Search Publications
Discovery of hard phase lags in the pulsed emission of GRO J1744-28
Sanna, A.; Di Salvo, T.; Burderi, L. +4 more
We report on the discovery and energy dependence of hard phase lags in the 2.14 Hz pulsed profiles of GRO J1744-28. We used data from XMM-Newton and NuSTAR. We were able to well constrain the lag spectrum with respect to the softest (0.3-2.3 keV) band: the delay shows increasing lag values reaching a maximum delay of ∼12 ms, between 6 and 6.4 keV.…
Buoyancy-driven inflow to a relic cold core: the gas belt in radio galaxy 3C 386
Birkinshaw, M.; Worrall, D. M.; Kraft, R. P. +1 more
We report measurements from an XMM-Newton observation of the low-excitation radio galaxy 3C 386. The study focusses on an X-ray-emitting gas belt, which lies between and orthogonal to the radio lobes of 3C 386 and has a mean temperature of 0.94 ± 0.05 keV, cooler than the extended group atmosphere. The gas in the belt shows temperature structure w…
The complex high-mass star-forming region IRAS 15507-5359
Roth, M.; Elia, D.; Persi, P. +2 more
The far-infrared IRAS 15507-5359 source is known to be a medium-mass star-forming region associated with a compact H II region and a near-infrared embedded cluster. We present a survey of infrared-calibrated images ranging from 1.2 to 500 µm obtained with the Baade telescope at Las Campanas Observatory, and the Herschel space telescope with …
AGB stars in Leo P and their use as metallicity probes
Lee, Chien-Hsiu
Leo P is the most metal-poor yet star-forming galaxy in the local volume, and has the potential to serve as a local counterpart to interpret the properties of distant galaxies in the early universe. We present a comprehensive search of asymptotic giant branch (AGB) stars in Leo P using deep infrared imaging. AGB stars are the major dust contributo…
The nature of the cataclysmic variable PT Per
Watson, M. G.; Osborne, J. P.; Schwope, A. D. +2 more
We present a study of the cataclysmic variable star PT Per based on archival XMM-Newton X-ray data and new optical spectroscopy from the William Herschel Telescope (WHT) with Intermediate dispersion Spectrograph and Imaging System (ISIS). The X-ray data show deep minima which recur at a period of 82 min and a hard, unabsorbed X-ray spectrum. The o…
The bandmerged Planck Early Release Compact Source Catalogue: probing sub-structure in the molecular gas at high Galactic latitude
Helou, G.; McGehee, P.; Pearson, T. J. +3 more
The Planck Early Release Compact Source Catalogue (ERCSC) includes nine lists of highly reliable sources, individually extracted at each of the nine Planck frequency channels. To facilitate the study of the Planck sources, especially their spectral behaviour across the radio/infrared frequencies, we provide a `bandmerged' catalogue of the ERCSC so…
Fine structures at pore boundary
Bharti, L.; Quintero Noda, C.; Joshi, C. +2 more
We present high resolution observations of fine structures at pore boundaries. The inner part of granules towards umbra show dark striations which evolve into a filamentary structure with dark core and `Y' shape at the head of the filaments. These filaments migrate into the umbra similar to penumbral filaments. These filaments show higher temperat…
Observations of the planetary nebula RWT 152 with OSIRIS/GTC
Solano, E.; Ulla, A.; Miranda, L. F. +2 more
RWT 152 is one of the few known planetary nebulae with an sdO central star. We present subarcsecond red tunable filter Hα imaging and intermediate-resolution, long-slit spectroscopy of RWT 152 obtained with OSIRIS/GTC (Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy/Gran Telescopio Canarias) with the goal of anal…
Fundamental stellar parameters for selected T-Tauri stars in the Chamaeleon and Rho Ophiuchus star-forming regions
James, D. J.; Bouvier, J.; Santos, N. C. +4 more
We present the results of an optical photometry and high-resolution spectroscopy campaign for a modest sample of X-ray selected stars in the Chamaeleon and Rho Ophiuchus star-forming regions. With R∼ 50 000 optical spectra, we establish kinematic membership of the parent association and confirm stellar youth for each star in our sample. With the a…
Searching for X-ray sources in nearby late-type galaxies with low-star formation rates
Kaaret, P.; Poutanen, J.; Kajava, J. J. E. +4 more
Late-type non-starburst galaxies have been shown to contain X-ray emitting objects, some being ultraluminous X-ray sources. We report on XMM-Newton observations of 11 nearby, late-type galaxies previously observed with the Hubble Space Telescope (HST) in order to find such objects. We found 18 X-ray sources in or near the optical extent of the gal…