Search Publications
Tightening the belt: Constraining the mass and evolution in SDC335
Avison, A.; Peretto, N.; Fuller, G. A. +3 more
Aims: Recent ALMA observations identified one of the most massive star-forming cores yet observed in the Milky Way: SDC335-MM1, within the infrared dark cloud SDC335.579-0.292. Along with an accompanying core MM2, SDC335 appears to be in the early stages of its star formation process. We aim to constrain the properties of the stars forming wi…
Recent highlights from Cluster, the first 3-D magnetospheric mission
Escoubet, C. P.; Goldstein, M. L.; Masson, A. +1 more
The Cluster mission has been operated successfully for 14 years. During this time period, the evolution of the orbit has enabled Cluster to sample many more magnetospheric regions than was initially anticipated. So far, the separation of the Cluster spacecraft has been changed more than 30 times and has ranged from a few kilometres up to 36 000 km…
Constraining dark sector perturbations I: cosmic shear and CMB lensing
Battye, Richard A.; Moss, Adam; Pearson, Jonathan A.
We present current and future constraints on equations of state for dark sector perturbations. The equations of state considered are those corresponding to a generalized scalar field model and time-diffeomorphism invariant ℒ(g) theories that are equivalent to models of a relativistic elastic medium and also Lorentz violating massive gravity. We de…
Suzaku observation of Be/X-ray binary pulsar EXO 2030+375
Naik, Sachindra; Jaisawal, Gaurava K.
We study the timing and spectral properties of Be/X-ray binary pulsar EXO 2030+375 using a Suzaku observation taken on 2012 May 23, during a less intense Type I outburst. Pulsations were clearly detected in the X-ray light curves at a barycentric period of 41.2852 s, which suggest that the pulsar is spinning-up. The pulse profiles were found to be…
Signature of the presence of a third body orbiting around XB 1916-053
Sanna, A.; Romano, P.; Di Salvo, T. +9 more
Context. The ultra-compact dipping source
Cosmic microwave background anisotropies in the timescape cosmology
Wiltshire, David L.; Nazer, M. Ahsan
We analyze the spectrum of cosmic microwave background (CMB) anisotropies in the timescape cosmology: a potentially viable alternative to homogeneous isotropic cosmologies without dark energy. We exploit the fact that the timescape cosmology is extremely close to the standard cosmology at early epochs to adapt existing numerical codes to produce C…
Detection of fundamental and first harmonic cyclotron line in X-ray pulsar Cep X-4
Naik, Sachindra; Jaisawal, Gaurava K.
We report the broad-band spectral properties of the X-ray pulsar Cep X-4 by using a Suzaku observation in 2014 July. The 0.8-70 keV spectrum was found to be well described by three continuum models - Negative and Positive power-law with Exponential cut-off (NPEX), high-energy cut-off power-law and CompTT models. Additional components such as a cyc…
X-Ray Fading and Expansion in the “Miniature Supernova Remnant” of GK Persei
Yamaguchi, H.; Uchiyama, Y.; Drake, J. J. +3 more
We report on a second epoch of Chandra X-ray imaging spectroscopy of the spatially resolved old nova remnant GK Persei. An ACIS-S3 observation of 97.4 ks was conducted in 2013 November after a lapse of 13.8 yr from the last visit in 2000. The X-ray emitting nebula appeared more faint and patchy compared with the first epoch. The flux decline was p…
Spatial distribution of ice blocks on Enceladus and implications for their origin and emplacement
Ingersoll, Andrew P.; Ewald, Shawn P.; Helfenstein, Paul +2 more
We have mapped the locations of over 100,000 ice blocks across the south polar region of Saturn's moon Enceladus, thus generating the first quantitative estimates of ice-block number density distribution in relation to major geological features. Ice blocks were manually identified and mapped from twenty of the highest resolution (4-25 m per pixel)…
Wave-like Formation of Hot Loop Arcades
Shestov, S.; Kuzin, S.; Zimovets, I. +2 more
We present observations of hot arcades made with the Mg XII spectroheliograph onboard the CORONAS-F mission, which provides monochromatic images of hot plasma in the Mg XII 8.42 Å resonance line. The arcades were observed to form above the polarity inversion line between active regions NOAA 09847 and 09848 at four successive episodes: at 09:18, 14…