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21831. The Massive Compact Halo Object (MACHO) Project Data Archive
ID:
ivo://nci.org.au/macho
Title:
The Massive Compact Halo Object (MACHO) Project Data Archive
Short Name:
MACHO
Date:
23 Jul 2015 02:55:45
Publisher:
ivo://nci.org.au
Description:
The MACHO Project was a collaboration between scientists at the Mt. Stromlo and Siding Spring Observatories, the Center for Particle Astrophysics at the Santa Barbara, San Diego, and Berkeley campuses of the University of California, and the Lawrence Livermore National Laboratory. Our primary aim was to test the hypothesis that a significant fraction of the dark matter in the halo of the Milky Way is made up of objects like brown dwarfs or planets: these objects have come to be known as MACHOs, for MAssive Compact Halo Objects. The signature of these objects is the occasional amplification of the light from extragalactic stars by the gravitational lens effect. The amplification can be large, but events are extremely rare: it was necessary to monitor photometrically several million stars for a period of 10 years in order to obtain a useful detection rate. For this purpose we built a two channel system that employed eight 2048*2048 CCDs, mounted on the 50 inch telescope at Mt. Stromlo. The MACHO project data archive consists of approximately 127,000 two-colour images of fields collected between 1992 and 2003 covering the large and small Magellanic clouds and the galactic bulge and two-colour light-curves for approximately 18 million stars in the LMC and galactic bulge.
21832. The massive star population of Cygnus OB2
ID:
ivo://CDS.VizieR/J/MNRAS/449/741
Title:
The massive star population of Cygnus OB2
Short Name:
J/MNRAS/449/741
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have compiled a significantly updated and comprehensive census of massive stars in the nearby Cygnus OB2 association by gathering and homogenising data from across the literature. The census contains 169 primary OB stars, including 52 O-type stars and 3 Wolf-Rayet stars. Spectral types and photometry are used to place the stars in a Hertzprung-Russell diagram, which is compared to both non-rotating and rotating stellar evolution models, from which stellar masses and ages are calculated. The star formation history and mass function of the association are assessed, and both are found to be heavily influenced by the evolution of the most massive stars to their end states. We find that the mass function of the most massive stars is consistent with a "universal" power-law slope of {Gamma}=1.3. The age distribution inferred from stellar evolutionary models with rotation and the mass function suggest the majority of star formation occurred more or less continuously between 1 and 7Myr ago, in agreement with studies of low- and intermediate mass stars in the association. We identify a nearby young pulsar and runaway O-type star that may have originated in Cyg OB2 and suggest that the association has already seen its first supernova. Finally we use the census and mass function to calculate the total mass of the association of 16500^+3800^_-2800_M_{sun}, at the low end, but consistent with, previous estimates of the total mass of Cyg OB2. Despite this Cyg OB2 is still one of the most massive groups of young stars known in our Galaxy making it a prime target for studies of star formation on the largest scales.
21833. The MASSIVE survey : 116 candidate galaxies
ID:
ivo://CDS.VizieR/J/ApJ/795/158
Title:
The MASSIVE survey : 116 candidate galaxies
Short Name:
J/ApJ/795/158
Date:
21 Oct 2021
Publisher:
CDS
Description:
Massive early-type galaxies represent the modern day remnants of the earliest major star formation episodes in the history of the universe. These galaxies are central to our understanding of the evolution of cosmic structure, stellar populations, and supermassive black holes, but the details of their complex formation histories remain uncertain. To address this situation, we have initiated the MASSIVE Survey, a volume-limited, multi-wavelength, integral-field spectroscopic (IFS) and photometric survey of the structure and dynamics of the ~100 most massive early-type galaxies within a distance of 108 Mpc. This survey probes a stellar mass range M*>~10^11.5^ M_{sun}_ and diverse galaxy environments that have not been systematically studied to date. Our wide-field IFS data cover about two effective radii of individual galaxies, and for a subset of them, we are acquiring additional IFS observations on sub-arcsecond scales with adaptive optics. We are also acquiring deep K-band imaging to trace the extended halos of the galaxies and measure accurate total magnitudes. Dynamical orbit modeling of the combined data will allow us to simultaneously determine the stellar, black hole, and dark matter halo masses. The primary goals of the project are to constrain the black hole scaling relations at high masses, investigate systematically the stellar initial mass function and dark matter distribution in massive galaxies, and probe the late-time assembly of ellipticals through stellar population and kinematical gradients. In this paper, we describe the MASSIVE sample selection, discuss the distinct demographics and structural and environmental properties of the selected galaxies, and provide an overview of our basic observational program, science goals and early survey results.
