Search Publications
Powerful Radio-loud Quasars Are Triggered by Galaxy Mergers in the Cosmic Bright Ages
Baum, Stefi A.; O'Dea, Christopher P.; Perlman, Eric S. +15 more
While supermassive black holes are ubiquitous features of galactic nuclei, only a small minority are observed during episodes of luminous accretion. The physical mechanism(s) driving the onset of fueling and ignition in these active galactic nuclei (AGN) are still largely unknown for many galaxies and AGN-selection criteria. Attention has focused …
A 500 pc volume-limited sample of hot subluminous stars. I. Space density, scale height, and population properties
Geier, S.; Kepler, S. O.; Heber, U. +25 more
We present the first volume-limited sample of spectroscopically confirmed hot subluminous stars out to 500 pc, defined using the accurate parallax measurements from the Gaia space mission data release 3 (DR3). The sample comprises a total of 397 members, with 305 (~77%) identified as hot subdwarf stars, including 83 newly discovered systems. Of th…
TESS and ESPRESSO discover a super-Earth and a mini-Neptune orbiting the K-dwarf TOI-238*
Bouchy, F.; Rebolo, R.; Pallé, E. +53 more
The number of super-Earth and mini-Neptune planet discoveries has increased significantly in the last two decades thanks to transit and radial velocity (RV) surveys. When it is possible to apply both techniques, we can characterise the internal composition of exoplanets, which in turn provides unique insights on their architecture, formation and e…
The Stellar Distribution in Ultrafaint Dwarf Galaxies Suggests Deviations from the Collisionless Cold Dark Matter Paradigm
Trujillo, Ignacio; Sánchez Almeida, Jorge; Plastino, Angel R.
Unraveling the nature of dark matter (DM) stands as a primary objective in modern physics. Here we present evidence suggesting deviations from the collisionless cold DM (CDM) paradigm. It arises from the radial distribution of stars in six ultrafaint dwarf (UFD) galaxies measured with the Hubble Space Telescope. After a trivial renormalization in …
Small-amplitude Compressible Magnetohydrodynamic Turbulence Modulated by Collisionless Damping in Earth's Magnetosheath: Observation Matches Theory
Liu, Terry Z.; Zhao, Siqi; Yan, Huirong +2 more
Plasma turbulence is a ubiquitous dynamical process that transfers energy across many spatial and temporal scales and affects energetic particle transport. Recent advances in the understanding of compressible magnetohydrodynamic (MHD) turbulence demonstrate the important role of damping in shaping energy distributions on small scales, yet its obse…
Subrelativistic Outflow and Hours-timescale Large-amplitude X-Ray Dips during Super-Eddington Accretion onto a Low-mass Massive Black Hole in the Tidal Disruption Event AT2022lri
Kulkarni, S. R.; Cenko, S. Bradley; Sollerman, Jesper +32 more
We present the tidal disruption event (TDE) AT2022lri, hosted in a nearby (≈144 Mpc) quiescent galaxy with a low-mass massive black hole (104 M ⊙ < M BH < 106 M ⊙). AT2022lri belongs to the TDE-H+He subtype. More than 1 Ms of X-ray data were collected with NICER, Swift, and XMM-Newton fr…
Is there a black hole in the center of the Sun?
Bellinger, Earl P.; Caplan, Matthew E.; Santarelli, Andrew D.
There is probably not a black hole in the center of the Sun. Despite this detail, our goal in this work to convince the reader that this question is interesting and that work studying stars with central black holes is well motivated. If primordial black holes exist then they may exist in sufficiently large numbers to explain the dark matter in the…
The VISTA Variables in the Vía Láctea extended (VVVX) ESO public survey: Completion of the observations and legacy
Tamura, M.; Schultheis, M.; Minniti, D. +143 more
Context. The ESO public survey VISTA Variables in the Vía Láctea (VVV) surveyed the inner Galactic bulge and the adjacent southern Galactic disk from 2009–2015. Upon its conclusion, the complementary VVV extended (VVVX) survey has expanded both the temporal as well as spatial coverage of the original VVV area, widening it from 562 to 1700 sq. deg.…
β Cephei Pulsators in Eclipsing Binaries Observed with TESS
Handler, Gerald; Eze, Christian I.
The combined strength of asteroseismology and empirical stellar basic parameter determinations for in-depth asteroseismic analysis of massive pulsators in eclipsing binaries shows great potential for treating the challenging and mysterious discrepancies between observations and models of stellar structure and the evolution of massive stars. This p…
Tracing the rise of supermassive black holes. A panchromatic search for faint, unobscured quasars at z ≳ 6 with COSMOS-Web and other surveys
Casey, Caitlin M.; Koekemoer, Anton M.; Wilkins, Stephen M. +20 more
We report the identification of 64 new candidates of compact galaxies, potentially hosting faint quasars with bolometric luminosities of Lbol = 1043-1046 erg s−1, residing in the reionization epoch within the redshift range of 6 ≲ z ≲ 8. These candidates were selected by harnessing the rich multiband dat…