73 research outputs found

    Modelling the Molecular Gas in NGC 6240

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    We present the first observations of H13^{13}CN(10)(1-0), H13^{13}CO+(10)^+(1-0) and SiO(21)(2-1) in NGC\,6240, obtained with the IRAM PdBI. Combining a Markov Chain Monte Carlo (MCMC) code with Large Velocity Gradient (LVG) modelling, and with additional data from the literature, we simultaneously fit three gas phases and six molecular species to constrain the physical condition of the molecular gas, including mass-luminosity conversion factors. We find 1010M\sim10^{10}M_\odot of dense molecular gas in cold, dense clouds (Tk10T_{\rm k}\sim10\,K, nH2106n_{{\rm H}_2}\sim10^6\,cm3^{-3}) with a volume filling factor <0.002<0.002, embedded in a shock heated molecular medium (Tk2000T_{\rm k}\sim2000\,K, nH2103.6n_{{\rm H}_2}\sim10^{3.6}\,cm3^{-3}), both surrounded by an extended diffuse phase (Tk200T_{\rm k}\sim200\,K, nH2102.5n_{{\rm H}_2}\sim10^{2.5}\,cm3^{-3}). We derive a global αCO=1.51.17.1\alpha_{\rm CO}=1.5^{7.1}_{1.1} with gas masses log10(M/[M])=10.110.010.8\log_{10}\left(M / [M_\odot]\right)=10.1_{10.0}^{10.8}, dominated by the dense gas. We also find αHCN=321389\alpha_{\rm HCN} = 32^{89}_{13}, which traces the cold, dense gas. The [12^{12}C]/[13^{13}C] ratio is only slightly elevated (986523098^{230}_{65}), contrary to the very high [CO]/[13^{13}CO] ratio (300-500) reported in the literature. However, we find very high [HCN]/[H13^{13}CN] and [HCO+^+]/[H13^{13}CO+^+] abundance ratios (300200500)(300^{500}_{200}) which we attribute to isotope fractionation in the cold, dense clouds.Comment: 27 pages, 17 figures, 9 tables. Accepted in Ap

    Chemically Distinct Nuclei and Outflowing Shocked Molecular Gas in Arp 220

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    We present the results of interferometric spectral line observations of Arp 220 at 3.5mm and 1.2mm from the Plateau de Bure Interferometer (PdBI), imaging the two nuclear disks in H13^{13}CN(10)(1 - 0) and (32)(3 - 2), H13^{13}CO+(10)^+(1 - 0) and (32)(3 - 2), and HN13^{13}C(32)(3 - 2) as well as SiO(21)(2 - 1) and (65)(6 - 5), HC15^{15}N(32)(3 - 2), and SO(6655)(6_6 - 5_5). The gas traced by SiO(65)(6 - 5) has a complex and extended kinematic signature including a prominent P Cygni profile, almost identical to previous observations of HCO+(32)^+(3 - 2). Spatial offsets 0.10.1'' north and south of the continuum centre in the emission and absorption of the SiO(65)(6 - 5) P Cygni profile in the western nucleus (WN) imply a bipolar outflow, delineating the northern and southern edges of its disk and suggesting a disk radius of 40\sim40 pc, consistent with that found by ALMA observations of Arp 220. We address the blending of SiO(65)(6 - 5) and H13^{13}CO+(32)^+(3 - 2) by considering two limiting cases with regards to the H13^{13}CO+^+ emission throughout our analysis. Large velocity gradient (LVG) modelling is used to constrain the physical conditions of the gas and to infer abundance ratios in the two nuclei. Our most conservative lower limit on the [H13^{13}CN]/[H13^{13}CO+^+] abundance ratio is 11 in the WN, cf. 0.10 in the eastern nucleus (EN). Comparing these ratios to the literature we argue on chemical grounds for an energetically significant AGN in the WN driving either X-ray or shock chemistry, and a dominant starburst in the EN.Comment: 28 pages, 17 figures, accepted to Ap

    Has education lost sight of children?

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    The reflections presented in this chapter are informed by clinical and personal experiences of school education in the UK. There are many challenges for children and young people in the modern education system and for the professionals who support them. In the UK, there are significant gaps between the highly selective education provided to those who pay privately for it and to the majority of those educated in the state-funded system. Though literacy rates have improved around the world, many children, particularly boys, do not finish their education for reasons such as boredom, behavioural difficulties or because education does not ‘pay’. Violence, bullying, and sexual harassment are issues faced by many children in schools and there are disturbing trends of excluding children who present with behavioural problems at school whose origins are not explored. Excluded children are then educated with other children who may also have multiple problems which often just make the situation worse. The experience of clinicians suggests that school-related mental health problems are increasing in severity. Are mental health services dealing with the consequences of an education system that is not meeting children’s needs? An education system that is testing- and performance-based may not be serving many children well if it is driving important decisions about them at increasingly younger ages. Labelling of children and setting them on educational career paths can occur well before they reach secondary schools, limiting potential very early on in their developmental trajectory. Furthermore, the emphasis at school on testing may come at the expense of creativity and other forms of intelligence, which are also valuable and important. Meanwhile the employment marketplace requires people with widely different skills, with an emphasis on innovation, creativity, and problem solving. Is education losing sight of the children it is educating

