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We present 850 μm polarimetric observations toward the Serpens Main molecular cloud obtained using the POL-2 polarimeter on the James Clerk Maxwell Telescope as part of the B-fields In STar-forming Region Observations survey. These observations probe the magnetic field morphology of the Serpens Main molecular cloud on about 6000 au scales, which consists of cores and six filaments with different physical properties such as density and star formation activity. Using the histogram of relative orientation (HRO) technique, we find that magnetic fields are parallel to filaments in less-dense filamentary structures where N H 2 < 0.93 × 10 22 cm−2 (magnetic fields perpendicular to density gradients), while they are perpendicular to filaments (magnetic fields parallel to density gradients) in dense filamentary structures with star formation activity. Moreover, applying the HRO technique to denser core regions, we find that magnetic field orientations change to become perpendicular to density gradients again at N H 2 ≈ 4.6 × 10 22 cm−2. This can be interpreted as a signature of core formation. At N H 2 ≈ 16 × 10 22 cm−2, magnetic fields change back to being parallel to density gradients once again, which can be understood to be due to magnetic fields being dragged in by infalling material. In addition, we estimate the magnetic field strengths of the filaments (B POS = 60–300 μG)) using the Davis–Chandrasekhar–Fermi method and discuss whether the filaments are gravitationally unstable based on magnetic field and turbulence energy densities.

We present the results of simultaneous 450 μm and 850 μm polarization observations toward the massive star-forming region NGC 2071IR, a target of the BISTRO (B-fields in STar-forming Region Observations) Survey, using the POL-2 polarimeter and SCUBA-2 camera mounted on the James Clerk Maxwell Telescope. We find a pinched magnetic field morphology in the central dense core region, which could be due to a rotating toroidal disklike structure and a bipolar outflow originating from the central young stellar object IRS 3. Using the modified Davis–Chandrasekhar–Fermi method, we obtain a plane-of-sky magnetic field strength of 563 ± 421 μG in the central ∼0.12 pc region from 850 μm polarization data. The corresponding magnetic energy density of 2.04 × 10−8 erg cm−3 is comparable to the turbulent and gravitational energy densities in the region. We find that the magnetic field direction is very well aligned with the whole of the IRS 3 bipolar outflow structure. We find that the median value of polarization fractions is 3.0% at 450 μm in the central 3′ region, which is larger than the median value of 1.2% at 850 μm. The trend could be due to the better alignment of warmer dust in the strong radiation environment. We also find that polarization fractions decrease with intensity at both wavelengths, with slopes, determined by fitting a Rician noise model of 0.59 ± 0.03 at 450 μm and 0.36 ± 0.04 at 850 μm, respectively. We think that the shallow slope at 850 μm is due to grain alignment at the center being assisted by strong radiation from the central young stellar objects.

Context. Molecular filaments and hubs have received special attention recently thanks to new studies showing their key role in star formation. While the (column) density and velocity structures of both filaments and hubs have been carefully studied, their magnetic field (B-field) properties have yet to be characterized. Consequently, the role of B-fields in the formation and evolution of hub-filament systems is not well constrained. Aims. We aim to understand the role of the B-field and its interplay with turbulence and gravity in the dynamical evolution of the NGC 6334 filament network that harbours cluster-forming hubs and high-mass star formation. Methods. We present new observations of the dust polarized emission at 850 μm toward the 2 pc × 10 pc map of NGC 6334 at a spatial resolution of 0.09 pc obtained with the James Clerk Maxwell Telescope (JCMT) as part of the B-field In STar-forming Region Observations (BISTRO) survey. We study the distribution and dispersion of the polarized intensity (PI), the polarization fraction (PF), and the plane-of-the-sky B-field angle (χB_POS) toward the whole region, along the 10 pc-long ridge and along the sub-filaments connected to the ridge and the hubs. We derived the power spectra of the intensity and χBPOS along the ridge crest and compared them with the results obtained from simulated filaments. Results. The observations span ~3 orders of magnitude in Stokes I and PI and ~2 orders of magnitude in PF (from ~0.2 to ~ 20%). A large scatter in PI and PF is observed for a given value of I. Our analyses show a complex B-field structure when observed over the whole region (~ 10 pc); however, at smaller scales (~1 pc), χBPOS varies coherently along the crests of the filament network. The observed power spectrum of χBPOS can be well represented with a power law function with a slope of − 1.33 ± 0.23, which is ~20% shallower than that of I. We find that this result is compatible with the properties of simulated filaments and may indicate the physical processes at play in the formation and evolution of star-forming filaments. Along the sub-filaments, χBPOS rotates frombeing mostly perpendicular or randomly oriented with respect to the crests to mostly parallel as the sub-filaments merge with the ridge and hubs. This variation of the B-field structure along the sub-filaments may be tracing local velocity flows of infalling matter in the ridge and hubs. Our analysis also suggests a variation in the energy balance along the crests of these sub-filaments, from magnetically critical or supercritical at their far ends to magnetically subcritical near the ridge and hubs. We also detect an increase in PF toward the high-column density (NH2 ≳ 1023 cm−2) star cluster-forming hubs. These latter large PF values may be explained by the increase in grain alignment efficiency due to stellar radiation from the newborn stars, combined with an ordered B-field structure. Conclusions. These observational results reveal for the first time the characteristics of the small-scale (down to ~ 0.1 pc) B-field structure of a 10 pc-long hub-filament system. Our analyses show variations in the polarization properties along the sub-filaments that may be tracing the evolution of their physical properties during their interaction with the ridge and hubs. We also detect an impact of feedback from young high-mass stars on the local B-field structure and the polarization properties, which could put constraints on possible models for dust grain alignment and provide important hints as to the interplay between the star formation activity and interstellar B-fields.

