72,237 research outputs found
G+++ and Brane Solutions
We demonstrate that the very extended G+++ group element of the form
describes the usual BPS, electric, single brane solutions found in G+++
theories.Comment: One new equation, added references, corrected typos and minor
changes, 42 pages, 6 figures, LaTeX2
Is 4U 0114+65 an eclipsing HMXB?
We present the pulsation and spectral characteristics of the HMXB 4U 0114+65
during a \emph{Suzaku} observation covering the part of the orbit that included
the previously known low intensity emission of the source (dip) and the egress
from this state. This dip has been interpreted in previous works as an X-ray
eclipse. Notably, in this Suzaku observation, the count rate during and outside
the dip vary by a factor of only 2-4 at odds with the eclipses of other HMXBs,
where the intensity drops upto two orders of magnitude. The orbital intensity
profile of 4U 0114+65 is characterized by a narrow dip in the RXTE-ASM (2-12
\rm{keV}) light curve and a shallower one in the Swift-BAT (15-50 \rm{keV}),
which is different from eclipse ingress/egress behaviour of other HMXBs. The
time-resolved spectral analysis reveal moderate absorption column density
(N - 2-20 atoms ) and a relatively low
equivalent width ( 30 \rm{eV} \& 12 \rm{eV} of the iron K and
K lines respectively) as opposed to the typical X-ray spectra of HMXBs
during eclipse where the equivalent width is 1 \rm{keV}. Both XIS and
PIN data show clear pulsations during the dip, which we have further confirmed
using the entire archival data of the IBIS/ISGRI and JEM-X instruments onboard
\emph{INTEGRAL}. The results we presented question the previous interpretation
of the dip in the light curve of 4U 0114+65 as an X-ray eclipse. We thus
discuss alternative interpretations of the periodic dip in the light curve of
4U 0114+65.Comment: 16 pages, 7 figures, 1 table, Accepted in MNRA
Relativistic correlation correction to the binding energies of the ground configuration of Beryllium-like, Neon-like, Magnesium-like and Argon-like ions
Total electronic correlation correction to the binding energies of the
isoelectronic series of Beryllium, Neon, Magnesium and Argon, are calculated in
the framework of relativistic multiconfiguration Dirac-Fock method. Convergence
of the correlation energies is studied as the active set of orbitals is
increased. The Breit interaction is treated fully self-consistently. The final
results can be used in the accurately determination of atomic masses from
highly charged ions data obtained in Penning-trap experiments.Comment: version soumise 3/08/200
The role of recent experience and weight on hen's agonistic behaviour during dyadic conflict resolution.
Recent victory or defeat experiences and 2-hour familiarity with the meeting place were combined with size differences in order to better understand their effects on the behaviour leading to the establishment of dyadic dominance relationships between hens not previously acquainted with each other. Three kinds of encounters were videotaped: (i) a previous winner unfamiliar with the meeting place met a previous loser familiar for 2 hours with the meeting place (n = 12 dyads); (ii) as in (i) but both were unfamiliar with the meeting place (n=12); (iii) as in (i) but the previous winner was familiar with the meeting place while the previous loser was unfamiliar (n=13). The weight asymmetry was combined with these three types of encounters by selecting hens of various weight differences: in 29 dyads the recent loser was heavier than the recent winner and in 8 dyads it was the reverse. Recent experience had a major influence upon both agonistic behaviour and dominance outcome. Hens that were familiar with the meeting site initiated attacks more frequently than their unfamiliar opponent but did not win significantly more often. Recent experience and site familiarity could be used to identify 80% of future initiators. Once the first aggressive behaviour had been initiated, it led to victory of its initiator in 92% of cases. Weight was not found to influence agonistic behaviour nor dominance outcome. However, hens with superior comb and wattles areas won significantly more initial meetings than opponents with smaller ones. In the final encounters, victory also went more frequently to the bird showing larger comb and wattles, which happened also to be the previous dominant in a majority of cases. The use of higher-order partial correlations as an ex post facto control for comb and wattles indicates that they were not influential upon agonistic behaviour nor on dominance outcome, but were simply co-selected with the selection of victorious and defeated birds in the first phase of the experiment designed to let hens acquire recent victory/defeat experience
The role of hen's weight and recent experience on dyadic conflict outcome
This study simultaneously varied experiences of recent victory or defeat, 2-hour familiarity with the meeting place, and hen weight in order to understand their combined effects on the establishment of dyadic dominance relationships between hens not previously acquainted with each other. Three kinds of encounters were arranged: (i) a previous winner unfamiliar with the meeting place met a previous loser familiar with the meeting place (n =28 dyads); (ii) a previous winner met a previous loser, both unfamiliar with the meeting place (n=27); (iii) a previous winner familiar with the meeting place encountered a previous loser unfamiliar with the meeting place (n=28). The weight asymmetry was combined with these three types of encounters by selecting hens showing various weight differences, in favour of the recent loser in 54 dyads and of the recent winner in 29 dyads. Results indicate that recent victory or defeat experience significantly affected the outcome. Even an important weight asymmetry, or familiarity with the meeting place were not sufficient for a hen recently defeated to overcome an opponent that was previously victorious. A 2-hour period of familiarization with the meeting place did not provide any significant advantage over unfamiliarity. Although a significant relationship was found to exist between comb and wattles areas and the initial and final statuses, examination of partial correlations indicates that the influence was from initial status to final status, rather than from comb and wattles to final status. These results suggest that more importance should be attributed to recent social experience in comparison to intrinsic factors in determining dyadic dominance in the hen
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