Search Publications
WISDOM project - VII. Molecular gas measurement of the supermassive black hole mass in the elliptical galaxy NGC 7052
Williams, Thomas G.; Sarzi, Marc; Cappellari, Michele +7 more
Supermassive black hole (SMBH) masses can be measured by resolving the dynamical influences of the SMBHs on tracers of the central potentials. Modern long-baseline interferometers have enabled the use of molecular gas as such a tracer. We present here Atacama Large Millimeter/submillimeter Array observations of the elliptical galaxy NGC 7052 at 0.…
Tracing PAH Size in Prominent Nearby Mid-Infrared Environments
Tielens, A. G. G. M.; Peeters, E.; Vacca, W. D. +2 more
We present observations from the First Light Infrared TEst CAMera (FLITECAM) on board the Stratospheric Observatory for Infrared Astronomy, the Spitzer Infrared Array Camera (IRAC), and the Spitzer Infrared Spectrograph SH mode in three well-known photodissociation regions, the reflection nebulae (RNe) NGC 7023 and NGC 2023 and to the southeast of…
Correction to the Photometric Magnitudes of the Gaia Early Data Release 3
Huang, Yang; Niu, Zexi; Yuan, Haibo +4 more
In this Letter, we have carried out an independent validation of the Gaia Early Data Release 3 (EDR3) photometry using approximately 10,000 Landolt standard stars from Clem & Landolt (2013). Using a machine-learning technique, the UBVRI magnitudes are converted into the Gaia magnitudes and colors and then compared to those in the EDR3, with th…
A method for finding anomalous astronomical light curves and their analogues
Graham, Matthew J.; Giles, Daniel; Mahabal, Ashish A. +4 more
Our understanding of the Universe has profited from deliberate targeted studies of known phenomena, as well as from serendipitous unexpected discoveries, such as the discovery of a complex variability pattern in the direction of KIC 8462852 (Boyajian's star). Upcoming surveys such as the Vera C. Rubin Observatory Legacy Survey of Space and Time wi…
A proto-helium white dwarf stripped by a substellar companion via common-envelope ejection. Uncovering the true nature of a candidate hypervelocity B-type star
Geier, S.; Heber, U.; Irrgang, A. +3 more
In the past, SDSS J160429.12+100002.2 wass spectroscopically classified as a blue horizontal branch (BHB) star. Assuming a luminosity that is characteristic of BHB stars, the object's radial velocity and proper motions from Gaia Early Data Release 3 would imply that its Galactic rest-frame velocity exceeds its local escape velocity. Consequently, …
The centres of M83 and the Milky Way: opposite extremes of a common star formation cycle
Henshaw, Jonathan D.; Kruijssen, J. M. Diederik; Longmore, Steven N. +8 more
In the centres of the Milky Way and M83, the global environmental properties thought to control star formation are very similar. However, M83's nuclear star formation rate (SFR), as estimated by synchrotron and H α emission, is an order of magnitude higher than the Milky Way's. To understand the origin of this difference we use ALMA observations o…
TeV Cosmic-Ray Nucleus Acceleration in Shell-type Supernova Remnants with Hard γ-Ray Spectra
Zhang, Shuinai; Liu, Siming; Zeng, Houdun +1 more
The emission mechanism for hard γ-ray spectra from supernova remnants (SNRs) is still a matter of debate. Recent multiwavelength observations of the TeV source HESS J1912+101 show that it is associated with an SNR with an age of ∼100 kyr, making it unlikely produce the TeV γ-ray emission via leptonic processes. We analyzed Fermi observations of it…
Locating the gamma-ray emission region in the brightest Fermi-LAT flat-spectrum radio quasars
Brown, Anthony M.; Acharyya, Atreya; Chadwick, Paula M.
We present a temporal and spectral analysis of the gamma-ray flux from nine of the brightest flat-spectrum radio quasars (FSRQs) detected with the Fermi Large Area Telescope during its first 8 yr of operation, with the aim of constraining the location of the emission region. Using the increased photon statistics obtained from the two brightest fla…
Gauging the effect of supermassive black holes feedback on quasar host galaxies
Kraemer, S. B.; Crenshaw, D. M.; Storchi-Bergmann, T. +6 more
In order to gauge the role that active galactic nuclei play in the evolution of galaxies via the effect of kinetic feedback in nearby QSO 2's (z ~ 0.3), we observed eight such objects with bolometric luminosities $L_{bol} \sim 10^{46}\rm {erg\, s^{-1}}$ using Gemini Multi-Object Spectrograph-integral field units. The emission lines were fitted wit…
GRAVITY K-band spectroscopy of HD 206893 B. Brown dwarf or exoplanet
Lutz, D.; Genzel, R.; Sturm, E. +93 more
Context. Near-infrared interferometry has become a powerful tool for studying the orbital and atmospheric parameters of substellar companions.
Aims: We aim to reveal the nature of the reddest known substellar companion HD 206893 B by studying its near-infrared colors and spectral morphology and by investigating its orbital motion.
Method…