The latest generation of Galactic Plane surveys is enhancing our ability to study the effects of galactic environment upon the process of star formation. We present the first data from CO Heterodyne Inner Milky Way Plane Survey 2 (CHIMPS2). CHIMPS2 is a survey that will observe the Inner Galaxy, the Central Molecular Zone (CMZ), and a section of the Outer Galaxy in 12CO, 13CO, and C18O (J = 3 → 2) emission with the Heterodyne Array Receiver Program on the James Clerk Maxwell Telescope (JCMT). The first CHIMPS2 data presented here are a first look towards the CMZ in 12CO J = 3 → 2 and cover −3◦ ≤ ≤ 5◦ and | b | ≤ 0. ◦5 with angular resolution of 15 arcsec, velocity resolution of 1 km s−1, and rms T ∗ A = 0.58 K at these resolutions. Such high-resolution observations of the CMZ will be a valuable data set for future studies, whilst complementing the existing Galactic Plane surveys, such as SEDIGISM, the Herschel infrared Galactic Plane Survey, and ATLASGAL. In this paper, we discuss the survey plan, the current observations and data, as well as presenting position–position maps of the region. The position–velocity maps detect foreground spiral arms in both absorption and emission.

SPICA Science Conference from Exoplanets to Distant Galaxies: SPICA's New Window on the Cool Universe (June 18-21, 2013. Ito Hall, the University of Tokyo), Bunkyou-ku, Tokyo, Japan, Typical galaxies emit about one third of their energy in the infrared. The origin of this emission reprocessed starlight absorbed by interstellar dust grains and reradiated as thermal emission in the infrared. In particularly dusty galaxies, such as starburst galaxies, the fraction of energy emitted in the infrared can be as high as 90%. Dust emission is found to be an excellent tracer of the beginning and end stages of a star’s life, where dust is being produced by post-main-sequence stars, subsequently added to the interstellar dust reservoir, and eventually being consumed by star and planet formation. This work reviews the current understanding of the size and properties of this interstellar dust reservoir, by using the Large Magellanic Cloud as an example, and what can be learned about the dust properties and star formation in galaxies from this dust reservoir, using SPICA, building on previous work performed with the Herschel and Spitzer Space Telescopes, as well as the Infrared Space Observatory., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA1730027043, レポート番号: JAXA-SP-17-010E

著者人数: The B-fields In STar-forming Regions Observations (BISTRO) Collaboration 121名 (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 權, 靜美), Number of authors: The B-fields In STar-forming Regions Observations (BISTRO) Collaboration 121 (Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS): Kwon, Jungmi), Accepted: 2019-04-18, 資料番号: SA1190042000

The SPICA mid and far-infrared telescope will address fundamental issues in our understanding of star formation and ISM physics in galaxies. A particular hallmark of SPICA is the outstanding sensitivity enabled by the cold telescope, optimized detectors, and wide instantaneous bandwidth throughout the mid- and far-infrared. The spectroscopic, imaging and polarimetric observations that SPICA will be able to collect will help in clarifying the complex physical mechanisms which underlie the baryon cycle of galaxies. In particular: (i) The access to a large suite of atomic and ionic fine-structure lines for large samples of galaxies will shed light on the origin of the observed spread in star formation rates within and between galaxies. (ii) Observations of HD rotational lines (out to $\sim$10 Mpc) and fine structure lines such as [CII] 158 $\mu$m (out to $\sim$100 Mpc) will clarify the main reservoirs of interstellar matter in galaxies, including phases where CO does not emit. (iii) Far-infrared spectroscopy of dust and ice features will address uncertainties in the mass and composition of dust in galaxies, and the contributions of supernovae to the interstellar dust budget will be quantified by photometry and monitoring of supernova remnants in nearby galaxies. (iv) Observations of far-infrared cooling lines such as [OI] 63 $\mu$m from star-forming molecular clouds in our Galaxy will evaluate the importance of shocks to dissipate turbulent energy. The paper concludes with requirements for the telescope and instruments, and recommendations for the observing strategy., Comment: Accepted for publication in PASA; 19 pages, 8 figures, 1 table

