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Binary Central Stars of Planetary Nebulae Discovered Through Photometric Variability. V. The Central Stars of HaTr 7 and ESO 330-9
DOI: 10.3847/1538-3881/153/1/24 Bibcode: 2017AJ....153...24H

Frew, David J.; Reindl, Nicole; Margheim, Steve +3 more

We find the central stars (CSs) of the planetary nebulae (PNe) HaTr 7 and ESO 330-9 to be close-binary systems. Both have orbital periods of less than half a day and contain an irradiated cool companion to the hot CS. We provide light curves, spectra, radial velocity curves, orbital periods, and binary modeling results for both systems. The binary…

2017 The Astronomical Journal
Gaia 44
Discovery of Extended Main-sequence Turnoffs in Four Young Massive Clusters in the Magellanic Clouds
DOI: 10.3847/1538-4357/aa7b36 Bibcode: 2017ApJ...844..119L

Milone, Antonino P.; Deng, Licai; de Grijs, Richard +1 more

An increasing number of young massive clusters (YMCs) in the Magellanic Clouds have been found to exhibit bimodal or extended main sequences (MSs) in their color-magnitude diagrams (CMDs). These features are usually interpreted in terms of a coeval stellar population with different stellar rotational rates, where the blue and red MS stars are popu…

2017 The Astrophysical Journal
eHST 44
Space Weather Effects Produced by the Ring Current Particles
DOI: 10.1007/s11214-017-0412-2 Bibcode: 2017SSRv..212.1315G

Jaynes, Allison; Ganushkina, Natalia; Liemohn, Michael

One of the definitions of space weather describes it as the time-varying space environment that may be hazardous to technological systems in space and/or on the ground and/or endanger human health or life. The ring current has its contributions to space weather effects, both in terms of particles, ions and electrons, which constitute it, and magne…

2017 Space Science Reviews
Cluster 44
Multiplicity and clustering in Taurus star-forming region. I. Unexpected ultra-wide pairs of high-order multiplicity in Taurus
DOI: 10.1051/0004-6361/201629398 Bibcode: 2017A&A...599A..14J

Duchêne, Gaspard; Moraux, Estelle; Joncour, Isabelle


Aims: This work analyses the spatial distribution of stars in Taurus with a specific focus on multiple stars and wide pairs in order to derive new constraints on star formation and early dynamical evolution scenarios.
Methods: We collected the multiplicity data of stars in Taurus to build an up-to-date stellar/multiplicity catalog. We fi…

2017 Astronomy and Astrophysics
Gaia 43
An improved age-activity relationship for cool stars older than a gigayear
DOI: 10.1093/mnras/stx1630 Bibcode: 2017MNRAS.471.1012B

Poppenhaeger, K.; Silva Aguirre, V.; Wolk, S. J. +2 more

Stars with convective envelopes display magnetic activity, which decreases over time due to the magnetic braking of the star. This age dependence of magnetic activity is well studied for younger stars, but the nature of this dependence for older stars is not well understood. This is mainly because absolute stellar ages for older stars are hard to …

2017 Monthly Notices of the Royal Astronomical Society
Gaia XMM-Newton 43
Model-independent analyses of non-Gaussianity in Planck CMB maps using Minkowski functionals
DOI: 10.1088/1361-6382/aa5ce2 Bibcode: 2017CQGra..34i4002B

Buchert, Thomas; France, Martin J.; Steiner, Frank

Despite the wealth of Planck results, there are difficulties in disentangling the primordial non-Gaussianity of the Cosmic Microwave Background (CMB) from the secondary and the foreground non-Gaussianity (NG). For each of these forms of NG the lack of complete data introduces model-dependences. Aiming at detecting the NGs of the CMB temperature an…

2017 Classical and Quantum Gravity
Planck 43
Extragalactic background light: a measurement at 400 nm using dark cloud shadow - II. Spectroscopic separation of the dark cloud's light, and results
DOI: 10.1093/mnras/stx1296 Bibcode: 2017MNRAS.470.2152M

Leinert, Ch.; Väisänen, P.; Lehtinen, K. +2 more

In a project aimed at measuring the optical extragalactic background light (EBL), we are using the shadow of a dark cloud. We have performed, with the ESO VLT/FORS, spectrophotometry of the surface brightness towards the high-galactic-latitude dark cloud Lynds 1642. A spectrum representing the difference between the opaque core of the cloud and se…

2017 Monthly Notices of the Royal Astronomical Society
ISO eHST 43
Orbits of massive satellite galaxies - II. Bayesian estimates of the Milky Way and Andromeda masses using high-precision astrometry and cosmological simulations
DOI: 10.1093/mnras/stx698 Bibcode: 2017MNRAS.468.3428P

Besla, Gurtina; Patel, Ekta; Mandel, Kaisey

In the era of high-precision astrometry, space observatories like the Hubble Space Telescope (HST) and Gaia are providing unprecedented 6D phase-space information of satellite galaxies. Such measurements can shed light on the structure and assembly history of the Local Group, but improved statistical methods are needed to use them efficiently. Her…

2017 Monthly Notices of the Royal Astronomical Society
Gaia 43
OCCASO - II. Physical parameters and Fe abundances of red clump stars in 18 open clusters
DOI: 10.1093/mnras/stx1481 Bibcode: 2017MNRAS.470.4363C

Jordi, C.; Casamiquela, L.; Anders, F. +13 more

Open clusters have long been used to study the chemodynamical evolution of the Galactic disc. This requires a homogeneously analysed sample covering a wide range of ages and distances. In this paper, we present the Open Clusters Chemical Abundances from Spanish Observatories (OCCASO) second data release. This comprises a sample of high-resolution …

2017 Monthly Notices of the Royal Astronomical Society
Gaia 43
The occurrence and wave properties of EMIC waves observed by the Magnetospheric Multiscale (MMS) mission
DOI: 10.1002/2017JA024237 Bibcode: 2017JGRA..122.8228W

Allen, R. C.; Deng, X. H.; Torbert, R. B. +5 more

Electromagnetic ion cyclotron (EMIC) waves can precipitate the ring current ions and relativistic electrons and heat the cold electrons in the magnetosphere. This requires comprehensive knowledge of the occurrence and wave properties of EMIC waves. In the present study, we used the data from one new mission, the Magnetospheric Multiscale (MMS) mis…

2017 Journal of Geophysical Research (Space Physics)
Cluster 43