- ID:
- ivo://CDS.VizieR/J/AJ/143/87
- Title:
- IRAC photometry of massive M31 globular clusters
- Short Name:
- J/AJ/143/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Several population synthesis models now predict integrated colors of simple stellar populations in the mid-infrared bands. To date, the models have not been extensively tested in this wavelength range. In a comparison of the predictions of several recent population synthesis models, the integrated colors are found to cover approximately the same range but to disagree in detail, for example, on the effects of metallicity. To test against observational data, globular clusters (GCs) are used as the closest objects to idealized groups of stars with a single age and single metallicity. Using recent mass estimates, we have compiled a sample of massive, old GCs in M31 which contain enough stars to guard against the stochastic effects of small-number statistics, and measured their integrated colors in the Spitzer/IRAC bands. Comparison of the cluster photometry in the IRAC bands with the model predictions shows that the models reproduce the cluster colors reasonably well, except for a small (not statistically significant) offset in [4.5]-[5.8]. In this color, models without circumstellar dust emission predict bluer values than are observed. Model predictions of colors formed from the V band and the IRAC 3.6 and 4.5{micro}m bands are redder than the observed data at high metallicities and we discuss several possible explanations. In agreement with model predictions, V-[3.6] and V-[4.5] colors are found to have metallicity sensitivity similar to or slightly better than V-K_s_.
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- ID:
- ivo://CDS.VizieR/J/ApJ/719/9
- Title:
- IRAC point-source catalog of Vela-D cloud
- Short Name:
- J/ApJ/719/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the observations of Cloud D in the Vela Molecular Ridge, obtained with the Infrared Array Camera (IRAC) camera on board the Spitzer Space Telescope at the wavelengths {lambda}=3.6, 4.5, 5.8, and 8.0um. A photometric catalog of point sources, covering a field of approximately 1.2deg^2^, has been extracted and complemented with additional available observational data in the millimeter region. Previous observations of the same region, obtained with the Spitzer MIPS camera in the photometric bands at 24um and 70um, have also been reconsidered to allow an estimate of the spectral slope of the sources in a wider spectral range. A total of 170299 point sources, detected at the 5{sigma} sensitivity level in at least one of the IRAC bands, have been reported in the catalog. There were 8796 sources for which good quality photometry was obtained in all four IRAC bands. For this sample, a preliminary characterization of the young stellar population based on the determination of spectral slope is discussed; combining this with diagnostics in the color-magnitude and color-color diagrams, the relative population of young stellar objects (YSOs) in different evolutionary classes has been estimated and a total of 637 candidate YSOs have been selected.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/1584
- Title:
- IRAC point sources for M32
- Short Name:
- J/MNRAS/446/1584
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the population of cool, evolved stars in the Local Group dwarf elliptical galaxy M32, using Infrared Array Camera observations from the Spitzer Space Telescope. We construct deep mid-infrared colour-magnitude diagrams for the resolved stellar populations within 3.5 arcmin of M32's centre, and identify those stars that exhibit infrared excess. Our data are dominated by a population of luminous, dust-producing stars on the asymptotic giant branch (AGB) and extend to approximately 3 mag below the AGB tip. We detect for the first time a sizeable population of `extreme' AGB stars, highly enshrouded by circumstellar dust and likely completely obscured at optical wavelengths. The total dust-injection rate from the extreme AGB candidates is measured to be 7.5x10^-7^M_{sun}_/yr, corresponding to a gas mass-loss rate of 1.5x10^-4^M_{sun}_/yr. These extreme stars may be indicative of an extended star formation epoch between 0.2 and 5Gyr ago.
- ID:
- ivo://CDS.VizieR/J/A+A/632/A19
- Title:
- IRAM intensity maps of 3 low-mass protostars
- Short Name:
- J/A+A/632/A19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Methanol is a key species in astrochemistry since it is the most abundant organic molecule in the interstellar medium and is thought to be the mother molecule of many complex organic species. Estimating the deuteration of methanol around young protostars is of crucial importance because it highly depends on its formation mechanisms and the physical conditions during its moment of formation. We analyse several dozens of transitions from deuterated methanol isotopologues coming from various existing observational datasets obtained with the IRAM-PdBI and ALMA sub-mm interferometers to estimate the methanol deuteration surrounding three low-mass protostars on Solar System scales. A population diagram analysis allows us to derive a [CH_2_DOH]/[CH_3_OH] abundance ratio of 3-6% and a [CH_3_OD]/[CH_3_OH] ratio of 0.4-1.6% in the warm inner (<100-200AU) protostellar regions. These values are typically ten times lower than those derived with previous single-dish observations towards these sources but they are one to two orders of magnitude higher than the methanol deuteration measured in massive hot cores. Dust temperature maps obtained from Herschel and Planck observations show that massive hot cores are located in warmer molecular clouds than low-mass sources, with temperature differences of about 10K. The comparison of our measured values with the predictions of the gas-grain astrochemical model GRAINOBLE shows that such a temperature difference is sufficient to explain the different deuteration observed in low- to high-mass sources. This suggests that the physical conditions of the molecular cloud at the origin of the protostars mostly govern the present observed deuteration of methanol and, therefore, of more complex organic molecules. Finally, the methanol deuteration measured towards young solar-type protostars on Solar System scales seems to be higher by a factor of about 5 than the upper limit in methanol deuteration estimated in comet Hale-Bopp. If this result is confirmed by subsequent observations of other comets, this would imply that an important reprocessing of the organic material likely occurred in the solar nebula during the formation of the Solar System.
