- ID:
- ivo://CDS.VizieR/J/A+A/365/409
- Title:
- ISO continuum observations of quasars
- Short Name:
- J/A+A/365/409
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Eight luminous quasars with -30<M_B_<-27 at z=1.4-3.7 have been observed in the mid- and far-infrared using ISO. All the quasars have been detected in the mid-infrared bands of ISOCAM, while no far-infrared detections have been made with ISOPHOT. SEDs (Spectral Energy Distributions) from the UV to far-infrared have been obtained while supplementing ISO observations with photometry in the optical and near-infrared made from the ground within 17 months. The SEDs are compared with the MED (Mean spectral Energy Distributions) of low-redshift quasars with -27<M_B_<-22. It is shown that our far-infrared observations were limited by confusion noise due to crowded sources.
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- ID:
- ivo://CDS.VizieR/J/AJ/123/2070
- Title:
- ISO deep asteroid search
- Short Name:
- J/AJ/123/2070
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A total of six deep exposures (using the astronomical observation template CAM01 with a 6" pixel field of view) through the ISOCAM LW10 filter (IRAS band 1, i.e., 12{mu}m) were obtained on a ~15' square field centered on the ecliptic plane. Point sources were extracted using the technique described in 1999 by Deert et al. Twoknown asteroids appear in these frames, and 20 sources moving with velocities appropriate for main-belt asteroids are present. Most of the asteroids detected have flux densities less than 1 mJy, that is, between 150 and 350 times fainter than any of the asteroids observed by IRAS. These data provide the first direct measurement of the 12{mu}m sky-plane density for asteroids on the ecliptic equator. The median zodiacal foreground, as measured by ISOCAM during this survey, is found to be 22.1+/-1.5mJy/pixel, i.e. 26.2+/-1.7MJy/sr. The results presented here imply that the actual number of kilometer-sized asteroids may be higher than several recent estimates based upon observations at visual wavelengths and are in reasonable agreement with the statistical asteroid model. Using results from the observations presented here, together with three other recent population estimates, we conclude that the cumulative number of main-belt asteroids with diameters greater than 1km is (1.2+/-0.5)x10^6^.
- ID:
- ivo://CDS.VizieR/J/A+A/403/141
- Title:
- ISOGAL sources in intermediate bulge fields
- Short Name:
- J/A+A/403/141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of ISOGAL sources in the "intermediate" galactic bulge (|l|<2{deg}, |b|~1{deg}-4{deg}), observed by ISOCAM at 7 and 15{mu}m. In combination with near-infrared (I, J, Ks) data of DENIS survey, complemented by 2MASS data, we discuss the nature of the ISOGAL sources, their luminosities, the interstellar extinction and the mass-loss rates. A large fraction of the 1464 detected sources at 15{mu}m are AGB stars above the RGB tip, a number of them show an excess in ([7]-[15])_0_ and (Ks-[15])_0_ colours, characteristic of mass-loss. The latter, especially (Ks-[15])_0_, provide estimates of the mass-loss rates and show their distribution in the range 10^-8^ to 10^-5^M_{sun}_/yr.
- ID:
- ivo://CDS.VizieR/J/A+A/342/313
- Title:
- ISO HDF observations from PRETI method
- Short Name:
- J/A+A/342/313
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have developed a new ISOCAM data reduction technique based on wavelet analysis, especially designed for the detection of faint sources in mid-infrared surveys. This method, the Pattern REcognition Technique for Isocam data (PRETI) has been used to reduce the observations of the Hubble Deep Field (HDF) and flanking fields with ISOCAM at 6.75 (LW2) and 15{mu}m (LW3) (Rowan-Robinson et al. 1997MNRAS.289..490R). Simulations of ISOCAM data allow us to test the photometric accuracy and completeness of the reduction. According to these simulations, the PRETI source list is 95% complete in the 15{mu}m band at 200{mu}Jy and in the 6.75{mu}m band at 65{mu}Jy, using detection thresholds which minimize the number of false detections. We detect 49 objects in the ISO-HDF at high confidence secure level, 42 in the LW3 filter, 3 in the LW2 filter, and 4 in both filters. An additional, less secure, list of 100 sources is presented, of which 89 are detected at 15{mu}m only, 7 at 6.75{mu}m only and 4 in both filters. All ISO-HDF objects detected in the HDF itself have optical or infrared counterparts, except for one from the additional list. All except one of the radio sources detected in the field by Fomalont et al. (1997ApJ...475L...5F) are detected with ISOCAM. Using a precise correction for the field of view distortion of ISOCAM allows us to separate blended sources. This, together with the fact that PRETI allows to correct data on the tail of cosmic rays glitches, lead us to produce deeper source lists than previous authors. Our list of bright sources agree with those of Desert et al. (1999A&A...342..363D) in both filters, and with those of Goldschmidt et al. (1997MNRAS.289..465G) in the LW3 filter, with systematic difference in photometry. ISO is an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, The Netherlands and the United Kingdom) and with participation of ISAS and NASA.
