Search Publications
Local influence of magnetosheath plasma beta fluctuations on magnetopause reconnection
André, M.; Vaivads, A.; Rème, H. +2 more
We present observations from two subsolar Cluster magnetopause crossings under southward interplanetary magnetic field and strong mirror mode fluctuations in the magnetosheath. In both events the reconnection outflow jets show strong variations on the timescale of one minute. We show that at least some of the recorded variations are truly temporal…
Lithium Abundance in Solar-type Stars with Low Chromospheric Activity: Application to the Search for Maunder Minimum Analogs
Tytler, David; Lubin, Dan; Kirkman, David
We use measurements of lithium abundance to examine the evolutionary history of stars frequently believed to be in a Maunder minimum (MM) state due to their low chromospheric activity. In a sample whose main-sequence membership has been verified using Hipparcos parallax data, we find that stars with very low chromospheric activity log R'HK
Cold dust clumps in dynamically hot gas
Poglitsch, A.; Bernard, J. -P.; Reach, W. T. +27 more
Aims: We present clumps of dust emission from Herschel observations of the Large Magellanic Cloud (LMC) and their physical and statistical properties. We catalog cloud features seen in the dust emission from Herschel observations of the LMC, the Magellanic type irregular galaxy closest to the Milky Way, and compare these features with H i cat…
The Type Ib supernova 2010O: an explosion in a Wolf-Rayet X-ray binary?
Nelemans, Gijs; Voss, Rasmus; Nielsen, Mikkel T. B. +1 more
The Type Ib supernova 2010O was recently discovered in the interacting starburst galaxy Arp 299. We present an analysis of two archival Chandra X-ray observations of Arp 299 taken before the explosion and show that there is a transient X-ray source at a position consistent with the supernova. Due to the diffuse emission, the background is difficul…
V5116 Sgr: A disc-eclipsed SSS post-outburst nova?
Greiner, J.; Hernanz, M.; Sala, G. +1 more
Nova V5116 Sgr 2005 No. 2, discovered on 2005 July 4, was observed with XMM-Newton in March 2007, 20 months after the optical outburst. The X-ray spectrum showed that the nova had evolved to a pure supersoft X-ray source, indicative of residual H-burning on top of the white dwarf. The X-ray light-curve shows abrupt decreases and increases of the f…
New intrinsic-colour calibration for uvby- β photometry
Karataş, Yüksel; Schuster, William J.
A new intrinsic-colour calibration ((b-y)o-β) is presented for the uvby- β photometric system, making use of re-calibrated Hipparcos parallaxes and published reddening maps. This new calibration for (b-y)o-β, our Eq. (1), has been based upon stars with dHip<70pc in the photometric catalogues of Schuster and Niss…
EC 11481–2303—a peculiar subdwarf OB star revisited
Rauch, Thomas; Werner, Klaus; Kruk, Jeffrey W.
EC 11481–2303 is a peculiar, hot, high-gravity pre-white dwarf. Previous optical spectroscopy revealed that it is a sdOB star with Teff=41 790 K, log g=5.84, and He/H = 0.014 by number. We present an on-going spectral analysis by means of non-LTE model-atmosphere techniques based on high-resolution, high-S/N optical (VLT-UVES) and ultra…
When galaxies collide: understanding the broad absorption-line radio galaxy 4C +72.26
Jarvis, M. J.; Swinbank, A. M.; Rawlings, S. +2 more
We present a range of new observations of the `broad absorption-line radio galaxy' 4C +72.26 (z ~ 3.5), including sensitive rest-frame ultraviolet integral field spectroscopy using the Gemini/GMOS-N instrument and Subaru/CISCO K-band imaging and spectroscopy. We show that 4C +72.26 is a system of two vigorously star-forming galaxies superimposed a…
The Extended X-ray Nebula of PSR J1420-6048
Romani, Roger W.; Van Etten, Adam
The vicinity of the unidentified EGRET source 3EG J1420-6038 has undergone extensive study in the search for counterparts, revealing the energetic young pulsar PSR J1420-6048 and its surrounding wind nebula as a likely candidate for at least part of the emission from this bright and extended gamma-ray source. We report on new Suzaku observations o…
The Galaxy Alignment Effect in Abell 1689: Evolution, Radial, and Luminosity Dependence
De Propris, Roberto; Bañados, Eduardo; West, Michael J. +1 more
We measure alignments on scales of 1 Mpc h -1 71 for galaxies in Abell 1689 (z = 0.18) from an existing Hubble Space Telescope mosaic. We find evidence of galaxy alignment in the inner 500 h -1 71 kpc. The alignment appears to be stronger toward the center and is mostly present among the fainter galaxies…