Yazar "Rykoff, E. S." seçeneğine göre listele

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    Öğe
    Exploring broadband GRB behavior during ?-ray emission
    (Iop Publishing Ltd, 2007) Yost, S. A.; Swan, H. F.; Rykoff, E. S.; Aharonian, F.; Akerlof, C. W.; Alday, A.; Ashley, M. C. B.
    The robotic ROTSE-III telescope network detected prompt optical emission contemporaneous with the gamma-ray emission of Swift events GRB 051109A and GRB 051111. Both data sets have continuous coverage at high signal-to-noise levels from the prompt phase onward, and thus the early observations are readily compared to the Swift XRT and BAT high-energy detections. In both cases, the optical afterglow is established, declining steadily during the prompt emission. For GRB 051111, there is evidence of an excess optical component during the prompt emission. The component is consistent with the flux spectrally extrapolated from the gamma-rays, using the gamma-ray spectral index. A compilation of spectral information from previous prompt detections shows that such a component is unusual. The existence of two prompt optical components-one connected to the high-energy emission, the other to separate afterglow flux, as indicated in GRB 051111-is not compatible with a simple external-external'' shock model for the GRB and its afterglow.
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    Öğe
    Prompt optical observations of GRB 080330 and GRB 080413A
    (Amer Inst Physics, 2008) Yuan, F.; Rykoff, E. S.; Schaefer, B. E.; Rujopakarn, W.; Guever, V; Aharonian, F.; Akerlof, C. W.
    We report on the results of rapid responses to GRB 080330 and GRB 080413A by the ROTSE-IIIb and ROTSE-IIIc telecopes. In both cases, optical follow-up started during the prompt emission phase and recorded optical flares peaking at similar times as the last hard X-ray pulses detected by the Swift BAT. For both events, the XRT observations started at the end of the prompt BAT detection and displayed an evolution in time opposite to the optical lightcurve. These very early observations provide us an opportunity to probe the onset of afterglow for these two events.
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    Öğe
    ROITSE-III performance in the swift era
    (Amer Inst Physics, 2006) Yost, S. A.; Rykoff, E. S.; Aharonian, F.; Akerlof, C. W.; Ashley, M. C. B.; Barthelmy, S.; Gehrels, N.
    We report the successful performance of the Robotic Optical Transient Search Experiment (ROTSE) to promptly-disseminated Swift GRB triggers. ROTSE-III is a worldwide network of 4 unfiltered 0.45m optical telescopes. The telescopes operate robotically, automatically responding to GRB position triggers with a preset observations sequence. Including weather and other downtime, ROTSE-III can immediately respond to similar to 40% of Swift trigger positions, with shutter open within approximately 6-8 seconds from the trigger dissemination. We discuss improvements made possible in the automated response the the small, accurate Swift error boxes. We report ROTSE-III's general results, including OTs discovered or confirmed, the distribution of imaging start times relative to the GRB duration, and an overview of OT lightcurves.