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Orbital Motion, Variability, and Masses in the T Tauri Triple System

Prato, L.; Schaefer, G. H.; Beck, Tracy L. +1 more

We present results from adaptive optics imaging of the T Tauri triple system obtained at the Keck and Gemini Observatories in 2015-2019. We fit the orbital motion of T Tau Sb relative to Sa and model the astrometric motion of their center of mass relative to T Tau N. Using the distance measured by Gaia, we derived dynamical masses of ${M}_{\mathrm…

Multiband Probabilistic Cataloging: A Joint Fitting Approach to Point-source Detection and Deblending

Finkbeiner, Douglas; Daylan, Tansu; Portillo, Stephen K. N. +1 more

Probabilistic cataloging (PCAT) outperforms traditional cataloging methods on single-band optical data in crowded fields. We extend our work to multiple bands, achieving greater sensitivity (∼0.4 mag) and greater speed (500×) compared to previous single-band results. We demonstrate the effectiveness of multiband PCAT on mock data, in terms of both…

PKS 2250-351: A giant radio galaxy in Abell 3936

Seymour, N.; Leahy, D. A.; Norris, R. P. +27 more

We present a detailed analysis of the radio galaxy PKS $2250{-}351$ , a giant of 1.2 Mpc projected size, its host galaxy, and its environment. We use radio data from the Murchison Widefield Array, the upgraded Giant Metre-wavelength Radio Telescope, the Australian Square Kilometre Array Pathfinder, and the Australia Telescope Compact Array to mode…

Three-dimensional reconstruction of multiple particle acceleration regions during a coronal mass ejection

Palmerio, E.; Vainio, R.; Kilpua, E. K. J. +3 more

Context. Some of the most prominent sources for particle acceleration in our Solar System are large eruptions of magnetised plasma from the Sun called coronal mass ejections (CMEs). These accelerated particles can generate radio emission through various mechanisms.
Aims: CMEs are often accompanied by a variety of solar radio bursts with diffe…

The various accretion modes of AM Herculis: Clues from multi-wavelength observations in high accretion states

Sablowski, D.; Schwope, A. D.; Traulsen, I. +1 more

We report on XMM-Newton and NuSTAR X-ray observations of the prototypical polar, AM Herculis, supported by ground-based photometry and spectroscopy, all obtained in high accretion states. In 2005, AM Herculis was in its regular mode of accretion, showing a self-eclipse of the main accreting pole. X-ray emission during the self-eclipse was assigned…

Photometric rotation periods for 107 M dwarfs from the APACHE survey

Sozzetti, A.; Giacobbe, P.; Lattanzi, M. G. +13 more

We present rotation period measurements for 107 M dwarfs in the mass range 0.15-0.70 M_⊙ observed within the context of the APACHE photometric survey. We measure rotation periods in the range 0.5-190 d, with the distribution peaking at ∼30 d. We revise the stellar masses and radii for our sample of rotators by exploiting the Gaia DR2 data. For ∼20…

Determining the Bulk Parameters of Plasma Electrons from Pitch-Angle Distribution Measurements

Verscharen, Daniel; Livadiotis, George; Owen, Christopher +3 more

First Images of the Protoplanetary Disk around PDS 201

Dong, Ruobing; Wagner, Kevin; Stone, Jordan +11 more

Scattered light imaging has revealed nearly a dozen circumstellar disks around young Herbig Ae/Be stars—enabling studies of structures in the upper disk layers as potential signs of ongoing planet formation. We present the first images of the disk around the variable Herbig Ae star PDS 201 (V* V351 Ori) and an analysis of the images and spectral e…

VLA and ALMA observations of the lensed radio-quiet quasar SDSS J0924+0219: a molecular structure in a 3 µJy radio source

Sluse, Dominique; Jackson, Neal; Stacey, Hannah +3 more

We present Karl G. Jansky Very Large Array (VLA) and Atacama Large Millimetre Array (ALMA) observations of SDSS J0924+0219, a z = 1.524 radio-quiet lensed quasar with an intrinsic radio flux density of about 3 $\, \mu$ Jy. The four lensed images are clearly detected in the radio continuum and the CO(5-4) line, whose centroid is at z = 1.5254 ± 0.0…

The dynamical state of Abell 2399: a bullet-like cluster

Moretti, A.; Vulcani, B.; Lopes, P. A. A. +8 more

While there are many ways to identify substructures in galaxy clusters using different wavelengths, each technique has its own caveat. In this paper, we conduct a detailed substructure search and dynamical state characterization of Abell 2399, a galaxy cluster in the local Universe (z ~ 0.0579), by performing a multiwavelength analysis and testing…