Search Publications
SCORPIO: a deep survey of radio emission from the stellar life-cycle
Umana, G.; Agliozzo, C.; Trigilio, C. +7 more
Radio emission has been detected in a broad variety of stellar objects from all stages of stellar evolution. However, most of our knowledge originates from targeted observations of small samples, which are strongly biased to sources which are peculiar at other wavelengths. In order to tackle this problem we have conducted a deep 1.4 GHz survey by …
Spectral and timing analysis of the mHz QPOs in the neutron-star low-mass X-ray binary 4U 1636-53
Méndez, Mariano; Keek, L.; Zhang, Guobao +1 more
We investigate the spectral and timing properties of the millihertz quasi-periodic oscillations (mHz QPOs) in neutron-star low-mass X-ray binary 4U 1636-53 using XMM-Newton and Rossi X-ray Timing Explorer (RXTE) observations. The mHz QPOs in the XMM-Newton/RXTE observations show significant frequency variation and disappear right before type I X-r…
Deep rest-frame far-UV spectroscopy of the giant Lyman α emitter `Himiko'
Nørgaard-Nielsen, H. U.; Fynbo, J. P. U.; Ouchi, M. +3 more
We present deep 10 h VLT/XSHOOTER spectroscopy for an extraordinarily luminous and extended Ly α emitter at z = 6.595 referred to as Himiko and first discussed by Ouchi et al., with the purpose of constraining the mechanisms powering its strong emission. Complementary to the spectrum, we discuss near-infrared imaging data from the CANDELS survey. …
New members of the TW Hydrae Association and two accreting M-dwarfs in Scorpius-Centaurus
Murphy, Simon J.; Bento, Joao; Lawson, Warrick A.
We report the serendipitous discovery of several young mid-M stars found during a search for new members of the 30-40 Myr-old Octans Association. Only one of the stars may be considered a possible Octans(-Near) member. However, two stars have proper motions, kinematic distances, radial velocities, photometry and Li I λ6708 measurements consistent …
A CO-rich merger shaping a powerful and hyperluminous infrared radio galaxy at z = 2: the Dragonfly Galaxy
Pentericci, L.; Colina, L.; Villar-Martín, M. +17 more
In the low-redshift Universe, the most powerful radio sources are often associated with gas-rich galaxy mergers or interactions. We here present evidence for an advanced, gas-rich (`wet') merger associated with a powerful radio galaxy at a redshift of z ∼ 2. This radio galaxy, MRC 0152-209, is the most infrared-luminous high-redshift radio galaxy …
The 11.2 µm emission of PAHs in astrophysical objects
Sarre, P. J.; Candian, A.
The 11.2-µm emission band belongs to the family of the `unidentified' infrared emission bands seen in many astronomical environments. In this work, we present a theoretical interpretation of the band characteristics and profile variation for a number of astrophysical sources in which the carriers are subject to a range of physical conditions…
Ongoing growth of the brightest cluster galaxies via major dry mergers in the last ∼6 Gyr
Liu, F. S.; Meng, X. M.; Lei, F. J. +1 more
Brightest cluster galaxies (BCGs) might have been assembled relatively late (z < 1) via mergers. By exploiting the high-resolution HST/ACS imaging, we find four BCGs (COSMOS-P 125516, 102810, 036694 and 089357) in major dry merging in 29 X-ray clusters at 0.3 ≤ z ≤ 0.6 in the Cosmological Evolutionary Survey (COSMOS). These BCGs show prominent …
Confirming HD 23478 as a new magnetic B star hosting an Hα-bright centrifugal magnetosphere
Wade, G. A.; Bohlender, D. A.; Neiner, C. +11 more
In this paper, we report 23 magnetic field measurements of the B3IV star HD 23478: 12 obtained from high-resolution Stokes V spectra using the ESPaDOnS (Canada-France-Hawaii Telescope) and Narval (Télescope Bernard Lyot) spectropolarimeters, and 11 from medium-resolution Stokes V spectra obtained with the DimaPol spectropolarimeter (Dominion Astro…
Large-scale environment of z ∼ 5.7 C IV absorption systems -II. Spectroscopy of Lyman α emitters
Ouchi, Masami; Koyama, Yusei; Díaz, C. Gonzalo +2 more
The flow of baryons to and from a galaxy, which is fundamental for galaxy formation and evolution, can be studied with galaxy-metal absorption system pairs. Our search for galaxies around C IV absorption systems at z ∼ 5.7 showed an excess of photometric Lyman α emitter (LAE) candidates in the fields J1030+0524 and J1137+3549. Here, we present spe…
Variations in the cyclotron resonant scattering features during 2011 outburst of 4U 0115+63
Dewangan, G. C.; Bhattacharya, D.; Mukherjee, D. +2 more
We study the variations in the Cyclotron Resonant Scattering Feature (CRSF) during 2011 outburst of the high mass X-ray binary 4U 0115+63 using observations performed with Suzaku, RXTE, Swift and INTEGRAL satellites. The wide-band spectral data with low-energy coverage allowed us to characterize the broad-band continuum and detect the CRSFs. We fi…