1,677 research outputs found
Exploring the Implications of Monetary Policy Normalisation for Irish Mortgage Arrears. Quarterly Economic Commentary Special Article, Spring 2019.
The current level of the monetary policy rate in the Eurozone is low both by international and historical standards and will likely rise over the coming years. In this Article we consider what the impact of a rise in ECB policy rates would mean for the Irish mortgage market. First, we examine the structure of the Irish mortgage market in terms of interest rate contract types and explore the link between the mortgage rate and the policy rate. Second, we draw out the results of policy modelling linking arrears and interest rates using a model put forward in Slaymaker et al. (2019). We then use this model to provide some further scenarios exploring the impact of interest rate rises on the arrears rate for particular groups of Irish households. Our findings suggest a 25 basis point increase in the policy rate would lead to a 0.1 percentage point increase in new missed mortgage payments. While households are in a better economic position to withstand policy rate increases given the recovery in the labour market and in house prices, rate rises would lead to payments rising faster than long-term income growth. Younger, lower income households who are at an earlier stage in their mortgage contract are more at risk, as are households on tracker interest rates who have a contractual pass-through from the policy rate to the lending rate
Integrated regional vulnerability assessment of government services to climate change
© Emerald Group Publishing Limited. Purpose – This paper aims to describe the conduct and outcomes of an integrated assessment (IA) of the vulnerability to climate change of government service provision at regional scale in New South Wales, Australia. The assessment was co-designed with regional public sector managers to address their needs for an improved understanding of regional vulnerabilities to climate change and variability. Design/methodology/approach – The study used IA of climate change impacts through a complex adaptive systems approach incorporating social learning and stakeholder-led research processes. Workshops were conducted with stakeholders from NSW government agencies, state-owned corporations and local governments representing the tourism, water, primary industries, human settlements, emergency management, human health, infrastructure and natural landscapes sectors. Participants used regional socioeconomic profiling and climate projections to consider the impacts on and the need to adapt community service provision to future climate. Findings – Many sectors are currently experiencing difficulty coping with changes in regional demographics and structural adjustment in the economy. Climate change will result in further impacts on already vulnerable systems in the forms of resource conflicts between expanded human settlements, the infrastructure that supports them and the environment (particularly for water); increased energy costs; and declining agricultural production and food security. Originality/value – This paper describes the application of meta-analysis in climate change policy research and frames climate change as a problem of environmental pollution and an issue of development and social equity
The Clusters AgeS Experiment (CASE). I. V209 omega Cen - An Eclipsing Post-Common Envelope Binary in the Globular Cluster omega Cen
We use photometric and spectroscopic observations of the detached eclipsing
binary V209 omega Cen to derive the masses, radii, and luminosities of the
component stars. The system exhibits total eclipses and, based on the measured
systemic velocity and the derived distance, is a member of the globular cluster
omega Cen. We obtain 0.945 +/- 0.043 Msun, 0.983 +/- 0.015 Rsun and 6.68 +/-
0.88 Lsun for the cooler, but larger and more luminous primary component. The
secondary component has 0.144 +/- 0.008 Msun, 0.425 +/- 0.008 Rsun and 2.26 +/-
0.28 Lsun. The effective temperatures are estimated at 9370 K for the primary
and at 10866 K for the secondary. On the color-magnitude diagram of the
cluster, the primary component occupies a position between the tip of the blue
straggler region and the extended horizontal branch while the secondary
component is located close to the red border of the area occupied by hot
subdwarfs. However, its radius is too large and its effective temperature is
too low for it to be an sdB star. We propose a scenario leading to the
formation of a system with such unusual properties with the primary component
``re-born'' from a former white dwarf which accreted a new envelope through
mass transfer from its companion. The secondary star has lost most of its
envelope while starting its ascent onto the sub-giant branch. It failed to
