja; Lenkić, Laura +17 more
We present a JWST imaging survey with NIRCam and MIRI of NGC 346, the brightest star-forming region in the Small Magellanic Cloud. By combining aperture and point-spread function photometry of 11 wavelength bands across these two instruments, we have detected more than 200,000 unique sources. Using a near-infrared color analysis, we observe variou…
OGLE-BLAP-009 - a case study for the properties and evolution of blue large-amplitude pulsators
Kupfer, Thomas; van Roestel, Jan; Bildsten, Lars +5 more
Blue large-amplitude pulsators (BLAPs) make up a rare class of hot pulsating stars with effective temperatures of ≈30 000 K and surface gravities of 4.0-5.0 dex (cgs). The evolutionary origin and current status of BLAPs is not well understood, largely based on a lack of spectroscopic observations and no available mass constraints. However, several…
The properties of AGN in dwarf galaxies identified via SED fitting
Smith, D. J. B.; Kaviraj, S.; Watkins, A. E. +5 more
Given their dominance of the galaxy number density, dwarf galaxies are central to our understanding of galaxy formation. While the incidence of active galactic nuclei (AGN) and their impact on galaxy evolution have been extensively studied in massive galaxies, much less is known about the role of AGN in the evolution of dwarfs. We search for radia…
A Two-zone Accretion Disk in the Changing-look Active Galactic Nucleus 1ES 1927+654: Physical Implications for Tidal Disruption Events and Super-Eddington Accretion
Ho, Luis C.; Ricci, Claudio; Trakhtenbrot, Benny +1 more
The properties of slim accretion disks, while crucial for our understanding of black hole growth, have yet to be studied extensively observationally. We analyze the multiepoch broadband spectral energy distribution of the changing-look active galactic nucleus 1ES 1927+654 to derive the properties of its complex, time-dependent accretion flow. The …
A first rapid synoptic magnetic field map using SDO/HMI and SO/PHI data
Schmidt, W.; Woch, J.; Solanki, S. K. +47 more
Context. Traditionally, the observation time needed to build synoptic maps of the solar magnetic field is bound to the 27 days of a full Carrington rotation due to the single viewpoint from Earth.
Aims: Our aim is to reduce this observation time to 13.5 days by combining magnetograms from two vantage points, 180° apart in longitude in the ide…
The XXL Survey. LI. Pressure profile and YSZ − M scaling relation in three low-mass galaxy clusters at z ∼ 1 observed with NIKA2
Berta, S.; Altieri, B.; Aussel, H. +64 more
Context. The thermodynamical properties of the intracluster medium (ICM) are driven by scale-free gravitational collapse, but they also reflect the rich astrophysical processes at play in galaxy clusters. At low masses (∼1014 M⊙) and high redshift (z ≳ 1), these properties remain poorly constrained, observationally speaking, …
JWST-TST High Contrast: JWST/NIRCam Observations of the Young Giant Planet β Pic b
Stark, Christopher C.; Valenti, Jeff A.; van der Marel, Roeland P. +14 more
We present the first JWST/NIRCam observations of the directly imaged gas giant exoplanet β Pic b. Observations in six filters using NIRCam's round coronagraphic masks provide a high-signal-to-noise-ratio detection of β Pic b and the archetypal debris disk around β Pic over a wavelength range of ∼1.7–5 µm. This paper focuses on the detection …
Beyond Point Masses. III. Detecting Haumea's Nonspherical Gravitational Field
Grundy, Will M.; Oldroyd, William J.; Proudfoot, Benjamin C. N. +3 more
The dwarf planet Haumea is one of the most compelling trans-Neptunian objects to study, hosting two small, dynamically interacting satellites, a family of nearby spectrally unique objects, and a ring system. Haumea itself is extremely oblate due to its 3.9 hr rotation period. Understanding the orbits of Haumea's satellites, named Hi'iaka and Namak…
Exploring the Mpc Environment of the Quasar ULAS J1342+0928 at z = 7.54
Finkelstein, Steven L.; Willott, Chris J.; Brammer, Gabriel +10 more
Theoretical models predict that z ≳ 6 quasars are hosted in the most massive halos of the underlying dark matter distribution and thus would be immersed in protoclusters of galaxies. However, observations report inconclusive results. We investigate the 1.1 proper-Mpc2 environment of the z = 7.54 luminous quasar ULAS J1342+0928. We searc…