Search Publications
Volcano-ice interactions in the Arsia Mons tropical mountain glacier deposits
Head, James W.; Marchant, David R.; Wilson, Lionel +1 more
Fan-shaped deposits (FSD) superposed on the sides of the Tharsis Montes volcanic edifices are widely interpreted to have been formed by cold-based glaciation during the Late Amazonian, a period when the Tharsis Montes were volcanically active. We survey the ∼166,000 km2 Arsia Mons FSD using new, high-resolution image and topography data…
Variation of the solar magnetic flux spectrum during solar cycle 23
Wang, J. X.; Jin, C. L.
By using the unique database of Solar and Heliospheric Observatory/Michelson Doppler Imager full disk magnetograms from September 1996 to January 2011, covering the entire solar cycle 23, we analyze the time-variability of the solar magnetic flux spectrum and study the properties of extended minimum of cycle 23. We totally identify 11.5 million ma…
Hubble Space Telescope Observations of the Afterglow, Supernova, and Host Galaxy Associated with the Extremely Bright GRB 130427A
Cenko, S. B.; Pian, E.; Kouveliotou, C. +13 more
We present Hubble Space Telescope (HST) observations of the exceptionally bright and luminous Swift gamma-ray burst (GRB), GRB 130427A. At z = 0.34, this burst affords an excellent opportunity to study the supernova (SN) and host galaxy associated with an intrinsically extremely luminous burst (E iso > 1054 erg): more lumi…
An Estimate of the Magnetic Field Strength Associated with a Solar Coronal Mass Ejection from Low Frequency Radio Observations
Ramesh, R.; Kathiravan, C.; Wang, T. J. +2 more
We report ground based, low frequency heliograph (80 MHz), spectral (85-35 MHz), and polarimeter (80 and 40 MHz) observations of drifting, non-thermal radio continuum associated with the "halo" coronal mass ejection that occurred in the solar atmosphere on 2013 March 15. The magnetic field strengths (B) near the radio source were estimated to be B…
IPHAS and the symbiotic stars. III. New discoveries and their IR spectral energy distributions
Munari, U.; Corradi, R. L. M.; Santander-García, M. +5 more
Context. The IPHAS Hα survey provides a rich database to search for emission-line sources in the northern Galactic plane.
Aims: We are systematically searching for symbiotic stars in the Milky Way using IPHAS. Our final goal, a complete census of this class of objects in the Galaxy, is a fundamental figure for discussing their overall propert…
Ultraluminous X-ray sources: a deeper insight into their spectral evolution
Wolter, Anna; Pintore, Fabio; Zampieri, Luca +1 more
We select a sample of nearby ultraluminous X-ray sources with long XMM-Newton observations and analyse all the available XMM-Newton data using both X-ray spectral fitting techniques and hardness-intensity diagrams. The sample includes IC 342 X-1, NGC 5204 X-1, NGC 5408 X-1, Holmberg IX X-1, Holmberg II X-1, NGC 1313 X-1, NGC 1313 X-2 and NGC 253 X…
Physics of saltation and sand transport on Titan: A brief review
Lorenz, Ralph D.
Key physical aspects of saltation and sand transport on Titan are reviewed, and the sensitivity of saltation parameters to assumptions about sand composition (most likely of 'heavy' organics) is explored. The possibility of significant triboelectric charging of sediments in Titan's low-conductivity environment is noted, and given Titan's low gravi…
Planetary period oscillations in Saturn's magnetosphere: Comparison of magnetic oscillations and SKR modulations in the postequinox interval
Dougherty, M. K.; Lamy, L.; Cowley, S. W. H. +1 more
We compare the properties of planetary period oscillations observed in Saturn kilometric radiation (SKR) and magnetospheric magnetic field data from Saturn equinox in August 2009 to July 2013. As shown previously, the southern and northern oscillation periods converged across equinox from ~10.8 h and ~10.6 h, respectively, during southern summer, …
Annihilation signals from asymmetric dark matter
Hardy, Edward; Lasenby, Robert; Unwin, James
In the simplest models of asymmetric dark matter (ADM) annihilation signals are not expected, since the DM is non-self-conjugate and the relic density of anti-DM is negligible. We investigate a new class of models in which a symmetric DM component, in the `low-mass' 1-10 GeV regime favoured for linking the DM and baryon asymmetries, is repopulated…
Chandra and XMM-Newton Study of the Supernova Remnant Kes 73 Hosting the Magnetar 1E 1841-045
Safi-Harb, Samar; Gotthelf, E. V.; Slane, Patrick O. +1 more
We present a Chandra and XMM-Newton study of the supernova remnant (SNR) Kes 73 hosting the anomalous X-ray pulsar 1E 1841-045. The Chandra image reveals clumpy structures across the remnant with enhanced emission along the western rim. The X-ray emission fills the radio shell and spatially correlates with the infrared image. The global X-ray spec…