The Infrared Spectrograph (IRS) on the {\em Spitzer Space Telescope} observed nearly 800 point sources in the Large Magellanic Cloud (LMC), taking over 1,000 spectra. 197 of these targets were observed as part of the Sage-Spec Spitzer Legacy program; the remainder are from a variety of different calibration, guaranteed time and open time projects. We classify these point sources into types according to their infrared spectral features, continuum and spectral energy distribution shape, bolometric luminosity, cluster membership, and variability information, using a decision-tree classification method. We then refine the classification using supplementary information from the astrophysical literature. We find that our IRS sample is comprised substantially of YSO and H\,{\sc ii} regions, post-Main Sequence low-mass stars: (post-)AGB stars and planetary nebulae and massive stars including several rare evolutionary types. Two supernova remnants, a nova and several background galaxies were also observed. We use these classifications to improve our understanding of the stellar populations in the Large Magellanic Cloud, study the composition and characteristics of dust species in a variety of LMC objects, and to verify the photometric classification methods used by mid-IR surveys. We discover that some widely-used catalogues of objects contain considerable contamination and others are missing sources in our sample., Comment: Accepted for publication in MNRAS

We present the first results from the B-fields In STar-forming Region Observations (BISTRO) survey, using the Sub-millimetre Common-User Bolometer Array 2 camera, with its associated polarimeter (POL-2), on the James Clerk Maxwell Telescope in Hawaii. We discuss the survey's aims and objectives. We describe the rationale behind the survey, and the questions that the survey will aim to answer. The most important of these is the role of magnetic fields in the star formation process on the scale of individual filaments and cores in dense regions. We describe the data acquisition and reduction processes for POL-2, demonstrating both repeatability and consistency with previous data. We present a first-look analysis of the first results from the BISTRO survey in the OMC 1 region. We see that the magnetic field lies approximately perpendicular to the famous "integral filament" in the densest regions of that filament. Furthermore, we see an "hourglass" magnetic field morphology extending beyond the densest region of the integral filament into the less-dense surrounding material, and discuss possible causes for this. We also discuss the more complex morphology seen along the Orion Bar region. We examine the morphology of the field along the lower-density northeastern filament. We find consistency with previous theoretical models that predict magnetic fields lying parallel to low-density, non-self-gravitating filaments, and perpendicular to higher-density, self-gravitating filaments., Includes Horizon 2020 and STFC.

We present the rst results from the B- elds In STar-forming Region Observations (BISTRO) survey, using the Sub-millimetre Common-User Bolometer Array 2 (SCUBA-2) camera, with its associated polarimeter (POL-2), on the James Clerk Maxwell Telescope (JCMT) in Hawaii. We discuss the survey's aims and objectives. We describe the rationale behind the survey, and the questions which the survey will aim to answer. The most important of these is the role of magnetic fields in the star formation process on the scale of individual filaments and cores in dense regions. We describe the data acquisition and reduction processes for POL-2, demonstrating both repeatability and consistency with previous data. We present a first-look analysis of the rst results from the BISTRO survey in the OMC 1 region. We see that the magnetic field lies approximately perpendicular to the famous `integral filament' in the densest regions of that filament. Furthermore, we see an `hour-glass' magnetic field morphology extending beyond the densest region of the integral filament into the less-dense surrounding material, and discuss possible causes for this. We also discuss the more complex morphology seen along the Orion Bar region. We examine the morphology of the field along the lower-density north-eastern filament. We find consistency with previous theoretical models that predict magnetic fields lying parallel to low-density, non-self-gravitating filaments, and perpendicular to higher-density, self-gravitating filaments.

In this contribution in situ emission filter generation for, e.g. fluorescence light detection by morphology tailoring of silver nanoparticles within a polymer layer, is presented for the first time. After depositing a pretreated film of polyethylenimine containing spherical silver nanoparticles the composite layer was irradiated with green LEDs (peak wavelength 530 nm). This leads to a morphology change of the silver nanoparticles and therefore to a change in absorption properties of the resulting polymer film with an absorption maximum at 550 nm. This tailoring of silver nanoparticles embedded in a transparent polymer matrix could address many novel applications such as adaptable light filters for future lab-on-a-chip applications. A LED for fluorescence light excitation was used to illuminate the silver nanoparticles, which led to an increasing absorption of that particular light spectrum, and therefore in situ produced a fluorescence emission filter. The effect of the treatment time, the silver ion concentration, and the temperature at which the "light-shaping" was done was studied. The silver nanoparticles were investigated using UV/Vis-spectroscopy and scanning electron microscopy. The observed nanoparticle shapes give reasons for a novel hypothesis of nanoparticle evolution. The forced plasmon oscillation seems to cause excited regions at the silver nanoparticles where adsorbed silver ions are preferably photoreduced. This results in the possibility of tailoring the morphology and therefore the optical properties of the growing nanoparticles.

