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Imaging spectroscopy, also known as integral field spectroscopy, is a valuable tool for analyzing extended ionized nebulae like planetary nebulae (PNe), H II regions, galaxies. PNe are the remnants of low to intermediate-mass stars (1-8 M⊙) that have expelled their outer layers. In this study, a two-dimensional spectroscopic analysis has been performed on the PN NGC 3132 using data from the MUSE. NGC 3132 was chosen for the early observing phase of the JWST, and multiple stellar system were discovered as well as significant molecular hydrogen emissions. Additionally, archival data from the Spitzer telescope were combined with JWST images to examine the radial distribution of near-infrared emission line ratios and IRAC colors. The average electron temperature of NGC 3132 was found close to, 9500 K, while the electron density ranges from 500 to 900 cm^(-3). Chemical composition variations in this nebular gas are ruled out. The radial analysis of optical and infrared lines shows a strong correlation between the c(Hβ) and emission lines, indicating the presence of significant amounts of dust that prevent molecular hydrogen dissociation. The physical and chemical properties of the nebula are mapped and compared to the predictions of a 3D photoionization model in order to constrain its physical characteristics.

Context. The Medium Resolution Spectrometer (MRS) is one of the four observing modes of JWST/MIRI. Using JWST in-flight data of unresolved (point) sources, we can derive the MRS absolute spectral response function (ASRF) starting from raw data. Spectral fringing, caused by coherent reflections inside the detector arrays, plays a critical role in the derivation and interpretation of the MRS ASRF. The fringe corrections implemented in the current pipeline are not optimal for non-extended sources, and a high density of molecular features particularly inhibits an accurate correction. Aims. In this paper, we present an alternative way to calibrate the MIRI/MRS data. Firstly, we derive a fringe correction that accounts for the dependence of the fringe properties on the MIRI/MRS pupil illumination and detector pixel sampling of the point spread function. Secondly, we derive the MRS ASRF using an absolute flux calibrator observed across the full 5- 28 µm wavelength range of the MRS. Thirdly, we apply the new ASRF to the spectrum of a G dwarf and compare it with the output of the JWST/MIRI default data reduction pipeline. Finally, we examine the impact of the different fringe corrections on the detectability of molecular features in the G dwarf and K giant. Methods. The absolute flux calibrator HD 163466 (A-star) was used to derive tailored point source fringe flats at each of the default dither locations of the MRS. The fringe-corrected point source integrated spectrum of HD 163466 was used to derive the MRS ASRF using a theoretical model for the stellar continuum. A cross-correlation was run to quantify the uncertainty on the detection of CO, SiO, and OH in the K giant and CO in the G dwarf for different fringe corrections. Results. The point-source-tailored fringe correction and ASRF are found to perform at the same level as the current corrections, beating down the fringe contrast to the sub-percent level in the G dwarf in the longer wavelengths, whilst mitigating the alteration of real molecular features. The same tailored solutions can be applied to other MRS unresolved targets. Target acquisition is required to ensure the pointing is accurate enough to apply this method. A pointing repeatability issue in the MRS limits the effectiveness of the tailored fringe flats is at short wavelengths. Finally, resulting spectra require no scaling to make the sub-bands match, and a dichroic spectral leak at 12.2 µm is removed., Astronomy & Astrophysics, 673, ISSN:0004-6361, ISSN:1432-0746

The ERC «ASSESS» project aims to determine whether episodic mass loss is a dominant process in the evolution of the most massive stars by conducting the first extensive, multi-wavelength survey of evolved massive stars in the nearby Universe. The project hinges on the fact that mass-losing stars form dust and are bright in the mid-infrared. We investigate the properties of evolved targets, selected by mid-infrared archival photometry from Spitzer, in ~25 nearby galaxies and estimate the amount of ejected mass, which will constrain evolutionary models. In this work we present our first results from the northern hemisphere survey, which includes the galaxies NGC 6822 and IC 10.

