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5321. Properties of nearby clusters of galaxies. IV.
ID:
ivo://CDS.VizieR/J/A+AS/146/373
Title:
Properties of nearby clusters of galaxies. IV.
Short Name:
J/A+AS/146/373
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper is the fourth of a series (Trevese et al. 1992, Paper I, Cat. <J/A+AS/94/327>, Flin et al. 1995, Cat. <J/A+AS/110/313>, Paper II, Trevese et al. 1997, Cat. <J/A+AS/125/459>, Paper III) presenting F band photometry, from digitized 48-inch Palomar plates, of the galaxies brighter than m_3+3 10 clusters of galaxies. For each galaxy, equatorial coordinates, magnitude, size, ellipticity and orientation are given. We provide finding charts and contour maps of the galaxy surface density for each cluster.
5322. Properties of N2K stars & new gas giant companions
ID:
ivo://CDS.VizieR/J/AJ/156/213
Title:
Properties of N2K stars & new gas giant companions
Short Name:
J/AJ/156/213
Date:
21 Oct 2021
Publisher:
CDS
Description:
The N2K planet search program was designed to exploit the planet-metallicity correlation by searching for gas giant planets orbiting metal-rich stars. Here, we present the radial velocity measurements for 378 N2K target stars that were observed with the HIRES spectrograph at Keck Observatory between 2004 and 2017. With this data set, we announce the discovery of six new gas giant exoplanets: a double-planet system orbiting HD 148164 (Msini of 1.23 and 5.16 M_JUP_) and single planet detections around HD 55696 (Msini=3.87 M_JUP_), HD 98736 (Msini=2.33 M_JUP_), HD 203473 (Msini=7.8 M_JUP_), and HD 211810 (Msini=0.67 M_JUP_). These gas giant companions have orbital semimajor axes between 1.0 and 6.2 au and eccentricities ranging from 0.13 to 0.71. We also report evidence for three gravitationally bound companions with Msini between 20 and 30 M_JUP_, placing them in the mass range of brown dwarfs, around HD 148284, HD 214823, and HD 217850, and four low-mass stellar companions orbiting HD 3404, HD 24505, HD 98630, and HD 103459. In addition, we present updated orbital parameters for 42 previously announced planets. We also report a nondetection of the putative companion HD 73256 b. Finally, we highlight the most promising candidates for direct imaging and astrometric detection, and we find that many hot Jupiters from our sample could be detectable by state-of-the-art telescopes such as Gaia.
5323. Properties of PMS stars in young cluster Berkeley 59
ID:
ivo://CDS.VizieR/J/AJ/155/44
Title:
Properties of PMS stars in young cluster Berkeley 59
Short Name:
J/AJ/155/44
Date:
21 Oct 2021
Publisher:
CDS
Description:
Berkeley 59 is a nearby (~1 kpc) young cluster associated with the Sh2-171 H II region. We present deep optical observations of the central ~2.5x2.5 pc^2^ area of the cluster, obtained with the 3.58 m Telescopio Nazionale Galileo. The V/(V-I) color-magnitude diagram manifests a clear pre-main-sequence (PMS) population down to ~0.2 M_{sun}_. Using the near-infrared and optical colors of the low-mass PMS members, we derive a global extinction of A_V_=4 mag and a mean age of ~1.8 Myr, respectively, for the cluster. We constructed the initial mass function and found that its global slopes in the mass ranges of 0.2-28 M_{sun}_ and 0.2-1.5 M_{sun}_ are -1.33 and -1.23, respectively, in good agreement with the Salpeter value in the solar neighborhood. We looked for the radial variation of the mass function and found that the slope is flatter in the inner region than in the outer region, indicating mass segregation. The dynamical status of the cluster suggests that the mass segregation is likely primordial. The age distribution of the PMS sources reveals that the younger sources appear to concentrate close to the inner region compared to the outer region of the cluster, a phenomenon possibly linked to the time evolution of star-forming clouds. Within the observed area, we derive a total mass of ~10^3^ M_{sun}_ for the cluster. Comparing the properties of Berkeley 59 with other young clusters, we suggest it resembles more closely the Trapezium cluster.
