Context. The molecular gas in the DR21 massive star formation region is known to be affected by the strong UV field from the central star cluster and by a fast outflow creating a bright shock. The ...relative contribution of both heating mechanisms is the matter of a long debate. Aims. By better sampling the excitation ladder of various tracers we provide a quantitative distinction between the different heating mechanisms. Methods. HIFI observations of mid-J transitions of CO and HCO+ isotopes allow us to bridge the gap in excitation energies between observations from the ground, characterizing the cooler gas, and existing ISO LWS spectra, constraining the properties of the hot gas. Comparing the detailed line profiles allows to identify the physical structure of the different components. Results. In spite of the known shock-excitation of H2 and the clearly visible strong outflow, we find that the emission of all lines up to $\ga$2 THz can be explained by purely radiative heating of the material. However, the new Herschel/HIFI observations reveal two types of excitation conditions. We find hot and dense clumps close to the central cluster, probably dynamically affected by the outflow, and a more widespread distribution of cooler, but nevertheless dense, molecular clumps.
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The ISO and IUE spectra of the elliptical nebulae NGC 2022, NGC 6818 and IC 4191 are presented. These spectra are combined with the spectra in the visual wavelength region to obtain a complete, ...extinction corrected, spectrum. The chemical composition of the nebulae is then calculated and compared to previous determinations. A discussion is also given of the exciting stars of the nebulae, and possible evolutionary effects.
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We present the infrared spectrum of the planetary nebula NGC 7027 observed with the Short Wavelength Spectrometer (SWS), on board the Infrared Space Observatory (ISO). These data allow us to derive ...the electron density and, together with the IUE and optical spectra, the electron temperature for several ions. The nebular composition has been determined, the evolutionary status of the central star is discussed and the element depletion in the nebula is given. We conclude that the progenitor was a C-rich star with a mass between 3 and 4 $M_{\odot}$.
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“Water In Star-forming regions with Herschel” (WISH) is a key programme dedicated to studying the role of water and related species during the star-formation process and constraining the physical and ...chemical properties of young stellar objects. The Heterodyne Instrument for the Far-Infrared (HIFI) on the Herschel Space Observatory observed three deeply embedded protostars in the low-mass star-forming region NGC 1333 in several H_216O, H_218O, and CO transitions. Line profiles are resolved for five H_216O transitions in each source, revealing them to be surprisingly complex. The line profiles are decomposed into broad (>20 km s-1), medium-broad (~5-10 km s-1), and narrow (<5 km s-1) components. The H_218O emission is only detected in broad 110-101 lines (>20 km s-1), indicating that its physical origin is the same as for the broad H_216O component. In one of the sources, IRAS4A, an inverse P Cygni profile is observed, a clear sign of infall in the envelope. From the line profiles alone, it is clear that the bulk of emission arises from shocks, both on small (⪉1000 AU) and large scales along the outflow cavity walls (~10 000 AU). The H2O line profiles are compared to CO line profiles to constrain the H2O abundance as a function of velocity within these shocked regions. The H2O/CO abundance ratios are measured to be in the range of ~0.1-1, corresponding to H2O abundances of ~10-5-10-4 with respect to H2. Approximately 5-10% of the gas is hot enough for all oxygen to be driven into water in warm post-shock gas, mostly at high velocities. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Tables 2 and 3 (page 6) are only available in electronic form at http://www.aanda.org
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Forensic psychiatry aims to reduce recidivism and makes use of risk assessment tools to achieve this goal. Various studies have reported on the predictive qualities of these instruments, but it ...remains unclear whether their use is associated with actual prevention of recidivism in clinical care.
To test whether an intervention combining risk assessment and shared care planning is associated with a reduction in violent and criminal behaviour.
A cluster randomised controlled trial (Netherlands Trial Register number NTR1042) was conducted in three out-patient forensic psychiatric clinics. The intervention comprised risk assessment with the Short Term Assessment of Risk and Treatability (START) and a shared care planning protocol formulated according to shared decision-making principles. The control group received usual care. The outcome consisted of the proportion of clients with violent or criminal incidents at follow-up.
In total 58 case managers and 632 of their clients were included. In the intervention group (n = 310), 65% received the intervention at least once. Findings showed a general treatment effect (22% of clients with an incident at baseline v. 15% at follow-up, P<0.01) but no significant difference between the two treatment conditions (odds ratio (OR) = 1.46, 95% CI 0.89-2.44, P = 0.15).
Although risk assessment is common practice in forensic psychiatry, our results indicate that the primary goal of preventing recidivism was not reached through risk assessment embedded in shared decision-making.
The complete ISO spectrum of NGC 6302 Molster, F. J.; Lim, T. L.; Sylvester, R. J. ...
Astronomy & astrophysics,
06/2001, Volume:
372, Issue:
1
Journal Article
Peer reviewed
Open access
We present the combined Infrared Space Observatory Short-Wavelength Spectrometer and Long-Wavelength Spectrometer 2.4-197 μm spectrum of the Planetary Nebula NGC 6302 which contains in addition to ...strong atomic lines, a series of emission features due to solid state components. The broad wavelength coverage enables us to more accurately identify and determine the properties of both oxygen- and carbon-rich circumstellar dust. A simple model fit was made to determine the abundance and typical temperature of the amorphous silicates, enstatite and forsterite. Forsterite and enstatite do have roughly the same abundance and temperature. The origin and location of the dust in a toroidal disk around the central star are discussed.
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The ISO and IUE spectra of the elliptical nebulae NGC 7662 and NGC 6741 are presented. These spectra are combined with the spectra in the visual wavelength region to obtain a complete, extinction ...corrected, spectrum. The chemical composition of the nebulae is then calculated and compared to previous determinations. The abundances found are compared to determinations made in other nebulae using ISO data. A discussion is given to see if possible evolutionary effects can be found from the abundance differences.
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Abundances of Planetary Nebula NGC 5315 Pottasch, S. R.; Beintema, D. A.; Bernard Salas, J. ...
Astronomy and astrophysics (Berlin),
10/2002, Volume:
393, Issue:
1
Journal Article
Peer reviewed
Open access
The ISO and IUE spectra of the elliptical nebula NGC 5315 is presented. These spectra are combined with the spectra in the visual wavelength region to obtain a complete, extinction corrected, ...spectrum. The chemical composition of the nebulae is then calculated and compared to previous determinations. The HST NICMOS observations of the nebula in 3 emission lines are also presented. These observations are used to determine the helium abundance as a function of position in the nebula. A discussion is given of possible evolutionary effects.
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