877 research outputs found
Spin-dominated waveforms for unequal mass compact binaries
We derive spin-dominated waveforms (SDW) for binary systems composed of
spinning black holes with unequal masses (less than 1:30). Such systems could
be formed by an astrophysical black hole with a smaller black hole or a neutron
star companion; and typically arise for supermassive black hole encounters. SDW
characterize the last stages of the inspiral, when the larger spin dominates
over the orbital angular momentum (while the spin of the smaller companion can
be neglected). They emerge as a double expansion in the post-Newtonian
parameter and the ratio of the orbital angular momentum
and dominant spin. The SDW amplitudes are presented to
() orders, while the phase of the gravitational waves to
() orders (omitting the highest order mixed terms). To
this accuracy the amplitude includes the (leading order) spin-orbit
contributions, while the phase the (leading order) spin-orbit, self-spin and
mass quadrupole-monopole contributions. While the SDW hold for any mass ratio
smaller than 1:30, lower bounds for the mass ratios are derived from the best
sensitivity frequency range expected for Advanced LIGO (giving 1:140), the
Einstein Telescope (), the LAGRANGE () and
LISA missions (), respectively.Comment: 14 pages, 2 figures, 5 tables, published versio
Poisson limit of an inhomogeneous nearly critical INAR(1) model
An inhomogeneous first--order integer--valued autoregressive (INAR(1))
process is investigated, where the autoregressive type coefficient slowly
converges to one. It is shown that the process converges weakly to a Poisson or
a compound Poisson distribution.Comment: Latex2e pdfeTex Version 3, 22 pages, submitted to ACTA Sci. Math.
(Szeged
Photo-Met: a non-parametric method for estimating stellar metallicity from photometric observations
Getting spectra at good signal-to-noise ratios takes orders of magnitudes
more time than photometric observations. Building on the technique developed
for photometric redshift estimation of galaxies, we develop and demonstrate a
non-parametric photometric method for estimating the chemical composition of
galactic stars. We investigate the efficiency of our method using
spectroscopically determined stellar metallicities from SDSS DR7. The technique
is generic in the sense that it is not restricted to certain stellar types or
stellar parameter ranges and makes it possible to obtain metallicities and
error estimates for a much larger sample than spectroscopic surveys would
allow. We find that our method performs well, especially for brighter stars and
higher metallicities and, in contrast to many other techniques, we are able to
reliably estimate the error of the predicted metallicities.Comment: 5 pages, 4 figures, accepted for publication in A
A preliminary report on the early Oligocene (Rupelian, Kiscellian) selachians from the Kiscell Formation (Buda Mts, Hungary), with the re-discovery of Wilhelm Weilerâs shark teeth
An Early Oligocene (Rupelian, Kiscellian), partially published shark tooth material,
unearthed from the Kiscell Clay (Budapest, Hungary) is shortly reviewed here. A few shark taxa
have been published by Wilhelm Weiler in 1933 and 1938, and some of this material was re-dis-
covered in the Hungarian Natural History Museum. Th
e here described shark taxa are
Notorynchus
primigenius
,
Hexanchus agassizi
,
Heptranchias howelli
,
Araloselachus cuspidatus
,
Carcharias
spp.,
Carcharoides catticus
,
Isurolamna gracilis
,
Otodus
(
Carcharocles
)
angustidens
,
Alopias
cf.
exigua
,
Car-
charhinus
sp., and
Physogaleus latus
. Th
e results indicate a relatively diverse shark fauna with mixed
ecological needs. Th
e revised list of the local selachian taxa suggests that a detailed review of all
Kiscell shark material (collected in the last century), placed both in public and private collections,
is needed. With 73 fi
gures, 1 table and 1 appendix
Flexural basin reworked by salt-related pull-apart structures: the Adony Basin
Abstract
Several main tectonic lineaments originating in the Alps and Dinarides merge in Central Hungary to form the Mid-Hungarian Shear Zone. As these structures are hidden beneath sub-basins of the Neogene Pannonian Basin, it has long been debated whether the tectonic style of the shear zone is mainly contractional or strike-slip. New 3D seismic data allowed a detailed analysis of one of these sub-basins, the Adony Basin, located south of Budapest. Its evolution is linked to the tectonics between the southern Tisza unit of European passive margin affinity, the northern ALCAPA block with Alpine affinity, and sheared remnants of Dinaric units in between. During the Oligocene and Early to Middle Miocene, a flexural basin related to the convergent thrusting of Dinaric- and ALCAPA-derived units was developed. On the southern side, N-NW verging thrust sheets were observed. On the opposite front, Triassic carbonates of ALCAPA were thrust several kilometres above Palaeogene formations to the SW. Dextral transpression is assumed for the Middle Miocene. Local deposition of Middle Miocene salt in the basin formed a detachment surface. Late Miocene sinistral strike-slip faulting resulted in a pull-apart basin above that part of the earlier flexural basin that has not been overthrust. The margins of the basin coincided with the fronts of earlier thrusts. Faults on the basin margins partly detached on the salt, decoupling the supra-salt basin fill from the underlying formations. Within the pull-apart basin, gravity sliding on the steep margins resulted in salt welds, detachment and roll-over folds
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