Organic light emitting diodes (OLEDs) have the advantages of self-emitting property, high luminous efficiency, full-colour capability, wide viewing angle, high contrast, low power consumption, low weight and flexibility. All these capacitate OLEDs to be an attractive optical source for display and lighting applications. However, the current manufacturing cost is still relative high, which obstacle its success in the display and lighting market. The main problems are indispensable low work function material for cathode and/or electron injection layer such as Ba, LiF, which require vacuum deposition and/or inert fabrication atmosphere, and widely used anode ITO which are not solution processable. Therefore, the fully solution processing manufacturing techniques are under intense investigation in order to reduce the cost. Compared to OLEDs, its derivation, organic light-emitting electrochemical cells (OLECs), show an intrinsic advantage in fully solution processing. By mixing metal ions and a solid electrolyte with light-emitting polymers as active materials, an in-situ doping and in-situ PN-junction can be generated within a three layer sandwich device. Because of this doping effect, work function adaption is not necessary and air-stable flexible electrodes like PEDOT:PSS can be used. Hereby, a manufacturing process for fully solution-processed transparent OLECs is presented, which consist of inkjet printed PEDOT:PSS anode and cathode, spin-coated ZnO interlayer, and spin-coated yellow light-emitting polymer plus dopant. Inkjet printing the electrode give the advantages of mask-free and spin-coating provides the homogeneous active layers. Furthermore, by manufacturing on 70 mm thin glass, a relative flexible transparent light source can be realized and enable the potential emerging applications like signal display on textiles.

We report the first fluorescence light detector combining a fully solution processed organic electrochemical cell (OLEC) and a fully solution processed organic photodiode (OPD) within one microfluidic chip. The blue OLEC was used as the excitation source, whereas the OPD was used for detection of the emitted fluorescent light. Two orthogonally oriented linear polarizers were used as excitation and emission filters, enabling the use of fluorescent dyes with emission and absorption peaks very close to each other. In addition the system is compatible with many different fluorescent dyes. The filters and organic devices were mounted onto a microfluidic glass chip. Fluorescein amidite (FAM) was used as a model dye to characterize and demonstrate the concept of the system. Despite a very close excitation peak (492 nm) and emission peak (518 nm) of FAM, we were able to detect FAM concentrations as low as 1 mM even for a brightness value of the OLEC as low as 500 cd m -2. This opens the possibility of producing low cost, portable and disposable fluorescence sensors with a high sensitivity.

In this contribution, two approaches of the solution processing of novel spectral light filters are demonstrated. The first approach shows the combination of light filtering capability with electrical conductivity in a "light filter electrode" by mixing colorants into poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) ink. Different colorants are investigated concerning their influence on the workfunction and the electrical conductivity of the resulting PEDOT:PSS layers. In addition, these electrodes could be integrated into organic photodiodes, opening up the possibility of using the whole device for specific light detection. Within the second approach, the surface plasmon resonance and the scattering of metal nanoparticles is used for light filtering. Light scattering (and therefore the reflection of excitation light back into the microfluidic channel) increases the excitation efficiency, thus increasing the intensity of the fluorescent light. With this approach, the sensitivity of the demonstrated light detectors can effectively be increased while simultaneously decreasing the detection limit of the substance of interest.

A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to make accurate images with resolutions of tens of milliarcseconds, which at submillimeter (submm) wavelengths requires baselines up to ~15 km. To develop and test this capability, a Long Baseline Campaign (LBC) was carried out from September to late November 2014, culminating in end-to-end observations, calibrations, and imaging of selected Science Verification (SV) targets. This paper presents an overview of the campaign and its main results, including an investigation of the short-term coherence properties and systematic phase errors over the long baselines at the ALMA site, a summary of the SV targets and observations, and recommendations for science observing strategies at long baselines. Deep ALMA images of the quasar 3C138 at 97 and 241 GHz are also compared to VLA 43 GHz results, demonstrating an agreement at a level of a few percent. As a result of the extensive program of LBC testing, the highly successful SV imaging at long baselines achieved angular resolutions as fine as 19 mas at ~350 GHz. Observing with ALMA on baselines of up to 15 km is now possible, and opens up new parameter space for submm astronomy., 11 pages, 7 figures, 2 tables; accepted for publication in the Astrophysical Journal Letters; this version with small changes to affiliations

This paper reports variations of polycyclic aromatic hydrocarbons (PAHs) features that were found in Spitzer Space Telescope spectra of carbon-rich post-asymptotic giant branch (post-AGB) stars in the Large Magellanic Cloud (LMC). The paper consists of two parts. The first part describes our Spitzer spectral observing programme of 24 stars including post-AGB candidates. The latter half of this paper presents the analysis of PAH features in 20 carbon-rich post-AGB stars in the LMC, assembled from the Spitzer archive as well as from our own programme. We found that five post-AGB stars showed a broad feature with a peak at 7.7 micron, that had not been classified before. Further, the 10--13 micron PAH spectra were classified into four classes, one of which has three broad peaks at 11.3, 12.3 and 13.3 micron rather than two distinct sharp peaks at 11.3 and 12.7 micron, as commonly found in HII regions. Our studies suggest that PAHs are gradually processed while the central stars evolve from post-AGB phase to PNe, changing their composition before PAHs are incorporated into the interstellar medium. Although some metallicity dependence of PAH spectra exists, the evolutionary state of an object is more significant than its metallicity in determining the spectral characteristics of PAHs for LMC and Galactic post-AGB stars., Accepted by MNRAS

