Search Publications
Measuring the Magnetic Field of Young Stars Using iSHELL Observations: BP Tau and V347 Aur
Flores, C.; Boogert, A.; Connelley, M. S. +1 more
While it has been suggested that there is a connection between the magnetic properties and the internal structure of young stars, there have not been enough magnetic measurements to firmly establish such a correlation at the earliest ages. Here, we contribute to this endeavor by presenting stellar parameters and magnetic field strength measurement…
Hubble Space Telescope analysis of stellar populations within the globular cluster G1 (Mayall II) in M 31
Milone, A. P.; Bedin, L. R.; Rich, R. M. +5 more
In this paper, we present a multiwavelength analysis of the complex stellar populations within the massive globular cluster Mayall II (G1), a satellite of the nearby Andromeda galaxy projected at a distance of 40 kpc. We used images collected with the Hubble Space Telescope in UV, blue and optical filters to explore the multiple stellar population…
Flipping-up the field: gravitational feedback as a mechanism for young clusters dispersal
Kounkel, Marina; Hernández, Jesús; Román-Zúñiga, Carlos +3 more
Recent analyses of Gaia data have provided direct evidence that most young stellar clusters are in a state of expansion, with velocities of the order of ∼0.5 km s-1. Traditionally, expanding young clusters have been pictured as entities that became unbound due to the lack of gravitational binding once the gas from the parental cloud tha…
The New EXor Outburst of ESO-Hα 99 Observed by Gaia ATLAS and TESS
Kochanek, C. S.; Tonry, John; Vallely, Patrick J. +11 more
We report photometry and spectroscopy of the outburst of the young stellar object ESO-Hα99. The outburst was first noticed in Gaia alert Gaia18dvc and later by the Asteroid Terrestrial-impact Last Alert System (ATLAS). We have established the outburst light curve with archival ATLAS orange filter photometry, Gaia data, new V-band photometry, and J…
A connection between accretion states and the formation of ultrarelativistic outflows in a neutron star X-ray binary
Motta, S. E.; Fender, R. P.
The nearby accreting neutron star binary Sco X-1 is the closest example of ongoing relativistic jet production at high Eddington ratios. Previous radio studies have revealed that alongside mildly relativistic, radio-emitting ejecta, there is at times a much faster transfer of energy from the region of the accretion flow along the jet. The nature o…
The seventh inner moon of Neptune
Showalter, M. R.; de Pater, I.; Lissauer, J. J. +1 more
During its 1989 flyby, the Voyager 2 spacecraft imaged six small moons of Neptune, all with orbits well interior to that of the large, retrograde moon Triton1. Along with a set of nearby rings, these moons are probably younger than Neptune itself; they formed shortly after the capture of Triton and most of them have probably been fragme…
Broadband Spectral Energy Distributions of SDSS-selected Quasars and of Their Host Galaxies: Intense Activity at the Onset of AGN Feedback
Lapi, Andrea; Gilli, Roberto; Baccigalupi, Carlo +3 more
We present the mean spectral energy distribution (SED) of a sample of optically selected quasars (QSOs) at redshifts of 1 ≤ z ≤ 5. To derive it, we exploit photometric information from the Sloan Digital Sky Survey, UKIRT Infrared Deep Sky Survey, and Wide-field Infrared Survey Explorer surveys in combination with a stacking analysis of Herschel, A…
Multiband Galaxy Morphologies for CLASH: A Convolutional Neural Network Transferred from CANDELS
Demarco, R.; Huertas-Company, M.; Cabrera-Vives, G. +5 more
We present visual-like morphologies over 16 photometric bands, from ultraviolet to near-infrared, for 8412 galaxies in the Cluster Lensing And Supernova survey with Hubble (CLASH) obtained using a convolutional neural network (ConvNet) model. Our model follows the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) main morphologica…
Measuring the ionisation fraction in a jet from a massive protostar
Sanna, A.; Purser, S. J. D.; Ray, T. P. +7 more
It is important to determine if massive stars form via disc accretion, like their low-mass counterparts. Theory and observation indicate that protostellar jets are a natural consequence of accretion discs and are likely to be crucial for removing angular momentum during the collapse. However, massive protostars are typically rarer, more distant an…
Star Formation Histories of the LEGUS Spiral Galaxies. I. The Flocculent Spiral NGC 7793
Cignoni, M.; Tosi, M.; Sabbi, E. +13 more
We present a detailed study of the flocculent spiral galaxy NGC 7793, part of the Sculptor group. By analyzing the resolved stellar populations of the galaxy, located at a distance of ∼3.7 Mpc, we infer for the first time its radial star formation history (SFH) from Hubble Space Telescope photometry, thanks to both archival and new data from the L…