Context. Brown dwarfs are poorly understood transition objects between stars and planets, with several competing mechanisms having been proposed for their formation. Mass measurements are generally difficult for isolated objects but also for brown dwarfs orbiting low-mass stars, which are often too faint for spectroscopic follow-up. Aims. Microlensing provides an alternative tool for the discovery and investigation of such faint systems. Here we present the analysis of the microlensing event OGLE-2019-BLG-0033/MOA-2019-BLG-035, which is due to a binary system composed of a brown dwarf orbiting a red dwarf. Methods. Thanks to extensive ground observations and the availability of space observations from Spitzer, it has been possible to obtain accurate estimates of all microlensing parameters, including parallax, source radius and orbital motion of the binary lens. Results. After accurate modeling, we find that the lens is composed of a red dwarf with mass $M_1 = 0.149 \pm 0.010M_\odot$ and a brown dwarf with mass $M_2 = 0.0463 \pm 0.0031M_\odot$, at a projected separation of $a_\perp = 0.585$ au. The system has a peculiar velocity that is typical of old metal-poor populations in the thick disk. Percent precision in the mass measurement of brown dwarfs has been achieved only in a few microlensing events up to now, but will likely become common with the Roman space telescope., Comment: 13 pages, 6 figures

Hot Jupiters have cloudy and dynamic atmospheres, which can cause a planet's phase curve to vary from orbit to orbit. However, most hot Jupiter phase curves are only observed once. If the atmosphere is indeed changing, then we're missing something important! In this poster, I present the results of an analysis in which we observed two new phase curves of the hot Jupiter WASP-43 b, in addition to re-analyzing a previously observed phase curve of this planet. We found no variation between these three phase curves, allowing us to place an upper limit on the variability caused by cloud-driven weather.&nbsp

We present 850 $��$m polarimetric observations toward the Serpens Main molecular cloud obtained using the POL-2 polarimeter on the James Clerk Maxwell Telescope (JCMT) as part of the B-fields In STar-forming Region Observations (BISTRO) 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 $N_{H_2} < 0.93\times 10^{22}$ cm$^{-2}$ (magnetic fields perpendicular to density gradients), while being 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 $N_{H_2} \approx 4.6 \times 10^{22}$ cm$^{-2}$. This can be interpreted as a signature of core formation. At $N_{H_2} \approx 16 \times 10^{22}$ 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 ($B_{POS} = 60-300~��$G)) using the Davis-Chandrasekhar-Fermi method and discuss whether the filaments are gravitationally unstable based on magnetic field and turbulence energy densities., 18 pages, accepted for publication in ApJ

K2-141 b is a transiting, small (1.5 Re) ultra-short-period (USP) planet discovered by Kepler orbiting a K-dwarf host star every 6.7 hours. The planet's high surface temperature makes it an excellent target for thermal emission observations. Here we present 65 hours of continuous photometric observations of K2-141 b collected with Spitzer's IRAC Channel 2 at 4.5 micron spanning 10 full orbits of the planet. We measure an infrared eclipse depth of 143 +/- 39 ppm and a peak to trough amplitude variation of 121 +/- 43 ppm. The best fit model to the Spitzer data shows no significant thermal hotspot offset, in contrast to the previously observed offset for the well-studied USP planet 55 Cnc e. We also jointly analyze the new Spitzer observations with the photometry collected by Kepler during two separate K2 campaigns. We model the planetary emission with a range of toy models that include a reflective and a thermal contribution. With a two-temperature model, we measure a dayside temperature of 2049 +/- 361 K and a night-side temperature that is consistent with zero (Tp,n < 1712 K at 2 sigma). Models with a steep dayside temperature gradient provide a better fit to the data than a uniform dayside temperature (DeltaBIC = 22.2). We also find evidence for a non-zero geometric albedo Ag = 0.28 +/- 0.07. We also compare the data to a physically motivated, pseudo-2D rock vapor model and a 1D turbulent boundary layer model. Both models fit the data well. Notably, we find that the optical eclipse depth can be explained by thermal emission from a hot inversion layer, rather than reflected light. A thermal inversion may also be responsible for the deep optical eclipse observed for another USP, Kepler-10 b. Finally, we significantly improve the ephemerides for K2-141 b and c, which will facilitate further follow-up observations of this interesting system with state-of-the-art observatories like JWST., 31 pages, 27 figures, 12 tables, accepted for publication in A&A

