Search

Start Over Content Level Research
631. AGILE bright gamma-ray sources updated list
ID:
ivo://CDS.VizieR/J/A+A/558/A137
Title:
AGILE bright gamma-ray sources updated list
Short Name:
J/A+A/558/A137
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a variability study of a sample of bright {gamma}-ray (30MeV-50GeV ) sources. This sample is an extension of the first AGILE catalogue of -ray sources (1AGL), obtained using the complete set of AGILE observations in pointing mode performed during a 2.3 year period from July 9, 2007 until October 30, 2009. The dataset of AGILE pointed observations covers a long time interval and its {gamma}-ray data archive is useful for monitoring studies of medium-to-high brightness {gamma}-ray sources. In the analysis reported here, we used data obtained with an improved event filter that covers a wider field of view, on a much larger (about 27.5 months) dataset, integrating data on observation block time scales, which mostly range from a few days to thirty days. The data processing resulted in a better characterized source list than 1AGL was, and includes 54 sources, 7 of which are new high galactic latitude (|BII|>=5) sources, 8 are new sources on the galactic plane, and 20 sources from the previous catalogue with revised positions. Eight 1AGL sources (2 high-latitude and 6 on the galactic plane) were not detected in the final processing either because of low Observing Block (OB) exposure and/or due to their position in complex galactic regions. We report the results in a catalogue of all the detections obtained in each single OB, including the variability results for each of these sources. In particular, we found that 12 sources out of 42 or 11 out of 53 are variable, depending on the variability index used, where 42 and 53 are the number of sources for which these indices could be calculated. Seven of the 11 variable sources are blazars, the others are Crab pulsar+nebula, LS I +61 303, Cyg X-3, and 1AGLR J2021+4030.
632. AGILE Mini-Calorimeter {gamma}-ray burst catalog
ID:
ivo://CDS.VizieR/J/A+A/553/A33
Title:
AGILE Mini-Calorimeter {gamma}-ray burst catalog
Short Name:
J/A+A/553/A33
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Mini-Calorimeter of the AGILE satellite can observe the high-energy part of gamma-ray bursts with good timing capability. We present the data of the 85 hard gamma-ray bursts observed by the Mini-Calorimeter since the launch (April 2007) until October 2009. We report the timing data for 84 and spectral data for 21 bursts.
633. AGK1 catalog, -2{deg} 10'=<DE<=+1{deg} 10'
ID:
ivo://CDS.VizieR/I/310
Title:
AGK1 catalog, -2{deg} 10'=<DE<=+1{deg} 10'
Short Name:
I/310
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalogue contains 5954 stars obtained in the course of observational campaign of the AGK1 programme that is the German abbreviation, which stands for the catalogue of astronomical society. The observations were carried out at Nikolaev Astronomical Observatory (Ukraine) in 1876-1899 with the Reichenbach meridian circle made in 1825. Magnitude range of stars is from 2.2 to 9.1 The declination zone is from -2{deg}10' to +1{deg}10'. Fourteen stars from the Fundamental Catalogue were included in the catalogue, namely: 0542, 1364, 1409, 3276, 3397, 3446, 3602, 3748, 5001, 5082, 5571, 5629, 5681, 5825. The probable errors of RA and Dec are 28ms and 490mas correspondingly.
634. AGK3 Catalogue
ID:
ivo://CDS.VizieR/I/61B
Title:
AGK3 Catalogue
Short Name:
I/61B
Date:
21 Oct 2021
Publisher:
CDS
Description:
The AGK3 provides positions and proper motions for stars north of -2.5 degrees. For the most part, it contains the stars in the AGK2 but is based on newly remeasured reference stars whose positions were reduced to the FK4 system. A list of 446 AGK2 stars not in the AGK3 and of three new stars is provided. All plates were taken at the Bergedorf Observatory. In addition to the positions and proper motions, the catalog contains magnitudes and spectral types, the epoch of the observations, the epoch difference between the AGK2 and AGK3, and the BD numbers.
635. AGK3R
ID:
ivo://CDS.VizieR/I/161
Title:
AGK3R
Short Name:
I/161
Date:
21 Oct 2021
Publisher:
CDS
Description:
A catalog of positions of reference stars distributed uniformly on the celestial sphere north of declination -5 deg. contains meridian observations of 21,499 stars with a mean epoch 1958.5. This catalog was compiled from more than 300,000 observations made with 11 northern meridian circles during the period 1956 to 1963. The observations are on the FK4 system.
636. AGK3R mean positions and proper motions
ID:
ivo://CDS.VizieR/I/72
Title:
AGK3R mean positions and proper motions
Short Name:
I/72
Date:
21 Oct 2021
Publisher:
CDS
Description:
