288 research outputs found

    AgapeZ1: a Large Amplification Microlensing Event or an Odd Variable Star Towards the Inner Bulge of M31

    Full text link
    AgapeZ1 is the brightest and the shortest duration microlensing candidate event found in the Agape data. It occured only 42" from the center of M31. Our photometry shows that the half intensity duration of the event6 is 4.8 days and at maximum brightness we measure a stellar magnitude of R=18.0 with B-R=0.80 mag color. A search on HST archives produced a single resolved star within the projected event position error box. Its magnitude is R=22.Comment: 4 pages with 5 figure

    Direct and indirect relationships between parental personality and externalising behaviour:The role of negative parenting

    Get PDF
    Although the impact of parent characteristics and parenting practices on the development of behavioural problems in childhood is often recognised, only a few research programmes have assessed the unique contributions of negative parenting as well as the parent personality characteristics in the same study. Using the Five Factor Model, we examined the extent to which mothers' and father's personality characteristics were related to parenting and children's externalising behaviour in a proportional stratified sample of 599 nonclinical elementary school-aged children. Path analysis indicated that negative parenting practices and parents personality characteristics operate together to predict children's externalising problem behaviour. Consistent with past research (Patterson & Dishion, 1988; Patterson, Reid, & Dishion, 1992), parent personality traits were indirectly related to children's externalising problem behaviour. Their effect was mediated by negative parenting practices. But in addition and in contrast to Patterson's theoretical model, parent personality traits also contributed directly to children's externalising problem behaviour. For the mother data, as well as for the father data, the personality dimensions Emotional Stability and Conscientiousness were negatively and Autonomy was positively related to children's externalising problem behaviours

    Coherent state formulation of pion radiation from nucleon antinucleon annihilation

    Full text link
    We assume that nucleon antinucleon annihilation is a fast process leading to a classical coherent pion pulse. We develop the quantum description of such pion waves based on the method of coherent states. We study the consequences of such a description for averages of charge types and moments of distributions of pion momenta with iso-spin and four-momentum conservation taken into account. We briefly discuss the applicability of our method to annihilation at rest, where we find agreement with experiment, and suggest other avenues for its use.Comment: 24 pages, 3 figures, 1 table, PSI-preprin

    Spectrum and Variability of Mrk501 as observed by the CAT Imaging Telescope

    Get PDF
    The CAT Imaging Telescope has observed the BL Lac object Markarian 501 between March and August 1997. We report here on the variability over this time including several large flares. We present also preliminary spectra for all these data, for the low emission state, and for the largest flare.Comment: 4 pages, 4 figures, Late

    Detection of Vhe Gamma-Rays from MRK 501 with the Cat Imaging Telescope

    Get PDF
    The CAT imaging telescope on the site on the former solar plant Themis has been observing gamma-rays from Mrk501 above 220 GeV in March and April 1997. This source is shown to be highly variable and the light curve is presented. The detected gamma-ray rate for the most intense flare is in excess of 10 per minute.Comment: 5 pages, 4 figures, Tex, contribution to 25th ICRC Durba

    Observation of the Crab Nebula Gamma-Ray Emission Above 220 Gev by the Cat Cherenkov Imaging Telescope

    Get PDF
    The CAT imaging telescope, recently built on the site of the former solar plant Themis (French Pyrenees), observed gamma-rays from the Crab nebula from October 1996 to March 1997. This steady source, often considered as the standard candle of very-high-energy gamma-ray astronomy, is used as a test-beam to probe the performances of the new telescope, particularly its energy threshold (220 GeV at 20 degrees zenith angle) and the stability of its response. Due to the fine-grain camera, an accurate analysis of the longitudinal profiles of shower images is performed, yielding the source position in two dimensions for each individual shower.Comment: 5 pages, 3 figures, Tex, contribution to 25th ICRC Durba

    AGAPE: a microlensing search in the direction of M31

    Get PDF
    A status report of the microlensing search by the pixel method in the direction of M31, on the 2 meter telescope at Pic du Midi is given. Pixels are stable to a level better than 0.5%. Pixel variations as small as 0.02 magnitude can clearly be detected

    Variable stars towards the bulge of M31: the AGAPE catalogue

    Full text link
    We present the AGAPE astrometric and photometric catalogue of 1579 variable stars in a 14'x10' field centred on M31. This work is the first survey devoted to variable stars in the bulge of M31. The R magnitudes of the objects and the B-R colours suggest that our sample is dominated by red long-period variable stars (LPV), with a possible overlap with Cepheid-like type II stars. Twelve nova candidates are identified. Correlations with other catalogues suggest that 2 novae could be recurrent novae and provide possible optical counterparts for 2 supersoft X-ray sources candidates observed with Chandra.Comment: 11 pages, Latex, accepted for publication in A&
    • …
    corecore