Search Publications
Spatial and velocity offsets of Galactic masers from the centres of spiral arms
Vallée, Jacques P.
Some theories about the spiral arms of galaxies predict an offset between different tracers of star formation. Our goal in this paper is to find such an offset between the observed locations of radio masers and the locations of the arms, using a recent four-arm model fitted to the CO 1-0 gas. Our method is to compare a recent global four-arm spira…
FIGS: spectral fitting constraints on the star formation history of massive galaxies since the cosmic noon
Finkelstein, Steven L.; Pirzkal, Nor; Hathi, Nimish +16 more
We constrain the stellar population properties of a sample of 52 massive galaxies - with stellar mass log (Ms/M⊙) ≳ 10.5 - over the redshift range 0.5 < z < 2 by use of observer-frame optical and near-infrared slitless spectra from Hubble Space Telescope's ACS and WFC3 grisms. The deep exposures (∼100 ks) allow us to ta…
SLUG IV: a novel forward-modelling method to derive the demographics of star clusters
Calzetti, Daniela; Fumagalli, Michele; Adamo, Angela +1 more
We describe a novel method for determining the demographics of a population of star clusters, for example distributions of cluster mass and age, from unresolved photometry. This method has a number of desirable properties: it fully exploits all the information available in a data set without any binning, correctly accounts for both measurement err…
Discovery of a diffuse optical line emitting halo in the core of the Centaurus cluster of galaxies: line emission outside the protection of the filaments
Fabian, A. C.; Combes, F.; Salomé, P. +6 more
We present the discovery of diffuse optical line emission in the Centaurus cluster seen with the MUSE (Multi Unit Spectroscopic Explorer) integral field unit. The unparalleled sensitivity of MUSE allows us to detect the faint emission from these structures which extend well beyond the bounds of the previously known filaments. Diffuse structures (e…
Towards an informed quest for accretion disc winds in quasars: the intriguing case of Ton 28
Nardini, E.; Lusso, E.; Bisogni, S.
We report on the detection of a blueshifted Fe K absorption feature in two consecutive XMM-Newton observations of the luminous blue quasar Ton 28, at the 4σ cumulative significance. The rest energy of 9.2 keV implies the presence of an accretion disc wind with bulk outflow velocity of ∼0.28c, while the kinetic power is most likely a few per cent o…
Formation of disc galaxies around z ∼ 2
Sachdeva, Sonali; Gogoi, Rupjyoti; Saha, Kanak +2 more
We present combined evolution of morphological and stellar properties of galaxies on the two sides of z = 2 (2.0 < z < 4.0 and 1.5 < z < 2.0) in CDFS, with ground-based spectroscopic redshifts. We perform bulge-disc decomposition on their images in J and H filters, from the 3DHST Legacy Survey obtained using HST/WFC3. Combining morphol…
Investigation of the globular cluster NGC 2808 with the Ultra-Violet Imaging Telescope
Vig, S.; Ghosh, S. K.; Jain, Rashi
Globular clusters represent stellar laboratories where observations can be used to validate models of stellar evolution. In this study, we put forth new ultraviolet (UV) photometric results of stars in the Galactic globular cluster NGC 2808. NGC 2808 is known to host multiple stellar populations that include at least four distinct groups of horizo…
Investigating the origin of the faint non-thermal emission of the Arches cluster using the 2015-2016 NuSTAR and XMM-Newton X-ray observations
Mori, Kaya; Zhang, Shuo; Tomsick, John +7 more
Recent NuSTAR and XMM-Newton observations of the molecular cloud around the Arches stellar cluster demonstrate a dramatic change both in morphology and intensity of its non-thermal X-ray emission, similar to that observed in many molecular clouds of the Central Molecular Zone at the Galactic Center. These variations trace the propagation of illumi…
Multiwavelength spectroscopy of the black hole candidate MAXI J1813-095 during its discovery outburst
De Marco, B.; Armas Padilla, M.; Jiménez-Ibarra, F. +5 more
MAXI J1813-095 is an X-ray transient discovered during an outburst in 2018. We report on X-ray and optical observations obtained during this event, which indicate that the source is a new low-mass X-ray binary. The outburst lasted ∼70 d and peaked at LX(0.5-10 keV) ∼ 7.6 × 1036 erg s-1, assuming a distance of 8 kpc…
T Tauri stars in the SuperWASP and NSVS surveys
Paunzen, E.; Smalley, B.; Vaňko, M. +1 more
We present a study of the long-term optical variability of young T Tauri stars using previously unpublished data from the Super-Wide Angle Search for Planets (SuperWASP) project. Other publicly available photometry from the Northern Sky Variability Survey (NSVS) and the National Aeronautics and Space Administration (NASA) K2 mission were used to c…