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- ID:
- ivo://CDS.VizieR/J/AJ/138/478
- Title:
- AR Boo differential BVR photometry
- Short Name:
- J/AJ/138/478
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New CCD photometric observations of the eclipsing system AR Boo were obtained from 2006 February to 2008 April. The star's photometric properties are derived from detailed studies of the period variability and of all available light curves.
- ID:
- ivo://CDS.VizieR/J/A+A/368/845
- Title:
- Arcetri Catalog of H2O maser sources. Update.
- Short Name:
- J/A+A/368/845
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a second update of the Arcetri Catalog of water masers (Comoretto et al., 1990A&AS...84..179C; Brand et al., 1994, Cat. <J/A+AS/103/541>). The present study reports the results of the observations carried out with the Medicina 32-m radiotelescope from January 1993 to April 2000 on a sample of 300 sources. This compilation consists of newly discovered maser sources that did not appear in the previous Arcetri Catalogs and is made of: a) detections from the literature, and b) unpublished detections obtained with the Medicina antenna. Overall, 83 out of 300 sources were detected. The detection rate is low (28%) and we attribute this result to the inclusion in our survey of a rather large number of spurious maser detections that have appeared in one particular paper. The observational parameters are reported in tabular form for all the 300 sources and the spectra of the detected masers are presented. We discuss the global properties of the complete Arcetri Catalog based on Comoretto et al. (1990A&AS...84..179C), Brand et al. (1994, Cat. <J/A+AS/103/541>) and the present observations, which now contains 1013 galactic water maser sources. Of these, 937 have an IRAS counterpart within 1 arcmin from the nominal position of the maser. We establish a classification scheme based on the IRAS flux densities which allows to distinguish between water masers associated with star forming regions and late-type stars. The Arcetri Catalog represents a useful data base for systematic studies of galactic water maser sources.
- ID:
- ivo://CDS.VizieR/J/A+AS/103/541
- Title:
- Arcetri Catalogue of H2O Maser Sources
- Short Name:
- J/A+AS/103/541
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An update is presented of the Arcetri Atlas of water masers (Comoretto et al. 1990A&AS...84..179C). It contains the results of observations of water masers with the Medicina 32-m antenna. The observed sources were all discovered in the period 1989-1993, and were found either directly in the course of our own programs or were taken from the literature in which case they were re-observed at Medicina. We give the observed parameters of 214 sources in tabular form, and present all the spectra of the 141 detections.
- ID:
- ivo://nasa.heasarc/arcquincxo
- Title:
- Arches and Quintuplet Clusters Chandra X-Ray Point Source Catalog
- Short Name:
- ARCQUINCXO
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Galactic centre (GC) provides a unique laboratory for a detailed examination of the interplay between massive star formation and the nuclear environment of our Galaxy. Here are presented some of the results from a 100-ks Chandra Advanced CCD Imaging Spectrometer (ACIS) observation of the Arches and Quintuplet star clusters in the form of a catalog of 244 point-like X-ray sources detected in the observation. The deep Chandra ACIS-I observation (Obs. ID: 4500) was carried out on 2004 June 9. The Arches cluster was placed about 1-arcmin away from the aim point to minimize the effect of the CCD gaps on mapping the extended X-ray emission around the cluster. This table was created by the HEASARC in July 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/371/38">CDS Catalog J/MNRAS/371/38</a> file table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/A+A/556/A26
- Title:
- Arches cluster: IR phot., extinction and masses
- Short Name:
- J/A+A/556/A26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Galactic Center is the most active site of star formation in the Milky Way Galaxy, where particularly high-mass stars have formed very recently and are still forming today. However, since we are looking at the Galactic Center through the Galactic disk, knowledge of extinction is crucial to study this region. The Arches cluster is a young, massive starburst cluster near the Galactic Center. We observed the Arches cluster out to its tidal radius using Ks-band imaging obtained with NAOS/CONICA at the VLT combined with Subaro/Cisco J-band data to gain a full understanding of the cluster mass distribution. We show that the determination of the mass of the most massive star in the Arches cluster, which had been used in previous studies to establish an upper-mass limit for the star formation process in the Milky Way, strongly depends on the assumed slope of the extinction law. Assuming the two regimes of widely used infrared extinction laws, we show that the difference can reach up to 30% for individually derived stellar masses and {Delta}AKs~1 magnitude in acquired Ks-band extinction, while the present mass function slope changes by ~0.17dex. The present-day mass function slope derived assuming the Nishiyama et al. (2009) extinction law increases from a flat slope of {alpha}-Nishi=-1.50+/-0.35 in the core (r<0.2pc) to {alpha}-Nishi=-2.21+/-0.27 in the intermediate annulus (0.2<r<0.4pc), where the Salpeter slope is -2.3. The present-day mass function steepens to {alpha}-Nishi=-3.21+/-0.30 in the outer annulus (0.4<r<1.5pc), indicating that the outer cluster region is depleted of high mass stars. This picture is consistent with mass segregation due to the dynamical evolution of the cluster.