We searched the Spitzer Space Telescope data archive for Galactic planetary nebulae (PNe), that show the characteristic 17.4 and um features due to C60, also known as buckminsterfullerene. Out of 338 objects with Spitzer/IRS data, we found eleven C60-containing PNe, six of which (Hen2-68, IC2501, K3-62, M1-6, M1-9, and SaSt2-3) are new detections. We analyzed the spectra, along with ancillary data, using the photo-ionization code CLOUDY to establish the atomic line fluxes, and determine the properties of the radiation field, as set by the effective temperature of the central star. In addition, we measured the infrared spectral features due to dust grains. We find that the Polycyclic Aromatic Hydrocarbon (PAH) profile over 6-9 um in these C60-bearing carbon-rich PNe is of the more chemically-processed class A. The intensity ratio of 3.3 um to 11.3 um PAH indicates that the number of C-atoms per PAH in C60-containing PNe is small compared to that in non-C60 PNe. The Spitzer spectra also show broad dust features around 11 and 30 um. Analysis of the 30-um feature shows that it is strongly correlated with the continuum, and we propose that a single carbon-based carrier is responsible for both the continuum and the feature. The strength of the 11-um feature is correlated to the temperature of the dust, suggesting that it is at least partially due to a solid-state carrier. The chemical abundances of C60-containing PNe can be explained by AGB nucleosynthesis models for initially 1.5-2.5 Msun stars with Z=0.004. We plotted the locations of C60-containing PNe on a face-on map of the Milky Way and we found that most of these PNe are outside the solar circle, consistent with low metallicity values. Their metallicity suggests that the progenitors are an older population., Comment: 18 pages, 13 figures, 13 tables, Accepted for publication by MNRAS

K-band spectra are presented for a sample of 39 Spitzer IRS SAGE-Spec sources in the Large Magellanic Cloud. The spectra exhibit characteristics in very good agreement with their positions in the near infrared - Spitzer color-magnitude diagrams and their properties as deduced from the Spitzer IRS spectra. Specifically, the near infrared spectra show strong atomic and molecular features representative of oxygen-rich and carbon-rich asymptotic giant branch stars, respectively. A small subset of stars were chosen from the luminous and red extreme "tip" of the color magnitude diagram. These objects have properties consistent with dusty envelopes but also cool, carbon-rich "stellar" cores. Modest amounts of dust mass loss combine with the stellar spectral energy distribution to make these objects appear extreme in their near infrared and mid infrared colors. One object in our sample, HV 915, a known post asymptotic giant branch star of the RV Tau type exhibits CO 2.3 micron band head emission consistent with previous work that demonstrates the object has a circumstellar disk., Comment: 32 pages, 12 figures (eps), accepted for publication in the AJ

We present the various science cases for building Band 1 receivers as part of ALMA's ongoing Development Program. We describe the new frequency range for Band 1 of 35-52 GHz, a range chosen to maximize the receiver suite's scientific impact. We first describe two key science drivers: 1) the evolution of grains in protoplanetary disks and debris disks, and 2) molecular gas in galaxies during the era of re-ionization. Studies of these topics with Band 1 receivers will significantly expand ALMA's Level 1 Science Goals. In addition, we describe a host of other exciting continuum and line science cases that require ALMA's high sensitivity and angular resolution. For example, ALMA Band 1 continuum data will probe the Sunyaev-Zel'dovich Effect in galaxy clusters, Very Small Grains and spinning dust, ionized jets from young stars, spatial and flaring studies of Sgr A*, the acceleration sites of solar flares, pulsar wind nebulae, radio supernovae, and X-ray binaries. Furthermore, ALMA Band 1 line data will probe chemical differentiation in cloud cores, complex carbon chain molecules, extragalactic radio recombination lines, masers, magnetic fields through Zeeman effect measurements, molecular outflows from young stars, the co-evolution of star formation and active galactic nuclei, and the molecular content of galaxies at z ~ 3. ALMA provides similar to better sensitivities than the JVLA over 35-50 GHz, with differences increasing with frequency. ALMA's smaller antennas and shorter baselines, greater number of baselines, and single-dish capabilities, however, give it a significant edge for observing extended emission, making wide-field maps (mosaics), or attaining high image fidelity, as required by the described science cases., 74 pages; this document is a major revision of one posted previously as arXiv:0910.1609

