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Context. Sh2-104 is a Galactic H ii region with a bubble morphology, detected at optical and radio wavelengths. It is considered the first observational confirmation of the collect-and-collapse model of triggered star-formation.\ud \ud Aims. We aim to analyze the dust and gas properties of the Sh2-104 region to better constrain its effect on local future generations of stars. In addition, we investigate the relationship between the dust emissivity index β and the dust temperature, Tdust.\ud \ud Methods. Using Herschel PACS and SPIRE images at 100, 160, 250, 350 and 500 μm we determine Tdust and β throughout Sh2-104, fitting the spectral energy distributions (SEDs) obtained from aperture photometry. With the SPIRE Fourier-transform spectrometer (FTS) we obtained spectra at different positions in the Sh2-104 region. We detect J-ladders of 12CO and 13CO, with which we derive the gas temperature and column density. We also detect proxies of ionizing flux as the [Nii] 3P1-3P0 and [Ci] 3P2–3P1 transitions.\ud \ud Results. We find an average value of β ~ 1.5 throughout Sh2-104, as well as a Tdust difference between the photodissociation region (PDR, ~25 K) and the interior (~40 K) of the bubble. We recover the anti-correlation between β and dust temperature reported numerous times in the literature. The relative isotopologue abundances of CO appear to be enhanced above the standard ISM values, but the obtained value is very preliminary and is still affected by large uncertainties.

SPIRE, the Spectral and Photometric Imaging REceiver, is the Herschel Space Observatory's submillimetre camera and spectrometer. It contains a three-band imaging photometer operating at 250, 350 and 500 μm, and an imaging Fourier-transform spectrometer (FTS) covering 194–671 μm (447-1550 GHz). In this paper we describe the initial approach taken to the absolute calibration of the SPIRE instrument using a combination of the emission from the Herschel telescope itself and the modelled continuum emission from solar system objects and other astronomical targets. We present the photometric, spectroscopic and spatial accuracy that is obtainable in data processed through the “standard” pipelines. The overall photometric accuracy at this stage of the mission is estimated as 15% for the photometer and between 15 and 50% for the spectrometer. However, there remain issues with the photometric accuracy of the spectra of low flux sources in the longest wavelength part of the SPIRE spectrometer band. The spectrometer wavelength accuracy is determined to be better than 1/10th of the line FWHM. The astrometric accuracy in SPIRE maps is found to be 2 arcsec when the latest calibration data are used. The photometric calibration of the SPIRE instrument is currently determined by a combination of uncertainties in the model spectra of the astronomical standards and the data processing methods employed for map and spectrum calibration. Improvements in processing techniques and a better understanding of the instrument performance will lead to the final calibration accuracy of SPIRE being determined only by uncertainties in the models of astronomical standards.

We obtained Herschel PACS and SPIRE images of the thermal emission of the debris disk around the A5V star �� Pic. The disk is well resolved in the PACS filters at 70, 100, and 160 ��m. The surface brightness profiles between 70 and 160 ��m show no significant asymmetries along the disk, and are compatible with 90% of the emission between 70 and 160 ��m originating in a region closer than 200 AU to the star. Although only marginally resolving the debris disk, the maps obtained in the SPIRE 250 - 500 ��m filters provide full-disk photometry, completing the SED over a few octaves in wavelength that had been previously inaccessible. The small far-infrared spectral index (�� = 0.34) indicates that the grain size distribution in the inner disk (, Accepted for publication in Astronomy&Astrophysics, Herschel First Results special issue

Context. RCW 120 is a well-studied, nearby Galactic H ii region with ongoing star formation in its surroundings. Previous work has shown that it displays a bubble morphology at mid-infrared wavelengths, and has a massive layer of collected neutral material seen at sub-mm wavelengths. Given the well-defined photo-dissociation region (PDR) boundary and collected layer, it is an excellent laboratory to study the “collect and collapse” process of triggered star formation. Using Herschel Space Observatory data at 100, 160, 250, 350, and 500 μm, in combination with Spitzer and APEX-LABOCA data, we can for the first time map the entire spectral energy distribution of an H ii region at high angular resolution.\ud \ud Aims. We seek a better understanding of RCW 120 and its local environment by analysing its dust temperature distribution. Additionally, we wish to understand how the dust emissivity index, β, is related to the dust temperature.\ud \ud Methods. We determine dust temperatures in selected regions of the RCW 120 field by fitting their spectral energy distribution (SED), derived using aperture photometry. Additionally, we fit the SED extracted from a grid of positions to create a temperature map.\ud \ud Results. We find a gradient in dust temperature, ranging from 30 K in the interior of RCW 120, to ~20 K for the material collected in the PDR, to ~10 K toward local infrared dark clouds and cold filaments. There is an additional, hotter (~100 K) component to the dust emission that we do not investigate here. Our results suggest that RCW 120 is in the process of destroying the PDR delineating its bubble morphology. The leaked radiation from its interior may influence the creation of the next generation of stars. We find support for an anti-correlation between the fitted temperature and β, in rough agreement with what has been found previously. The extended wavelength coverage of the Herschel data greatly increases the reliability of this result.

