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Hour time-scale QPOs in the X-ray and radio emission of LS I +61°303
Cimò, G.; Chernyakova, M.; Massi, M. +2 more
LS I +61°303 is an X-ray binary with a radio outburst every ∼27 d. Previous studies of the stellar system revealed radio microflares superimposed on the large radio outburst. We present here new radio observations of LS I +61°303 at 2.2 GHz with the Westerbork Synthesis Radio Telescope (WSRT). Using various timing analysis methods, we find signifi…
The character of the warm ionized medium
Geyer, Marisa; Walker, Mark A.
Herschel observations of far-infrared N+ emission lines have demonstrated that dense plasma, with n_ e∼ 30 cm^{-3}, is ubiquitous in the inner Galactic plane. By combining the information from Herschel with other tracers of ionized gas, we build a picture of this dense plasma. We adopt a collisional ionization model, so the analysis is …
A magnetic study of the δ Scuti variable HD 21190 and the close solar-type background star CPD -83°64B
Ilyin, I.; Niemczura, E.; Hubrig, S. +3 more
HD 21190 is a known δ Scuti star showing Ap star characteristics and a variability period of 3.6 h discovered by the Hipparcos mission. Using Gaia DR1 data for an astrometric analysis, it was recently suggested that HD 21190 forms a physical binary system with the companion CPD -83° 64B. An atmospheric chemical analysis based on High Accuracy Radi…
The role of external far-ultraviolet irradiation in the survival of astrophysical ices in Elias 29
Rocha, W. R. M.; Pilling, S.
The survival of astrophysical ices in star-forming regions depends on the suitability of temperature, density and radiation conditions. In this article, the role of the interstellar radiation field (ISRF) on ices in Elias 29 is addressed. This object is the most luminous protostar in the ρ Oph E molecular cloud and is surrounded by many young stel…
Multiconfiguration Dirac-Hartree-Fock calculations of energy levels and radiative rates of Fe VII
Li, Yang; Xu, Xiaokai; Li, Bowen +2 more
Detailed calculations are performed for 134 fine-structure levels of the 3p63d2, 3p63d4s, 3p53d3 and 3p63d4p configurations in Fe VII using the multiconfiguration Dirac-Hartree-Fock (MCDHF) and relativistic configuration interaction (RCI) methods. Important electron correlation effe…
A photometric study of globular clusters observed by the APOGEE survey
Masseron, Thomas; Monelli, Matteo; García-Hernández, D. A. +8 more
In this paper, we describe the photometric and spectroscopic properties of multiple populations in seven northern globular clusters. In this study, we employ precise ground-based photometry from the private collection of Stetson, space photometry from the Hubble Space Telescope (HST), literature abundances of Na and O, and Apache Point Observatory…
Decoupled black hole accretion and quenching: the relationship between BHAR, SFR and quenching in Milky Way- and Andromeda-mass progenitors since z = 2.5
Morrison, G.; Papovich, C.; Glazebrook, K. +13 more
We investigate the relationship between the black hole accretion rate (BHAR) and star formation rate (SFR) for Milky Way (MW) and Andromeda (M31)-mass progenitors from z = 0.2 to 2.5. We source galaxies from the Ks-band-selected ZFOURGE survey, which includes multiwavelength data spanning 0.3-160 µm. We use decomposition software …
A Hubble Space Telescope imaging study of four FeLoBAL quasar host galaxies
Vestergaard, M.; Fan, X.; Lawther, D.
We study the host galaxies of four Iron Low-Ionization Broad Absorption-line Quasars (FeLoBALs), using Hubble Space Telescope imaging data, investigating the possibility that they represent a transition between an obscured active galactic nucleus (AGN) and an ordinary optical quasar. In this scenario, the FeLoBALs represent the early stage of merg…
Faint γ-ray sources at low redshift: the radio galaxy IC 1531
Vignali, C.; Grandi, P.; Siemiginowska, A. +6 more
We present a multiwavelength study of IC 1531 (z = 0.02564), an extragalactic radio source associated with the γ-ray object 3FGL J0009.9 - 3206 and classified as a blazar of uncertain type in the Third Fermi-Large Area Telescope AGN catalog (3LAC). A core-jet structure, visible in radio and X-rays, is enclosed within a ∼220 kpc wide radio structur…
Enhanced dust emissivity power-law index along the western H α filament of NGC 1569
Onaka, T.; Kaneda, H.; Ishihara, D. +4 more
We used a data set from AKARI and Herschel images at wavelengths from 7 to 500 µm to catch the evidence of dust processing in galactic winds in NGC 1569. Images show a diffuse infrared (IR) emission extending from the galactic disc into the halo region. The most prominent filamentary structure seen in the diffuse IR emission is spatially in …