This essay investigates the contribution of Auerbach's stylcritic to the elaboration of Pasolini's critical method. The paper focuses on three notions derived from Auerbach: mimesis, integrazione figurale (figural integration), adempimento (fulfillement); all concepts that aim to develop an idea of realism. So, Auerbach's contribution appears to be closely connected with that of Spitzer, although it is also, in Pasolini’s works, in partial contrast.

Les romans de Matilde Serao ont été largement traduits dans les pays germanophones à partir de la fin du XIXe siècle. En 1912, Leo Spitzer consacre à l’œuvre de Serao l’intégralité de sa leçon inaugurale à l’université de Vienne, soulignant en quoi l’autrice se distingue dans ses choix de vie et son travail, et louant l’œuvre remarquable qu’elle a produite. Publiée dans un périodique en 1914, cette leçon est envoyée par Spitzer à Benedetto Croce en signe de son amitié et de son intérêt pour la culture italienne., Matilde Serao’s novels were widely translated in German-speaking countries starting from the end of the nineteenth century. In 1912, Leo Spitzer devoted his inaugural lecture at the University of Vienna entirely to Serao’s oeuvre, underlining the idiosyncrasies between her life choices and her work, and noting the remarkable art she had produced. Published in a periodical in 1914, Spitzer sent the lecture to Benedetto Croce as a token of his friendship and his interest toward Italian culture.

Until now, our knowledge of the extragalactic Universe at mid-IR wavelengths (> 5 microns) was limited to rare active galactic nuclei (AGN) and the brightest normal galaxies up to z~3. The advent of the JWST with its Mid-Infrared Instrument (MIRI) will revolutionise the ability of the mid-IR regime as a key wavelength domain to probe the high-z Universe. In this work we present a first study of JWST MIRI 7.7 micron sources selected with > 3 sigma significance from the lensing cluster field SMACS J0723.3-7327. We model their spectral energy distribution fitting with 13 JWST and HST broad bands, in order to obtain photometric redshifts and derived physical parameters for all these sources. We find that this 7.7 micron galaxy sample is mainly composed of normal galaxies up to z=4 and has a tail of about 2% of sources at higher redshifts to z~ 9-10. The vast majority of our galaxies have [3.6]-[7.7], 13 pages, 9 figures, 2 tables. Accepted for publication at the ApJ. In the current version we make the 7.7 micron source catalogue publicly available

The asymmetric transit light curves of hot Jupiters orbiting fast-rotating, early type stars encode information about the true spin-orbit angle Ψ: a parameter that eludes measurement using most other methods. However, an accurate measurement of Ψ using from a transit is challenging, with numerous values for individual planets in literature exhibiting significant disagreement. Doppler tomography provides an alternative spectroscopy-based method which is less prone to bias, but only unlocks the sky-projected spin-orbit angle λ. I will present analyses of transit light curves for a sample of hot Jupiters with fast-rotating hosts acquired with CHEOPS, TESS, Kepler and Spitzer. The effect of fitting light curves acquired across the optical and IR with a single set of transit parameters greatly diminishes the degeneracies, and returns measurements of λ consistent with those from Doppler tomography. The placement of priors from tomography is better still, generally achieving improved precision on Ψ. With multi-colour light curves becoming available for ever-larger sections of the sky, this study provides a template for how to unveil the orbital architecture of these extreme systems and the underlying physical processes that shape them., {"references":["Myers, Samuel et al. (2019), EPSC-DPS2019-860 2019EPSC...13..860M","Johnson, Marshall C. et al. (2014), 10.1088/0004-637X/790/1/30","Masuda, Kento (2015), 10.1088/0004-637X/805/1/28","Parviainen, Hannu (2015), 10.1093/mnras/stv894","Talens, G. J. J. (2017), 10.1051/0004-6361/201731282"]}

