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471. Redshift of 97 spirals
ID:
ivo://CDS.VizieR/J/A+A/310/353
Title:
Redshift of 97 spirals
Short Name:
J/A+A/310/353
Date:
21 Oct 2021
Publisher:
CDS
Description:
Persistent claims have been made over the last ~15yr that extragalactic redshifts, when corrected for the Sun's motion around the Galactic centre, occur in multiples of ~24 or ~36km/s. A recent investigation by us of 40 spiral galaxies out to 1000km/s, with accurately measured redshifts, gave evidence of a periodicity ~37.2-37.7km/s. Here we extend our enquiry out to the edge of the Local Super cluster (~2600km/s), applying a simple and robust procedure to a total of 97 accurately determined redshifts. We find that, when corrected for related vectors close to recent estimates of the Sun's galactocentric motion, the redshifts of spirals are strongly periodic (P~37.6km/s). The formal confidence level of the result is extremely high, and the signal is seen independently with different radio telescopes. We also examine a further sample of 117 spirals observed with the 300-foot Green Bank telescope alone. The periodicity phenomenon appears strongest for the galaxies linked by group membership, but phase coherence probably holds over large regions of the Local Supercluster.
472. Relative proper motions in NGC 362
ID:
ivo://CDS.VizieR/J/A+AS/93/311
Title:
Relative proper motions in NGC 362
Short Name:
J/A+AS/93/311
Date:
22 Feb 2022
Publisher:
CDS
Description:
Relative proper motions are determined for stars brighter than B~=17mag in a 1.5{deg}x1.5{deg} field centered on the globular cluster NGC 362. Proper motions and membership probabilities are tabulated for 488 stars within 10.2' of the cluster center. 14 astrographic plates with epoch differences up to 92 years were completely scanned, and each detectable object was stored. Proper motions were computed with an iterative central-overlap technique. A modal proper motion accuracy of 0.9 milliarcsec/year (mas/a) was achieved. NGC 362 appears projected onto the Small Magellanic Cloud (SMC), allowing to measure the proper motion of the cluster relative to extragalactic background stars. SMC stars were identified by position, proper motion and colour; the mean proper motion of these SMC candidates agrees well with the proper motions of SMC members known from the literature. The proper motion of NGC 362 relative to the SMC is +3.5+/-0.8mas/a in right ascension and -2.6+/-0.8mas/a in declination. For reasonable assumptions on the absolute proper motion of the SMC, the absolute proper motion and space motion of NGC 362 are computed. NGC 362 exhibits a highly eccentric orbit, typical for a member of the halo subgroup of the galactic globular cluster system. The perigalactic distance of NGC 362 is very small (<~1kpc), which raises the interesting question of how the cluster can survive the many passages near the galactic bulge over its lifetime.
473. Results of obs with the 6-inch transit circle
ID:
ivo://CDS.VizieR/I/100A
Title:
Results of obs with the 6-inch transit circle
Short Name:
I/100A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog is a compilation of seven catalogs of positions derived from observations with the six-inch transit circle of the U. S. Naval Observatory. The observations were obtained between 1911 and 1971 and were published in the catalogs: W210, W025, W150, W250, W350, W450, and W550. Proper motions and, in most catalogs, spectral types were added from other sources.
474. Revised coordinates for SGC galaxies
ID:
ivo://CDS.VizieR/J/PASP/101/360
Title:
Revised coordinates for SGC galaxies
Short Name:
J/PASP/101/360
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have determined improved positions for 373 galaxies listed in the Southern Galaxy Catalogue of Corwin, de Vaucouleurs, and de Vaucouleurs (1985, Cat. VII/116) as having poor coordinates. The revised coordinates are expected to be good to 6 arcsec (rms) in each coordinate.
475. Revised Luyten Half-Second Catalogue
ID:
ivo://CDS.VizieR/I/279
Title:
Revised Luyten Half-Second Catalogue
Short Name:
I/279
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present refined coordinates and proper motion data for the high proper motion (HPM) stars in the Luyten Half-Second (LHS) catalogue. The positional uncertainty in the original Luyten catalogue is typically >10" and is often >30". We have used the digital scans of the Palomar Observatory Sky Survey (POSS) I and POSS II plates to derive more accurate positions and proper motions of the objects. Out of the 4470 candidates in the LHS catalogue, 4323 objects were manually re-identified in the POSS I and POSS II scans. A small fraction of the stars were not found due to the lack of finder charts and digitized POSS II scans. The uncertainties in the revised positions are typically ~2", but can be as high as ~8" in a few cases, which is a large improvement over the original data. Cross-correlation with the Tycho-2 and Hipparcos catalogues yielded 819 candidates (with m_R_<~12). For these brighter sources, the position and proper motion data were replaced with the more accurate Tycho/Hipparcos data. In total, we have revised proper motion measurements and coordinates for 4040 stars and revised coordinates for 4330 stars. In the printed version of the paper, we present the updated coordinates and proper motion information on 528 sources which represent the high proper motion subset ({mu}>1"/yr) of the LHS catalogue. The electronic version contains the updated information on all the 4470 stars in the LHS catalogue.