21834. The MASSIVE survey. VI. Warm ionized gas.
ID:
ivo://CDS.VizieR/J/ApJ/837/40
Title:
The MASSIVE survey. VI. Warm ionized gas.
Short Name:
J/ApJ/837/40
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first systematic investigation of the existence, spatial distribution, and kinematics of warm ionized gas as traced by the [OII]3727{AA} emission line in 74 of the most massive galaxies in the local universe. All of our galaxies have deep integral-field spectroscopy from the volume- and magnitude-limited MASSIVE survey of early-type galaxies with stellar mass log(M_*_/M_{sun}_)>11.5 (M_K_<-25.3mag) and distance D<108Mpc. Of the 74 galaxies in our sample, we detect warm ionized gas in 28, which yields a global detection fraction of 38+/-6% down to a typical [OII] equivalent width limit of 2{AA}. MASSIVE fast rotators are more likely to have gas than MASSIVE slow rotators with detection fractions of 80+/-10% and 28+/-6%, respectively. The spatial extents span a wide range of radii (0.6-18.2kpc; 0.1-4R_e_), and the gas morphologies are diverse, with 17/28~61+/-9% being centrally concentrated, 8/28~29+/-9% exhibiting clear rotation out to several kiloparsecs, and 3/28~11+/-6% being extended but patchy. Three out of four fast rotators show kinematic alignment between the stars and gas, whereas the two slow rotators with robust kinematic measurements available exhibit kinematic misalignment. Our inferred warm ionized gas masses are roughly ~10^5^M_{sun}_. The emission line ratios and radial equivalent width profiles are generally consistent with excitation of the gas by the old underlying stellar population. We explore different gas origin scenarios for MASSIVE galaxies and find that a variety of physical processes are likely at play, including internal gas recycling, cooling out of the hot gaseous halo, and gas acquired via mergers.
21835. The mass of Jupiter
ID:
ivo://edu.gavo.org/eurovo/cosadie_jupiter_nass
Title:
The mass of Jupiter
Date:
27 Dec 2024 08:31:00
Publisher:
The GAVO DC team
Description:
Within this use case you determine the mass of Jupiter by observing the orbits of the Galileian moons and by inserting these data into Kepler's laws.
21836. The 2MASS point source catalog
ID:
ivo://org.gavo.dc/2mass/res/2mass/data
Title:
The 2MASS point source catalog
Short Name:
twomass.data
Date:
27 Dec 2024 08:31:04
Publisher:
The GAVO DC team
Description:
The 2MASS Point Source Catalogue, short a couple of exotic fields. We provide this data mainly for matching with other catalogs within our TAP service.
21837. The 2MASS Redshift Survey (2MRS)
ID:
ivo://CDS.VizieR/J/ApJS/199/26
Title:
The 2MASS Redshift Survey (2MRS)
Short Name:
J/ApJS/199/26
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of the 2MASS Redshift Survey (2MRS), a ten-year project to map the full three-dimensional distribution of galaxies in the nearby universe. The Two Micron All Sky Survey (2MASS) was completed in 2003 and its final data products, including an extended source catalog (XSC), are available online. The 2MASS XSC contains nearly a million galaxies with Ks<=13.5mag and is essentially complete and mostly unaffected by interstellar extinction and stellar confusion down to a galactic latitude of |b|=5{deg} for bright galaxies. Near-infrared wavelengths are sensitive to the old stellar populations that dominate galaxy masses, making 2MASS an excellent starting point to study the distribution of matter in the nearby universe. We selected a sample of 44599 2MASS galaxies with Ks<=11.75mag and |b|>=5{deg} (>=8{deg} toward the Galactic bulge) as the input catalog for our survey. We obtained spectroscopic observations for 11000 galaxies and used previously obtained velocities for the remainder of the sample to generate a redshift catalog that is 97.6% complete to well-defined limits and covers 91% of the sky. This provides an unprecedented census of galaxy (baryonic mass) concentrations within 300Mpc. Earlier versions of our survey have been used in a number of publications that have studied the bulk motion of the Local Group, mapped the density and peculiar velocity fields out to 50h^-1^Mpc, detected galaxy groups, and estimated the values of several cosmological parameters. Additionally, we present morphological types for a nearly complete sub-sample of 20860 galaxies with Ks<=11.25mag and |b|>=10{deg}.