In this paper, we extend the source detection in the GOODS-ALMA field (69 arcmin$^2$, rms sensitivity $\sigma$ $\simeq$ 0.18 mJy.beam$^{-1}$), to deeper levels than presented in Franco et al. (2018). Using positional information at 3.6 and 4.5 $\mu$m (from Spitzer-IRAC), we explore the presence of galaxies detected at 1.1 mm with ALMA below our original blind detection limit of 4.8-$\sigma$ at which the number of spurious sources starts to dominate over that of real sources. In this Supplementary Catalog, we find a total of 16 galaxies, including 2 galaxies with no counterpart in HST images (also known as optically-dark galaxies) down to a 5$\sigma$ limiting depth of H = 28.2 AB (HST/WFC3 F160W). This brings the total sample of GOODS-ALMA 1.1 mm sources to 35 galaxies. Galaxies in the new sample cover a wider dynamic range in redshift ($z$ = 0.65 - 4.73), are on average twice as large (1.3 vs 0.65 kpc) and and have lower stellar mass (M$_{\star}^{\rm SC}$ = 7.6$\times$10$^{10}$M$_\odot$ vs M$_{\star}^{\rm MC}$ = 1.2$\times$10$^{11}$M$_\odot$). Although exhibiting larger physical sizes, these galaxies have still far-infrared sizes significantly more compact than inferred from their optical emission. We show that the astrometry of the HST image does not only suffer from a global astrometric shift, as already discussed in previous papers, but also from local shifts. These distortions were artificially introduced in the process of building the mosaic of the GOODS-South HST image. By comparing the positions of almost 400 galaxies detected by HST, Pan-STARRS and ALMA, we create a distortion map which can be used to correct for these astrometric issues., Comment: 18 pages, 13 figures. Accepted for publication in A&A

International audience; The cosmic infrared background (CIB) provides a fundamental observational constraint on the star formation history of galaxies over cosmic history. We estimate the contribution to the CIB from catalogued galaxies in the COSMOS field by using a novel map fitting technique on the Herschel SPIRE maps. Prior galaxy positions are obtained using detections over a large range in wavelengths in the Ks-3 GHz range. Our method simultaneously fits the galaxies, the system foreground, and the leakage of flux from galaxies located in masked areas and corrects for an 'overfitting' effect not previously accounted for in stacking methods. We explore the contribution to the CIB as a function of galaxy survey wavelength and depth. We find high contributions to the CIB with the deep r (mAB ≤ 26.5), Ks (mAB ≤ 24.0), and 3.6 μm (mAB ≤ 25.5) catalogues. We combine these three deep catalogues and find a total CIB contributions of 10.5 ± 1.6, 6.7 ± 1.5, and 3.1 ± 0.7 nWm-2 sr-1 at 250, 350, and 500 μm, respectively. Our CIB estimates are consistent with recent phenomenological models, prior based SPIRE number counts and with (though more precise than) the diffuse total measured by FIRAS. Our results raise the interesting prospect that the CIB contribution at λ ≤ 500 μm from known galaxies has converged. Future large-area surveys like those with the Large Synoptic Survey Telescope are therefore likely to resolve a substantial fraction of the population responsible for the CIB at 250 μm ≤ λ ≤ 500 μm.

