Stochastic Gravitational Wave Measurements with Bar Detectors: Dependence of Response on Detector Orientation

The response of a cross-correlation measurement to an isotropic stochastic gravitational-wave background depends on the observing geometry via the overlap reduction function. If one of the detectors being correlated is a resonant bar whose orientation can be changed, the response to stochastic gravitational waves can be modulated. I derive the general form of this modulation as a function of azimuth, both in the zero-frequency limit and at arbitrary frequencies. Comparisons are made between pairs of nearby detectors, such as LIGO Livingston-ALLEGRO, Virgo-AURIGA, Virgo-NAUTILUS, and EXPLORER-AURIGA, with which stochastic cross-correlation measurements are currently being performed, planned, or considered.Comment: 17 pages, REVTeX (uses rcs, amsmath, hyperref, and graphicx style files), 4 figures (8 eps image files

Molecular Design Parameters of Anthraquinone Dyes for Guest-Host Liquid-Crystal Applications : Experimental and Computational Studies of Spectroscopy, Structure and Stability

A set of five anthraquinone dyes with bis(4-propylphenyl) substituent groups, connected via sulfide or amine linkages at the 1,5-positions or directly at the 2,6-positions, have been studied in solution by UV-vis spectroscopy and electrochemistry, allied with density functional theory calculations of structures, electronic transitions, and redox potentials. The visible transitions and redox potentials are shown to vary with the HOMO and LUMO energies, with the variation in both color and redox stability between the dyes being attributable principally to variations in the HOMOs located mainly on the substituents and outer anthraquinone rings. The calculated molecular structures and visible transition dipole moments are shown to vary subtly with substituent, giving variations in the molecular aspect ratios, minimum moment of inertia axes, and transition dipole moment vector orientations that can rationalize the alignment trends reported in the literature for such anthraquinone dyes in liquid crystal hosts, showing why 1,5-disulfide and 2,6-diphenyl substituents give better designs than 1,5-diamine substituents. The computational approaches reported here are shown to give good matches with experimental trends, indicating that they may be used more generally to aid the rational molecular design of dyes for applications as guests in liquid crystal hosts

The Dwarf Novae of Shortest Period

We present observations of the dwarf novae GW Lib, V844 Her, and DI UMa. Radial velocities of H-alph yield orbital periods of 0.05332 +- 0.00002 d (= 76.78 m) for GW Lib and and 0.054643 +- 0.000007 d (= 78.69 m) for V844 Her. Recently, the orbital period of DI UMa was found to be only 0.054564 +- 0.000002 d (= 78.57 m) by Fried et al. (1999), so these are the three shortest orbital periods among dwarf novae with normal-abundance secondaries. GW Lib has attracted attention as a cataclysmic binary showing apparent ZZ Ceti-type pulsations of the white dwarf primary. Its spectrum shows sharp Balmer emission flanked by strong, broad Balmer absorption, indicating a dominant contribution by white-dwarf light. Analysis of the Balmer absorption profiles is complicated by the unknown residual accretion luminosity and lack of coverage of the high Balmer lines. Our best-fit model atmospheres are marginally hotter than the ZZ Ceti instability strip, in rough agreement with recent ultraviolet results from HST. The spectrum and outburst behavior of GW Lib make it a near twin of WZ Sge, and we estimate it to have a quiescent V absolute magnitude 12. Comparison with archival data reveals proper motion of 65 +- 12 mas/yr. The mean spectrum of V844 Her is typical of SU UMa dwarf novae. We detected superhumps in the 1997 May superoutburst with superhump period = 0.05597 +- 0.00005 d. The spectrum of DI UMa appears normal for a dwarf nova near minimum light. These three dwarf novae have nearly identical short periods but completely dissimilar outburst characteristics. We discuss possible implications.Comment: Accepted for publication in Publications of the Astronomical Society of the Pacific; 16 pages, 6 figure

1923-01-08, Letter from Linn County (Kansas) Jefferson Highway Association, to its Members

Copy of typewritten letter from Linn County (Kansas) Jefferson Highway Association, to its Member