565. ISO Observation Log
- ID:
- ivo://CDS.VizieR/VI/111
- Title:
- ISO Observation Log
- Short Name:
- VI/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Infrared Space Observatory (ISO) is an ESA (European Space Agency) project with instruments funded by ESA member states (especially the PI countries France, Germany, The Netherlands and the United Kingdom) and with participation of ISAS (Japan) and NASA (USA). It was operated from November 1995 till May 1998, almost a year longer than expected. As an unprecedented observatory for infrared astronomy, able to examine cool and hidden places in the Universe, ISO successfully made nearly 30,000 scientific observations. The ISO Data Archive is available at the ISO Data Centre at https://www.cosmos.esa.int/web/iso it includes about 150,000 observations, if account is taken of calibration and parallel or serendipity mode observations. The catalogue contains all observations performed in standard observing modes exempt from technical problems; special flags indicate calibration observations. ISO helpdesk: https://support.cosmos.esa.int/iso/
- ID:
- ivo://CDS.VizieR/J/A+A/466/1205
- Title:
- ISOPHOT 170{mu}m Serendipity Survey. IV
- Short Name:
- J/A+A/466/1205
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 170 micron far-infrared slew data of the ISOPHOT Serendipity Survey (ISOSS) has been assembled to a sky atlas with ~15% sky coverage. The redundant information of the brightnesss at slew crossings has been used to globally rescale and homogenize the slew brightnesses, leading to significantly increased photometric accuracy and reproducibility as well as the homogeneity of the maps. The corrected slew data were remapped with a constant grid size of 22.4arcsec onto 124 maps in galactic coordinates.
- ID:
- ivo://CDS.VizieR/J/A+A/474/883
- Title:
- ISOSS J23053+5953 maps
- Short Name:
- J/A+A/474/883
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Due to the short timescales involved and observational difficulties, our knowledge of the earliest phases of massive star formation remains incomplete. We aim to explore the physical conditions during the initial phases of high-mass star formation and to detect a genuine massive (mass M>8M_{sun}_) protostar at an early evolutionary stage.
- ID:
- ivo://CDS.VizieR/J/A+A/227/82
- Title:
- JHKLM photometry of 'IRAS-discovered' stars
- Short Name:
- J/A+A/227/82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents results of JHKLM photometry data analysis of 249 southern 'IRAS-discovered' stars, which exhibit an emission feature at 11.3 microns in their low-resolution spectra (class 4n stars). The method of Epchtein et al. (1987A&AS...71...39E) is used to separate oxygen-rich and carbon-rich stars on the basis of their sole NIR and IRAS broad-band fluxes. It is shown that NIR data are necessary to calculate the total IR energy received from IRAS stars and such fundamental parameters as individual mass loss rates. An evolutionary model is developed to match the sequence of stars in color diagrams. It is suggested that the sequence of increasing optical depths might not be an evolutionary sequence, but would rather reflect the termination of a process in which the near-IR index increases very quickly at the beginning and is strongly dependent on the mass loss rate.
- ID:
- ivo://CDS.VizieR/J/A+A/458/533
- Title:
- JHKL' photometry of selected AGB stars
- Short Name:
- J/A+A/458/533
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a near-infrared monitoring programme of a selected sample of stars, initially suspected to be Mira variables and OH/IR stars, covering more than a decade of observations. The objects monitored cover the typical range of IRAS colours shown by O-rich stars on the asymptotic giant branch and show a surprisingly large diversity of variability properties. Sixteen objects are confirmed as large-amplitude variables.
- ID:
- ivo://CDS.VizieR/J/A+A/394/225
- Title:
- JHK photometry around RAFGL 7009S
- Short Name:
- J/A+A/394/225
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- RAFGL7009S is a deeply embedded massive young stellar objet (YSO) showing strong ice and saturated silicate absorption features in the mid infrared. It is associated with the ultracompact H II region G25.65+1.05, which may be excited by a B1V star. We have obtained JHK images of a 1' field centred on this YSO. In K we detect a non-resolved object coinciding with the radio continuum emission peak. Considering the high extinction towards this source (A_V_>=100mag), the observed K emission is more than 7~mag in excess of that expected for a B1V star. We suggest that this emission is mainly due to scattering of the central zone emission, as recently found for a sample of embedded massive YSOs associated with 3.1{mu}m H_2_O ice absorption (Ishii et al., 2002AJ....124..430I). We estimate the YSO's age to be 2x10^4^ years. The outflow, the methanol maser emission and the strong ice absorption features suggest the presence of a dense medium very close to the star, possibly a disk. The observations were obtained with the Montreal Near-IR Camera (MONICA, Nadeau et al., 1994PASP..106..909N) mounted at the F/8 Cassegrain focus of the 3.6-m Canada-France-Hawaii Telescope on 1996 July 1 UT. Frames were obtained through the J, H and K broad-band filters with total integration times of 840s, 160s and 100s Details about the instrumentation, the calibration and the data analysis can be found in Deharveng et al. (1999, Cat. <J/A+A/344/943>).
