Mass Equilibration and Fluctuations in the Angular Momentum Dependent Dynamics of Heavy Element Synthesis Reactions

ABSTRACT We present time-lapse spectroscopy of a classical nova explosion commencing 9 d after discovery. These data reveal the appearance of a transient feature in Fe ii and [O i]. We explore different models for this feature and conclude that it is best explained by a circumbinary disc shock-heated following the classical nova event. Circumbinary discs may play an important role in novae in accounting for the absorption systems known as transient heavy element absorption (THEA), the transfer of angular momentum, and the possible triggering of the nova event itself.

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Solar oscillations

Proceedings of the International Astronomical Union ◽

10.1017/s1743921309029135 ◽

2008 ◽

Vol 4 (S257) ◽

pp. 83-93

Author(s):

H. M. Antia

Keyword(s):

Angular Momentum ◽

Solar Cycle ◽

Momentum Transfer ◽

Rotation Rate ◽

Heavy Element ◽

Stellar Structure ◽

Solar Oscillations ◽

Element Abundances ◽

Solar Structure ◽

Structure And Dynamics

AbstractStudy of solar oscillations has provided us detailed information about solar structure and dynamics. These in turn provide a test of theories of stellar structure and evolution as well as theories of angular momentum transfer and dynamo. Some of these results about the solar structure and its implication on the recent revision of heavy element abundances are described. Apart from these the solar cycle variations in the rotation rate and its gradients are also discussed.

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Characterizing the mechanism(s) of heavy element synthesis reactions

EPJ Web of Conferences ◽

10.1051/epjconf/201613104003 ◽

2016 ◽

Vol 131 ◽

pp. 04003 ◽

Cited By ~ 1

Author(s):

Walter Loveland

Keyword(s):

Heavy Element ◽

Synthesis Reactions

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Distribution of R- and S-Process Elements in the Galactic Halo

Symposium - International Astronomical Union ◽

10.1017/s0074180900035555 ◽

1988 ◽

Vol 132 ◽

pp. 501-506

Author(s):

C. Sneden ◽

C. A. Pilachowski ◽

K. K. Gilroy ◽

J. J. Cowan

Keyword(s):

Heavy Element ◽

Galactic Halo ◽

Low Noise ◽

Heavy Elements ◽

Process Synthesis ◽

Element Abundances ◽

Halo Stars ◽

Abundance Patterns ◽

R Process ◽

Process Elements

Current observational results for the abundances of the very heavy elements (Z>30) in Population II halo stars are reviewed. New high resolution, low noise spectra of many of these extremely metal-poor stars reveal general consistency in their overall abundance patterns. Below Galactic metallicities of [Fe/H] Ã −2, all of the very heavy elements were manufactured almost exclusively in r-process synthesis events. However, there is considerable star-to-star scatter in the overall level of very heavy element abundances, indicating the influence of local supernovas on element production in the very early, unmixed Galactic halo. The s-process appears to contribute substantially to stellar abundances only in stars more metal-rich than [Fe/H] Ã −2.

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Variation of Heavy Element Lines in the Ap Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100080623 ◽

1976 ◽

Vol 32 ◽

pp. 311-320 ◽

Cited By ~ 1

Author(s):

I.A. Aslanov ◽

Yu. S. Rustamov ◽

M. Kowalski

Keyword(s):

Heavy Element ◽

Ap Stars

SummaryLines of U II were found in the spectrograms of the Ap stars HR 465, 17 Com A and HD 224801. Pm II lines were found in HR 465. These lines vary in intensity in HR 465 with a period of 6h41m, in 17 Com A of 71m, and in HD 224801 of 6h.

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Energy-filtered imaging of polymer microstructure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163277 ◽

1996 ◽

Vol 54 ◽

pp. 162-163

Author(s):

K. Siangchaew ◽

J. Bentley ◽

M. Libera

Keyword(s):

Energy Loss ◽

Heavy Element ◽

Spectroscopic Imaging ◽

Data Set ◽

Polymer Microstructure ◽

Entire Energy ◽

Staining Methods ◽

Spectrum Imaging ◽

Resolution Data

Energy-filtered electron-spectroscopic TEM imaging provides a new way to study the microstructure of polymers without heavy-element stains. Since spectroscopic imaging exploits the signal generated directly by the electron-specimen interaction, it can produce richer and higher resolution data than possible with most staining methods. There are basically two ways to collect filtered images (fig. 1). Spectrum imaging uses a focused probe that is digitally rastered across a specimen with an entire energy-loss spectrum collected at each x-y pixel to produce a 3-D data set. Alternatively, filtering schemes such as the Zeiss Omega filter and the Gatan Imaging Filter (GIF) acquire individual 2-D images with electrons of a defined range of energy loss (δE) that typically is 5-20 eV.

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