5,835 research outputs found
Expectation adjustment in the housing market: insights from the Scottish auction system
This paper examines price expectation adjustment of house buyers and sellers to rapid changes in the housing market using data from Scotland where houses are sold through 'first-price sealed-bid' auctions. These auctions provide more information on market signals, incentives and the behaviour of market participants than private treaty sales. This paper therefore provides a theoretical framework for analysing revealed preference data generated from these auctions. We specifically focus on the analysis of the selling to asking price difference, the 'bid-premium'. The bid-premium is shown to be affected by expectations of future price movements, market duration and high bidding frequency. The bid-premium reflects consumers' expectations, adapting to market conditions more promptly than asking price setting behaviour and final sale prices. The volatile conditions of the recent housing market bubble are fully reflected in the bid-premium, whereas the asking and sale prices are much less prone to rapid movements
Spatially resolved spectra of 3C galaxy nuclei
We present and discuss visible-wavelength long-slit spectra of four low
redshift 3C galaxies obtained with the STIS instrument on the Hubble Space
Telescope. The slit was aligned with near-nuclear jet-like structure seen in
HST images of the galaxies, to give unprecedented spatial resolution of the
galaxy inner regions. In 3C 135 and 3C 171, the spectra reveal clumpy emission
line structures that indicate outward motions of a few hundred km s
within a centrally illuminated and ionised biconical region. There may also be
some low-ionisation high-velocity material associated with 3C 135. In 3C 264
and 3C 78, the jets have blue featureless spectra consistent with their
proposed synchrotron origin. There is weak associated line emission in the
innermost part of the jets with mild outflow velocity. These jets are bright
and highly collimated only within a circumnuclear region of lower galaxy
luminosity, which is not dusty. We discuss the origins of these central regions
and their connection with relativistic jets.Comment: 15 pages incl Tables, 12 diagrams, To appear in A
Extended X-ray emission in radio galaxies: the peculiar case of 3C 305
Extended X-ray structures are common in Active Galactic Nuclei (AGNs). Here
we present the first case of a Compact Steep Spectrum (CSS) radio galaxy, 3C
305, in which the X-ray radiation appears to be associated with the optical
emission line region, dominated by the [O III]5007. On the basis of a
morphological study, performed using the comparison between the X-rays, the
optical and the radio band, we argue that the high energy emission has a
thermal nature and it is not directly linked to the radio jet and hotspots of
this source. Finally, we discuss the origin of the extended X-ray structure
connected with the optical emission line region following two different
interpretations: as due to the interaction between matter outflows and
shock-heated environment gas, or as due to gas photoionized by nuclear
emission.Comment: 5 pages, 2 figures, Accepted for publication in The ApJL Comments:
references and affilitations correcte
Solar Physics - Plasma Physics Workshop
A summary of the proceedings of a conference whose purpose was to explore plasma physics problems which arise in the study of solar physics is provided. Sessions were concerned with specific questions including the following: (1) whether the solar plasma is thermal or non-themal; (2) what spectroscopic data is required; (3) what types of magnetic field structures exist; (4) whether magnetohydrodynamic instabilities occur; (5) whether resistive or non-magnetohydrodynamic instabilities occur; (6) what mechanisms of particle acceleration have been proposed; and (7) what information is available concerning shock waves. Very few questions were answered categorically but, for each question, there was discussion concerning the observational evidence, theoretical analyses, and existing or potential laboratory and numerical experiments
Deep Impact Mission to Tempel 1 Favours New Explosive Cosmogony of Comets
The assumption that short-period (SP) comets are fragments of massive icy
envelopes of Ganymede-like bodies saturated by products of ice electrolysis
that underwent global explosions provides a plausible explanation of all known
manifestations of comets, including the jet character of outflows, the presence
of ions in the vicinity of the nucleus, the bursts and splitting of cometary
nuclei, etc., with solar radiation initiating burning of the products of
electrolysis in the nucleus. As shown persuasively by numerical simulation
carried out in hydrodynamic approximation, the shock wave initiated by the Deep
Impact (DI) impactor in the cometary ice saturated originally by the
electrolysis products 2H2 + O2 is capable of activating under certain
conditions exothermal reactions (of the type O2 + H2 + organics = H2O + CO +
HCN + other products of incomplete burning of organics including its light and
heavy pyrolyzed compounds, soot, etc.), which will slow down shock wave damping
(forced detonation) and increase many times the energy release. As a result,
the measured energetics of ejections and outflows from the crater have to
exceed the DI energetics. Analysis of different clusters of the DI experiment
data confirms these conclusions and expectations and thus it favours the
planetary origin of comets.Comment: 21 pages incluging 3 figure
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Exploring our practitioner and parent partnerships
The study presented here is underpinned by Froebel’s pedagogy and principles; acknowledging the importance and value of the relationship between children, family members and practitioners, and the role of play as a central, integrating element in children’s development and learning (Froebel, c1826, trans 1912). For Froebel, parents and family members form the basis for a child’s understandings and interactions, which reiterates that an effective partnership essentially involves the engagement of parents and practitioners in order to support all children educationally, socially and emotionally
Rigidity of compact Riemannian spin Manifolds with Boundary
In this article, we prove new rigidity results for compact Riemannian spin
manifolds with boundary whose scalar curvature is bounded from below by a
non-positive constant. In particular, we obtain generalizations of a result of
Hang-Wang \cite{hangwang1} based on a conjecture of Schroeder and Strake
\cite{schroeder}.Comment: English version of "G\'eom\'etrie spinorielle extrins\`eque et
rigidit\'es", Corollary 6 in Section 3 added, to appear in Letters Math. Phy
The Jet of 3C 17 and the Use of Jet Curvature as a Diagnostic of the X-ray Emission Process
We report on the X-ray emission from the radio jet of 3C 17 from Chandra
observations and compare the X-ray emission with radio maps from the VLA
archive and with the optical-IR archival images from the Hubble Space
Telescope. X-ray detections of two knots in the 3C 17 jet are found and both of
these features have optical counterparts. We derive the spectral energy
distribution for the knots in the jet and give source parameters required for
the various X-ray emission models, finding that both IC/CMB and synchrotron are
viable to explain the high energy emission. A curious optical feature (with no
radio or X-ray counterparts) possibly associated with the 3C 17 jet is
described. We also discuss the use of curved jets for the problem of
identifying inverse Compton X-ray emission via scattering on CMB photons.Comment: 6 pages, 6 figure (3 in color), 4 tables, ApJ accepte
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