ignite helium in its core and is currently powered by a hydrogen burning shell.Comment: 24 pages, 9 figures, AJ, in pres
First Attempt at Spectroscopic Detection of Gravity Modes in a Long-Period Pulsating Subdwarf B Star -- PG 1627+017
In the first spectroscopic campaign for a PG 1716 variable (or long-period
pulsating subdwarf B star), we succeeded in detecting velocity variations due
to g-mode pulsations at a level of 1.0-1.5 km/s.The observations were obtained
during 40 nights on 2-m class telescopes in Arizona, South Africa,and
Australia. The target,PG1627+017, is one of the brightest and largest amplitude
stars in its class.It is also the visible component of a post-common envelope
binary.Our final radial velocity data set includes 84 hours of time-series
spectroscopy over a time baseline of 53 days. Our derived radial velocity
amplitude spectrum, after subtracting the orbital motion, shows three potential
pulsational modes 3-4 sigma above the mean noise level, at 7201.0s,7014.6s and
7037.3s.Only one of the features is statistically likely to be real,but all
three are tantalizingly close to, or a one day alias of, the three strongest
periodicities found in the concurrent photometric campaign. We further
attempted to detect pulsational variations in the Balmer line amplitudes. The
single detected periodicity of 7209 s, although weak, is consistent with
theoretical expectations as a function of wavelength.Furthermore, it allows us
to rule out a degree index of l= 3 or l= 5 for that mode. Given the extreme
weakness of g-mode pulsations in these stars,we conclude that anything beyond
simply detecting their presence will require larger telescopes,higher
efficiency spectral monitoring over longer time baselines,improved longitude
coverage, and increased radial velocity precision.Comment: 39 pages, 9 figures, 4 tables, ApJ accepted. See postscript for full
abtrac
Hot Subdwarfs in Resolved Binaries
In the last decade or so, there have been numerous searches for hot subdwarfs
in close binaries. There has been little to no attention paid to wide binaries
however. The advantages of understanding these systems can be many. The stars
can be assumed to be coeval, which means they have common properties. The
distance and metallicity, for example, are both unknown for the subdwarf
component, but may be determinable for the secondary, allowing other properties
of the subdwarf to be estimated. With this in mind, we have started a search
for common proper motion pairs containing a hot subdwarf component. We have
uncovered several promising candidate systems, which are presented here.Comment: 6 pages, 4 figures. Proceedings of The Fourth Meeting on Hot Subdwarf
Stars and Related Objects held in China, 20-24 July 2009. Accepted for
publication in Astrophysics and Space Scienc
Interaction between Cape hake spawning and the circulation in the northern Benguela upwelling ecosystem
Cape hake in Namibian waters are demersal and mesopelagic spawners, spawning peaking offshore between 100 and 400 m deep, depending on local environmental conditions. The cross-shelf circulation, low-oxygen layers and mesoscale gyres are three important environmental factors influencing hake spawning behaviour and subsequent transport of the spawning products. Normally, hake spawn offshore near the bottom at depths of
150–400 m. However, during one cruise, spawning was concentrated below several subsurface mesoscale gyres, resulting in reduced dispersion of the eggs and larvae. When the low-oxygen layer above the bottom is pronounced, hake spawning has been observed close to the top of the layer at oxygen concentrations as low as 0.2–0.3 ml l-1. The relatively small size of the eggs and their high specific gravity make them ascend quite slowly from the spawning depths, 10–40 m per day. Consequently, hake eggs spawned deeper than 200 m hatch before they reach the upper mixed layer. The newly hatched larvae are relatively undeveloped, without functional eyes or mouth, and display little swimming activity during their first hours, but laboratory observations have revealed subsequent periods of downward swimming activity. Based on current field observations, on buoyancy measurements of eggs and larvae and on observed larval behaviour, it is concluded that hake eggs and larvae are transported onshore by features of the upwelling subsurface circulation that compensate for offshore movement of surface water. This may be the basic mechanism concentrating early juvenile hake nearshore. Spawning activity near the low-oxygen layer might be a behavioural adaptation to minimize egg predation, because few other species are expected to survive such low concentrations of oxygen.Keywords: buoyancy, eggs, larvae, recruitment processes, retention, vertical distributionAfrican Journal of Marine Science 2001, 23: 317–33
Magnetic fields in central stars of planetary nebulae?