The Ursinus Weekly, March 15, 1973

Ursinus Board of Directors meets in regular Spring session; Discusses tax proposals, committee reports, appointments • USGA fills vacancies; 3 new members elected • USGA secures bike racks; readies for J-Board elections • Old snack bar to be transformed by ProTheatre into acting workshop • Editorial: It depends on your point of view • Focus: David Mowere • WRUC, radio voice of Ursinus, on the air 12 hours a day • Fidler on the wax: New L.P. a delight for Traffic fans • Letters to the editor: Union head happy; Female uproar • Bearettes lose at regionals; West Chester drops Boydies • Water wonders end seasonhttps://digitalcommons.ursinus.edu/weekly/1100/thumbnail.jp

Reheating Temperature and Inflaton Mass Bounds from Thermalization After Inflation

We consider the conditions for the decay products of perturbative inflaton decay to thermalize. The importance of considering the full spectrum of inflaton decay products in the thermalization process is emphasized. It is shown that the delay between the end of inflaton decay and thermalization allows the thermal gravitino upper bound on the reheating temperature to be raised from 10^{8} GeV to as much as 10^{12} GeV in realistic inflation models. Requiring that thermalization occurs before nucleosynthesis imposes an upper bound on the inflaton mass as a function of the reheating temperature, m_{S} < 10^{10} (T_{R}/1 GeV)^{7/9} GeV. It is also shown that even in realistic inflation models with relatively large reheating temperatures, it is non-trivial to have thermalization before the electroweak phase transition temperature. Therefore the thermal history of the Universe is very sensitive to details of the inflation model.Comment: 12 Pages LaTeX. Catalysed thermalization discussion correcte

Considerations in the determination of orientational order parameters from X-ray scattering experiments

An assessment of the data processing and analysis methods used to obtain the second- and fourth-rank orientational order parameters of liquid crystals from X-ray scattering experiments has been carried out, using experimental data from four extensively studied alkyl-cyanobiphenyls and calculated data generated from two general types of theoretical orientational distribution function. The application of a background subtraction and two different baseline correction methods to the scattering profiles is assessed, along with three different methods to analyse the processed data. The choice of baseline correction method is shown to have a significant effect: an offset to zero overestimates the order parameters from the experimental and calculated data sets, particularly for lower order parameters arising from broad distributions, whereas an offset to a value estimated from regions of low scattering intensity provides experimental values close to those reported from other experimental techniques. By contrast, the three different analysis methods are shown generally to result in relatively small absolute differences between the order parameters. We outline a straightforward general approach to experimental X-ray scattering data processing and analysis for uniaxial phases that results in order parameters that match well with those reported using other experimental techniques

The Ursinus Weekly, February 15, 1973

Girls win first meet in new Elliott Pool • 1973 Arts Festival has much to offer • Student Union to open Monday, February 19 • Editorial: Monday to Thursday • First Semester Dean\u27s List • Film review: The Philosopher king • Meistersingers plan busy Spring series • Mermaids sink Temple • U.C. hosts soccer tourney • Win some; Lose one • Bears un-hooped • Forfeits costly; Bear matmen splithttps://digitalcommons.ursinus.edu/weekly/1096/thumbnail.jp

The Ursinus Weekly, December 7, 1972

Ursinus Board of Directors meets; Acts on degree policy, appointments • Dr. E. H. Miller elected vice president of Northeast Political Science Association • Eleven U.C. students named to Who\u27s who • Dr. James Craft presents paper to Northeast group • Editorial: A little secret; Start suggesting stories! • Faculty portrait: Peter Forrest Small • The Case of the missing counselor • Student Union group outlines plans for Spring, \u2773 opening • Yearbook staff to present campus life realistically • Letters to the editor • Messiah performance to be thirty fifth at U.C. • Dr. Carl F. Henry, theologian, speaks at college forum • Cagers open with victory; Late rally nips Fords • U.C. hockey players off to California • Sig Rho whips Beta Sig in Ursinus football classichttps://digitalcommons.ursinus.edu/weekly/1093/thumbnail.jp