227 research outputs found
Time Use During Recessions
We use data from the American Time Use Survey (ATUS), covering both the recent recession and the pre-recessionary period, to explore how foregone market work hours are allocated to other activities over the business cycle. Given the short time series, it is hard to distinguish business cycle effects from low frequency trends by simply comparing time spent on a given category prior to the recession with time spent on that category during the recession. Instead, we identify the business cycle effects on time use using cross state variation with respect to the severity of the recessions. We find that roughly 30% to 40% of the foregone market work hours are allocated to increased home production. Additionally, 30% of the foregone hours are allocated to increased sleep time and increased television watching. Other leisure activities absorb 20% of the foregone market work hours. We use our evidence from the ATUS to calibrate and test the predictions of workhorse macroeconomic models with home production. We show that the quantitative implications of these models regarding the allocation of time over the business cycle matches reasonably well the actual behavior of households.
Letter of intent:Large Acceptance Hadron and Photon Detector for an Investigation of Pb-induced Reactions at the CERN SPS
Pion-Kaon Scattering near the Threshold in Chiral SU(2) Perturbation Theory
In the context of chiral SU(2) perturbation theory, pion-kaon scattering is
analysed near the threshold to fourth chiral order. The scattering amplitude is
calculated both in the relativistic framework and by using an approach similar
to heavy baryon chiral perturbation theory. Both methods lead to equivalent
results. We obtain relations between threshold parameters, valid to fourth
chiral order, where all those combinations of low-energy constants which are
not associated with chiral-symmetry breaking terms drop out. The remaining
low-energy constants can be estimated using chiral SU(3) symmetry.
Unfortunately, the experimental information is not precise enough to test our
low-energy theorems.Comment: 38 pages, 5 figures, PhD Thesis, references adde
Measurement of the Partial Cross Sections s(TT), s(LT) and [s(T)+epsilon*s(L)] of the p(e,e' pi+)n Reaction in the Delta(1232) Resonance
We report new precision p(e,e' pi+})n measurements in the Delta(1232)
resonance at Q2 = 0.127(GeV/c)2 obtained at the MIT-Bates Out-Of-Plane
scattering facility. These are the lowest, but non-zero, Q2 measurements in the
pi+ channel. The data offer new tests of the theoretical calculations,
particularly of the background amplitude contributions. The chiral effective
field theory and Sato-Lee model calculations are not in agreement with this
experiment
Investigation of the conjectured nucleon deformation at low momentum transfer
We report new precise H measurements at the
resonance at (GeV/c) using the MIT/Bates
out-of-plane scattering (OOPS) facility. The data reported here are
particularly sensitive to the transverse electric amplitude () of the
transition. Analyzed together with previous data yield
precise quadrupole to dipole amplitude ratios and and
for . They give credence to the conjecture of
deformation in hadronic systems favoring, at low , the dominance of
mesonic effects.Comment: 4 pages, 1figur
Lowest Q^2 Measurement of the gamma*p -> Delta Reaction: Probing the Pionic Contribution
To determine nonspherical angular momentum amplitudes in hadrons at long
ranges (low Q^2), data were taken for the p(\vec{e},e'p)\pi^0 reaction in the
Delta region at Q^2=0.060 (GeV/c)^2 utilizing the magnetic spectrometers of the
A1 Collaboration at MAMI. The results for the dominant transition magnetic
dipole amplitude and the quadrupole to dipole ratios at W=1232 MeV are:
M_{1+}^{3/2} = (40.33 +/- 0.63_{stat+syst} +/- 0.61_{model})
(10^{-3}/m_{\pi^+}),Re(E_{1+}^{3/2}/M_{1+}^{3/2}) = (-2.28 +/- 0.29_{stat+syst}
+/- 0.20_{model})%, and Re(S_{1+}^{3/2}/M_{1+}^{3/2}) = (-4.81 +/-
0.27_{stat+syst} +/- 0.26_{model})%. These disagree with predictions of
constituent quark models but are in reasonable agreement with lattice
calculations with non-linear (chiral) pion mass extrapolations, with chiral
effective field theory, and with dynamical models with pion cloud effects.
These results confirm the dominance, and general Q^2 variation, of the pionic
contribution at large distances.Comment: 6 pages, 3 figures, 1 tabl
Measurement of the Transverse-Longitudinal Cross Sections in the p (e,e'p)pi0 Reaction in the Delta Region
Accurate measurements of the p(e,e?p)pi0 reaction were performed at
Q^2=0.127(GeV/c)^2 in the Delta resonance energy region. The experiments at the
MIT-Bates Linear Accelerator used an 820 MeV polarized electron beam with the
out of plane magnetic spectrometer system (OOPS). In this paper we report the
first simultaneous determination of both the TL and TL? (``fifth" or polarized)
cross sections at low Q^{2} where the pion cloud contribution dominates the
quadrupole amplitudes (E2 and C2). The real and imaginary parts of the
transverse-longitudinal cross section provide both a sensitive determination of
the Coulomb quadrupole amplitude and a test of reaction calculations.
Comparisons with model calculations are presented. The empirical MAID
calculation gives the best overall agreement with this accurate data. The
parameters of this model for the values of the resonant multipoles are
|M_{1+}(I=3/2)|= (40.9 \pm 0.3)10^{-3}/m_pi, CMR= C2/M1= -6.5 \pm 0.3%,
EMR=E2/M1=-2.2 \pm 0.9%, where the errors are due to the experimental
uncertainties.Comment: 10 pages, 3 figures, minor corrections and addition
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