Gevolmachtigd agenten voeren namens verzekeraars diensten uit op het gebied van acceptatie, polisbeheer, portefeuillemanagement en schadeafhandeling. Ze fungeren als schakelpunt tussen verzekeraars en bemiddelaars, en combineren de slagkracht van de verzekeraars met de korte afstand tot de markt van bemiddelaars. Gevolmachtigd agenten worden voor hun diensten beloond met verschillende soorten commissies en vergoedingen. In de optiek van de Nederlandse Vereniging van Gevolmachtigde Assurantiebedrijven (NVGA) en het Verbond van Verzekeraars is het bestaande vergoedingstelsel aan herijking toe. De NVGA en het Verbond van Verzekeraars hebben SEO Economisch Onderzoek en SVC daarom gevraagd om in samenwerking een inventariserend onderzoek te doen naar de mogelijkheden van een eenduidige, passende volmachtbeloning die voldoet aan eisen van transparantie, passendheid en bruikbaarheid. Dit rapport geeft de bevindingen weer. De uitkomsten bieden marktpartijen een kader waarbinnen ze een nieuwe beloningssystematiek kunnen ontwikkelen.

The SAGE-Spectroscopy Spitzer legacy program (SAGE-Spec; PI: F. Kemper, PID: 40159; Kemper et al. 2010) is the IRS spectroscopic follow-up to the successful SAGE-LMC legacy program (Meixner et al. 2006; PI: M. Meixner, PID: 20203) that mapped the Large Magellanic Cloud (LMC) with all bands of the IRAC and MIPS instruments on board the Spitzer Space Telescope. This technical document gives details of the data-reduction procedure and the various data products that are publicly available through IRSA: http://irsa.ipac.caltech.edu/data/SPITZER/SAGE/, 40 pages, 1 figure, data delivery document to accompany the public release of SAGE-Spec data

We present a diagnostic tool to determine the forsterite abundance of the dust ejected by AGB stars. Our method is based on a comparison between the observed strength of spectral bands of forsterite and model calculations. We show that the 11.3 {\mu}m forsterite band is a robust indicator of the forsterite abundance of the current mass-loss period for AGB stars with an optically thick dust shell. The 33.6 {\mu}m band of forsterite is sensitive to changes in the density and the geometry of the emitting dust shell, and so a less robust indicator. We apply this method to six high mass-loss rate AGB stars, showing that AGB stars can have forsterite abundances of 12% by mass and higher, which is more than the previously found maximum abundance of 5%.

著者人数: 60名, Accepted: 2011-07-17, 資料番号: SA1003632000

We present a diagnostic tool to determine the forsterite abundance of the dust ejected by AGB stars. Our method is based on a comparison between the observed strength of spectral bands of forsterite and model calculations. We show that the 11.3 {\mu}m forsterite band is a robust indicator of the forsterite abundance of the current mass-loss period for AGB stars with an optically thick dust shell. The 33.6 {\mu}m band of forsterite is sensitive to changes in the density and the geometry of the emitting dust shell, and so a less robust indicator. We apply this method to six high mass-loss rate AGB stars, showing that AGB stars can have forsterite abundances of 12% by mass and higher, which is more than the previously found maximum abundance of 5%.

We present a model using the evolution of the stellar population in a starburst galaxy to predict the crystallinity of the silicates in the interstellar medium of this galaxy. We take into account dust production in stellar ejecta, and amorphisation and destruction in the interstellar medium and find that a detectable amount of crystalline silicates may be formed, particularly at high star formation rates, and in case supernovae are efficient dust producers. We discuss the effect of dust destruction and amorphisation by supernovae, and the effect of a low dust-production efficiency by supernovae, and find that when taking this into account, crystallinity in the interstellar medium becomes hard to detect. Levels of 6.5-13% crystallinity in the interstellar medium of starburst galaxies have been observed and thus we conclude that not all these crystalline silicates can be of stellar origin, and an additional source of crystalline silicates associated with the Active Galactic Nucleus must be present., 8 pages, 6 figures, accepted by MNRAS

We present the comparison of the three most important ice constituents (water, CO and CO2) in the envelopes of massive Young Stellar Objects (YSOs), in environments of different metallicities: the Galaxy, the Large Magellanic Cloud (LMC) and, for the first time, the Small Magellanic Cloud (SMC). We present observations of water, CO and CO2 ice in 4 SMC and 3 LMC YSOs (obtained with Spitzer-IRS and VLT/ISAAC). While water and CO2 ice are detected in all Magellanic YSOs, CO ice is not detected in the SMC objects. Both CO and CO2 ice abundances are enhanced in the LMC when compared to high-luminosity Galactic YSOs. Based on the fact that both species appear to be enhanced in a consistent way, this effect is unlikely to be the result of enhanced CO2 production in hotter YSO envelopes as previously thought. Instead we propose that this results from a reduced water column density in the envelopes of LMC YSOs, a direct consequence of both the stronger UV radiation field and the reduced dust-to-gas ratio at lower metallicity. In the SMC the environmental conditions are harsher, and we observe a reduction in CO2 column density. Furthermore, the low gas-phase CO density and higher dust temperature in YSO envelopes in the SMC seem to inhibit CO freeze-out. The scenario we propose can be tested with further observations., accepted by MNRAS Letters; 5 pages, 3 figures, 1 table

