Search Publications
The Spiral Arm Segments of the Galaxy within 3 kpc from the Sun: A Statistical Approach
Hou, Li-Gang; Jiang, Ing-Guey; Griv, Evgeny
As can be reasonably expected, upcoming large-scale APOGEE, GAIA, GALAH, LAMOST, and WEAVE stellar spectroscopic surveys will yield rather noisy Galactic distributions of stars. In view of the possibility of employing these surveys, our aim is to present a statistical method to extract information about the spiral structure of the Galaxy from curr…
The Circumgalactic Medium of Submillimeter Galaxies. II. Unobscured QSOs within Dusty Starbursts and QSO Sightlines with Impact Parameters below 100 kpc
Casey, Caitlin M.; Prochaska, J. Xavier; Scoville, Nick +4 more
We present Atacama Large Millimeter/submillimeter Array (ALMA) 870 µm observations of 29 bright Herschel sources near high-redshift QSOs. The observations confirm that 20 of the Herschel sources are submillimeter-bright galaxies (SMGs) and identify 16 new SMG-QSO pairs that are useful to studies of the circumgalactic medium (CGM) of SMGs. Ei…
An XMM-Newton Study of the Mixed-morphology Supernova Remnant G346.6-0.2
Auchettl, Katie; Slane, Patrick; Ng, C. -Y. +2 more
We present an X-ray imaging and spectroscopic study of the molecular cloud interacting mixed-morphology supernova remnant G346.6-0.2 using XMM-Newton. The X-ray spectrum of the remnant is well described by a recombining plasma that most likely arises from adiabatic cooling and has subsolar abundances of Mg, Si, and S. Our fits also suggest the pre…
Optical Properties of Non-stoichiometric Amorphous Silicates with Application to Circumstellar Dust Extinction
Tamanai, Akemi; Pucci, Annemarie; Dohmen, Ralf +1 more
We determine the optical constants of non-stoichiometric amorphous magnesium-iron silicates and demonstrate that they can well reproduce the observed mid-infrared emission spectra of evolved stars. Stoichiometric and non-stoichiometric amorphous magnesium-iron silicate films are fabricated by pulsed laser deposition. Transmittance and ellipsometry…
Sparse Bayesian Inference and the Temperature Structure of the Solar Corona
Warren, Harry P.; Byers, Jeff M.; Crump, Nicholas A.
Measuring the temperature structure of the solar atmosphere is critical to understanding how it is heated to high temperatures. Unfortunately, the temperature of the upper atmosphere cannot be observed directly, but must be inferred from spectrally resolved observations of individual emission lines that span a wide range of temperatures. Such obse…
Double Stars and Astrometric Uncertainties in Gaia DR1
Makarov, Valeri V.; Frouard, Julien; Fabricius, Claus
A significant number of double stars with separations up to 2.5 arcsec are present in the Gaia Data Release 1 astrometric catalogs. Limiting our analysis to a well-studied sample of 1124 doubles resolved by Hipparcos, provided with individual Tycho component photometry and cross-matched with the TGAS catalog, we estimate a rate of at least 3% for …
Propagation Characteristics of Two Coronal Mass Ejections from the Sun Far into Interplanetary Space
Wang, Rui; Liu, Ying D.; Hu, Huidong +1 more
Propagation of coronal mass ejections (CMEs) from the Sun far into interplanetary space is not well understood, due to limited observations. In this study we examine the propagation characteristics of two geo-effective CMEs, which occurred on 2005 May 6 and 13, respectively. Significant heliospheric consequences associated with the two CMEs are ob…
Tethered Prominence-CME Systems Captured during the 2012 November 13 and 2013 November 3 Total Solar Eclipses
Habbal, Shadia R.; Druckmüller, Miloslav; Alzate, Nathalia +1 more
We report on white light observations of high latitude tethered prominences acquired during the total solar eclipses of 2012 November 13 and 2013 November 3, at solar maximum, with a field of view spanning several solar radii. Distinguished by their pinkish hue, characteristic of emission from neutral hydrogen and helium, the four tethered promine…
An Evolving GeV Spectrum from Prompt to Afterglow: The Case of GRB 160509A
Tang, Qing-Wen; Wang, Xiang-Yu; Tam, Pak-Hin Thomas +1 more
We present the high-energy emission properties of GRB 160509A, from its prompt mission to late afterglow phase. GRB 160509A contains two emission episodes: 0-40 s and 280-420 s after the burst onset ({t}0). The relatively high fluence of GRB 160509A allows us to establish an evolving spectrum above 100 MeV. During the first emission epi…
Long-term Spectral Variability of the Ultraluminous X-Ray Source Holmberg IX X-1
Jithesh, V.; Wang, Zhongxiang; Misra, Ranjeev
We investigate the long-term spectral variability in the ultraluminous X-ray source Holmberg IX X-1. By analyzing the data from 8 Suzaku and 13 XMM-Newton observations conducted between 2001 and 2015, we perform a detailed spectral modeling for all spectra with simple models and complex physical models. We find that the spectra can be well explain…