- ID:
- ivo://CDS.VizieR/J/A+A/560/A24
- Title:
- IRAM 30m CO-observations in W43
- Short Name:
- J/A+A/560/A24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed molecular clouds in the giant star forming region W43. For this project we used the IRAM 30m telescope to observe the molecular emission lines ^13^CO (2-1) and C^18^O (2-1), that trace the mid-density (n~10^3^cm^-3^) molecular gas. The lines were observed with the HERA receiver and the VESPA backend. At the observed frequencies the IRAM 30m has a beam size of 11.7". We include two FITS files containing the data-cubes (pos-pos-vel) of the ^13^CO and C^18^O emission lines of the W43 complex. We used equatorial coordinates for the spatial dimensions and v_lsr_ for the spectral dimension. The pixel size is 5.9" in spatial dimension and the spectral resolution is 0.16km/s. All values are in K. The data-cubes span an area of about 1x1.5{deg} (RAxDec) around the center of the maps at 18:46:54.4 -02:14:11 (EQ=J2000) and the velocity range from 30 to 130km/s and include the complete W43 complex and several fore- and background clouds.
- ID:
- ivo://CDS.VizieR/J/A+A/563/A97
- Title:
- IRAM 30m reduced spectra of 59 sources
- Short Name:
- J/A+A/563/A97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Understanding the chemical evolution of young (high-mass) star-forming regions is a central topic in star formation research. Chemistry is employed as a unique tool 1) to investigate the underlying physical processes and 2) to characterize the evolution of the chemical composition. With these aims in mind, we observed a sample of 59 high-mass star-forming regions at different evolutionary stages varying from the early starless phase of infrared dark clouds to high-mass protostellar objects to hot molecular cores and, finally, ultra-compact HII regions at 1mm and 3mm with the IRAM 30m telescope. We determined their large-scale chemical abundances and found that the chemical composition evolves along with the evolutionary stages.
- ID:
- ivo://nasa.heasarc/iram30mlog
- Title:
- IRAM 30-m Single-Dish Telescope Observation Log
- Short Name:
- IRAM30MLOG
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the IRAM 30-m single-dish telescope observation log. The Institut de Radio Astronomie Millimetrique (IRAM) was founded in 1979 and is operated as a French-German-Spanish collaboration. Its partner institutes are the CNRS (Centre National de la Recherche Scientifique, France), the MPG (Max Planck Gesellschaft, Germany), and the IGN (Instituto Geografico Nacional, Spain). The principal activity of IRAM is the study of cold matter (molecular gas and dust) in the solar system, in our Galaxy, and out to cosmological distances, in order to determine its composition, density, mass, temperature, and kinematics. IRAM operates two observatories at millimeter wavelengths which are open to the international astronomical community: the 30-m single-dish telescope on Pico Veleta (2850 m), Spain, and the six-antenna interferometer on the Plateau de Bure (2550 m) in France. Both sites are at high altitude to reduce the absorption by water vapor. The observatories are supported by the IRAM offices and laboratories in Granada and Grenoble. The observation log included here concerns the 30-m single-dish telescope, and summarizes the observations made there since September 30, 2009. The observation log for the the six-antenna interferometer on the Plateau de Bure in France is also available as the HEASARC database table <a href="/W3Browse/ground-based/irampdblog.html">IRAMPDBLOG</a>, and the observation log for NOEMA (the NOrthern Extended Millimeter Array), the successor to the Plateau de Bure observatory, is available as the HEASARC database table <a href="/W3Browse/ground-based/iramnoelog.html">IRAMNOELOG</a>. For more information on IRAM, see <a href="http://www.iram-institute.org/">the IRAM home page</a>. This table was originally ingested by the HEASARC in January 2011. It is based on the CDS table B/iram/, files 30m.dat and 30m_pi.dat. It was last updated in September 2020, based on an updated version of these tables which were also obtained from the CDS. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/iramnoelog
- Title:
- IRAM NOEMA (NOrthern Extended Millimeter Array) Observation Log
- Short Name:
- IRAMNOELOG
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the IRAM NOEMA (NOrthern Extended Millimeter Array) observation log. The Institut de Radio Astronomie Millimetrique (IRAM) was founded in 1979 and is operated as a French-German-Spanish collaboration. Its partner institutes are the CNRS (Centre National de la Recherche Scientifique, France), the MPG (Max Planck Gesellschaft, Germany), and the IGN (Instituto Geografico Nacional, Spain). The principal activity of IRAM is the study of cold matter (molecular gas and dust) in the solar system, in our Galaxy, and out to cosmological distances, in order to determine its composition, density, mass, temperature, and kinematics. IRAM operates two observatories at millimeter wavelengths which are open to the international astronomical community: the 30-m single-dish telescope on Pico Veleta (2850 m), Spain, and the six-antenna interferometer on the Plateau de Bure (2550 m) in France. Both sites are at high altitude to reduce the absorption