- ID:
- ivo://CDS.VizieR/J/A+A/647/A110
- Title:
- Arches cluster JVLA 6 and 10GHz images
- Short Name:
- J/A+A/647/A110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high angular resolution radio observations of the Arches cluster in the Galactic centre, one of the most massive young clusters in the Milky Way. The data were acquired in two epochs and at 6 and 10 GHz with the Karl G. Jansky Very Large Array (JVLA). The rms noise reached is 3-4 times better than previous observations and we have almost doubled the number of known radio stars in the cluster. Nine of them have spectral indices consistent with thermal emission from ionised stellar winds. One is a confirmed wind colliding binary and two sources are ambiguous cases. Regarding variability, the radio emission appears to be stable on time scales of a few to ten years. Finally, we have showed that the number of radio stars can be used as a tool for constraining the age or mass of a cluster and also its mass function.
- ID:
- ivo://CDS.VizieR/J/MNRAS/410/1837
- Title:
- Architecture of A1386 and the Sloan Great Wall
- Short Name:
- J/MNRAS/410/1837
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new radial velocities from AAOmega on the Anglo-Australian Telescope for 307 galaxies (bJ < 19.5) in the region of the rich cluster Abell 1386. Consistent with other studies of galaxy clusters that constitute subunits of superstructures, we find that the velocity distribution of A1386 is very broad (21000-42000 km/s, or z = 0.08-0.14) and complex. The mean redshift of the cluster that Abell designated as number 1386 is found to be ~0.104. However, we find that it consists of various superpositions of line-of-sight components. We investigate the reality of each component by testing for substructure and searching for giant elliptical galaxies in each and show that A1386 is made up of at least four significant clusters or groups along the line of sight whose global parameters we detail. Peculiar velocities of brightest galaxies for each of the groups are computed and found to be different from previous works, largely due to the complexity of the sky area and the depth of analysis performed in the present work. We also analyse A1386 in the context of its parent superclusters: Leo A and especially the Sloan Great Wall. Although the new clusters may be moving towards mass concentrations in the Sloan Great Wall or beyond, many are most likely not yet physically bound to it.
- ID:
- ivo://CDS.VizieR/J/ApJ/898/119
- Title:
- Archival Keck HIRES spectra analyzed with The Cannon
- Short Name:
- J/ApJ/898/119
- Date:
- 15 Dec 2021 00:08:08
- Publisher:
- CDS
- Description:
- To accurately interpret the observed properties of exoplanets, it is necessary to first obtain a detailed understanding of host star properties. However, physical models that analyze stellar properties on a per-star basis can become computationally intractable for sufficiently large samples. Furthermore, these models are limited by the wavelength coverage of available spectra. We combine previously derived spectral properties from the Spectroscopic Properties of Cool Stars (SPOCS) catalog with generative modeling using The Cannon to produce a model capable of deriving stellar parameters (logg, Teff, and vsini) and 15 elemental abundances (C, N, O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Ni, and Y) for stellar spectra observed with Keck Observatory's High Resolution Echelle Spectrometer (HIRES). We demonstrate the high accuracy and precision of our model, which takes just ~3s to classify each star, through cross-validation with pre-labeled spectra from the SPOCS sample. Our trained model, which takes continuum-normalized template spectra as its inputs, is publicly available at http://github.com/malenarice/keckspec. Finally, we interpolate our spectra and employ the same modeling scheme to recover labels for 477 stars using archival stellar spectra obtained prior to Keck's 2004 detector upgrade, demonstrating that our interpolated model can successfully predict stellar labels for different spectrographs that have (1) sufficiently similar systematics and (2) a wavelength range that substantially overlaps with that of the post-2004 HIRES spectra.
- ID:
- ivo://fai.kz/spectra_agn_archive/q/ssa
- Title:
- Archive of AGN spectral observations
- Short Name:
- AGN Arch. SSAP
- Date:
- 06 Mar 2025 07:24:23
- Publisher:
- Fesenkov Astrophysical Institute
- Description:
- The archive of AGN spectral observations is obtained on AZT-8 telescope at the Fesenkov Astrophysical Institute (FAI), Almaty, Kazakhstan. It represents the result of observations for abot 25 years - from 1970 to 1995. All observations were carried out at AZT-8 (D = 700 mm, F[main] = 2800 mm, F[Cassegrain] = 11000 mm) with a high-power spectrograph. In 1967-68, on the basis of the image intensifier (https://doi.org/10.1080/1055679031000084795a) developed and assembled the spectrograph of the original design in the workshops of the FAI.
