Search Publications
A Suzaku X-ray study of the mixed-morphology supernova remnant Kes 69 and searching for its gamma-ray counterpart
Sezer, A.; Yamazaki, R.; Ergin, T. +2 more
Kes 69 is a mixed-morphology (MM) supernova remnant (SNR) that is known to be interacting with molecular clouds based on 1720 MHz hydroxyl (OH) maser emission observations in the northeastern and southeastern regions. We present an investigation of Kes 69 using ∼67 ks Suzaku observation. The X-ray spectrum of the whole SNR is well fitted by a non-…
SMHASH: a new mid-infrared RR Lyrae distance determination for the Local Group dwarf spheroidal galaxy Sculptor
Majewski, Steven R.; Madore, Barry F.; Freedman, Wendy L. +12 more
We present a new distance estimation for the Milky Way dwarf spheroidal satellite Sculptor obtained from multi-epoch mid-infrared observations of RR Lyrae stars (RRLs). The 3.6 µm observations have been acquired with the Infrared Array Camera onboard the Spitzer Space Telescope as part of the SMHASH program. Mid-infrared light curves for 42 …
Probing the dynamical state, baryon content, and multiphase nature of galaxy clusters with bright background QSOs
Tripp, Todd M.; Burchett, Joseph N.; Wang, Q. Daniel +5 more
We have initiated a programme to study the physical/dynamical state of gas in galaxy clusters and the impact of the cluster environment on gaseous haloes of individual galaxies using X-ray imaging and UV absorption line spectroscopy of background QSOs. Here, we report results from the analysis Chandra and XMM-Newton archival data of five galaxy cl…
Changes in the pulse phase dependence of X-ray emission lines in 4U 1626-67 with a torque reversal
Paul, Biswajit; Beri, Aru; Dewangan, Gulab C.
We report results from an observation with the XMM-Newton observatory of a unique X-ray pulsar 4U 1626-67. European Photon Imaging Camera-pn data during the current spin-up phase of 4U 1626-67 have been used to study pulse phase dependence of low-energy emission lines. We found strong variability of low-energy emission line at 0.915 keV with the p…
3D mapping of the neutral X-ray absorption in the local interstellar medium: the Gaia and XMM-Newton synergy
Wilms, J.; García, Javier A.; Kallman, Timothy R. +4 more
We present a three-dimensional map of the hydrogen density distribution in the Galactic interstellar medium. The hydrogen-equivalent column densities were obtained from the Exploring the X-ray Transient and variable Sky project (EXTRAS) which provides equivalent NH values from X-ray spectral fits of observations within the XMM-Newton Da…
Intermittency spectra of current helicity in solar active regions
Zhang, Hongqi; Abramenko, V. I.; Kuzanyan, K. M. +2 more
We analyse the spatial distribution of current helicity in solar active regions. A comparison of current helicity maps derived from three different instruments (Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, SDO/HMI, Spectro-Polarimeter on board the Hinode, and Solar Magnetic Field Telescope at the Huairou Solar Observin…
Polarimetric and spectroscopic study of radio-quiet weak emission line quasars
Stalin, C. S.; Petitjean, P.; Srianand, R. +3 more
A small subset of optically selected radio-quiet quasars showing weak or no emission lines may turn out to be the elusive radio-quiet BL Lac objects, or simply be radio-quiet QSOs with a still-forming/shielded broad line region (BLR). High polarization (p > 3-4 per cent), a hallmark of BL Lacs, can be used to test whether some optically selecte…
Thermophysical modelling for high-resolution digital terrain models
Pelivan, I.
A method is presented for efficiently calculating surface temperatures for highly resolved celestial body shapes. A thorough investigation of the necessary conditions leading to reach model convergence shows that the speed of surface temperature convergence depends on factors such as the quality of initial boundary conditions, thermal inertia, ill…
BEANS - a software package for distributed Big Data analysis
Hypki, Arkadiusz
BEANS software is a web-based, easy to install and maintain, new tool to store and analyse in a distributed way a massive amount of data. It provides a clear interface for querying, filtering, aggregating, and plotting data from an arbitrary number of data sets. Its main purpose is to simplify the process of storing, examining, and finding new rel…
On the inner disc structure of MWC480: evidence for asymmetries?
Matter, A.; Lopez, B.; Sitko, M. L. +7 more
Studying the physical conditions structuring the young circumstellar discs is required for understanding the onset of planet formation. Of particular interest is the protoplanetary disc surrounding the Herbig star MWC480. The structure and properties of the circumstellar disc of MWC480 are studied by infrared interferometry and interpreted from a …