The long burst GRB 050717 was observed simultaneously by the Burst Alert Telescope (BAT) on Swift and the Konus instrument on Wind. Significant hard to soft spectral evolution was seen. Early ...gamma-ray and X-ray emission was detected by both BAT and the X-Ray Telescope (XRT) on Swift. The XRT continued to observe the burst for 7.1 days and detect it for 1.4 days. The X-ray light curve showed a classic decay pattern; the afterglow was too faint for a jet break to be detected. No optical, infrared, or ultraviolet counterpart was discovered despite deep searches within 14 hr of the burst. Two particular features of the prompt emission make GRB 050717 a very unusual burst. First, the peak of the uF(u) spectrum was observed to be 2401 super(+781 -568) keV for the main peak, which is the highest value of E sub(peak) ever observed. Second, the spectral lag for GRB 050717 was determined to be 2.5 c 2.6 ms, consistent with zero and unusually short for a long burst. This lag measurement suggests that this burst has a high intrinsic luminosity and hence is at highredshift (z > 2.7). Despite these unusual features, GRB 050717 exhibits the classic prompt and afterglow behavior of a gamma-ray burst.
Gamma-ray bursts (GRBs) come in two classes: long ( > 2 s), soft-spectrum bursts and short, hard events. Most progress has been made on understanding the long GRBs, which are typically observed at ...high redshift (z 1) and found in subluminous star-forming host galaxies. They are likely to be produced in core- collapse explosions of massive stars. In contrast, no short GRB had been accurately ( < 10") and rapidly (minutes) located. Here we report the detection of the X-ray afterglow from: and the localization of: the short burst GRB 050509B. Its position on the sky is near a luminous, non-star-forming elliptical galaxy at a redshift of 0.225, which is the location one would expect if the origin of this GRB is through the merger of neutron-star or black-hole binaries. The X-ray afterglow was weak and faded below the detection limit within a few hours; no optical afterglow was detected to stringent limits, explaining the past difficulty in localizing short GRBs.
The present study evaluated the impact of a structured aftercare programme following residential treatment for severe alcohol and/or heroin dependent clients. Over 17 months, 77 participants were ...recruited to the study and allocated randomly to either a structured aftercare (SA) programme or to unstructured aftercare (UA) of crisis counselling on request. Independent clinicians interviewed participants and collaterals, at 4-month (median) intervals, for 12 months following residential treatment. SA compared to UA was associated with a fourfold increase in aftercare attendance and one-third the rate of uncontrolled principal substance use at follow-up. Participants who attended either type of aftercare relapsed a median of 134 days later than those who attended no aftercare. Overall, 23% of monitored participants remained abstinent throughout, 21% maintained controlled substance use and 56% relapsed, within a median of 36 days following residential treatment. The only significant predictor of days to relapse, controlling for age, was pretreatment use of additional substances. Participants with pretreatment additional substance use relapsed a median of 192 days earlier than those who had used no other substances. The degree of agreement between participant self-reports and collateral reports was fair-to-moderate and moderate among collaterals. Intention-to-treat analyses revealed significant and clinically meaningful reductions in substance use in this sample of severely dependent residential treatment clients. The generalizability of these results is limited because of significant differences in age and presenting substance between the study sample and other clients admitted to the service during the study. This latter group of younger, male, heroin-dependent clients with polydrug use who refuse opioid pharmacotherapy, are more likely to drop out of treatment or relapse early following treatment and continue to present a challenge to treatment services. Sannibale C, Van den Bossche E, O'Connor D, Zador D, Capus C, Gregory K, McKenzie M. Aftercare attendance and post-treatment functioning of severely substance dependent residential treatment clients. Drug Alcohol Rev 2003;22:181 - 190
We report the Swift discovery of nearby long, soft gamma-ray burst GRB 100316D, and the subsequent unveiling of its low redshift host galaxy and associated supernova. We derive the redshift of the ...event to be z = 0.0591 +/- 0.0001 and provide accurate astrometry for the GRB-SN. We study the extremely unusual prompt emission with time-resolved gamma-ray to X-ray spectroscopy, and find that the spectrum is best modelled with a thermal component in addition to a synchrotron emission component with a low peak energy. The X-ray light curve has a remarkably shallow decay out to at least 800 s. The host is a bright, blue galaxy with a highly disturbed morphology and we use Gemini South, VLT and HST observations to measure some of the basic host galaxy properties. We compare and contrast the X-ray emission and host galaxy of GRB 100316D to a subsample of GRB-SNe. GRB 100316D is unlike the majority of GRB-SNe in its X-ray evolution, but resembles rather GRB 060218, and we find that these two events have remarkably similar high energy prompt emission properties. Comparison of the host galaxies of GRB-SNe demonstrates, however, that there is a great diversity in the environments in which GRB-SNe can be found. GRB 100316D is an important addition to the currently sparse sample of spectroscopically confirmed GRB-SNe, from which a better understanding of long GRB progenitors and the GRB--SN connection can be gleaned.
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