We obtained Herschel PACS and SPIRE images of the thermal emission of the debris disk around the A5V star β Pic. The disk is well resolved in the PACS filters at 70, 100, and 160 μm. The surface brightness profiles between 70 and 160 μm show no significant asymmetries along the disk, and are compatible with 90% of the emission between 70 and 160 μm originating in a region closer than 200 AU to the star. Although only marginally resolving the debris disk, the maps obtained in the SPIRE 250–500 μm filters provide full-disk photometry, completing the SED over a few octaves in wavelength that had been previously inaccessible. The small far-infrared spectral index (β = 0.34) indicates that the grain size distribution in the inner disk (

International audience

International audience; The SPIRE instrument on board the Herschel satellite contains an imaging Fourier Transform Spectrometer. This instrument simultaneously covers the 194―672 μm wavelength range, with an unvignetted field of view of 2.6', and pixel FWHM of \tilde16'' (short wavelengths) and \tilde35'' (long wavelengths). It will be possible to operate in a raster mode, and so cover large areas of sky. The data produced will be either low spectral resolution continuum measurements or have higher spectral resolution to observe lines. We describe the instrument characteristics and the software requirements for scientific analysis of the resulting 3D spectral data cubes.

Most building energy simulation programs do not take into account the effect of skylights on energy performance. This paper presents a numerical study on natural laminar convection within vertically eccentric domed cavities heated from the exterior surface. A commercial computational fluid dynamics package employing the control volume approach was used to solve the laminar convective heat transfer within the cavity. This research will lead to the simulation of the energy effects of skylights., 10th IBPSA Building Simulation Conference: 3 September 2007, Beijin, China

Results obtained with preschool children (Homo sapiens) were compared with results previously obtained from capuchin monkeys (Cebus apella) in matching-to-sample tasks featuring hierarchical visual stimuli. In Experiment 1, monkeys, in contrast with children, showed an advantage in matching the stimuli on the basis of their local features. These results were replicated in a 2nd experiment in which control trials enabled the authors to rule out that children used spurious cues to solve the matching task. In a 3rd experiment featuring conditions in which the density of the stimuli was manipulated, monkeys' accuracy in the processing of the global shape of the stimuli was negatively affected by the separation of the local elements, whereas children's performance was robust across testing conditions. Children's response latencies revealed a global precedence in the 2nd and 3rd experiments. These results show differences in the processing of hierarchical stimuli by humans and monkeys that emerge early during childhood.

The spectrum of Saturn has been recorded between 4.5 and 16.0 mu m with the grating mode of the Short-Wavelength Spectrometer (SWS) of ISO. The resolving power is 1500. The main results of this observation are (1) the detection of CO2 CH3C2H and C4H2 in the stratosphere and (2) the detection of H2O in the troposphere. In the 4.5-5.5 mu m range, information is retrieved on the tropospheric composition (NH3, PH3, AsH3, GeH4, CH3D and H2O) down to pressure levels of several bars. Above 7 mu m, the Saturn spectrum probes the upper troposphere and the lower stratosphere, at pressure levels ranging from 0.5 bar to 0.4 mbar. The CH4 emission band at 7.7 mu m and the H-2-He continuum longward of 11 mu m are used to retrieve the thermal profile, which is then used to derive the vertical distributions of minor species: NH3, PH3, CH3D in the troposphere, and C2H2 and C2H6 in the stratosphere. Estimates of the CO2, CH3C2H and C4H2 mean mixing ratios (above the 10-mbar level) are 3 10(-10), 6 10(-10) and 9 10(-11) respectively. The retrieved disk-averaged thermal profile is found to be colder in the stratosphere than the Voyager 1 ingress radio-occultation profile by about 7 K at P = 0.5 mbar, and slightly warmer in the troposphere (about 5 K at 400 mbar and 3 K at 150 mb).

The spectrum of Jupiter has been recorded between 2.75 and 14.5 mu m with the grating mode of the Short-Wavelength Spectrometer (SWS) of ISO. The resolving power is 1500. The main preliminary results of this observation are (1) at 3 mu m, the first spectroscopic signature, probably associated with NH3 ice, of the Jovian cloud at 0.5 bar and (2) the first detection of a thermal emission at the center of the CH4-nu(3) band at 3.3 mu m, showing evidence for a high temperature in the upper jovian stratosphere (T=800 K at P=0.16 microbar). In addition, the R(2) HD line has been detected for the first time in Jupiter, using the Fabry-Perot (FP) mode of the SWS, with a resolving power of 31000. A preliminary analysis of the HD line indicates a D/H ratio of about 2.2 10(-5).

The first detection of thermal water emission from a Herbig-Haro object is presented. The observations were performed with the LWS (Long Wavelength Spectrograph) aboard ISO (Infrared Space Observatory). Besides H2O, rotational lines of CO are present in the spectrum of HH 54. These high-J CO lines are used to derive the physical model parameters of the FIR (far-infrared) molecular line emitting regions. This model fits simultaneously the observed OH and H2O spectra for an OH abundance X(OH)=10-6 and a water vapour abundance X(H2O)=10-5. \ud \ud At a distance of 250pc, the total CO, OH and H2O rotational line cooling rate is estimated to be 1.3x10-2 L⊙, which is comparable to the mechanical luminosity generated by the 10km s-1 shocks, suggesting that practically all of the cooling of the weak-shock regions is done by these three molecular species alone.