Most of the planetary nebulae (PN) have bipolar or other non-spherically
symmetric shapes. The presence of a magnetic field in the central star may be
the reason for this lack of symmetry, but observational works published in the
literature have so far reported contradictory results.
We try to correlate the presence of a magnetic field with the departures from
the spherical geometry of the envelopes of planetary nebulae.
We determine the magnetic field from spectropolarimetric observations of ten
central stars of planetary nebulae. The results of the analysis of the
observations of four stars was previously presented and discussed in the
literature, while the observations of six stars, plus additional measurements
for a star previously observed, are presented here for the first time.
All our determinations of magnetic field in the central planetary nebulae are
consistent with null results. Our field measurements have a typical error bar
of 150-300 G. Previous spurious field detections obtained with FORS were
probably due to the use of different wavelength calibration solutions for
frames obtained at different position angles of the retarder waveplate.
Currently, there is no observational evidence for the presence of magnetic
fields with a strength of the order of hundreds Gauss or higher in the central
stars of planetary nebulae.Comment: 5 pages, 2 figures, accepted for publication by Astronomy and
Astrophysic
Oscillation frequencies and mode lifetimes in alpha Centauri A
We analyse our recently-published velocity measurements of alpha Cen A
(Butler et al. 2004). After adjusting the weights on a night-by-night basis in
order to optimize the window function to minimize sidelobes, we extract 42
oscillation frequencies with l=0 to 3 and measure the large and small frequency
separations. We give fitted relations to these frequencies that can be compared
with theoretical models and conclude that the observed scatter about these fits
is due to the finite lifetimes of the oscillation modes. We estimate the mode
lifetimes to be 1-2 d, substantially shorter than in the Sun.Comment: Accepted by Ap
Exomoon simulations
We introduce and describe our newly developed code that simulates light
curves and radial velocity curves for arbitrary transiting exoplanets with a
satellite. The most important feature of the program is the calculation of
radial velocity curves and the Rossiter-McLaughlin effect in such systems. We
discuss the possibilities for detecting the exomoons taking the abilities of
Extremely Large Telescopes into account. We show that satellites may be
detected also by their RM effect in the future, probably using less accurate
measurements than promised by the current instrumental developments. Thus, RM
effect will be an important observational tool in the exploration of exomoons.Comment: 5 pages, 2 figures with 9 figure panels, accepted by EM&
Mode identification from monochromatic amplitude and phase variations for the rapidly pulsating subdwarf B star EC 20338-1925
We obtain time-series spectrophotometry observations at the VLT with the aim
of partially identifying the dominant oscillation modes in the rapidly
pulsating subdwarf B star EC 20338-1925 on the basis of monochromatic amplitude
and phase variations. From the data gathered, we detect four previously known
pulsations with periods near 147, 168, 126 and 140 s and amplitudes between 0.2
and 2.3 % of the star's mean brightness. We also determine the atmospheric
parameters of EC 20338-1925 by fitting our non-LTE model atmospheres to an
averaged combined spectrum. The inferred parameters are Teff = 34,153+-94 K,
log g =5.966+-0.017 and log[N(He)/N(H)] = - 1.642+-0.022, where the uncertainty
estimates quoted refer to the formal fitting errors. Finally, we calculate the
observed monochromatic amplitudes and phases for the periodicities extracted
using least-squares fitting to the light curves obtained for each wavelength
bin. These observed quantities are then compared to the corresponding
theoretical values computed on the basis of dedicated model atmosphere codes
and also taking into account non-adiabatic effects. We find that the quality of
the data is sufficient to identify the dominant pulsation at 146.9 s as a
radial mode, while two of the lower amplitude periodicities must be low-degree
modes with l=0-2. This is the first time that monochromatic amplitudes and
phases have been used for mode identification in a subdwarf B star, and the
results are highly encouraging.Comment: 11 pages. Accepted for publication in Astronomy & Astrophysic
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