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Optical integral field spectroscopy of intermediate redshift infrared bright galaxies
Magdis, G. E.; Farrah, D.; Rigopoulou, D. +10 more
The extreme infrared (IR) luminosity of local luminous and ultraluminous IR galaxies (U/LIRGs; 11 < log L_IR / L_⊙ < 12 and log L_IR / L_⊙ > 12, respectively) is mainly powered by star formation processes triggered by mergers or interactions. While U/LIRGs are rare locally, at z > 1, they become more common, dominate the star formation…
Dynamical masses and mass-to-light ratios of resolved massive star clusters - I. NGC 419 and NGC 1846
Mateo, Mario; Mackey, A. D.; Roederer, Ian U. +4 more
As an introduction of a kinematic survey of Magellanic Cloud (MC) star clusters, we report on the dynamical masses and mass-to-light ratios (M/L) of NGC 419 (Small Magellanic Cloud) and NGC 1846 (Large Magellanic Cloud). We have obtained more than one hundred high-resolution stellar spectra in and around each cluster using the multi-object spectro…
GeV-TeV γ-rays produced by electrons in the kpc-scale jet as a result of Comptonization of the inner jet emission
Bednarek, W.
A few radio galaxies have been discovered to emit GeV-TeV γ-ray emission in spite of the relatively large viewing angles of their jets. We consider a scenario in which such large-angle γ-ray emission is preferentially produced by isotropically distributed relativistic electrons in the kpc-scale jet. These electrons Comptonize soft non-thermal radi…
Classical T-Tauri stars with VPHAS+: II: NGC 6383 in Sh 2-012
Kalari, V. M.
This paper presents optical (ugriHα)-infrared (JHKs, 3.6-8.0 µm) photometry and Gaia astrometry of 55 Classical T-Tauri stars (CTTS) in the star-forming region Sh 2-012 and its central cluster NGC 6383. The sample was identified based on photometric Hα emission linewidths, and has a median age of 2.8 ± 1.6 Myr, with a mass range between 0.3 …
X-ray properties of two transient ULX candidates in galaxy NGC 7090
O'Brien, P. T.; Osborne, J. P.; Page, K. L. +2 more
We report the X-ray data analysis of two transient ultraluminous X-ray sources (ULXs; hereafter X1 and X2) located in the nearby galaxy NGC 7090. While they were not detected in the 2004 XMM-Newton and 2005 Chandra observations, their 0.3-10 keV X-ray luminosities reached >3 × 1039 erg s-1in later XMM-Newton or Swift obser…
Nuclear spallation in active galaxies
Reynolds, C. S.; Gallo, L. C.; García, J. A. +3 more
A number of works point to the presence of narrow emission features at unusual energies in the X-ray spectra of active galactic nuclei or to potentially low iron abundances as possible evidence for the spallation of iron. With the imminence of high-resolution calorimeter spectroscopy, the potential to test spallation models in astrophysical source…
Unveiling the 100 pc scale nuclear radio structure of NGC 6217 with e-MERLIN and the VLA
Muxlow, T. W. B.; Argo, M. K.; Knapen, J. H. +13 more
We present high-sensitivity 1.51 GHz e-MERLIN (e-Multi-Element Radio-Linked Interferometer Network) radio images of the nearby galaxy NGC 6217. We resolve the compact radio source at the centre of NGC 6217 for the first time, finding a twin-lobed structure with a total linear size of ∼4 arcsec (∼400 pc). The radio source does not have a compact ce…
X-ray studies of the gamma-ray pulsar J1826-1256 and its pulsar wind nebula with Chandra and XMM-Newton
Karpova, Anna V.; Zyuzin, Dmitry A.; Shibanov, Yuriy A.
We have analysed archival XMM-Newton and Chandra observations of the γ-ray radio-quiet pulsar J1826-1256 and its pulsar wind nebula. The pulsar spectrum can be described by a power-law model with photon index Γ ≈ 1. We find that the nebular spectrum softens with increasing distance from the pulsar, implying synchrotron cooling. The empirical inter…
New hot subdwarf variables from the EC survey
Kilkenny, D.; Lynas-Gray, A. E.; Worters, H. L.
We present new results for hot subdwarf stars from the Edinburgh-Cape (EC) blue object survey. EC 03089-6421, an sdO star recently discovered to be a very rapid pulsator with periods near 31.1 and 34.2 s (29.2 and 32.1 mHz), is shown to have an even faster pulsation near 26.6 s (37.6 mHz) although all pulsations are variable in amplitude and effec…
The radial distribution of blue stragglers in Galactic globular cluster NGC 6656 - clues to the dynamical status
Yadav, R. K. S.; Singh, Gaurav
We present the dynamical status of the Galactic globular cluster NGC 6656 using the spatial distribution of blue straggler stars (BSSs). A combination of multi-wavelength high-resolution space- and ground-based data are used to cover a large cluster region. We determine the centre of gravity (Cgrav) and construct the projected density p…