Search Publications
Masses and Distance of the Young Binary NTTS 045251+3016
Franz, O. G.; Prato, L.; Schaefer, G. H. +4 more
As part of our continuing campaign to measure the masses of pre-main-sequence (PMS) stars dynamically and thus to assess the reliability of the discrepant theoretical calculations of contraction to the main sequence, we present new results for NTTS 045251+3016, a visual and double-lined spectroscopic binary in the Taurus star-forming region (SFR).…
Interstellar Abundances toward X Per, Revisited
Smith, Randall K.; Valencic, Lynne A.
The nearby X-ray binary X Per (HD 24534) provides a useful beacon with which to examine dust grain types and measure elemental abundances in the local interstellar medium (ISM). The absorption features of O, Fe, Mg, and Si along this line of sight were measured using spectra from the Chandra X-Ray Observatory's LETG/ACIS-S and XMM-Newton's RGS ins…
The HIFI spectral survey of AFGL 2591 (CHESS). I. Highly excited linear rotor molecules in the high-mass protostellar envelope
Ceccarelli, C.; Pagani, L.; van der Tak, F. F. S. +2 more
Context. Linear rotor molecules such as CO, HCO+ and HCN are important probes of star-forming gas. For these species, temperatures of ≲ 50 K are sufficient to produce emission lines that are observable from the ground at (sub)millimeter wavelengths. Molecular gas in the environment of massive protostellar objects, however, is known to r…
On the Density Profile of the Globular Cluster M92
Walker, A. R.; Stetson, P. B.; Bono, G. +10 more
We present new number density and surface brightness profiles for the globular cluster M92 (NGC 6341). These profiles are calculated from optical images collected with the CCD mosaic camera MegaCam at the Canada-France-Hawaii Telescope and with the Advanced Camera for Surveys on the Hubble Space Telescope. The ground-based data were supplemented w…
Discovery of a 7 mHz X-Ray Quasi-periodic Oscillation from the most Massive Stellar-mass Black Hole IC 10 X-1
Mushotzky, Richard F.; Pasham, Dheeraj R.; Strohmayer, Tod E.
We report the discovery with XMM-Newton of an ≈7 mHz X-ray (0.3-10.0 keV) quasi-periodic oscillation (QPO) from the eclipsing, high-inclination black hole binary IC 10 X-1. The QPO is significant at >4.33σ confidence level and has a fractional amplitude (% rms) and a quality factor, Q ≡ ν/Δν, of ≈11 and 4, respectively. The overall X-ray (0.3-1…
Experimental investigation into the effects of meteoritic impacts on the spectral properties of phyllosilicates on Mars
Hasegawa, S.; Gavin, P.; Chevrier, V. +2 more
Phyllosilicates have been identified in some of the most highly cratered Noachian terrains on Mars. To study the effects of such impacts on the properties of phyllosilicates, we experimentally shocked six phyllosilicate minerals relevant to the Martian surface: montmorillonite, nontronite, kaolinite, prehnite, chlorite, and serpentine. The shock-t…
The variable X-ray emission of PSR B0943+10
Tiengo, A.; Mereghetti, S.; Esposito, P. +1 more
The old pulsar PSR B0943+10 (P = 1.1 s, characteristic age τ = 5 Myr) is the best example of mode-switching radio pulsar. Its radio emission alternates between a highly organized state with regular drifting subpulses (B mode) and a chaotic emission pattern (Q mode). We present the results of XMM-Newton observations showing that the X-ray propertie…
A massive parsec-scale dust ring nebula around the yellow hypergiant Hen 3-1379
Hutsemékers, D.; Cox, N. L. J.; Vamvatira-Nakou, C.
On the basis of far-infrared images obtained by the Herschel Space Observatory, we report the discovery of a large and massive dust shell around the yellow hypergiant Hen 3-1379. The nebula appears as a detached ring of 1 pc diameter which contains 0.17 M⊙ of dust. We estimate the total gas mass to be 7 M⊙, ejected some 1.6 ×…
A New Cluster of Galaxies Towards the Galactic Bulge, Suzaku J1759-3450
Maeda, Yoshitomo; Haba, Yoshito; Mori, Hideyuki +2 more
We observed an extended X-ray source, designated as Suzaku J1759-3450, with Suzaku and Chandra observations towards 1RXS J175911.0-344921, which is an unidentified X-ray source listed in the ROSAT Bright Source Catalogue. A conspicuous emission line at 6 keV was also found in the Suzaku J1759-3450 spectrum. Assuming the emission line to be K emiss…
Swift/XRT orbital monitoring of the candidate supergiant fast X-ray transient IGR J17354-3255
Esposito, P.; Ducci, L.; Romano, P. +5 more
We report on the Swift/X-ray Telescope (XRT) monitoring of the field of view around the candidate supergiant fast X-ray transient (SFXT) IGR J17354-3255, which is positionally associated with the AGILE/GRID gamma-ray transient AGL J1734-3310. Our observations, which cover 11 days for a total on-source exposure of ~24 ks, span 1.2 orbital periods (…