The last decade has seen the discovery of a growing population of planetary-mass companions (~Jup; hereafter PMCs) to young stars which are often still in the star-forming regions where they formed. These objects have been found at wide separations (>100 AU) from their host stars, challenging existing models of both star and planet formation. Demographic trends with mass and separation should distinguish between these formation models. The extensive Spitzer/IRAC data set of every major star-forming region and association within 300 pc has great potential to be mined for wide companions to stars. I will present new results from my automated pipeline to find wide-orbit companions of stars via point spread function (PSF) subtraction in Spitzer/IRAC images. A Markov Chain Monte Carlo algorithm is the backbone of this PSF subtraction routine that efficiently creates and subtracts χ2-minimizing instrumental PSFs, measuring infrared photometry of the systems across the four IRAC channels (3.6 μm, 4.5 μm, 5.8 μm, and 8 μm). I will present a re-analysis of archival Spitzer/IRAC images of 11 young, low-mass (44 MJup-0.88 MSun; K3.5-M7.5) stars in 3 nearby star-forming regions (Chameleon, Taurus, and Upper Scorpius; d ~ 150 pc; τ ~ 1–10 Myr) known to host faint companions over a range of projected separations (1.7”-7.3”). I will discuss the characteristics of the systems found to have low-mass companions with non-zero [3.6] − [8.0] colors, including the confirmation of a ρ = 4.66” (540 AU), M = 20 MJup companion to [SCH06] J0359+2009, a young brown dwarf in Taurus. My survey is sensitive to companions with masses approaching that of Jupiter at orbital radii of a few hundred AU, discovering wide PMCs in their birth environments and revealing their circum(sub)stellar disks. I will present my newest results in measuring the mid-IR photometry of substellar companions that have been directly imaged at optical or near-IR wavelengths and an automated companion search of all known young stars with existing Spitzer/IRAC data, concluding with my ongoing follow-up observations of candidate wide PMC systems with ground-based telescopes and the outlook for future observations with space-based telescopes.

El olvido del carácter lingüístico de los textos literarios y la opacidad respecto a los orígenes de la experiencia literaria amenazan con sumir en un cierto marasmo a los estudios literarios. El presente artículo plantea la posibilidad de superar esta crisis asumiendo una posición nacida de la reflexión radical sobre los orígenes de la experiencia literaria. Tanto las estilísticas de Liberman y Maldavsky como la de Spitzer –aunque partiendo de visiones antropológicas diversas– se fundamentan en el designio de ir hacia la base psíquica de la creación literaria y así consiguen aprovechar la riqueza significativa esencial del carácter lingüístico del texto literario. En este sentido, la imaginación simbólica tradicional y especialmente la metafísica clásica pueden iluminar la cuestión de la fons poetica, del núcleo originario de la creación literaria, brindando, además, un método fructífero de aproximación e interpretación de los textos literarios.

Context. Micro-physical processes on interstellar dust surfaces are tightly connected to dust properties (i.e. dust composition, size, and shape) and play a key role in numerous phenomena in the interstellar medium (ISM). The large disparity in physical conditions (i.e. density and gas temperature) in the ISM triggers an evolution of dust properties. The analysis of how dust evolves with the physical conditions is a stepping stone towards a more thorough understanding of interstellar dust. Aims. We highlight dust evolution in the Horsehead nebula photon-dominated region. Methods. We used Spitzer/IRAC (3.6, 4.5, 5.8 and 8 μm) and Spitzer/MIPS (24 μm) together with Herschel/PACS (70 and 160 μm) and Herschel/SPIRE (250, 350 and 500 μm) to map the spatial distribution of dust in the Horsehead nebula over the entire emission spectral range. We modelled dust emission and scattering using the THEMIS interstellar dust model together with the 3D radiative transfer code SOC. Results. We find that the nano-grain dust-to-gas ratio in the irradiated outer part of the Horsehead is 6–10 times lower than in the diffuse ISM. The minimum size of these grains is 2–2.25 times larger than in the diffuse ISM, and the power-law exponent of their size distribution is 1.1–1.4 times lower than in the diffuse ISM. In the denser part of the Horsehead nebula, it is necessary to use evolved grains (i.e. aggregates, with or without an ice mantle). Conclusions. It is not possible to explain the observations using grains from the diffuse medium. We therefore propose the following scenario to explain our results. In the outer part of the Horsehead nebula, all the nano-grain have not yet had time to re-form completely through photo-fragmentation of aggregates and the smallest of the nano-grain that are sensitive to the radiation field are photo-destroyed. In the inner part of the Horsehead nebula, grains most likely consist of multi-compositional mantled aggregates.

