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Blueshifted absorption lines from X-ray reflection in IRAS 13224-3809
Young, A. J.; Fabian, A. C.; Miller, J. M. +17 more
We explore a disc origin for the highly blueshifted, variable absorption lines seen in the X-ray spectrum of the narrow-line Seyfert 1 galaxy IRAS 13224-3809. The blueshift corresponds to a velocity of ∼0.25c. Such features in other active galactic nuclei are often interpreted as ultrafast outflows. The velocity is of course present in the orbital…
A Gas Giant Planet in the OGLE-2006-BLG-284L Stellar Binary System
Udalski, Andrzej; Mróz, Przemek; Szymański, Michał K. +34 more
We present the analysis of microlensing event OGLE-2006-BLG-284, which has a lens system that consists of two stars and a gas giant planet with a mass ratio of qp = (1.26 ± 0.19) × 10-3 to the primary. The mass ratio of the two stars is qs = 0.289 ± 0.011, and their projected separation is ss = 2.1 ± 0.7…
Discovery of a complex spiral-shell structure around the oxygen-rich AGB star GX Monocerotis
Wittkowski, M.; Kim, H.; Randall, S. K. +4 more
The circumstellar envelopes of asymptotic giant branch (AGB) stars exhibit a wide range of morphologies and chemical compositions that can be exploited to unravel their mass-loss history as well as binary status. Here, we present ALMA Band 6 observations centred upon the oxygen-rich, high mass-loss rate AGB star GX Mon. The resulting CO (2-1) map …
The residence-time of Jovian electrons in the inner heliosphere
Heber, B.; Herbst, K.; Vogt, A. +3 more
Context. Jovian electrons serve an important role in test-particle distribution in the inner heliosphere. They have been used extensively in the past to study the (diffusive) transport of cosmic rays in the inner heliosphere. With new limits on the Jovian source function, that is, the particle intensity just outside the Jovian magnetosphere, and a…
Variability in the Massive Open Cluster NGC 1817 from K2: A Rich Population of Asteroseismic Red Clump, Eclipsing Binary, and Main-sequence Pulsating Stars
Vanderburg, Andrew; Stello, Dennis; Grundahl, Frank +13 more
We present a survey of variable stars detected in K2 Campaign 13 within the massive intermediate-age (∼1 Gyr) open cluster NGC 1817. We identify a complete sample of 44 red clump stars in the cluster, and have measured asteroseismic quantities (νmax and/or Δν) for 29 of them. Five stars showed suppressed dipole modes, and the occurrence…
Chandra Observations of High-energy X-Ray Sources Discovered by INTEGRAL
Hare, Jeremy; Rahoui, Farid; Fornasini, Francesca M. +6 more
The International Gamma-Ray Astrophysics Laboratory (INTEGRAL) satellite has detected in excess of 1000 sources in the ∼20-100 keV band during its surveys of the sky over the past 17 years. We obtained 5 ks observations of 15 unclassified INTEGRAL Gamma-Ray (IGR) sources with the Chandra X-ray Observatory in order to localize them, to identify opt…
Vilnius photometry and Gaia astrometry of Melotte 105
Bilir, Selçuk; Yontan, Talar; Canbay, Remziye +1 more
Archival Vilnius CCD photometric observations are presented for the heavily reddened star cluster Melotte 105, resulting in colour-magnitude diagrams and spectral class estimates. There is considerable lack of agreement between studies for reddening, age and distance for this cluster explaining why the archival data are being made available by thi…
V363 Cassiopeiae: a new lithium-rich Galactic Cepheid
Clementini, G.; Ripepi, V.; Molinaro, R. +8 more
Context. Classical Cepheids (DCEPs) are important astrophysical objects not only as standard candles in the determination of the cosmic distance ladder, but also as a testbed for the stellar evolution theory. This is based on the strict connection between their pulsation (period(s) and amplitudes) and stellar parameters (luminosity, mass, effectiv…
Local Molecular Gas toward the Aquila Rift Region
Chen, Zhiwei; Wang, Hongchi; Gong, Yan +11 more
We present the results of a ∼250 square degrees CO mapping (+26° ≲ l ≲ +50° and -5° ≲ b ≲ +5°) toward the Aquila Rift region at a spatial resolution of ∼50″ and a grid spacing of 30″. The high dynamic range CO maps with a spectral resolution of ∼0.2 km s-1 display highly structured molecular cloud (MC) morphologies with valuable velocit…
The Supernova Remnant Population of NGC 6946 as Observed in [Fe II] 1.644 µm with HST
Blair, William P.; Long, Knox S.; Winkler, P. Frank +1 more
NGC 6946 is a high-star-formation-rate, face-on, spiral galaxy that has hosted 10 supernovae since 1917. Not surprisingly, a large number of supernova remnants and candidates have been identified either as optical nebulae with high [S II]:Hα line ratios (147) or as compact non-thermal radio sources (35). However, there are only seven overlaps betw…