The optical polarization of Epsilon Aurigae through the 1982-84 eclipse

About 350 nights observations on the 61-cm telescope at Pine Mt. Observatory were made of the variable polarization of Eps. Aurigae during 1982-85, in the U, B, and V color bands. The V data are the most complete and are shown. In terms of the overall features the curves in all three colors are quite similar. The typical errors per nightly point in the V curves are about 0.015% for either of the two normalized, equatorial Stokes parameters Q and U. Note that there is a large background or constant component of some 2.5%, position angle around 135 deg. This is presumably largely interstellar, and the intrinsic polarization probably does not much exceed the amplitude of the variable component, approx. 0.5%. A few field-star polarizations were measured but a very clear pattern was not obtained in this part of the sky

Continuous-wave Raman laser pumped within a semiconductor disk laser cavity

A KGd(WO4)(2) Raman laser was pumped within the cavity of a cw diode-pumped InGaAs semiconductor disk laser (SDL). The Raman laser threshold was reached for 5: 6W of absorbed diode pump power, and output power up to 0.8W at 1143nm, with optical conversion efficiency of 7.5% with respect to the absorbed diode pump power, was demonstrated. Tuning the SDL resulted in tuning of the Raman laser output between 1133 and 1157nm

Physics Analysis Expert PAX: First Applications

PAX (Physics Analysis Expert) is a novel, C++ based toolkit designed to assist teams in particle physics data analysis issues. The core of PAX are event interpretation containers, holding relevant information about and possible interpretations of a physics event. Providing this new level of abstraction beyond the results of the detector reconstruction programs, PAX facilitates the buildup and use of modern analysis factories. Class structure and user command syntax of PAX are set up to support expert teams as well as newcomers in preparing for the challenges expected to arise in the data analysis at future hadron colliders.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 7 pages, LaTeX, 10 eps figures. PSN THLT00

X-ray total mass estimate for the nearby relaxed cluster A3571

We constrain the total mass distribution in the cluster A3571, combining spatially resolved ASCA temperature data with ROSAT imaging data with the assumption that the cluster is in hydrostatic equilibrium. The total mass within r_500 (1.7/h_50 Mpc) is M_500 = 7.8[+1.4,-2.2] 10^14/ h_50 Msun at 90% confidence, 1.1 times smaller than the isothermal estimate. The Navarro, Frenk & White ``universal profile'' is a good description of the dark matter density distribution in A3571. The gas density profile is shallower than the dark matter profile, scaling as r^{-2.1} at large radii, leading to a monotonically increasing gas mass fraction with radius. Within r_500 the gas mass fraction reaches a value of f_gas = 0.19[+0.06,-0.03] h_50^{-3/2} (90% confidence errors). Assuming that this value of f_gas is a lower limit for the the universal value of the baryon fraction, we estimate the 90% confidence upper limit of the cosmological matter density to be Omega_m < 0.4.Comment: 10 pages, 4 figures, accepted by Ap

How much dark matter is there inside early-type galaxies?

We study the luminous mass as a function of the dynamical mass inside the effective radius (r_e) of early-type galaxies (ETGs) to search for differences between these masses. We assume Newtonian dynamics and that any difference between these masses is due to the presence of dark matter. We use several samples of ETGs -ranging from 19 000 to 98 000 objects- from the ninth data release of the Sloan Digital Sky Survey. We perform Monte Carlo (MC) simulations of galaxy samples and compare them with real samples. The main results are: i) MC simulations show that the distribution of the dynamical vs. luminous mass depends on the mass range where the ETGs are distributed (geometric effect). This dependence is caused by selection effects and intrinsic properties of the ETGs. ii) The amount of dark matter inside r_e is approximately 7% +- 22%. iii) This amount of dark matter is lower than the minimum estimate (10%) found in the literature and four times lower than the average (30%) of literature estimates. However, if we consider the associated error, our estimate is of the order of the literature average.Comment: 24 pages, 12 figures. MNRAS accepte

Perceived importance of components of asynchronous music in circuit training

This study examined regular exercisers’ perceptions of specific components of music during circuit training. Twenty-four men (38.8 years, s = 11.8 years) and 31 women (32.4 years, s = 9.6 years) completed two questionnaires immediately after a circuit training class. Participants rated the importance of 13 components of music (rhythm, melody, etc.) in relation to exercise enjoyment, and each completed the Affect Intensity Measure (Larsen, 1984) to measure emotional reactivity. Independent t tests were used to evaluate gender differences in perceptions of musical importance. Pearson correlations were computed to evaluate the relationships between affect intensity, age and importance of musical components. Consistent with previous research and theoretical predictions, rhythm response components (rhythm, tempo, beat) were rated as most important. Women rated the importance of melody significantly higher than did men, while men gave more importance to music associated with sport. Affect intensity was found to be positively and significantly related to the perceived importance of melody, lyrical content, musical style, personal associations and emotional content. Results suggest that exercise leaders need to be sensitive to personal factors when choosing music to accompany exercise. Qualitative research that focuses on the personal meaning of music is encouraged

A comparison of four different imaging modalities - conventional, cross polarized, infra-red and ultra-violet in the assessment of childhood bruising

Background It is standard practice to image concerning bruises in children. We aim to compare the clarity and measurements of bruises using cross polarized, infra-red (IR) and ultra-violet (UV) images to conventional images. Methods Children aged <11 years with incidental bruising were recruited. Demographics, skin and bruise details were recorded. Bruises were imaged by standard protocols in conventional, cross-polarized, IR and UV lights. Bruises were assessed in vivo for contrast, uniformity and diffuseness, and these characteristics were then compared across image modalities. Color images (conventional, cross polarized) were segmented and measured by ImageJ. Bruises of grey scale images (IR, UV) were measured by a ‘plug in’ of ImageJ. The maximum and minimum Feret's diameter, area and aspect ratio, were determined. Comparison of measurements across imaging modalities was conducted using Wilcoxon rank sum tests and modified Bland-Altman graphs. Significance was set at p < 0.05. Results Twenty five children had 39 bruises. Bruises that were of low contrast, i.e. difficult to distinguish from surrounding skin, were also more diffuse, and less uniformity in vivo. Low contrast bruises were best seen on conventional and cross-polarized images and less distinctive on IR and UV images. Of the 19 bruises visible in all modalities, the only significant difference was maximum and minimum Feret's diameters and area were smaller on IR compared to conventional images. Aspect ratios were not affected by the modality. Conclusions Conventional and cross-polarized imaging provides the most consistent bruise measurement, particularly in bruises that are not easily distinguished from surrounding skin visually