21838. The MAST Image Scrapbook
ID:
ivo://irsa.ipac/MAST/Scrapbook
Title:
The MAST Image Scrapbook
Short Name:
MAST-Scrapbook
Date:
16 Mar 2017 01:00:00
Publisher:
NASA/IPAC Infrared Science Archive
Description:
The MAST Spectral/Image Scrapbook is designed to allow users to take a quick look at sample data in the MAST archive of a particular astronomical object of interest. It is set up here as an interoperability project between IRSA and MAST.
21839. The Mayrit catalogue
ID:
ivo://CDS.VizieR/J/A+A/478/667
Title:
The Mayrit catalogue
Short Name:
J/A+A/478/667
Date:
21 Oct 2021
Publisher:
CDS
Description:
The young sigma Orionis cluster is an indispensable basis for understanding the formation and evolution of stars, brown dwarfs and planetary-mass objects. Our knowledge of its stellar population is, however, incomplete. I present the Mayrit catalogue, that comprises most of the stars and high-mass brown dwarfs of the cluster. The basis of this work is an optical-near infrared correlation between the 2MASS and DENIS catalogues in a circular area of radius 30 arcmin centred on the OB-type binary sigma Ori AB. The analysis is supported on a bibliographic search of confirmed cluster members with features of youth and on additional X-ray, mid-infrared and astrometric data. I list 241 sigma Orionis stars and brown dwarfs with known features of youth, 97 candidate cluster members (40 are new) and 115 back- and foreground sources in the survey area. The 338 cluster members and member candidates constitute the Mayrit catalogue. This catalogue is a suitable input for studying the spatial distribution, multiplicity, properties and frequency of discs and the complete mass function of sigma Orionis.
21840. The M_BH_-{sigma} relation for active galaxies
ID:
ivo://CDS.VizieR/J/ApJ/809/20
Title:
The M_BH_-{sigma} relation for active galaxies
Short Name:
J/ApJ/809/20
Date:
21 Oct 2021
Publisher:
CDS
Description:
We create a baseline of the black hole (BH) mass (M_BH_)-stellar-velocity dispersion ({sigma}) relation for active galaxies, using a sample of 66 local (0.02<z<0.09) Seyfert-1 galaxies, selected from the Sloan Digital Sky Survey (SDSS). Analysis of SDSS images yields AGN luminosities free of host-galaxy contamination, and morphological classification. 51/66 galaxies have spiral morphology. Out of these, 28 bulges have Sersic index n<2 and are considered candidate pseudo-bulges, with eight being definite pseudo-bulges based on multiple classification criteria met. Only 4/66 galaxies show signs of interaction/merging. High signal-to-noise ratio Keck spectra provide the width of the broad H{beta} emission line free of Fe II emission and stellar absorption. AGN luminosity and H{beta} line widths are used to estimate M_BH_. The Keck-based spatially resolved kinematics is used to determine stellar-velocity dispersion within the spheroid effective radius ({sigma}_spat,reff_). We find that {sigma} can vary on average by up to 40% across definitions commonly used in the literature, emphasizing the importance of using self-consistent definitions in comparisons and evolutionary studies. The M_BH_-{sigma} relation for our Seyfert-1 galaxy sample has the same intercept and scatter as that of reverberation-mapped AGNs as well as that of quiescent galaxies, consistent with the hypothesis that our single epoch M_BH_ estimator and sample selection function do not introduce significant biases. Barred galaxies, merging galaxies, and those hosting pseudo-bulges do not represent outliers in the M_BH_-{sigma} relation. This is in contrast with previous work, although no firm conclusion can be drawn on this matter due to the small sample size and limited resolution of the SDSS images.

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