Search Publications
FORCAST Imaging of Two Small Nearby Clusters: The Coronet and B 59
Vacca, William D.; Reipurth, Bo; Sandell, Göran +1 more
We present mid-infrared imaging of two young clusters, the Coronet in the CrA cloud core and B 59 in the Pipe Nebula, using the FORCAST camera on the Stratospheric Observatory for Infrared Astronomy. We also analyze Herschel Space Observatory4 PACS and SPIRE images of the associated clouds. The two clusters are at similar, and very clos…
Precise Timing and Phase-resolved Spectroscopy of the Young Pulsar J1617-5055 with NuSTAR
Pavlov, George G.; Kargaltsev, Oleg; Hare, Jeremy +2 more
We report on a Nuclear Spectroscopic Telescope Array (NuSTAR) observation of the young, energetic pulsar PSR J1617-5055. Parkes Observatory 3 GHz radio observations of the pulsar (taken about 7 yr before the NuSTAR observations) are also reported here. NuSTAR detected pulsations at a frequency of f ≈ 14.4 Hz (P ≈ 69.44 ms) and, in addition, the ob…
Energy Budget of Plasma Motions, Heating, and Electron Acceleration in a Three-loop Solar Flare
Kontar, Eduard P.; Fleishman, Gregory D.; Nita, Gelu M. +2 more
Nonpotential magnetic energy promptly released in solar flares is converted to other forms of energy. This may include nonthermal energy of flare-accelerated particles, thermal energy of heated flaring plasma, and kinetic energy of eruptions, jets, upflows/downflows, and stochastic (turbulent) plasma motions. The processes or parameters governing …
The Dynamic Formation of Pseudostreamers
Antiochos, Spiro K.; Scott, Roger B.; Pontin, David I. +2 more
Streamers and pseudostreamers structure the corona at the largest scales, as seen in both eclipse and coronagraph white-light images. Their inverted-goblet appearance encloses broad coronal loops at the Sun and tapers to a narrow radial stalk away from the star. The streamer associated with the global solar dipole magnetic field is long-lived, pre…
Study of the Inner Structure of the Molecular Torus in IRAS 08572+3915 NW with Velocity Decomposition of CO Rovibrational Absorption Lines
Onishi, Shusuke; Nakagawa, Takao; Baba, Shunsuke +6 more
Understanding the inner structure of the clumpy molecular torus surrounding the active galactic nucleus is essential in revealing the forming mechanism. However, spatially resolving the torus is difficult because of its size of a few parsecs. Thus, to probe the clump conditions in the torus, we performed the velocity decomposition of the CO rovibr…
Interferometric Imaging of λ Andromedae: Evidence of Starspots and Rotation
White, R. J.; Baron, F.; Parks, J. R. +14 more
Presented are the first interferometric images of cool starspots on the chromospherically active giant λ Andromedae. Using the Michigan Infra-Red Combiner coupled to the Center for High Angular Resolution Astronomy Array, 26 interferometric observations were made between 2008 August 17 and 2011 September 24. The photometric time series acquired at…
On the Nature of Propagating Intensity Disturbances in Polar Plumes during the 2017 Total Solar Eclipse
Madjarska, Maria S.; Lim, Eun-Kyung; Yang, Heesu +8 more
The propagating intensity disturbances (PIDs) in plumes are still poorly understood, and their identity (magnetoacoustic waves or flows) remains an open question. We investigate PIDs in five plumes located in the northern polar coronal hole observed during the 2017 total solar eclipse. Three plumes are associated with coronal bright points, jets, …
Discovery of a Wind-blown Bubble Associated with the Supernova Remnant G346.6-0.2: A Hint for the Origin of Recombining Plasma
Filipović, M. D.; Suzuki, H.; Fukui, Y. +3 more
We report on CO and H I studies of the mixed-morphology supernova remnant (SNR) G346.6-0.2. We find a wind-blown bubble along the radio continuum shell with an expansion velocity of ~10 km s-1, which was likely formed by strong stellar winds from the high-mass progenitor of the SNR. The radial velocities of the CO/H I bubbles at V …
Born in a Pair (?): Pisces II and Pegasus III
Garofalo, Alessia; Calura, Francesco; Paris, Diego +5 more
We have used B, V time-series photometry collected with the Large Binocular Telescope to undertake the first study of variable stars in the Milky Way ultra-faint dwarf (UFD) satellites Pisces II and Pegasus III. In Pisces II we have identified an RRab star, one confirmed and a candidate SX Phoenicis star, and a variable with uncertain classificati…
EvryFlare. IV. Detection of Periodicity in Flare Occurrence from Cool Stars with TESS
Law, Nicholas M.; Howard, Ward S.
Phased flaring, or the periodic occurrence of stellar flares, may probe electromagnetic star-planet interaction (SPI), binary interaction, or magnetic conditions in spots. For the first time, we explore flare periodograms for a large sample of flare stars to identify periodicity due to magnetic interactions with orbiting companions, magnetic reser…