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IN-SYNC. VIII. Primordial Disk Frequencies in NGC 1333, IC 348, and the Orion A Molecular Cloud
Da Rio, Nicola; Meyer, Michael R.; Yao, Yuhan +2 more
In this paper, we address two issues related to primordial disk evolution in three clusters (NGC 1333, IC 348, and Orion A) observed by the INfrared Spectra of Young Nebulous Clusters (IN-SYNC) project. First, in each cluster, averaged over the spread of age, we investigate how disk lifetime is dependent on stellar mass. The general relation in IC…
Discovery of Extended Infrared Emission around the Neutron Star RXJ0806.4-4123
Luhman, K. L.; Pavlov, G. G.; Williams, C. C. +3 more
Following up on a faint detection of a near-infrared (NIR) source at the position of the X-ray thermal isolated neutron star RX J0806.4-4123, we present new Hubble Space Telescope observations in the H-band. The NIR source is unambiguously detected with a Vega magnitude of 23.7 ± 0.2 (flux density of 0.40 ± 0.06 µJy at λ = 1.54 µm). Th…
Initial products of Akatsuki 1-µm camera
Imamura, Takeshi; Ando, Hiroki; Ueno, Munetaka +25 more
The status and initial products of the 1-µm camera onboard the Akatsuki mission to Venus are presented. After the successful retrial of Venus' orbit insertion on Dec. 2015 (5 years after the failure in Dec. 2010), and after a long cruise under intense radiation, damage in the detector seems small and fortunately insignificant in the final qu…
Evidence of Twisting and Mixed-polarity Solar Photospheric Magnetic Field in Large Penumbral Jets: IRIS and Hinode Observations
Tiwari, Sanjiv K.; Winebarger, Amy R.; De Pontieu, Bart +4 more
A recent study using Hinode (Solar Optical Telescope/Filtergraph [SOT/FG]) data of a sunspot revealed some unusually large penumbral jets that often repeatedly occurred at the same locations in the penumbra, namely, at the tail of a penumbral filament or where the tails of multiple penumbral filaments converged. These locations had obvious photosp…
NGC 4051: Black hole mass and photon index-mass accretion rate correlation
Titarchuk, Lev; Seifina, Elena; Chekhtman, Alexandre
We present a discovery of the correlation between the X-ray spectral (photon) index and mass accretion rate observed in an active galactic nucleus, NGC 4051. We analyzed spectral transition episodes observed in NGC 4051 using XMM-Newton, Suzaku and RXTE. We applied a scaling technique for a black hole (BH) mass evaluation which uses a correlation …
Black Holes and Neutron Stars in Nearby Galaxies: Insights from NuSTAR
Wik, D. R.; Lehmer, B. D.; Hornschemeier, A. E. +8 more
Nearby galaxy surveys have long classified X-ray binaries (XRBs) by the mass category of their donor stars (high-mass and low-mass). The NuSTAR observatory, which provides imaging data at E > 10 keV, has enabled the classification of extragalactic XRBs by their compact object type: neutron star (NS) or black hole (BH). We analyzed NuSTAR/Chandr…
Short-term variability and mass loss in Be stars. IV. Two groups of closely spaced, approximately equidistant frequencies in three decades of space photometry of ν Puppis (B7-8 IIIe)
Wang, L.; Handler, G.; Carciofi, A. C. +13 more
Context. In early-type Be stars, groups of nonradial pulsation (NRP) modes with numerically related frequencies may be instrumental for the release of excess angular momentum through mass-ejection events. Difference and sum/harmonic frequencies often form additional groups.
Aims: The purpose of this study is to find out whether a similar freq…
2004 EW95: A Phyllosilicate-bearing Carbonaceous Asteroid in the Kuiper Belt
Fraser, Wesley C.; Brown, Michael E.; Puzia, Thomas H. +2 more
Models of the Solar System’s dynamical evolution predict the dispersal of primitive planetesimals from their formative regions among the gas-giant planets due to the early phases of planetary migration. Consequently, carbonaceous objects were scattered both into the outer asteroid belt and out to the Kuiper Belt. These models predict that the Kuip…
Measuring the Wilson depression of sunspots using the divergence-free condition of the magnetic field vector
Solanki, S. K.; Lagg, A.; Löptien, B. +1 more
Context. The Wilson depression is the difference in geometric height of unit continuum optical depth between the sunspot umbra and the quiet Sun. Measuring the Wilson depression is important for understanding the geometry of sunspots. Current methods suffer from systematic effects or need to make assumptions on the geometry of the magnetic field. …
AGN feedback in the Phoenix cluster
Liu, H.; Fabian, A. C.; Reynolds, C. S. +5 more
Active galactic nuclei (AGNs) release a huge amount of energy into the intracluster medium, with the consequence of offsetting cooling and star formation (AGN feedback) in the centres of cool-core clusters. The Phoenix cluster is among the most massive clusters of galaxies known in the Universe. It hosts a powerful starburst of several hundreds of…