Search for R-parity Violating Decays of Supersymmetric Particles at LEP

Searches for pair-produced charginos, neutralinos and scalar fermions decaying via R-parity violating / /\' and /\'' couplings with the OPAL detector at LEP are presented at sqrt(s)=189 GeV. Partial updates using data up to the highest energies of LEP, sqrt(s)=209 GeV, are also given.Comment: 5 pages, 11 figures. To be published in the Proceedings of DPF2000, The Meeting of The Division of Particles and Fields of The American Physical Society, Columbus, Ohio, 9-12 August 2000, (Supplement of the International Journal of Modern Physics A (IJMP)

Low x particle spectra in the Modified Leading Logarithm Approximation

We show that the higher moments of the evolution obtained from the Modified Leading Logarithm Approximation may be regarded as spurious higher order terms in perturbation theory, and that neglecting them leads to a good description of the data around and above the peak in $\xi=\ln (1/x)$. Furthermore, we use this study of the moments to show that at high energy the Limiting Spectrum with Local Parton-Hadron Duality may also be derived from the Modified Leading Logarithm Approximation without any non-perturbative assumptions.Comment: Submitted to Eur. Phys. J.,

[Review of] Shay Youngblood. The Big Mama Stories

Shay Youngblood learns how to tell stories from her many Big Mamas. The tales answer questions about her biological mother who is dead, what it means to be a woman, and how it feels to be black in Princeton, Georgia, prior to the civil rights movement. The voices of Big Mama, Miss Emma Lou, Aunt Mae and others leap off the page, and take readers on a journey into homes, on porches, and down the river fishing. Each story is a piece of a puzzle that adds to form a complete picture of the protagonist

[Review of] Margaret B. Wilkerson, ed. 9 Plays by Black Women

Black women writers, primarily novelists, have taken center stage for the last two decades, but black women playwrights have not been given similar coverage. The explanation, in part, is that plays are often only published after successful productions, and the plays by the majority of black women have only been produced in local, small theaters. Consequently, their works have not been given serious critical attention. Margaret Wilkerson\u27s 9 Plays by Black Women showcases plays by established and well celebrated black female playwrights, like Alice Childress, Lorraine Hansberry, Ntozake Shange, and Beah Richards as well as less well-known playwrights whose works deserve to be produced more widely such as P. J. Gibson, Kathleen Collins, Aishah Rahman and Alexis De Veaux

Design and calibration of far-UV photometers for rocket use

Design and calibration of far UV photometer

Analog-to-digital conversion techniques for precision photometry

Three types of analog-to-digital converters are described: parallel, successive-approximation, and integrating. The functioning of comparators and sample-and-hold amplifiers is explained. Differential and integral linearity are defined, and good and bad examples are illustrated. The applicability and relative advantages of the three types of converters for precision astronomical photometric measurements are discussed. For most measurements, integral linearity is more important than differential linearity. Successive-approximation converters should be used with multielement solid state detectors because of their high speed, but dual slope integrating converters may be superior for use with single element solid state detectors where speed of digitization is not a factor. In all cases, the input signal should be tailored so that they occupy the upper part of the converter's dynamic range; this can be achieved by providing adjustable gain, or better by varying the integration time of the observation if possible