We have modelled the near-infrared to radio images of the Crab Nebula with a Bayesian SED model to simultaneously fit its synchrotron, interstellar and supernova dust emission. We infer an interstellar dust extinction map with an average $A_{\text{V}}$=1.08$\pm$0.38 mag, consistent with a small contribution (, Comment: 33 pages, 17 figures, Manuscript accepted for publication in MNRAS. Accepted on 31/05/2019. Deposited on 31/05/2019

We present Hubble multi-wavelength photometric catalogs, including (up to) 17 filters with the Advanced Camera for Surveys and Wide Field Camera 3 from the ultra-violet to near-infrared for the Hubble Frontier Fields and associated parallels. We have constructed homogeneous photometric catalogs for all six clusters and their parallels. To further expand these data catalogs, we have added ultra-deep K S -band imaging at 2.2 μm from the Very Large Telescope HAWK-I and Keck-I MOSFIRE instruments. We also add post-cryogenic Spitzer imaging at 3.6 and 4.5 μm with the Infrared Array Camera (IRAC), as well as archival IRAC 5.8 and 8.0 μm imaging when available. We introduce the public release of the multi-wavelength (0.2-8 μm) photometric catalogs, and we describe the unique steps applied for the construction of these catalogs. Particular emphasis is given to the source detection band, the contamination of light from the bright cluster galaxies (bCGs), and intra-cluster light (ICL). In addition to the photometric catalogs, we provide catalogs of photometric redshifts and stellar population properties. Furthermore, this includes all the images used in the construction of the catalogs, including the combined models of bCGs and ICL, the residual images, segmentation maps, and more. These catalogs are a robust data set of the Hubble Frontier Fields and will be an important aid in designing future surveys, as well as planning follow-up programs with current and future observatories to answer key questions remaining about first light, reionization, the assembly of galaxies, and many more topics, most notably by identifying high-redshift sources to target.

著者人数: 70名(所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 芝井, 広; 船木, 一幸; 磯部, 直樹; 川田, 光伸; 權, 靜美; 松原, 英雄; 中川, 貴雄; 小川, 博之; 佐藤, 洋一; 篠崎, 慶亮; 杉田, 寛之; 和田, 武彦; 山田, 亨; 山村, 一誠), Number of authors: 70(Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS): Shibai, Hiroshi; Funaki, Ikkoh; Isobe, Naoki; Kawada, Mitsunobu; Kwon, Jungmi; Matsuhara, Hideo; Nakagawa, Takao; Ogawa, Hiroyuki; Sato, Yoichi; Shinozaki, Keisuke; Sugita, Hiroyuki; Wada, Takehiko; Yamada, Toru; Yamamura, Issei), 資料番号: SA1180106000

International audience

Y dwarfs provide a unique opportunity to study free-floating, planetary-mass objects with atmospheric temperatures approaching those of known Jupiter-like exoplanets. Obtaining distances to these objects is an essential step in determining absolute physical parameters such as mass, age, and metallicity. Using Spitzer/IRAC ch2 images taken over baselines of ~2-5 years, we measure precise astrometric fits and distances for 21 late-T and early Y dwarfs. We also present Keck/NIRSPEC spectroscopy for eight new late-T dwarfs and one new Y dwarf discovery. With these data, we expand the sample of known objects that lie within ~20 pc of the Sun, allowing for a deeper understanding of the local field mass function at the coldest temperatures. Furthermore, the updated distances that we measure aid in better understanding the physical parameter space occupied by these ultracool dwarfs. Finally, we find that the Y dwarf class encompasses a large range in absolute magnitude in the near- to mid-infrared photometric bandpasses, indicating a broad range of physical properties, with varying gravities and metallicities.

