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Ejecta detection in the middle-aged Galactic supernova remnant G296.1-0.5 observed with Suzaku
Sezer, A.; Gök, F.
In this paper, we report the detection of ejecta in the middle-aged Galactic supernova remnant G296.1-0.5 with the X-ray Imaging Spectrometer onboard the Suzaku satellite. The spectra of three lobes, north, south-east and south-west and interlobe regions, consist of soft (0.3-2.0 keV) emission originated from non-equilibrium ionization plasma. In …
The XMM Cluster Survey: predicted overlap with the Planck Cluster Catalogue
Hilton, Matt; Stott, John P.; Stanford, S. Adam +14 more
We present a list of 15 clusters of galaxies, serendipitously detected by the XMM Cluster Survey (XCS), that have a high probability of detection by the Planck satellite. Three of them already appear in the Planck Early Sunyaev-Zel'dovich (ESZ) catalogue. The estimation of the Planck detection probability assumes the flat Lambda cold dark matter (…
Low-frequency radio spectrum of LS 5039 during periastron and apastron passages
Bhattacharyya, Subir; Bhatt, Nilay; Choudhury, Manojendu +2 more
We have recently studied LS 5039, a gamma-ray binary, with the Giant Metrewave Radio Telescope during its periastron and apastron passage. The results presented here show that the spectra are inverted at low frequency and the flux densities do not differ significantly for two different orbital phases. Assuming that the free-free absorption of radi…
Intermediate old star clusters in a young starburst: the case of NGC 5253
Gallagher, J.; Crnojević, D.; Harbeck, D.
We investigate the star cluster population in the outer parts of the starburst galaxy NGC 5253 using archive images taken with the Hubble Space Telescope's Advanced Camera for Surveys. Based on the F415W, F555W and F814W photometry ages and masses are estimated for bona fide star cluster candidates. We find three potentially massive (≥105
Period-luminosity relations for Small Magellanic Cloud Cepheid based on AKARI archival data
Ngeow, Chow-Choong; Kanbur, Shashi M.; Citro, Danielle M.
In this work we matched the AKARI archival data to the Optical Gravitational Lensing Experiment III (OGLE-III) catalogue to derive the mid-infrared period-luminosity (PL) relations for Small Magellanic Cloud (SMC) Cepheids. Mismatched AKARI sources were eliminated using random-phase colours obtained from the full I-band light curves from OGLE-III.…
High-resolution optical imaging of the core of the globular cluster M15 with FastCam
Rodríguez, Luis F.; Rebolo, Rafael; Díaz-Sánchez, Anastasio +6 more
We present high-resolution I -band imaging of the core of the globular cluster M15 obtained at the 2.5-m Nordic Optical Telescope with FastCam, a low readout noise L3CCD-based instrument. Short exposure times (30 ms) were used to record 200 000 images (512 × 512 pixels each) over a period of 2 h and 43 min. The lucky imaging technique was then app…
Modelling the flaring activity of the high-z, hard X-ray-selected blazar IGR J22517+2217
Ghisellini, G.; de Rosa, A.; Ajello, M. +6 more
We present new Suzaku and Fermi data and re-analysed archival hard X-ray data from the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) and Swift-Burst Alert Telescope (BAT) surveys to investigate the physical properties of the luminous, high-redshift, hard X-ray-selected blazar IGR J22517+2217, through the modelling of its broad-band sp…
Is there a compact companion orbiting the late O-type binary star HD 164816?
Neuhäuser, R.; Stahl, O.; Chini, R. +7 more
We present a multi-wavelength (X-ray, γ-ray, optical and radio) study of HD 164816, a late O-type X-ray detected spectroscopic binary. X-ray spectra are analysed and the X-ray photon arrival times are checked for pulsation. In addition, newly obtained optical spectroscopic monitoring data on HD 164816 are presented. They are complemented by availa…
Discovery of shocked H2 around OH 231.8+4.2
Forde, K. P.; Gledhill, T. M.
We present K-band integral field observations of the circumstellar envelope of the evolved star OH 231.8+4.2. Spatial and spectral information was simultaneously acquired using the SINFONI integral field unit, with adaptive optics, on the Very Large Telescope. The observations reveal the discovery of H2 emission (1) around the centre of…
The structure of the planetary nebula NGC 2371 in the visible and mid-infrared
Ramos-Larios, Gerardo; Phillips, J. P.
We investigate the structure of the planetary nebula NGC 2371 using [O III] λ5007 imaging taken with the Jacobus Kapteyn 1.0 m telescope, and [N II] λ6584, [O III] λ5007 and Hα results acquired with the Hubble Space Telescope. These are supplemented with archival mid-infrared (MIR) observations taken with the Spitzer Space Telescope. We note the p…