Search Publications
NuSTAR and XMM-Newton broad-band spectrum of SAX J1808.4-3658 during its latest outburst in 2015
Sanna, A.; Papitto, A.; Di Salvo, T. +4 more
The first discovered accreting millisecond pulsar, SAX J1808.4-3658, went into X-ray outburst in 2015 April. We triggered a 100 ks XMM-Newton ToO, taken at the peak of the outburst, and a 55 ks NuSTAR ToO, performed 4 d apart. We report here the results of a detailed spectral analysis of both the XMM-Newton and NuSTAR spectra. While the XMM-Newton…
Close-up view of an ongoing merger between the NGC 4839 group and the Coma cluster - a post-merger scenario
Churazov, E.; Forman, W.; Jones, C. +5 more
We study a merger of the NGC 4839 group with the Coma cluster using X-ray observations from the XMM-Newton and Chandra telescopes. X-ray data show two prominent features: (i) a long (∼600 kpc in projection) and bent tail of cool gas trailing (towards south-west) the optical centre of NGC 4839, and (ii) a `sheath' region of enhanced X-ray surface b…
On the Oosterhoff dichotomy in the Galactic bulge: I. Spatial distribution
Smolec, R.; Grebel, E. K.; Catelan, M. +3 more
We present a study of the Oosterhoff (Oo) dichotomy in the Galactic bulge using 8141 fundamental-mode RR Lyrae stars. We used public photometric data from the Optical Gravitational Lensing Experiment and the Vista Variables in the Vía Láctea survey. We carefully selected fundamental-mode stars without modulation and without association with any gl…
Two sub-millimetre bright protoclusters bounding the epoch of peak star-formation activity
Ivison, R. J.; Smail, Ian; Gurwell, M. +8 more
We present James Clerk Maxwell Telescope Submillimetre Common-User Bolometer Array 2 (SCUBA-2) 850 and 450 µm observations (σ850 ∼ 0.5 mJy, σ450 ∼ 5 mJy) of the HS1549+19 and HS1700+64 survey fields containing two of the largest known galaxy overdensities at z = 2.85 and 2.30, respectively. We detect 56 sub-millimetre g…
Constraining Lyman-alpha spatial offsets at 3 < z < 5.5 from VANDELS slit spectroscopy
Schaerer, D.; Cullen, F.; Thomas, R. +20 more
We constrain the distribution of spatially offset Lyman-alpha emission (Ly α) relative to rest-frame ultraviolet emission in ∼300 high redshift (3 < z < 5.5) Lyman-break galaxies (LBGs) exhibiting Ly α emission from VANDELS, a VLT/VIMOS slit-spectroscopic survey of the CANDELS Ultra Deep Survey and Chandra Deep Field South fields (≃0.2 deg
Resolving on 100 pc scales the UV-continuum in Lyman-α emitters between redshift 2 and 3 with gravitational lensing
Vegetti, S.; McKean, J. P.; Auger, M. W. +1 more
We present a study of 17 LAEs at redshift 2 < z < 3 gravitationally lensed by massive early-type galaxies (ETGs) at a mean redshift of approximately 0.5. Using a fully Bayesian grid-based technique, we model the gravitational lens mass distributions with elliptical power-law profiles and reconstruct the ultraviolet (UV)-continuum surface-bri…
The spectral energy distributions of active galactic nuclei
Salvato, M.; Ricci, C.; Brown, M. J. I. +5 more
We present spectral energy distributions (SEDs) of 41 active galactic nuclei, derived from multiwavelength photometry and archival spectroscopy. All of the SEDs span at least 0.09 to 30 µm, but in some instances wavelength coverage extends into the X-ray, far-infrared, and radio. For some active galactic nuclei (AGNs) we have fitted the meas…
The Milky Way Project second data release: bubbles and bow shocks
Kobulnicky, Henry A.; Kendrew, Sarah; Xu, Duo +9 more
Citizen science has helped astronomers comb through large data sets to identify patterns and objects that are not easily found through automated processes. The Milky Way Project (MWP), a citizen science initiative on the Zooniverse platform, presents internet users with infrared (IR) images from Spitzer Space Telescope Galactic plane surveys. MWP …
Primeval very low-mass stars and brown dwarfs - VI. Population properties of metal-poor degenerate brown dwarfs
Zapatero Osorio, M. R.; Pinfield, D. J.; Burgasser, A. J. +4 more
We presented 15 new T dwarfs that were selected from UKIRT Infrared Deep Sky Survey, Visible and Infrared Survey Telescope for Astronomy , and Wide-field Infrared Survey Explorer surveys, and confirmed with optical to near-infrared spectra obtained with the Very Large Telescope and the Gran Telescopio Canarias. One of these new T dwarfs is mildly …
The Second LBA Calibrator Survey of southern compact extragalactic radio sources - LCS2
Horiuchi, Shinji; Petrov, Leonid; de Witt, Alet +2 more
We present the second catalogue of accurate positions and correlated flux densities for 1100 compact extragalactic radio sources that were not observed before 2008 at high angular resolution. The catalogue spans the declination range [ -90°, -30°] and was constructed from 19 24-h VLBI observing sessions with the Australian Long Baseline Array at 8…