5324. Properties of 70 RR Lyrae stars in the LMC bar
ID:
ivo://CDS.VizieR/J/ApJ/807/127
Title:
Properties of 70 RR Lyrae stars in the LMC bar
Short Name:
J/ApJ/807/127
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of the analysis of 70 RR Lyrae stars located in the bar of the Large Magellanic Cloud (LMC). Combining the spectroscopically determined metallicity of these stars from the literature with precise periods from the OGLE III catalog (Soszynski et al. 2009, J/AcA/59/1) and multi-epoch K_s_ photometry from the VISTA survey of the Magellanic Clouds system, we derive a new near-infrared period-luminosity-metallicity (PL_Ks_Z) relation for RR Lyrae variables. In order to fit the relation we use a fitting method developed specifically for this study. The zero-point of the relation is estimated two different ways: by assuming the value of the distance to the LMC and by using Hubble Space Telescope parallaxes of five RR Lyrae stars in the Milky Way (MW). The difference in distance moduli derived by applying these two approaches is ~0.2 mag. To investigate this point further we derive the PL_Ks_Z relation based on 23 MW RR Lyrae stars that had been analyzed in Baade-Wesselink studies. We compared the derived PL_Ks_Z relations for RR Lyrae stars in the MW and LMC. Slopes and zero-points are different, but still consistent within the errors. The shallow slope of the metallicity term is confirmed by both LMC and MW variables. The astrometric space mission Gaia is expected to provide a huge contribution to the determination of the RR Lyrae PL_Ks_Z relation; however, calculating an absolute magnitude from the trigonometric parallax of each star and fitting a PL_Ks_Z relation directly to period and absolute magnitude leads to biased results. We present a tool to achieve an unbiased solution by modeling the data and inferring the slope and zero-point of the relation via statistical methods.
5325. Properties of SCUBA cores in Perseus mol. cloud
ID:
ivo://CDS.VizieR/J/MNRAS/402/603
Title:
Properties of SCUBA cores in Perseus mol. cloud
Short Name:
J/MNRAS/402/603
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new analysis of the properties of star-forming cores in the Perseus molecular cloud, identified in SCUBA 850um data originally presented by Hatchell et al. (2005, Cat. J/A+A/440/151). Our goal is to determine which core properties can be robustly identified and which depend on the extraction technique. Four regions in the cloud are examined: NGC 1333, IC348/HH211, L1448 and L1455. We identify clumps of dust emission using two popular automated algorithms, clfind and gaussclumps, finding 85 and 122 clumps in total, respectively. Using the catalogues of Hatchell et al. (2005, Cat. J/A+A/440/151), we separate these clumps into starless, Class 0 and Class I cores.
5326. Properties of SDSS QSOs in the ChaMP
ID:
ivo://CDS.VizieR/J/ApJ/690/644
Title:
Properties of SDSS QSOs in the ChaMP
Short Name:
J/ApJ/690/644
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the spectral energy distributions and evolution of a large sample of optically selected quasars from the Sloan Digital Sky Survey that were observed in 323 Chandra images analyzed by the Chandra Multiwavelength Project. Our highest-confidence matched sample includes 1135 X-ray detected quasars in the redshift range 0.2<z<5.4, representing some 36Msec of effective exposure. We provide catalogs of QSO properties, and describe our novel method of calculating X-ray flux upper limits and effective sky coverage. Spectroscopic redshifts are available for about 1/3 of the detected sample; elsewhere, redshifts are estimated photometrically. We detect 56 QSOs with redshift z>3, substantially expanding the known sample. We find no evidence for evolution out to z~5 for either the X-ray photon index {Gamma} or for the ratio of optical/UV to X-ray flux {alpha}_ox_.
5327. Properties of Sgr Stars
ID:
ivo://CDS.VizieR/J/ApJ/889/63
Title:
Properties of Sgr Stars
Short Name:
J/ApJ/889/63
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using 3D positions and kinematics of stars relative to the Sagittarius (Sgr) orbital plane and angular momentum, we identify 166 Sgr stream members observed by the Apache Point Observatory Galactic Evolution Experiment (APOGEE) that also have Gaia DR2 astrometry. This sample of 63/103 stars in the Sgr trailing/leading arm is combined with an APOGEE sample of 710 members of the Sgr dwarf spheroidal core (385 of them newly presented here) to establish differences of 0.6dex in median metallicity and 0.1dex in [{alpha}/Fe] between our Sgr core and dynamically older stream samples. Mild chemical gradients are found internally along each arm, but these steepen when anchored by core stars. With a model of Sgr tidal disruption providing estimated dynamical ages (i.e., stripping times) for each stream star, we find a mean metallicity gradient of 0.12+/-0.03dex/Gyr for stars stripped from Sgr over time. For the first time, an [{alpha}/Fe] gradient is also measured within the stream, at 0.02_/-0.01dex/Gyr using magnesium abundances and at 0.04+/-0.01dex/Gyr^ using silicon, which imply that the Sgr progenitor had significant radial abundance gradients. We discuss the magnitude of those inferred gradients and their implication for the nature of the Sgr progenitor within the context of the current family of Milky Way satellite galaxies, and we suggest that more sophisticated Sgr models are needed to properly interpret the growing chemodynamical detail we have on the Sgr system.
5328. Properties of slowly rotating asteroids.
ID:
ivo://CDS.VizieR/J/A+A/654/A87
Title:
Properties of slowly rotating asteroids.
