Search Publications
What information can we derive from historical Far Eastern guest stars for modern research on novae and cataclysmic variables?
Hoffmann, Susanne M.
Recently, there have been several studies on the evolution of binary systems using historical data that are treated as facts in the chain of argument. This paper discusses six case studies of modern dwarf novae with suggested historical counterparts from the historical point of view, as well as the derived consequences for the physics of close bin…
The study of unclassified B[e] stars and candidates in the Galaxy and Magellanic Clouds†
Borges Fernandes, M.; Condori, C. A. H.; Kraus, M. +2 more
We investigated 12 unclassified B[e] stars or candidates, 8 from the Galaxy, 2 from the Large Magellanic Cloud (LMC), and 2 from the Small Magellanic Cloud (SMC). Based on the analysis of high-resolution spectroscopic (FEROS) and photometric data, we confirmed the presence of the B[e] phenomenon for all objects of our sample, except for one (IRAS …
Thermal Emission in the Southwest Clump of VY CMa
Humphreys, Roberta M.; Stone, Jordan; Ertel, Steve +6 more
We present high spatial resolution LBTI/NOMIC 9-12 µm images of VY CMa and its massive outflow feature, the Southwest (SW) Clump. Combined with high-resolution imaging from the Hubble Space Telescope (0.4-1 µm) and LBT/LMIRCam (1-5µm), we isolate the spectral energy distribution (SED) of the clump from the star itself. Using radi…
Testing Efficiency of Empirical, Adaptive, and Global MHD Magnetospheric Models to Represent the Geomagnetic Field in a Variety of Conditions
Sergeev, V. A.; Zheng, Y.; Tsyganenko, N. A. +1 more
We used data for eight magnetospheric spacecraft providing magnetic observations in various magnetospheric domains during a six-day time period, including the June 2015 storm, and a five-day period including the March 2015 storm. For these time intervals, containing different solar wind regimes and different activity levels, we used three types of…
Measurements of the Cross-spectra of the Cosmic Infrared and Microwave Backgrounds from 95 to 1200 GHz
Bock, J.; Bleem, L. E.; Stark, A. A. +40 more
We present measurements of the power spectra of cosmic infrared background (CIB) and cosmic microwave background (CMB) fluctuations in six frequency bands. Maps at the lower three frequency bands, 95, 150, and 220 GHz (3330, 2000, and 1360 µm) are from the South Pole Telescope, while the upper three frequency bands, 600, 857, and 1200 GHz (5…
Solar wind charge exchange in cometary atmospheres. II. Analytical model
Alho, Markku; Simon Wedlund, Cyril; Nilsson, Hans +7 more
Context. Solar wind charge-changing reactions are of paramount importance to the physico-chemistry of the atmosphere of a comet because they mass-load the solar wind through an effective conversion of fast, light solar wind ions into slow, heavy cometary ions. The ESA/Rosetta mission to comet 67P/Churyumov-Gerasimenko (67P) provided a unique oppor…
The 2L1S/1L2S Degeneracy for Two Microlensing Planet Candidates Discovered by the KMTNet Survey in 2017
Kim, S. -L.; Lee, C. -U.; Bennett, D. P. +49 more
We report two microlensing planet candidates discovered by the Korea Microlensing Telescope Network (KMTNet) survey in 2017. However, both events have the 2L1S/1L2S degeneracy, which is an obstacle to claiming the discovery of the planets with certainty unless the degeneracy can be resolved. For KMT-2017-BLG-0962, the degeneracy cannot be resolved…
A Massive Magnetic Helium Atmosphere White Dwarf Binary in a Young Star Cluster
Dufour, Patrick; Bergeron, Pierre; Caiazzo, Ilaria +4 more
We have searched the Gaia DR2 catalog for previously unknown hot white dwarfs in the direction of young open star clusters. The aim of this experiment was to try and extend the initial-final mass relation (IFMR) to somewhat higher masses, potentially challenging the Chandrasekhar limit currently thought to be around 1.38 M ⊙. We discove…
A DECam view of the diffuse dwarf galaxy Crater II: the colour-magnitude diagram
Walker, A. R.; Stetson, P. B.; Bono, G. +12 more
We present a deep Blanco/DECam colour-magnitude diagram (CMD) for the large but very diffuse Milky Way satellite dwarf galaxy Crater II. The CMD shows only old stars with a clearly bifurcated subgiant branch (SGB) that feeds a narrow red giant branch. The horizontal branch (HB) shows many RR Lyrae and red HB stars. Comparing the CMD with [Fe/H] = …
Influence of Wolf-Rayet Stars on Surrounding Star-forming Molecular Clouds
Herczeg, Gregory J.; Bhatt, B. C.; Deng, Licai +5 more
We investigate the influence of Wolf-Rayet (W-R) stars on their surrounding star-forming molecular clouds. We study five regions containing W-R stars in the inner Galactic plane (l ∼ [14°-52°]), using multiwavelength data from near-infrared to radio wavelengths. Analysis of 13CO line data reveals that these W-R stars have developed gas-…