Search Publications
A Double-modulation Effect Detected in a Double-mode High-amplitude δ Scuti Star: KIC 10284901
Esamdin, Ali; Yang, Tao-Zhi
In this paper, we present an analysis of the pulsating behavior of Kepler target KIC 10284901. The Fourier transform of the high-precision light curve reveals seven independent frequencies for its light variations. Among them, the first two frequencies are main pulsation modes: F0 = 18.994054(1) day-1 and F1 = 24.335804(4) day-1
UV to X-Ray Comptonization Delay in Mrk 493
Dewangan, Gulab C.; Pal, Main; Pawar, Pramod +1 more
The broadband X-ray emission from type 1 active galactic nuclei, dominated by a power-law continuum, is thought to arise from repeated inverse Compton scattering of seed optical/UV photons by energetic electrons in a hot corona. The seed optical/UV photons are assumed to arise from an accretion disk, but direct observational evidence has remained …
First Evidence of Enhanced Recombination in Astrophysical Environments and the Implications for Plasma Diagnostics
Dupree, A. K.; Raymond, J.; García-Rojas, J. +6 more
We report the first unambiguous observational evidence of Rydberg Enhanced Recombination (RER), a potentially important recombination mechanism that has hitherto been unexplored in low-temperature photoionized plasmas. RER shares similarities with dielectronic recombination, with the difference that the electron is captured into a highly excited s…
On the Fast Solar Wind Heating and Acceleration Processes: A Statistical Study Based on the UVCS Survey Data
Telloni, Daniele; Antonucci, Ester; Giordano, Silvio
The UltraViolet Coronagraph Spectrometer (UVCS) on board the SOlar and Heliospheric Observatory has almost continuously observed, throughout the whole solar cycle 23, the UV solar corona. This work addresses the first-ever statistical analysis of the daily UVCS observations, performed in the O VI channel, of the northern polar coronal hole, betwee…
Large Molecular Gas Reservoirs in Star-forming Cluster Galaxies
Mroczkowski, Tony; De Breuck, Carlos; Stroe, Andra +2 more
We present CO (2-1) observations of 72 galaxies in the nearby, disturbed Antlia Cluster with the Atacama Pathfinder Experiment telescope. The galaxies in our sample are selected to span a wide range of stellar masses (108 M ⊙ ≲ M ⋆ ≲ 1010 M ⊙) and star formation rates (0.0005 M ⊙ yr…
Molecular Gas Properties in the Host Galaxy of GRB 080207
Hashimoto, Tetsuya; Tamura, Yoichi; Kohno, Kotaro +5 more
We present the results of CO(1-0) and CO(4-3) observations of the host galaxy of a long-duration gamma-ray burst GRB 080207 at z = 2.0858 by using the Karl G. Jansky Very Large Array and the Atacama Large Millimeter/submillimeter Array. The host is detected in CO(1-0) and CO(4-3), becoming the first case for a gamma-ray burst (GRB) host with more …
Strong Gravitational Lensing by Wave Dark Matter Halos
Gonzalez-Morales, Alma X.; Herrera-Martín, Antonio; Hendry, Martin +1 more
Wave dark matter (WaveDM) has recently gained attention as a viable candidate to account for the dark matter content of the universe. In this paper we explore the extent to which, and under what conditions, dark matter halos in this model are able to reproduce strong-lensing systems. First, we explore analytically the lensing properties of the mod…
Studying the Evolution of Warm Dust Encircling BD +20 307 Using SOFIA
Stark, Christopher C.; Weinberger, Alycia J.; Thompson, Maggie A. +2 more
The small class of known stars with unusually warm, dusty debris disks is a key sample to probe in order to understand cascade models and the extreme collisions that likely lead to the final configurations of planetary systems. Because of its extreme dustiness and small radius, the disk of BD +20 307 has a short predicted collision time and is the…
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…
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…