8 research outputs found

    Properties of the Young Milky Way Globular Cluster Whiting 1 from Near-Infrared Photometry

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    Whiting 1 is a member of the fast-growing group of young globular clusters in the Milky Way halo. Preliminary estimates of its fundamental parameters have been provided using optical photometry and low resolution spectroscopy. In an attempt to strengthen our knowledge of Whiting 1, in this study we employ a complementary approach. Isochrone fitting method was applied on the Near-Infrared Color-Magnitude Diagram and yields an age t=5.7±\pm0.3 Gyr, metallicity zz=0.006±\pm0.001 ([Fe/H]=−-0.5±\pm0.1) and distance modulus (m−M)0(m-M)_0=17.48±\pm0.10. Our results confirm that Whiting 1 is a young and moderately metal-rich globular cluster. It is one of the youngest from the Sgr dSph. We fitted an Elson, Fall and Freeman (EFF) profile to the near-infrared number counts, and measured cluster core radius rcr_c=9.1′′{\prime\prime}±\pm3.9′′{\prime\prime}. Two probable eclipsing variables in the cluster were found from multi-epoch VV band photometry. Finally, an unknown galaxy cluster was identified on our KK vs. (J−K)(J-K) color-magnitude diagram. It has a redshift z∼\sim1, and it is located at about 1′{\prime} from the center of Whiting 1 at αJ2000=02h02m56.6s\alpha_{J2000}=02^{h} 02^{m} 56.6^{s}, δJ2000=−03∘16′09′′\delta_{J2000}=-03^{\circ} 16{\prime} 09{\prime\prime}, contaminating the cluster photometry.Comment: Accepted for publication in MNRAS, 6 pages, 8 figure

    Intranight variability of 3C 454.3 during its 2010 November outburst

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    Context. 3C 454.3 is a very active flat spectrum radio quasar (blazar) that has undergone a recent outburst in all observed bands, including the optical. Aims. In this work we explore the short-term optical variability of 3C 454.3 during its outburst by searching for time delays between different optical bands. Finding one would be important for understanding the evolution of the spectrum of the relativistic electrons, which generate the synchrotron jet emission. Methods. We performed photometric monitoring of the object by repeating exposures in different optical bands (BVRI). Occasionally, different telescopes were used to monitor the object in the same band to verify the reliability of the smallest variations we observed. Results. Except on one occasion, where we found indications of a lag of the blue wavelengths behind the red ones, the results are inconclusive for most of the other cases. There were either no structures in the light curves to be able to search for patterns, or else different approaches led to different conclusions.Comment: 4 pages, 4 figures. Accepted for publication in A&

    Trauma informed interventions to reduce seclusion, restraint and restrictive practices amongst staff caring for children and adolescents with challenging behaviours : a systematic review

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    Engaging with children and adolescents in mental health settings who are exhibiting behaviours that challenge can often result in the use of seclusion, restraint and coercive practices. It is recognised that more therapeutic ways to engage this population are needed, adopting trauma informed interventions may provide a solution. The aim of this systematic review is to synthesize the evidence in relation to the effect of trauma-informed interventions on coercive practices in child and adolescent residential settings. The review is guided by elements of the Cochrane Handbook for Systematic Reviews of Interventions and reported using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) checklist. Results were synthesized and reported narratively. Nine studies met the eligibility criteria for this review. There was a lack of homogeneity amongst the studies. The trauma-informed interventions used were typically multi-faceted, underpinned by a variety of approaches and sought to bring about changes to clinical practice. Most studies (n = 8) reported significant reductions in the use of restrictive practices following the implementation of a trauma informed approach. The use of a trauma-informed approach, underpinned by an organisational change or implementation strategy, have the potential to reduce coercive practices with children and adolescents. However, the included interventions were insufficiently described to draw strong conclusions.PeerReviewe
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