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Full-Text Articles in Physical Sciences and Mathematics
Two Portions Of Sagittarius Stream In The Lamost Complete Spectroscopic Survey Of Pointing Area At Southern Galactic Cap, J. K. Zhao, Terry D. Oswalt, X. H. Ye, H. Wu, M. Yang, X. X. Xue, Y. Q. Chen, J. J. Zhan, G. Zhao
Two Portions Of Sagittarius Stream In The Lamost Complete Spectroscopic Survey Of Pointing Area At Southern Galactic Cap, J. K. Zhao, Terry D. Oswalt, X. H. Ye, H. Wu, M. Yang, X. X. Xue, Y. Q. Chen, J. J. Zhan, G. Zhao
Publications
We constructed a sample of 13,798 stars with Teff , log g, [Fe/H], radial velocity, proper motions and parallaxes from LAMOST DR5 and Gaia DR2 in the LAMOST Complete Spectroscopic Survey of Pointing Area (LaCoSSPAr) at the Southern Galactic Cap consisting of areas A and B. Using the distributions in both proper motions and radial velocity, we detected very significant overdensi- ties in these two areas. These substructures most likely are portions of Sagittarius (Sgr) stream. With the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm, 220 candidates stream members were identified. Based upon distance to the Sun and …
The Exotime Project: Signals In The O − C Diagrams Of The Rapidly Pulsating Subdwarfs Dw Lyn, V1636 Ori, Qq Vir, And V541 Hya, F. Mackebrandt, Terry Oswalt, S. Schuh, R. Silvotti, S. -L. Kim, D. Kilkenny, E. M. Green, R. Lutz, T. Nagel, J. L. Provencal, Tomomi Otani, S. Benatti, L. Lanteri, A. Bonanno, A. Frasca, R. Janulis, M. Paparó, L. Molnár, R. Claudi, R. H. Østensen
The Exotime Project: Signals In The O − C Diagrams Of The Rapidly Pulsating Subdwarfs Dw Lyn, V1636 Ori, Qq Vir, And V541 Hya, F. Mackebrandt, Terry Oswalt, S. Schuh, R. Silvotti, S. -L. Kim, D. Kilkenny, E. M. Green, R. Lutz, T. Nagel, J. L. Provencal, Tomomi Otani, S. Benatti, L. Lanteri, A. Bonanno, A. Frasca, R. Janulis, M. Paparó, L. Molnár, R. Claudi, R. H. Østensen
Publications
Aims. We aim to investigate variations in the arrival time of coherent stellar pulsations due to the light-travel time effect to test for the presence of sub-stellar companions. Those companions are the key to one possible formation scenario of apparently single sub-dwarf B stars. Methods. We made use of an extensive set of ground-based observations of the four large amplitude p-mode pulsators DW Lyn, V1636 Ori, QQ Vir, and V541 Hya. Observations of the TESS space telescope are available on two of the targets. The timing method compares the phase of sinusoidal fits to the full multi-epoch light curves with …