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Orbital Decay in a 20 Minute Orbital Period Detached Binary with a Hydrogen-poor Low-mass White Dwarf
DOI: 10.3847/2041-8213/ab53e5 Bibcode: 2019ApJ...886L..12B

Kulkarni, S. R.; Duev, Dmitry A.; Riddle, Reed +14 more

We report the discovery of a detached double white dwarf binary with an orbital period of ≈20.6 minutes, PTF J053332.05+020911.6. The visible object in this binary, PTF J0533+0209B, is a ≈0.17 M mass white dwarf with a helium-dominated atmosphere containing traces of hydrogen. This object exhibits ellipsoidal variations due to tidal d…

2019 The Astrophysical Journal
Gaia 47
A gap in HD 92945's broad planetesimal disc revealed by ALMA
DOI: 10.1093/mnras/stz049 Bibcode: 2019MNRAS.484.1257M

Wyatt, M. C.; Marino, S.; Kennedy, G. M. +4 more

In the last few years, multiwavelength observations have revealed the ubiquity of gaps/rings in circumstellar discs. Here we report the first ALMA observations of HD 92945 at 0.86 mm, which reveal a gap at about 73 ± 3 au within a broad disc of planetesimals that extends from 50 to 140 au. We find that the gap is 20^{+10}_{-8} au wide. If cleared …

2019 Monthly Notices of the Royal Astronomical Society
Gaia 47
Resolving CO (2-1) in z ∼ 1.6 Gas-rich Cluster Galaxies with ALMA: Rotating Molecular Gas Disks with Possible Signatures of Gas Stripping
DOI: 10.3847/1538-4357/aaf1c6 Bibcode: 2019ApJ...870...56N

Cooper, M. C.; van Kampen, E.; Demarco, R. +10 more

We present the first spatially resolved observations of molecular gas in a sample of cluster galaxies beyond z > 0.1. Using ALMA, we detect CO (2-1) in eight z ∼ 1.6 cluster galaxies, all within a single 70″ primary beam. The cluster, SpARCS-J0225, was discovered by the Spitzer Adaptation of the Red-sequence Cluster Survey, and is replete with …

2019 The Astrophysical Journal
eHST 47
Discovery of Three New Transiting Hot Jupiters: WASP-161 b, WASP-163 b, and WASP-170 b
DOI: 10.3847/1538-3881/aaf422 Bibcode: 2019AJ....157...43B

Bouchy, F.; Queloz, D.; Delrez, L. +28 more

We present the discovery of three new transiting hot Jupiters by the WASP-South project, WASP-161 b, WASP-163 b, and WASP-170 b. Follow-up radial velocities obtained with the Euler/CORALIE spectrograph and transit light curves obtained with the TRAPPIST-North, TRAPPIST-South, SPECULOOS-South, NITES, and Euler telescopes have enabled us to determin…

2019 The Astronomical Journal
Gaia 47
Hubble Space Telescope Nondetection of PSR J2144-3933: The Coldest Known Neutron Star
DOI: 10.3847/1538-4357/ab0f38 Bibcode: 2019ApJ...874..175G

Pavlov, George G.; Kargaltsev, Oleg; Guillot, Sebastien +4 more

We report nondetections of the ∼3 × 108 yr old, slow, isolated, rotation-powered pulsar PSR J2144-3933 in observations with the Hubble Space Telescope in one optical band (F475X) and two far-ultraviolet bands (F125LP and F140LP), yielding upper bounds {F}{{F}475{{X}}}< 22.7 {nJy}, {F}{{F}125{LP}}< 5.9 {nJy}, …

2019 The Astrophysical Journal
Gaia eHST 47
Rejuvenated galaxies with very old bulges at the origin of the bending of the main sequence and of the `green valley'
DOI: 10.1093/mnras/stz2130 Bibcode: 2019MNRAS.489.1265M

Daddi, Emanuele; Juneau, Stéphanie; Liu, Daizhong +11 more

We investigate the nature of star-forming galaxies with reduced specific star formation rate (sSFR) and high stellar masses, those `green valley' objects that seemingly cause a reported bending, or flattening, of the star-forming main sequence. The fact that such objects host large bulges recently led some to suggest that the internal formation of…

2019 Monthly Notices of the Royal Astronomical Society
Herschel eHST 47
Constraints on the chemical enrichment history of the Perseus Cluster of galaxies from high-resolution X-ray spectroscopy
DOI: 10.1093/mnras/sty3220 Bibcode: 2019MNRAS.483.1701S

Yamaguchi, H.; Simionescu, A.; Kaastra, J. S. +32 more

High-resolution spectroscopy of the core of the Perseus Cluster of galaxies, using the Hitomi satellite above 2 keV and the XMM-Newton Reflection Grating Spectrometer at lower energies, provides reliable constraints on the abundances of O, Ne, Mg, Si, S, Ar, Ca, Cr, Mn, Fe, and Ni. Accounting for all known systematic uncertainties, the Ar/Fe, Ca/F…

2019 Monthly Notices of the Royal Astronomical Society
Hitomi XMM-Newton 47
The outer halo globular cluster system of M31 - III. Relationship to the stellar halo
DOI: 10.1093/mnras/stz072 Bibcode: 2019MNRAS.484.1756M

Côté, P.; Mackey, A. D.; Martin, N. F. +10 more

We utilize the final catalogue from the Pan-Andromeda Archaeological Survey to investigate the links between the globular cluster system and field halo in M31 at projected radii Rproj = 25-150 kpc. In this region the cluster radial density profile exhibits a power-law decline with index Γ = -2.37 ± 0.17, matching that for the stellar ha…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 47
Butterfly in a Cocoon, Understanding the Origin and Morphology of Globular Cluster Streams: The Case of GD-1
DOI: 10.3847/1538-4357/ab2e07 Bibcode: 2019ApJ...881..106M

Malhan, Khyati; Ibata, Rodrigo A.; Carlberg, Raymond G. +2 more

Tidally disrupted globular cluster (GC) streams are usually observed, and therefore perceived, as narrow, linear, and one-dimensional structures in the 6D phase space. Here, we show that the GD-1 stellar stream, which is the tidal debris of a disrupted GC, possesses a secondary diffuse and extended stellar component (∼100 pc wide) around it, detec…

2019 The Astrophysical Journal
Gaia 47
Multiphase quasar-driven outflows in PG 1114+445. I. Entrained ultra-fast outflows
DOI: 10.1051/0004-6361/201935275 Bibcode: 2019A&A...627A.121S

Piconcelli, Enrico; Tombesi, Francesco; Serafinelli, Roberto +3 more

Substantial evidence in the last few decades suggests that outflows from supermassive black holes (SMBH) may play a significant role in the evolution of galaxies. These outflows, powered by active galactic nuclei (AGN), are thought to be the fundamental mechanism by which the SMBH transfers a significant fraction of its accretion energy to the sur…

2019 Astronomy and Astrophysics
XMM-Newton 47