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Broad absorption features in wind-dominated ultraluminous X-ray sources?
Middleton, Matthew J.; Roberts, Timothy P.; Walton, Dominic J. +1 more
The luminosities of ultraluminous X-ray sources (ULXs) require an exotic solution with either supercritical accretion modes on to stellar-mass black holes or subcritical accretion on to intermediate-mass black holes (IMBHs) being invoked. Discriminating between the two is non-trivial due to the present lack of a direct mass measurement. A key expe…
Azimuthally resolved X-ray spectroscopy to the edge of the Perseus Cluster
Simionescu, A.; Fabian, A. C.; Allen, S. W. +9 more
We present the results from extensive, new observations of the Perseus Cluster of galaxies, obtained as a Suzaku Key Project. The 85 pointings analysed span eight azimuthal directions out to 2° = 2.6 Mpc, to and beyond the virial radius r200 ∼ 1.8 Mpc, offering the most detailed X-ray measurements of the intracluster medium (ICM) at lar…
Deflected propagation of a coronal mass ejection from the corona to interplanetary space
Wang, Yuming; Shen, Fang; Shen, Chenglong +2 more
Among various factors affecting the space weather effects of a coronal mass ejection (CME), its propagation trajectory in the interplanetary space is an important one determining whether and when the CME will hit the Earth. Many direct observations have revealed that a CME may not propagate along a straight trajectory in the corona, but whether or…
Wiggly whipped inflation
Starobinsky, Alexei A.; Hazra, Dhiraj Kumar; Smoot, George F. +1 more
Motivated by BICEP2 results on the CMB polarization B-mode which imply primordial gravitational waves are produced when the Universe has the expansion rate of about H ≈ 1014 GeV, and by deviations from a smooth power-law behavior for multipoles ℓ <50 in the CMB temperature anisotropy power spectrum found in the WMAP and Planck experi…
The Radiated Energy Budget of Chromospheric Plasma in a Major Solar Flare Deduced from Multi-wavelength Observations
Chamberlin, Phillip C.; Milligan, Ryan O.; Kerr, Graham S. +7 more
This paper presents measurements of the energy radiated by the lower solar atmosphere, at optical, UV, and EUV wavelengths, during an X-class solar flare (SOL2011-02-15T01:56) in response to an injection of energy assumed to be in the form of nonthermal electrons. Hard X-ray observations from RHESSI were used to track the evolution of the paramete…
Interstellar chemistry of nitrogen hydrides in dark clouds
Maret, S.; Hily-Blant, P.; Pineau des Forêts, G. +3 more
Nitrogen, amongst the most abundant metals in the interstellar medium, has a peculiar chemistry that differs from those of carbon and oxygen. Recent observations of several nitrogen-bearing species in the interstellar medium suggest abundances in sharp disagreement with current chemical models. Although some of these observations show that some ga…
Uncovering the Putative B-star Binary Companion of the SN 1993J Progenitor
Van Dyk, Schuyler D.; Filippenko, Alexei V.; Chandra, Poonam +9 more
The Type IIb supernova (SN) 1993J is one of only a few stripped-envelope SNe with a progenitor star identified in pre-explosion images. SN IIb models typically invoke H envelope stripping by mass transfer in a binary system. For the case of SN 1993J, the models suggest that the companion grew to 22 M ⊙ and became a source of ultraviolet…
A rapid decrease of the hydrogen corona of Mars
Quemerais, E.; Bertaux, J. -L.; Chaufray, J. -Y. +4 more
Mars is believed to have lost much of its surface water 3.5 billion years ago, but the amounts that escaped into space and remain frozen in the crust today are not well known. Hydrogen atoms in the extended martian atmosphere, some of which escape the planet's gravity, can be imaged through scattered solar UV radiation. Hubble Space Telescope (HST…
Weighing "El Gordo" with a Precision Scale: Hubble Space Telescope Weak-lensing Analysis of the Merging Galaxy Cluster ACT-CL J0102-4915 at z = 0.87
Sifón, Cristóbal; Hughes, John P.; Barrientos, L. Felipe +5 more
We present a Hubble Space Telescope weak-lensing study of the merging galaxy cluster "El Gordo" (ACT-CL J0102-4915) at z = 0.87 discovered by the Atacama Cosmology Telescope (ACT) collaboration as the strongest Sunyaev-Zel'dovich decrement in its ~1000 deg2 survey. Our weak-lensing analysis confirms that ACT-CL J0102-4915 is indeed an e…
Rejecting Proposed Dense Matter Equations of State with Quiescent Low-mass X-Ray Binaries
Guillot, Sebastien; Rutledge, Robert E.
Neutrons stars are unique laboratories for discriminating between the various proposed equations of state of matter at and above nuclear density. One sub-class of neutron stars—those inside quiescent low-mass X-ray binaries (qLMXBs)—produce a thermal surface emission from which the neutron star radius (R NS) can be measured, using the w…