by water vapor. The observatories are supported by the IRAM offices and laboratories in Granada and Grenoble. The observation log included here concerns NOEMA, the NOrthern Extended Millimeter Array, and summarizes the observations made there. NOEMA is the successor to the Plateau de Bure observatory. During its history, the observatory at the Plateau de Bure underwent several track extensions, received additional antennas (all of 15-m diameter and of similar construction to the first ones) and technical upgrades. From a three-antenna interferometer with a maximum baseline of 288 meters in 1988, it has evolved to a eight-antenna array with baselines up to 760 meters in 2016. With the inauguration of the seventh antenna in September, 2014, the observatory started its transformation into NOEMA. More information about NOEMA is <a href="http://www.iram.fr/IRAMFR/GILDAS/doc/html/noema-intro-html/noema-intro.html">available at the IRAM web site</a>. The observation log for the 30-m telescope is available as the HEASARC database table <a href="/W3Browse/ground-based/iram30mlog.html">IRAM30MLOG</a>, and the observation log for the Plateau de Bure Interferometer is available as the HEASARC database table <a href="/W3Browse/ground-based/irampdblog.html">IRAMPDBLOG</a>. For more information on IRAM, see <a href="http://www.iram-institute.org/">the IRAM home page</a>. This table was originally ingested by the HEASARC in August 2017. It is based on the CDS table B/iram/, files noema.dat and noema_pi.dat. It was last updated in September 2020, based on an updated version of these tables which were also obtained from the CDS. This is a service provided by NASA HEASARC .
7039. IRAM Observation Logs
- ID:
- ivo://CDS.VizieR/B/iram
- Title:
- IRAM Observation Logs
- Short Name:
- B/iram
- Date:
- 04 Jan 2022 15:31:49
- Publisher:
- CDS
- Description:
- The Institut de Radio Astronomie Millimetrique (IRAM) was founded in 1979 and is operated as a French-German-Spanish collaboration. Its partner institutes are the CNRS (Centre National de la Recherche Scientifique, France), the MPG (Max Planck Gesellschaft, Germany), and the IGN (Instituto Geografico Nacional, Spain). The principal activity of IRAM is the study of cold matter (molecular gas and dust) in the solar system, in our Galaxy, and out to cosmological distances in order to determine its composition, density, mass, temperature, and kinematics. IRAM operates two observatories at millimeter wavelengths which are open to the international astronomical community: The 30-m single-dish telescope on Pico Veleta (2850m), Spain, and the six-antenna interferometer on the Plateau de Bure (2550m) in France. Both sites are at high altitude to reduce the absorption by water vapor. The observatories are supported by the IRAM offices and laboratories in Granada and Grenoble. The observation log included here concerns the Plateau de Bure site, and summarizes the observations made there from December 1990. The observations log of the 30-m single-dish telescope covers a period starting in January 2009. This log was produced using a header archive, a collaborative effort between IRAM and IAA/CSIC. NOEMA (NOrthern Extended Millimeter Array) is the successor to the Plateau du Bure observatory. During its history, the observatory at the Plateau de Bure underwent several track extensions, received additional antennas (all of 15m diameter and similar construction as the first ones) and technical upgrades. From a three antenna interferometer with a maximum baseline of 288 meters in 1988, it has evolved to a eight-antenna array with baselines up to 760 meters in 2016. With the inauguration of the seventh antenna in September 2014, the observatory has started its transformation into NOEMA.
- ID:
- ivo://CDS.VizieR/VIII/66
- Title:
- IRAM observations in pre-star forming regions
- Short Name:
- VIII/66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The goal of the IRAM key-project ``Small-scale structure of pre-star forming regions'' is to map three nearby (d~150pc), quiescent molecular clouds with a high angular and spectral resolution to study the molecular cloud structure down to the smallest linear scales currently accessible by single dish radio telescopes. The key-project maps are available as data cubes (velocity, right ascension or galactic longitude, declination or galactic latitude) available as a set of 40 FITS files stored in the fits subdirectory; a summary of these 40 files is contained in the file "list.dat". The observations reported concern the molecular clouds L1512, L134A, and MCLD 123.5+24.9 in the Polaris Flare. The released data set of the IRAM key-project (Falgarone et al., 1998A&A...331..669F) are error beam corrected using the beam pattern parameters published by Garcia-Burillo, Guelin and Cernicharo (1993A&A...274..123G) and observations made with the KOSMA 3m telescope. Bensch et al. (2001A&A...365..275B) present the corrected maps using the 30m beam pattern recently published by Greve et al. (1998A&AS..133..271G). They estimate the accuracy of the maps of the key-project as 10-15% for the CO(2-1), except for two ^13^CO(2-1) maps of the MCLD 123.5+24.9/Polaris Flare and of L1512 where the uncertainties are estimated to 22% and 18% respectively. For the CO(1-0) data, the overall accuracy is 11%.