    Improving implementation of evidence based practice for people with psychosis through training the wider workforce: Results of the GOALS feasibility randomised controlled trial

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    BACKGROUND AND OBJECTIVES: There is a pressing need to improve access to evidence-based practice for people with psychosis. The primary aim of this study was to assess clinical feasibility of a manualised, evidence-based CBT intervention (GOALS) targeting a personalised recovery goal, delivered by the frontline workforce, following brief training. Secondly, we aimed to conduct preliminary statistical analyses of key outcomes and costs. METHODS:\ud The GOALS study is a feasibility randomised controlled trial (ISRCTN 73188383). 75 participants with current psychosis were recruited and randomly allocated to receive either treatment as usual alone or with GOALS therapy. RESULTS: Brief training enabled frontline staff to deliver the therapy according to protocol and 74% of therapy participants partially or fully achieved their goals. There were significant improvements with a moderate effect size of 0.56 on goal attainment. However, preliminary statistical analyses found no significant differences between groups on our primary outcome of activity levels or other secondary outcomes Health economic analysis found that point estimates of costs, controlling for baseline costs, implied savings (even including intervention costs), but the difference was not statistically significant. LIMITATIONS: The study was designed as a feasibility RCT, and therefore the results of secondary estimates of efficacy effects should be treated with caution. CONCLUSIONS: This approach holds promise in supporting people with psychosis to reach personal recovery goals, cost effectively

    Might Depression, Psychosocial Adversity, and Limited Social Assets Explain Vulnerability to and Resistance against Violent Radicalisation?

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    BACKGROUND: This study tests whether depression, psychosocial adversity, and limited social assets offer protection or suggest vulnerability to the process of radicalisation. METHODS: A population sample of 608 men and women of Pakistani or Bangladeshi origin, of Muslim heritage, and aged 18-45 were recruited by quota sampling. Radicalisation was measured by 16 questions asking about sympathies for violent protest and terrorism. Cluster analysis of the 16 items generated three groups: most sympathetic (or most vulnerable), most condemning (most resistant), and a large intermediary group that acted as a reference group. Associations were calculated with depression (PHQ9), anxiety (GAD7), poor health, and psychosocial adversity (adverse life events, perceived discrimination, unemployment). We also investigated protective factors such as the number social contacts, social capital (trust, satisfaction, feeling safe), political engagement and religiosity. RESULTS: Those showing the most sympathy for violent protest and terrorism were more likely to report depression (PHQ9 score of 5 or more; RR = 5.43, 1.35 to 21.84) and to report religion to be important (less often said religion was fairly rather than very important; RR = 0.08, 0.01 to 0.48). Resistance to radicalisation measured by condemnation of violent protest and terrorism was associated with larger number of social contacts (per contact: RR = 1.52, 1.26 to 1.83), less social capital (RR = 0.63, 0.50 to 0.80), unavailability for work due to housekeeping or disability (RR = 8.81, 1.06 to 37.46), and not being born in the UK (RR = 0.22, 0.08 to 0.65). CONCLUSIONS: Vulnerability to radicalisation is characterised by depression but resistance to radicalisation shows a different profile of health and psychosocial variables. The paradoxical role of social capital warrants further investigation

    High Dense Gas Fraction in Intensely Star-forming Dusty Galaxies

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    We present ALMA and VLA detections of the dense molecular gas tracers HCN, HCO+^+ and HNC in two lensed, high-redshift starbursts selected from the {\it Herschel}-ATLAS survey: {\it H}-ATLAS\,J090740.0-004200 (SDP.9, z1.6z \sim 1.6) and {\it H}-ATLAS\,J091043.1-000321 (SDP.11, z1.8z \sim 1.8). ALMA observed the J=32J = 3-2 transitions in both sources, while the VLA observed the J=10J = 1-0 transitions in SDP.9. We have detected all observed HCN and HCO+^+ lines in SDP.9 and SDP.11, and also HNC(3--2) in SDP.9. The amplification factors for both galaxies have been determined from sub-arcsec resolution CO and dust emission observations carried out with NOEMA and the SMA. The HNC(1--0)/HCN(1--0) line ratio in SDP.9 suggests the presence of photon-dominated regions, as it happens to most local (U)LIRGs. The CO, HCN and HCO+^+ SLEDs of SDP.9 are compatible to those found for many local, infrared (IR) bright galaxies, indicating that the molecular gas in local and high-redshift dusty starbursts can have similar excitation conditions. We obtain that the correlation between total IR (LIRL_{\rm IR}) and dense line (LdenseL_{\rm dense}) luminosity in SDP.9 and SDP.11 and local star-forming galaxies can be represented by a single relation. The scatter of the LIRLdenseL_{\rm IR} - L_{\rm dense} correlation, together with the lack of sensitive dense molecular gas tracer observations for a homogeneous sample of high-redshift galaxies, prevents us from distinguishing differential trends with redshift. Our results suggest that the intense star formation found in some high-redshift dusty, luminous starbursts is associated with more massive dense molecular gas reservoirs and higher dense molecular gas fractions.Comment: Submitted to ApJ. Comments most welcom
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