1,185 research outputs found
The Phonology of the Canadian Shift Revisited: Thunder Bay & Cape Breton
Previous accounts of the Canadian Shift, which have interpreted this diachronic process as a purely phonetic consequence of the low back LOT-THOUGHT vowel merger, have not clearly explained the strong connection between phonetic TRAP vowel retraction and the phonological process of the low back merger. This paper addresses this issue in several ways. Relying on the Modified Contrastive Specification theory (Dresher et al. 1994) and the Contrastive Hierarchy approach (Dresher 2009), two phonological frameworks, as well as phonetic insights from Vowel Dispersion theory (Liljencrants and Lindblom 1972) and Dispersion-Focalization theory (Schwartz et al. 1997, Schwartz et al. 2007), we propose that the catalyst of the Canadian Shift is a three-way merger of the PALM, LOT and THOUGHT lexical sets, in combination with a simultaneous change in the underlying feature specifications of the TRAP vowel. This results in a phonology that allows for the TRAP and DRESS vowels, in particular, to undergo the influence of the phonetic principles of dispersion and focalization, which lead to lowering and retraction in the acoustic vowel space. Comparison of data from speakers in Thunder Bay, Ontario, and Cape Breton, Nova Scotia, lends support to this hypothesis because the Cape Breton data reveals evidence of two concurrent phonological systems, despite no evidence of change over apparent time. Some Cape Breton speakers display the Ontario (i.e., inland Canada) Canadian Shifted vowel system, while others display a system that bears much greater resemblance to the Eastern New England non-shift dialect, where PALM merges with TRAP instead of LOT-THOUGHT. The current analysis thus predicts that the Canadian Shift or a similar change to the TRAP, DRESS, and KIT vowels will occur in any North American dialect where the PALM-LOT-THOUGHT merger occurs, unless an intervening phonological change alters the contrasts within the phonological system
Structure of 10N in 9C+p resonance scattering
The structure of exotic nucleus 10N was studied using 9C+p resonance
scattering. Two L=0 resonances were found to be the lowest states in 10N. The
ground state of 10N is unbound with respect to proton decay by 2.2(2) or 1.9(2)
MeV depending on the 2- or 1- spin-parity assignment, and the first excited
state is unbound by 2.8(2) MeV.Comment: 6 pages, 4 figures, 1 table, submitted to Phys. Lett.
Nuclear structure beyond the neutron drip line: the lowest energy states in He via their T=5/2 isobaric analogs in Li
The level structure of the very neutron rich and unbound He nucleus has
been the subject of significant experimental and theoretical study. Many recent
works have claimed that the two lowest energy He states exist with spins
and and widths on the order of hundreds of keV.
These findings cannot be reconciled with our contemporary understanding of
nuclear structure. The present work is the first high-resolution study with low
statistical uncertainty of the relevant excitation energy range in the
He system, performed via a search for the T=5/2 isobaric analog states
in Li populated through He+p elastic scattering. The present data show
no indication of any narrow structures. Instead, we find evidence for a broad
state in He located approximately 3 MeV above the neutron
decay threshold
Combined roles for breeding synchrony, habitat and scale as predictors of extrapair paternity
publishedVersio
Extreme alpha-clustering in the 18O nucleus
The structure of the 18O nucleus at excitation energies above the alpha decay
threshold was studied using 14C+alpha resonance elastic scattering. A number of
states with large alpha reduced widths have been observed, indicating that the
alpha-cluster degree of freedom plays an important role in this N not equal Z
nucleus. However, the alpha-cluster structure of this nucleus is very different
from the relatively simple pattern of strong alpha-cluster quasi-rotational
bands in the neighboring 16O and 20Ne nuclei. A 0+ state with an alpha reduced
width exceeding the single particle limit was identified at an excitation
energy of 9.9+/-0.3 MeV. We discuss evidence that states of this kind are
common in light nuclei and give possible explanations of this feature.Comment: 4 pages, 2 figures, 1 table. Resubmission with minor changes for
clarity, including removal of one figur
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