Filming seismograms and related materials at the California Institute of Technology

As part of a world-wide effort to create an international earthquake data bank, Caltech's seismology archive has been organized, labeled, described, and microfilmed. It includes a wide variety of original records, documents, and printed materials relating to local and distant earthquakes. At present, we are filming significant seismograms prior to 1963; more than 50,000 records written between 1924 and 1935 have been filmed to date. Seismograms are the principal source of information about earthquakes and the earth's interior. These records, housed at Kresge Laboratory, the headquarters for Caltech's seismological network of stations, are important because they span so much of the period for which instrumental data exists. The early history of the Laboratory points up the role technology has played in the advancement of the science

The origins of nuclear astrophysics at Caltech

Shortly before the start of World War II, several theoretical physicists, including Hans Bethe and Carl von Weizsacker, advanced the idea that the sun derives it energy from nuclear reactions within its core. C. C. Lauritsen and William Fowler, nuclear physicists at Caltech's Kellogg Laboratory, were among the first experimentalists to appreciate the application of nuclear physics to stellar interiors. Post-war strategies for studying nuclear processes in the stars included an innovative series of unofficial, weekly seminars with Mt. Wilson astronomers at director Ira Bowen's house, the testing of Bethe's carbon cycle in Kellogg, and the collaboration with a diverse group of scientists ranging from cosmologist Fred Hoyle to astronomers Margaret and Geoffrey Burbidge. The events leading up to the publication of the 1957 paper by Fowler, Hoyle, Burbidge, and Burbidge, in The Reviews of Modern Physics, now regarded as a watershed in the history of nuclear astrophysics, are discussed. For his work in low-energy nuclear astrophysics, Fowler won the 1983 Nobel Prize in physics

Book Reviews

Urban Planning and Land Development Control Law. By Donald Hagman. This book seeks to distill, summarize and state textually the wisdom on planning and development control law collected and serves as a supplement to Mr. Hagman\u27s casebook. The reviewer criticizes the book for not more fully addressing zoning issues and the related problem of population concentration and dispersion as evidenced in the Golden v. Planning Board case. Public Workers and Public Unions. Edited by Sam Zagoria. This book brings together divergent views on on the growth of unions and other employee organizations, the impacts ad legal issues presented by collective bargaining, and the problems of the regulation of labor relations in the public sector

Efficacy of a four-week uphill sprint training intervention in field hockey players

Current evidence increasingly suggests that very short, supra-maximal bouts of exercise can have significant health and performance benefits. The majority of research conducted in the area however, uses laboratory-based protocols, which can lack ecological validity. The purpose of this study was to examine the effects of a high intensity sprint-training programme on hockey related performance measures. 14 semi-professional hockey players completed either a 4-week high intensity training (HIT) intervention, consisting of a total of six sessions HIT, which progressively increased in volume (n=7), or followed their normal training programme (Con; n=7). Straight-line sprint speed with and without a hockey stick and ball, and slalom sprint speed, with and without a hockey stick and ball were used as performance indicators. Maximal sprint speed over 22.9m was also assessed. Upon completion of the four-week intervention, straight-line sprint speed improved significantly in the HIT group (~3%), with no change in performance for the Con group. Slalom sprint speed, both with and without a hockey ball was not significantly different following the training programme in either group. Maximal sprint speed improved significantly (12.1%) in the HIT group, but there was no significant performance change in the Con group. The findings of this study indicate that a short period of HIT can significantly improve hockey related performance measures, and could be beneficial to athletes and coaches in field settings