We present the classification of 197 point sources observed with the Infrared Spectrograph in the SAGE-Spec Legacy program on the Spitzer Space Telescope. We introduce a decision-tree method of object classification based on infrared spectral features, continuum and spectral energy distribution shape, bolometric luminosity, cluster membership, and variability information, which is used to classify the SAGE-Spec sample of point sources. The decision tree has a broad application to mid-infrared spectroscopic surveys, where supporting photometry and variability information are available. We use these classifications to make deductions about the stellar populations of the Large Magellanic Cloud and the success of photometric classification methods. We find 90 asymptotic giant branch (AGB) stars, 29 young stellar objects, 23 post-AGB objects, 19 red supergiants, eight stellar photospheres, seven background galaxies, seven planetary nebulae, two HII regions and 12 other objects, seven of which remain unclassified., (43 pages, 21 figures, 4 tables including one large table out of order; to be published in MNRAS)

Contains fulltext : 84097.pdf (Author’s version preprint ) (Open Access) Contains fulltext : 84097.pdf (Publisher’s version ) (Open Access)

In dit hoofdstuk laten we zien dat sport zowel verenigt als verdeelt. Sport versterkt bestaande sociale netwerken, maar sluit ook bepaalde groepen uit. Bovendien vergroot sport onderlinge competitiegevoelens die op hun beurt kunnen leiden tot onsportief en zelfs agressief gedrag. Sportdeelname is ook niet kleurenblind of klasseloos, sportparticipatie verloopt veelal langs gevestigde sociale scheidslijnen. In prestatieverband krijgen ontmoetingen tussen verschillende sociale milieus gestalte doordat de besten, ongeacht sociale achtergrond, bij elkaar worden geplaatst. Bij recreanten liggen dergelijke ontmoetingen minder voor het oprapen, maar toch zijn er ook hier wel gelegenheden voor interetnische interactie. Dit leidt tot meer contact, ook al blijft dat contact vaak ppervlakkig. Het is eigen aan de aard van sport als vrijetijdsactiviteit dat het een belangrijke rol speelt bij het ontwikkelen en in stand houden van de eigen identiteit. De wens om onder elkaar te verkeren is vaak een positieve keus. Schaduwkant hiervan is dat de hieruit resulterende lichte gemengde contacten in de sport minder dan gehoopt de beeldvorming over en weer tussen sociale groepen veranderen. Bij intensievere omgang in een gemeenschappelijk verband is daar meer kans op (bijvoorbeeld bij prestatiesport). ‘Sport verbroedert’, maar we mogen het effect niet overschatten.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 2416-2420, To meet the projected market-demand for low-cost, high-performance PV modules, EPV SOLAR, Inc. has increased the average rated power of its standard module by over 28% to 54W. Key factors in this increase were the incorporation of a ZnO:Al/Al back reflector and a larger module size. To capture a larger market-share and to further lower costs, two additional manufacturing facilities have been constructed and brought on-line to bring the total EPV manufacturing capacity to 55 MW/yr. Diagnostic tools including non-destructive a-Si thickness mapping and IR imaging of defects have been developed to improve process control and further increase module performance. R&D efforts to increase performance have focused on improving the optical engineering of the device and the development of an a-Si/nc-Si hybrid structure. Significant results include the demonstration of >4% increase in short circuit current density through the use of a TiOx internal anti-reflective layer, and in collaboration with ENEA, a 9.9% a-Si/nc-Si hybrid tandem fabricated on textured ZnO:Al, sputtered from a reactive-environment hollow cathode sputtering source.

We present observations of Taurus-Auriga Class I/II protostars obtained with the Spitzer InfraRed Spectrograph. Detailed spectral fits to the 6 and 15 micron features are made, using publicly-available laboratory data, to constrain the molecular composition, abundances, and levels of thermal processing along the lines of sight. We provide an inventory of the molecular environments observed, which have an average composition dominated by water ice with ~12% CO_2 (abundance relative to H_2O), >~2-9% CH_3OH, Comment: Accepted to ApJ. 40 pages, 20 figures

Color-magnitude diagrams (CMDs) are presented for the Spitzer SAGE (Surveying the Agents of a Galaxy's Evolution) survey of the Large Magellanic Cloud (LMC). IRAC and MIPS 24 mu m epoch 1 data are presented. These data represent the deepest, widest mid-infrared CMDs of their kind ever produced in the LMC. Combined with the Two Micron All Sky Survey, the diagrams are used to delineate the evolved stellar populations in the LMC, as well as Galactic foreground and extragalactic background populations. Some 32,000 evolved stars brighter than the tip of the red giant branch are identified. Of these, approximately 17,500 are classified as oxygen-rich, 7000 as carbon-rich, and another 1200 as "extreme'' asymptotic giant branch (AGB) stars. Brighter members of the latter group have been called "obscured'' AGB stars in the literature owing to their dusty circumstellar envelopes. A large number (1200) of luminous oxygen-rich AGB stars/M supergiants are also identified. Finally, there is strong evidence from the 24 mu m MIPS channel that previously unexplored, lower luminosity oxygen-rich AGB stars contribute significantly to the mass-loss budget of the LMC (1200 such sources are identified).