Cosmological surveys in the far infrared are known to suffer from confusion. The Bayesian de-blending tool, XID+, currently provides one of the best ways to de-confuse deep Herschel SPIRE images, using a flat flux density prior. This work is to demonstrate that existing multi-wavelength data sets can be exploited to improve XID+ by providing an informed prior, resulting in more accurate and precise extracted flux densities. Photometric data for galaxies in the COSMOS field were used to constrain spectral energy distributions (SEDs) using the fitting tool CIGALE. These SEDs were used to create Gaussian prior estimates in the SPIRE bands for XID+. The multi-wavelength photometry and the extracted SPIRE flux densities were run through CIGALE again to allow us to compare the performance of the two priors. Inferred ALMA flux densities (F$^i$), at 870$\mu$m and 1250$\mu$m, from the best fitting SEDs from the second CIGALE run were compared with measured ALMA flux densities (F$^m$) as an independent performance validation. Similar validations were conducted with the SED modelling and fitting tool MAGPHYS and modified black body functions to test for model dependency. We demonstrate a clear improvement in agreement between the flux densities extracted with XID+ and existing data at other wavelengths when using the new informed Gaussian prior over the original uninformed prior. The residuals between F$^m$ and F$^i$ were calculated. For the Gaussian prior, these residuals, expressed as a multiple of the ALMA error ($\sigma$), have a smaller standard deviation, 7.95$\sigma$ for the Gaussian prior compared to 12.21$\sigma$ for the flat prior, reduced mean, 1.83$\sigma$ compared to 3.44$\sigma$, and have reduced skew to positive values, 7.97 compared to 11.50. These results were determined to not be significantly model dependent. This results in statistically more reliable SPIRE flux densities., Comment: 8 pages, 7 figures, 3 tables. Accepted for publication in A&A

We present a model that describes stellar infrared excesses due to heating of the interstellar (IS) dust by a hot star passing through a diffuse IS cloud. This model is applied to six lambda Bootis stars with infrared excesses. Plausible values for the IS medium (ISM) density and relative velocity between the cloud and the star yield fits to the excess emission. This result is consistent with the diffusion/accretion hypothesis that lambda Bootis stars (A- to F-type stars with large underabundances of Fe-peak elements) owe their characteristics to interactions with the ISM. This proposal invokes radiation pressure from the star to repel the IS dust and excavate a paraboloidal dust cavity in the IS cloud, while the metal-poor gas is accreted onto the stellar photosphere. However, the measurements of the infrared excesses can also be fit by planetary debris disk models. A more detailed consideration of the conditions to produce lambda Bootis characteristics indicates that the majority of infrared-excess stars within the Local Bubble probably have debris disks. Nevertheless, more distant stars may often have excesses due to heating of interstellar material such as in our model., 10 pages, 5 figures, 4 tables, accepted by ApJ, emulateapj

As part of a large study to investigate the nature of the longer wavelength continuum emission of radio-loud AGNs, we present new mid- to far-infrared (MFIR) and high-frequency radio observations for a complete sample of 2 Jy powerful southern radio galaxies at intermediate redshifts (0.05

We present here sore of the first results we have obtained oil the study of the optical spectra, of Spitzer/MIPS 24 mu m selected galaxies in the COSMOS field. This is part of a, series of studies we are conducting to analyse the optical spectral properties of mid-infrared (mid-IR) galaxies with different, IR, luminosities tip to high redshifts. The results shown here correspond to the brightest S-24 mu m > 2 mJy IR galaxy population at z