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Title: Born again universe

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Publication Date:
Sponsoring Org.:
OSTI Identifier:
Grant/Contract Number:
SC0012012; 2015-037; 2015-038
Resource Type:
Journal Article: Published Article
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 97; Journal Issue: 4; Related Information: CHORUS Timestamp: 2018-02-02 15:21:04; Journal ID: ISSN 2470-0010
American Physical Society
Country of Publication:
United States

Citation Formats

Graham, Peter W., Kaplan, David E., and Rajendran, Surjeet. Born again universe. United States: N. p., 2018. Web. doi:10.1103/PhysRevD.97.044003.
Graham, Peter W., Kaplan, David E., & Rajendran, Surjeet. Born again universe. United States. doi:10.1103/PhysRevD.97.044003.
Graham, Peter W., Kaplan, David E., and Rajendran, Surjeet. 2018. "Born again universe". United States. doi:10.1103/PhysRevD.97.044003.
title = {Born again universe},
author = {Graham, Peter W. and Kaplan, David E. and Rajendran, Surjeet},
abstractNote = {},
doi = {10.1103/PhysRevD.97.044003},
journal = {Physical Review D},
number = 4,
volume = 97,
place = {United States},
year = 2018,
month = 2

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevD.97.044003

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  • We present a new quantum reaction field model, the electronic reaction field (ERF), which does not require the empirical specification of cavity shape and size. We demonstrate our approach on one of the simplest reaction field theories, the Born model for aqueous atomic ion solvation. The ERF model enforces complete solute{endash}solvent separability so that the solute wave function is optimized under the boundary condition that it is fully contained within the cavity. This model imposes the exact condition necessary for treating the solute quantum mechanically and the other as a macroscopic classical dielectric, and allows the testing of the primarymore » assumption in the dielectric continuum approximation that the molecular character of solvent is unimportant. We show that the Born theory for monovalent and divalent cations is consistent with ERF model enforcing full wave function containment, while strict solute{endash}solvent separability gives a poor description for anions of any valency. {copyright} {ital 1999 American Institute of Physics.}« less
  • A major challenge for the rest of this century is to develop a synthetic fuel industry able to contribute significantly without causing unacceptable environmental damage. An extensive range of design proposals and feasibility studies is exploring the commercial possibilities of converting coal and shale oil into usable fuels in order to determine the technically and economically best approach. All synthetic fuel processes involve hydrogenation by pyrolysis, direct action with hydrogen, or indirectly with water as a source of hydrogen. Synthetic fuels were not pursued in this country after World War II, but the Sasol coal-liquefaction plants based on the Germanmore » Fischer-Tropsch technology will produce half of South Africa's transportation fuel. (DCK)« less
  • We assessed splenic activity after splenectomy by interference phase microscopical examination of circulating red cells. Normal eusplenic children had a low number (<1%) of red cells with surface indentations or pits. About 20% of red cells of children who had electively been subjected to splenectomy for hematologic indications were pitted. Thirteen of 22 children who had had emergency splenectomy because of traumatic injury had a low percentage of pitted red cells, suggesting a return of splenic function. In five of these children a /sup 99m/Tc sulfur colloid scan demonstrated multiple nodules of recurrent splenic tissue. In contrast to the prevailingmore » opinion that splenosis is rare, we have found it to be a frequent occurrence. Return of splenic function may, in part, account for the low frequency with which overwhelming bacterial sepsis and meningitis have been documented after splenectomy for traumatic indications.« less
  • The planetary nebula A30 is believed to have undergone a very late thermal pulse resulting in the ejection of knots of hydrogen-poor material. Using multi-epoch Hubble Space Telescope images, we have detected the angular expansion of these knots and derived an age of 850{sup +280}{sub -150} yr. To investigate the spectral and spatial properties of the soft X-ray emission detected by ROSAT, we have obtained Chandra and XMM-Newton deep observations of A30. The X-ray emission from A30 can be separated into two components: a point source at the central star and diffuse emission associated with the hydrogen-poor knots and themore » cloverleaf structure inside the nebular shell. To help us assess the role of the current stellar wind in powering this X-ray emission, we have determined the stellar parameters and wind properties of the central star of A30 using a non-LTE model fit to its optical and UV spectra. The spatial distribution and spectral properties of the diffuse X-ray emission are highly suggestive that it is generated by the post-born-again and present fast stellar winds interacting with the hydrogen-poor ejecta of the born-again event. This emission can be attributed to shock-heated plasma, as the hydrogen-poor knots are ablated by the stellar winds, under which circumstances the efficient mass loading of the present fast stellar wind raises its density and damps its velocity to produce the observed diffuse soft X-rays. Charge transfer reactions between the ions of the stellar winds and material of the born-again ejecta have also been considered as a possible mechanism for the production of diffuse X-ray emission, and upper limits on the expected X-ray production by this mechanism have been derived. The origin of the X-ray emission from the central star of A30 is puzzling: shocks in the present fast stellar wind and photospheric emission can be ruled out, while the development of a new, compact hot bubble confining the fast stellar wind seems implausible.« less
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