We present 14--21 um emission spectra of star forming regions and compare them with the PAH spectra from the Ames PAH database. We show that while the emission in this region can be quite variable, the bulk of these variations can be accommodated by variations in the IS PAH population., Comment: conference proceedings of Spitzer New Views of the Cosmos, 2 pages

We present spectra of four Herbig AeBe stars obtained with the Infrared Spectrograph (IRS). on the Spitzer Space Telescope. All four of the sources show strong emission from polycyclic aromatic hydrocarbons (PAHs), with the 6.2 um emission feature shifted to 6.3 um and the strongest C-C skeletal-mode feature occuring at 7.9 um instead of at 7.7 um as is often seen. Remarkably, none of the four stars have silicate emission. The strength of the 7.9 um feature varies with respect to the 11.3 um feature among the sources, indicating that we have observed PAHs with a range of ionization fractions. The ionization fraction is higher for systems with hotter and brighter central stars. Two sources, HD 34282 and HD 169142, show emission features from aliphatic hydrocarbons at 6.85 and 7.25 um. The spectrum of HD 141569 shows a previously undetected emission feature at 12.4 um which may be related to the 12.7 um PAH feature. The spectrum of HD 135344, the coolest star in our sample, shows an unusual profile in the 7-9 um region, with the peak emission to the red of 8.0 um and no 8.6 um PAH feature., Accepted by ApJ 23 June, 2005, 8 pages (emulateapj), 5 figures (3 in color)

We present high resolution Spitzer spectroscopy of several pointings in the outflow of the Red Rectangle. Besides the resonances due to the C-rich PAHs, the spectra show a wealth of new emission bands, in particular in the 13-19.5 micron range. We argue that these bands are due to solid state components, and show that simple oxides of a varying composition show a good match to the data. The presence of these O-rich species in the supposedly C-rich outflow is unexplained., Comment: conference proceedings of Spitzer New Views of the Cosmos, 4 pages

We present 14--21 um emission spectra of star forming regions and compare them with the PAH spectra from the Ames PAH database. We show that while the emission in this region can be quite variable, the bulk of these variations can be accommodated by variations in the IS PAH population., conference proceedings of Spitzer New Views of the Cosmos, 2 pages

IRAS 16279-4757 belongs to a group of post-AGB stars showing both PAH bands and crystalline silicates. We present mid-infrared images, that resolve the object for the first time. The morphology is similar to that of the `Red Rectangle' (HD 44179), the prototype object with PAHs and crystalline silicates. A two-component model and images suggest a dense oxygen-rich torus, an inner, low-density carbon-rich region and a carbon-rich bipolar outflow. The PAH bands are enhanced at the outflow, while the continuum emission is concentrated towards the center. Our findings support the suggestion that mixed chemistry and morphology are closely related. We discuss the ISO/SWS spectra of IRAS 16279-4757. Several bands in the ISO/SWS spectrum show a match with anorthite: this would be the first detection of this mineral outside the solar system. Compared to HD 44179, the shapes of PAH bands are closer to those of planetary nebulae, possibly related to a population of small PAHs present HD 44179, but absent around IRAS 16279-4757. Detailed examination of the spectra shows the individual character of these two objects. The comparison suggests that the torus found in IRAS 16279-4757 may have formed more recently than that in HD 44179., Comment: accepted to ApJ

Infrared spectra of a number of evolved O-rich stars have been obtained with the Short- and Long- Wavelength spectrometers on board the Infrared Space Observatory. The very broad wavelength coverage (2.4-197 micron) obtained by combining observations made with the two spectrometers includes practically all of the flux emitted by the sources, and allows us to determine the emission and absorption features of the dense circumstellar dust shells. Agreement between the fluxes obtained by the two instruments is generally very good; the largest discrepancies are probably due to source variability. Our sample of oxygen-rich AGB stars exhibits a wealth of spectral features due to crystalline silicates and crystalline water ice in emission and absorption. In this study a qualitative overview of all features due to crystalline silicates and water ice in these high mass loss rate objects is presented. It seems that there is a certain onset value for the mass loss rate above which these features appear in the spectrum. Moreover, crystalline silicate emission features have been detected for the first time at wavelengths where the amorphous silicates are still in absorption, implying different spatial distributions for the two materials. A spherically symmetric and an axi-symmetric geometry are proposed., 7 figures, 15 pages. Accepted by A&A. A version with high resolution figures can be obtained from ftp://ceres.astro.uva.nl in directory /pub/ciska and is named H1687.ps