The AGK3R and SRS are lists of reference stars containing, respectively, 21,499 stars in the northern hemisphere and 20,500 stars in the southern hemisphere. This paper presents computations of proper motions of these two groups of stars that will permit the use of the observed positions away from the epochs of observation. Tables are presented summarizing the mean errors of AGK3R proper motions and the observational histories of AGK3R and SRS stars.
637. AGK3U
ID:
ivo://CDS.VizieR/I/176
Title:
AGK3U
Short Name:
I/176
Date:
21 Oct 2021
Publisher:
CDS
Description:
The AGK3U is a updated version of the AGK3 catalog in which new positions from the Palomar "Quick V" survey have been added to improve the AGK3 proper motions. It provides FK4/B1950.0 positions and proper motions for 170,464 stars north of -2.5 degrees declination, at an average epoch of 1950.62. The proper motions have a two dimensional formal mean error of 0.82 arcsec/century. In addition to the positions and proper motions, the catalog contains the AGK3 number, the mean errors of the positions and proper motion in each coordinate, the photographic magnitude, the spectral type, and the Palomar plate position, epoch, and mean error.
638. A global model for MC and Galactic Cepheids
ID:
ivo://CDS.VizieR/J/ApJ/748/107
Title:
A global model for MC and Galactic Cepheids
Short Name:
J/ApJ/748/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We perform a global fit to ~5000 radial velocity and ~177000 magnitude measurements in 29 photometric bands covering 0.3{mu}m to 8.0{mu}m distributed among 287 Galactic, Large Magellanic Cloud, and Small Magellanic Cloud Cepheids with P>10 days. We assume that the Cepheid light curves and radial velocities are fully characterized by distance, reddening, and time-dependent radius and temperature variations. We construct phase curves of radius and temperature for periods between 10 and 100 days, which yield light-curve templates for all our photometric bands and can be easily generalized to any additional band. With only four to six parameters per Cepheid, depending on the existence of velocity data and the amount of freedom in the distance, the models have typical rms light and velocity curve residuals of 0.05mag and 3.5km/s. The model derives the mean Cepheid spectral energy distribution and its derivative with respect to temperature, which deviate from a blackbody in agreement with metal-line and molecular opacity effects. We determine a mean reddening law toward the Cepheids in our sample, which is not consistent with standard assumptions in either the optical or near-IR. Based on stellar atmosphere models, we predict the biases in distance, reddening, and temperature determinations due to the metallicity and quantify the metallicity signature expected for our fit residuals.
639. AGN activity and black hole mass
ID:
ivo://CDS.VizieR/J/MNRAS/407/2399
Title:
AGN activity and black hole mass
Short Name:
J/MNRAS/407/2399
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the role of host galaxy classification and black hole mass (MBH) in a heterogeneous sample of 276 mostly nearby (z<0.1) X-ray and IR-selected active galactic nuclei (AGN).
640. AGN activity in isolated SDSS galaxies
ID:
ivo://CDS.VizieR/J/other/RMxAA/47.361
Title:
AGN activity in isolated SDSS galaxies
Short Name:
J/other/RMxAA/47
Date:
21 Oct 2021
Publisher:
CDS
Description:
We discuss the nature and origin of the nuclear activity observed in a sample of 292 SDSS narrow-emission-line galaxies, considered to have formed and evolved in isolation. All these galaxies are spiral like and show some kind of nuclear activity. The fraction of Narrow Line AGNs (NLAGNs) and Transition type Objects (TOs; a NLAGN with circumnuclear star formation) is relatively high, amounting to 64% of the galaxies. There is a definite trend for the NLAGNs to appear in early-type spirals, while the star forming galaxies and TOs are found in later-type spirals. We verify that the probability for a galaxy to show an AGN characteristic increases with the bulge mass of the galaxy (Torres-Papaqui et al. 2011), and find evidence that this trend is really a by-product of the morphology, suggesting that the AGN phenomenon is intimately connected with the formation process of the galaxies. Consistent with this interpretation, we establish a strong connection between the astration rate -- the efficiency with which the gas is transformed into stars - the AGN phenomenon, and the gravitational binding energy of the galaxies: the higher the binding energy, the higher the astration rate and the higher the probability to find an AGN. The NLAGNs in our sample are consistent with scaled-down or powered-down versions of quasars and Broad Line AGNs.

Limit your search

more »

more »

more »

more »

more »

more »

more »

more »