Search Publications
A New Candidate Luminous Blue Variable
Menten, Karl M.; Figer, Donald F.; Messineo, Maria +2 more
We identify IRAS 16115-5044, which was previously classified as a protoplanetary nebula (PPN), as a candidate luminous blue variable (LBV). The star has high luminosity (≳105.75 L⊙), ensuring supergiant status, has a temperature similar to LBVs, is photometrically and spectroscopically variable, and is surrounded by warm dust…
Sources of Bipolar Outflows and Model Challenges for the Egg Nebula
Ohyama, Youichi; Lim, Jeremy; Dinh-V-Trung
The striking features of the Egg Nebula—searchlight beams that illuminate a pair of bipolar lobes, quadrupolar outflows, and arcs imprinted on an expanding spherical envelope—have long defied a coherent explanation. Here we present images at high angular resolutions of emission from dust and dense molecular gas in the nebula. Away from the systemi…
Detection Capability of Flux Ropes during the Solar Orbiter Mission
Telloni, Daniele; Zank, Gary P.; Adhikari, Laxman +6 more
Flux ropes are interplanetary magnetic helical structures that are receiving increasing attention because of their likely role in magnetohydrodynamic (MHD) processes as well as their impact on space weather science. A very promising and powerful approach to address their investigation and characterization is based on wavelet spectrograms of the in…
A Radio Molecular Line Search for Evidence of an O-rich Environment Around Binary in Silicate Carbon Stars
Chen, Xi; Ellingsen, Simon P.; Sobolev, Andrej M. +2 more
We report observations of oxygen-rich (O-rich) radio molecular line tracers, including H2CO, H2O, and HCO+ toward 28 silicate carbon stars (SCSs). SCSs are special evolved star systems that consist of a carbon star associated with peculiar O-rich circumstellar material. Absorption in the 6 cm ${{\rm{H}}}_{2}\mathrm…
Radio Signature of a Distant behind-the-limb CME on 2017 September 6
Rucker, H. O.; Panchenko, M.; Konovalenko, A. A. +5 more
We discuss properties of a Type IV burst, which was observed on 2017 September 6, as a result of the powerful flare X 9.3. At decameter wavelengths this burst was observed by the radio telescopes STEREO A, URAN-2, and the Nancay Decameter Array at frequencies 5-35 MHz. This moving Type IV burst was associated with a coronal mass ejection (CME) pro…
ACRONYM IV: Three New, Young, Low-mass Spectroscopic Binaries
Kraus, Adam L.; Shkolnik, Evgenya L.; Bowler, Brendan P. +4 more
As part of our search for new low-mass members of nearby young moving groups (YMGs), we discovered three low-mass, spectroscopic binaries, two of which are not kinematically associated with any known YMG. Using high-resolution optical spectroscopy, we measure the component and systemic radial velocities of the systems, as well as their lithium abs…
Dissecting the Strong-lensing Galaxy Cluster MS 0440.5+0204. I. The Mass Density Profile
Limousin, Marceau; Carrasco, Eleazar R.; de Diego, José A. +5 more
We present a parametric strong-lensing modeling of the galaxy cluster MS 0440.5+0204 (located at z = 0.19). We have performed a strong-lensing mass reconstruction of the cluster using three different models. The first model uses the image positions of four multiply imaged systems (providing 26 constraints). The second one combines strong-lensing c…
On the Formation of Lyman β and the O I 1027 and 1028 Å Spectral Lines
Carlsson, Mats; Shimizu, Toshifumi; Hasegawa, Takahiro +1 more
We study the potential of Lyman β and the O I 1027 and 1028 Å spectral lines to help in understanding the properties of the chromosphere and transition region (TR). The oxygen transitions are located in the wing of Lyman β, which is a candidate spectral line for the solar missions Solar Orbiter/Spectral Imaging of the Coronal Environment and Solar…
Electron Density Reconstruction of Solar Coronal Mass Ejections Based on a Genetic Algorithm: Method and Application
Inhester, Bernd; Wang, Huaning; Dai, Xinghua
We present a new method to reconstruct the three-dimensional electron density of coronal mass ejections (CMEs) based on a genetic algorithm, namely the genetic reconstruction method (GRM). GRM is first applied to model CMEs with different orientations and shapes. A set of analytic model CMEs from Gibson and Low is employed to produce synthetic CME…
Water in the Star-forming Region NGC 7129 FIRS 2
Conrad, Mollie E.; Fich, Michel
Observations of intermediate mass (IM) star formation are expected to highlight the transition between the formation processes of its low and high-mass (HM) counterparts. ${{\rm{H}}}_{2}^{18}{\rm{O}}$ and ${{\rm{H}}}_{2}^{16}{\rm{O}}$ observations of the IM star formation region NGC 7129 FIRS 2 were obtained with the Heterodyne Instrument for the …