Using EFT to analyze low-energy Compton scattering from protons and light nuclei

We discuss the application of an effective field theory (EFT) which incorporates the chiral symmetry of QCD to Compton scattering from the proton and deuteron. We describe the chiral EFT analysis of the proton Compton scattering database presented in our recent review (arXiv:1203.6834), which gives: alpha^{(p)}=10.5 +/- 0.5(stat) +/- 0.8(theory); beta^{(p)}= 2.7 +/- 0.5(stat) +/- 0.8(theory), for the electric and magnetic dipole polarizability of the proton. We also summarize the chiral EFT analysis of the world data on coherent Compton scattering from deuterium presented in arXiv:1203.6834. That yields: alpha^{(s)}=10.5 +/- 2.0(stat) +/- 0.8(theory); beta^{(s)}=3.6 +/- 1.0(stat) +/- 0.8(theory).Comment: 5 pages. Invited talk, presented by Phillips at the 11th Conference on the Intersections of Nuclear and Particle Physics (CIPANP 2012), St. Petersburg, FL, May 201

Compton scattering from the proton in an effective field theory with explicit Delta degrees of freedom

We analyse the proton Compton-scattering differential cross section for photon energies up to 325 MeV using Chiral Effective Field Theory and extract new values for the electric and magnetic polarisabilities of the proton. Our EFT treatment builds in the key physics in two different regimes: photon energies around the pion mass ("low energy") and the higher energies where the Delta(1232) resonance plays a key role. The Compton amplitude is complete at N4L0, O(e^2 delta^4), in the low-energy region, and at NLO, O(e^2 delta^0), in the resonance region. Throughout, the Delta-pole graphs are dressed with pi-N loops and gamma-N-Delta vertex corrections. A statistically consistent database of proton Compton experiments is used to constrain the free parameters in our amplitude: the M1 gamma-N-Delta transition strength b_1 (which is fixed in the resonance region) and the polarisabilities alpha and beta (which are fixed from data below 170 MeV). In order to obtain a reasonable fit we find it necessary to add the spin polarisability gammaM1 as a free parameter, even though it is, strictly speaking, predicted in chiral EFT at the order to which we work. We show that the fit is consistent with the Baldin sum rule, and then use that sum rule to constrain alpha+beta. In this way we obtain alpha=[10.65+/-0.35(stat})+/-0.2(Baldin)+/-0.3(theory)]10^{-4} fm^3, and beta =[3.15-/+0.35(stat)-/+0.2(Baldin)-/+0.3(theory)]10^{-4} fm^3, with chi^2 = 113.2 for 135 degrees of freedom. A detailed rationale for the theoretical uncertainties assigned to this result is provided.Comment: 36 pages, 15 figures Version 2 is shortened for publication; version 1 is more self-contained. Results section unchange

Comprehensive Study of Observables in Compton Scattering on the Nucleon

We present an analysis of $13$ observables in Compton scattering on the proton. Cross sections, asymmetries with polarised beam and/or targets, and polarisation-transfer observables are investigated for energies up to the $\Delta(1232)$ resonance to determine their sensitivity to the proton's dipole scalar and spin polarisabilities. The Chiral Effective Field Theory Compton amplitude we use is complete at N$^4$LO, $\mathcal{O(}e^2\delta^4)$, for photon energies $\omega\sim m_\pi$, and so has an accuracy of a few per cent there. At photon energies in the resonance region it is complete at NLO, $\mathcal{O}(e^2\delta^0)$, and so its accuracy there is about $20$\%. We find that for energies from pion-production threshold to about $250\;\mathrm{MeV}$, multiple asymmetries have significant sensitivity to presently ill-determined combinations of proton spin polarisabilities. We also argue that the broad outcomes of this analysis will be replicated in complementary theoretical approaches, e.g., dispersion relations. Finally, we show that below the pion-production threshold, $6$ observables suffice to reconstruct the Compton amplitude, and above it $11$ are required. Although not necessary for polarisability extractions, this opens the possibility to perform "complete" Compton-scattering experiments. An interactive Mathematica notebook, including results for the neutron, is available from [email protected] .Comment: 75 pages LaTeX2e (pdflatex) including 37 figures as .pdf files using includegraphics; minor corrections. Text-identical to published version but including the Online Supplement. Higher-resolution figures are available at http://home.gwu.edu/~hgrie/Compton/one-N-comprehensive-observables-delta4.v2.0.high-resolution-figures.tg