Short Name:
J/A+A/654/A87
Date:
22 Feb 2022
Publisher:
CDS
Description:
Recent results for asteroid rotation periods from the TESS mission showed how strongly previous studies have underestimated the number of slow rotators, revealing the importance of studying those targets. For most slowly rotating asteroids (those with P>12h), no spin and shape model is available because of observation selection effects. This hampers determination of their thermal parameters and accurate sizes. Also, it is still unclear whether signatures of different surface material properties can be seen in thermal inertia determined from mid-infrared thermal flux fitting. We continue our campaign in minimising selection effects among main belt asteroids. Our targets are slow rotators with low light-curve amplitudes. Our goal is to provide their scaled spin and shape models together with thermal inertia, albedo, and surface roughness to complete the statistics. Rich multi-apparition datasets of dense light curves are supplemented with data from Kepler and TESS spacecrafts. In addition to data in the visible range, we also use thermal data from infrared space observatories (mainly IRAS, Akari and WISE) in a combined optimisation process using the Convex Inversion Thermophysical Model. This novel method has so far been applied to only a few targets, and therefore in this work we further validate the method itself. We present the models of 16 slow rotators, including two updated models. All provide good fits to both thermal and visible data.The obtained sizes are on average accurate at the 5% precision level, with diameters found to be in the range from 25 to 145km. The rotation periods of our targets range from 11 to 59h, and the thermal inertia covers a wide range of values, from 2 to <400J/m^2^/s^1/2^/K, not showing any correlation with the period. With this work we increase the sample of slow rotators with reliable spin and shape models and known thermal inertia by 40%. The thermal inertia values of our sample do not display a previously suggested increasing trend with rotation period, which might be due to their small skin depth.
5329. Properties of Spitzer c2d dark clouds
ID:
ivo://CDS.VizieR/J/ApJS/181/321
Title:
Properties of Spitzer c2d dark clouds
Short Name:
J/ApJS/181/321
Date:
21 Oct 2021
Publisher:
CDS
Description:
The c2d Spitzer Legacy project obtained images and photometry with both IRAC and MIPS instruments for five large, nearby molecular clouds. Three of the clouds were also mapped in dust continuum emission at 1.1mm, and optical spectroscopy has been obtained for some clouds. This paper combines information drawn from studies of individual clouds into a combined and updated statistical analysis of star-formation rates and efficiencies, numbers and lifetimes for spectral energy distribution (SED) classes, and clustering properties. Current star-formation efficiencies range from 3% to 6%; if star formation continues at current rates for 10Myr, efficiencies could reach 15-30%. Star-formation rates and rates per unit area vary from cloud to cloud; taken together, the five clouds are producing about 260M_{sun}_ of stars per Myr.
5330. Properties of the AGN sample
ID:
ivo://CDS.VizieR/J/A+A/646/A96
Title:
Properties of the AGN sample
Short Name:
J/A+A/646/A96
Date:
21 Oct 2021
Publisher:
CDS
Description:
Feedback from active galactic nuclei (AGN) is thought to be key in shaping the life cycle of their host galaxies by regulating star-formation activity. Therefore, to understand the impact of AGN on star formation, it is essential to trace the molecular gas out of which stars form. In this paper we present the first systematic study of the CO properties of AGN hosts at z~=2 for a sample of 27 X-ray selected AGN spanning two orders of magnitude in AGN bolometric luminosity (logL_bol_/(erg/s)=44.7-46.9) by using ALMA Band 3 observations of the CO(3-2) transition (~1" angular resolution). To search for evidence of AGN feedback on the CO properties of the host galaxies, we compared our AGN with a sample of inactive (i.e., non-AGN) galaxies from the PHIBSS survey with similar redshift, stellar masses, and star-formation rates (SFRs). We used the same CO transition as a consistent proxy for the gas mass for the two samples in order to avoid systematics involved when assuming conversion factors (e.g., excitation corrections and CO). By adopting a Bayesian approach to take upper limits into account, we analyzed CO luminosities as a function of stellar masses and SFRs, as well as the ratio L'_CO(3-2)_-M* (a proxy for the gas fraction). The two samples show statistically consistent trends in the L'_CO(3-2)_-L_FIR_ and L'_CO(3-2)_-M* planes. However, there are indications that AGN feature lower CO(3-2) luminosities (0.4-0.7dex) than inactive galaxies at the 2-3 level when we focus on the subset of parameters where the results are better constrained (i.e., L_FIR_~=10^12.2^L_{sun}_ and M*>10^11^M_{sun}_) and on the distribution of the mean log(L'_CO(3-2)_/M*). Therefore, even by conservatively assuming the same excitation factor r31, we would find lower molecular gas masses in AGN, and assuming higher r31 would exacerbate this difference. We interpret our result as a hint of the potential effect of AGN activity (such as radiation and outflows), which may be able to heat, excite, dissociate, and/or deplete the gas reservoir of the host galaxies. Better SFR measurements and deeper CO observations for AGN as well as larger and more uniformly selected samples of both AGN and inactive galaxies are required to confirm whether there is a true difference between the two populations.