Search Publications
The Local Group's mass: probably no more than the sum of its parts
Johansson, Peter H.; Sawala, Till; Teeriaho, Meri
The total mass of the Local Group and the masses of its primary constituents, the Milky Way (MW) and M31, are important anchors for several cosmological questions. Recent independent measurements have consistently yielded halo masses close to 1012M⊙ for the MW, and 1-2 × 1012M⊙ for M31, while estimates d…
ATOMS: ALMA three-millimeter observations of massive star-forming regions - XIII. Ongoing triggered star formation within clump-fed scenario found in the massive ( 1500 M⨀) clump
Tej, Anandmayee; Lee, Chang Won; Liu, Tie +16 more
Whether ionization feedback triggers the formation of massive stars is highly debated. Using ALMA 3-mm observations with a spatial resolution of ~0.05 pc and a mass sensitivity of 1.1 $\rm M_\odot$ per beam at 20 K, we investigate the star formation and gas flow structures within the ionizing feedback-driven structure, a clump-scale massive (≳ 150…
7Be detection in the 2021 outburst of RS Oph
Della Valle, M.; Bonifacio, P.; Hernanz, M. +7 more
The recurrent nova RS Oph underwent a new outburst on 2021 August 8, reaching a visible brightness of V = 4.8 mag. Observations of the 2021 outburst made with the high-resolution UVES spectrograph at the Kueyen-UT2 telescope at ESO-VLT in Paranal enabled detection of the possible presence of 7Be newly made in the thermonuclear runaway r…
The unseen host galaxy and high dispersion measure of a precisely localized fast radio burst suggests a high-redshift origin
Prochaska, J. Xavier; Ryder, Stuart D.; Tejos, Nicolas +13 more
FRB 20210912A is a fast radio burst (FRB), detected and localized to subarcsecond precision by the Australian Square Kilometre Array Pathfinder. No host galaxy has been identified for this burst despite the high precision of its localization and deep optical and infrared follow-up, to 5σ limits of R = 26.7 mag and Ks = 24.9 mag with the…
VLBI Observations of a sample of Palomar-Green quasars II: characterizing the parsec-scale radio emission
Ho, Luis C.; An, Tao; Baan, Willem A. +4 more
This study uses multifrequency very long baseline interferometry (VLBI) to study the radio emission from 10 radio-quiet quasars (RQQs) and four radio-loud quasars (RLQs). The diverse morphologies, radio spectra, and brightness temperatures observed in the VLBI images of these RQQs, together with the variability in their GHz spectra and VLBI flux d…
Galaxy and mass assembly (GAMA): comparing visually and spectroscopically identified galaxy merger samples
Holwerda, Benne; De Propris, Roberto; Brough, Sarah +3 more
We conduct a comparison of the merging galaxy populations detected by a sample of visual identification of tidal features around galaxies as well as spectroscopically detected close pairs of galaxies to determine whether our method of selecting merging galaxies biases our understanding of galaxy interactions. Our volume-limited parent sample consi…
AFGL 5180 and AFGL 6366S: sites of hub-filament systems at the opposite edges of a filamentary cloud
Dewangan, L. K.; Ojha, D. K.; Pandey, Rakesh +3 more
We present a multiscale and multiwavelength study to unveil massive star formation (MSF) processes around sites AFGL 5180 and AFGL 6366S, both hosting a Class II 6.7 GHz methanol maser emission. The radio continuum map at 8.46 GHz reveals a small cluster of radio sources towards AFGL 5180. Signatures of the early stages of MSF in our target sites …
Spectrophotometric analysis of magnetic white dwarf - II. Helium-rich compositions
Dufour, Patrick; Jordan, Stefan; Hardy, François
We present an analysis of all single white dwarf stars known to exhibit spectroscopic signatures of neutral helium line splitting due to the presence of a strong magnetic field. Using state-of-the-art models taking into account the effects of magnetic fields on the synthetic spectra, we determine effective temperatures, surface gravities, and mass…
The Tucana dwarf spheroidal: a distant backsplash galaxy of M31?
Navarro, Julio F.; McConnachie, Alan; Santos-Santos, Isabel M. E.
We use the APOSTLE Local Group (LG) cosmological hydrosimulations to examine the properties of 'backsplash' galaxies, i.e. dwarfs that were within the virial boundaries of the Milky Way (MW) or M31 in the past, but are today outside their virial radius (r200). More than half of all dwarfs between $1\text{ and }2\, r_{200}$ of each prima…
Magnetically activated accretion outbursts of pre-main-sequence discs
Bae, Jaehan; Hartmann, Lee; Cleaver, Jacob
We investigate whether triggering of the magnetorotational instability (MRI) in protoplanetary discs can account for the wide diversity of observed accretion outbursts. We show that short-lived, relatively low accretion rate events probably result from triggering in the inner disc and can occur at low surface densities, comparable to or smaller th…