476. Revisiting the Cygnus OB associations
ID:
ivo://CDS.VizieR/J/MNRAS/508/2370
Title:
Revisiting the Cygnus OB associations
Short Name:
J/MNRAS/508/2370
Date:
24 Jan 2022 09:16:32
Publisher:
CDS
Description:
OB associations play an important role in Galactic evolution, though their origins and dynamics remain poorly studied, with only a small number of systems analysed in detail. In this paper we revisit the existence and membership of the Cygnus OB associations. We find that of the historical OB associations only Cyg OB2 and OB3 stand out as real groups. We search for new OB stars using a combination of photometry, astrometry, evolutionary models and an SED fitting process, identifying 4680 probable OB stars with a reliability of >90%. From this sample we search for OB associations using a new and flexible clustering technique, identifying 6 new OB associations. Two of these are similar to the associations Cyg OB2 and OB3, though the others bear no relationship to any existing systems. We characterize the properties of the new associations, including their velocity dispersions and total stellar masses, all of which are consistent with typical values for OB associations. We search for evidence of expansion and find that all are expanding, albeit anistropically, with stronger and more significant expansion in the direction of Galactic longitude. We also identify two large-scale (160pc and 25km/s) kinematic expansion patterns across the Cygnus region, each including three of our new associations, and attribute this to the effects of feedback from a previous generation of stars. This work highlights the need to revisit the existence and membership of the historical OB associations, if they are to be used to study their properties and dynamics.
477. Rho Oph Near-IR Positions and Photometry
ID:
ivo://CDS.VizieR/J/ApJS/112/109
Title:
Rho Oph Near-IR Positions and Photometry
Short Name:
J/ApJS/112/109
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains the tabulated results from a three-color (JHK) near-Infrared imaging survey of the Rho Ophiuchi star-forming cloud core. The NIR imaging observations were acquired using the SQIID instrument on the Kitt Peak 1.3m telescope from June 4-10, 1993 and April 23-28, 1994. The survey covered one square degree (2.2pc by 2.2pc). The catalog contains 4495 sources with both J2000.0 and B1950.0 coordinates for each source and its J, H, and K magnitudes and/or upper their limits. The Rho Ophiuchi clouds are of great interest for star formation studies, since they include the nearest example of a currently forming star cluster. The absolute positions in RA and Dec were determined for each individual source by using a centering algorithm in the IRAF package APPHOT to obtain center positions in pixels which were then merged into a single common positional grid. Absolute stellar coordinates were determined by comparing the authors positional database with the positions of 36 HST Guide Star Catalog stars spread out over the survey field. These were used to determine a plate scale and rotation which was used to generate the final list of source positions. The position determination technique and the photometric data reduction and calibration is discussed in detail in the source reference.
478. rho Oph proper motions and photometry
ID:
ivo://CDS.VizieR/J/A+A/597/A90
Title:
rho Oph proper motions and photometry
Short Name:
J/A+A/597/A90
Date:
21 Oct 2021
Publisher:
CDS
Description:
We aim at performing a kinematic census of young stellar objects (YSOs) in the rho Ophiuchi F core and partially in the E core of the L1688 dark cloud. We run a proper motion program at the ESO New Technology Telescope (NTT) with the Son of ISAAC (SOFI) instrument over nine years in the near-infrared. We complemented these observations with various public image databases to enlarge the time base of observations and the field of investigation to 0.5{deg}x0.5{deg}. We derived positions and proper motions for 2213 objects. From these, 607 proper motions were derived from SOFI observations with a ~1.8mas/yr accuracy while the remaining objects were measured only from auxiliary data with a mean precision of about 3mas/yr. We performed a kinematic analysis of the most accurate proper motions derived in this work, which allowed us to separate cluster members from field stars and to derive the mean properties of the cluster. From the kinematic analysis we derived a list of 68 members and 14 candidate members, comprising 26 new objects with a high membership probability.
479. rho Oph region revisited with Gaia EDR3
ID:
ivo://CDS.VizieR/J/A+A/652/A2
Title:
rho Oph region revisited with Gaia EDR3
Short Name:
J/A+A/652/A2
Date:
22 Feb 2022
Publisher:
CDS
Description:
Young and embedded stellar populations are important probes of the star formation process. Their properties and the environments they create have the potential to affect the formation of new planets. Paradoxically, we have a better census of nearby embedded young populations than of the slightly more evolved optically visible young populations. The high accuracy measurements and all-sky coverage of Gaia data are about to change this situation. This work aims to construct the most complete sample to date of YSOs in the {rho} Oph region. We compile a catalog of 1114 Ophiuchus YSOs from the literature and crossmatch it with the Gaia EDR3, Gaia-ESO, and APOGEE-2 surveys. We apply a multivariate classification algorithm to this catalog to identify new, co- moving population candidates. We find 191 high-fidelity new YSO candidates in the Gaia EDR3 catalog belonging to the {rho} Oph region. The new sources appear to be mainly Class III M-stars and substellar objects and are less extincted than the known members, while we find that 28 of previously unknown sources are YSOs with circumstellar disks (Class I or Class II). The analysis of the proper motion distribution of the entire sample reveals a well-defined bimodality, implying two distinct populations sharing a similar 3D volume. The first population comprises young stars' clusters around the {rho} Ophiuchi star and the main Ophiuchus clouds (L1688, L1689, L1709). In contrast, the second population is slightly older (~10Myr), more dispersed, has a distinct proper motion, and is possibly from the Upper-Sco group. The two populations are moving away from each other at about 4.1km/s and will no longer overlap in about 4Myr. Finally, we flag 17 sources in the literature sample as likely impostors, which are sources that exhibit large deviations from the average properties of the {rho} Oph population. Our results show the importance of accurate 3D space and motion information for improved stellar population analysis.
480. Rich Clusters of Galaxies
ID:
ivo://CDS.VizieR/VII/110A
Title:
Rich Clusters of Galaxies
Short Name:
VII/110A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is an all-sky catalog of 4073 rich clusters of galaxies, each having at least 30 members within the magnitude range m_3_ to m_3_ + 2 (m_3_ is the magnitude of the third brightest cluster member) and each with a nominal redshift less than 0.2. The southern data have been collected from a survey of UK 1.2 m Schmidt telescope IIIa-J plates and films and have been reduced to the systems defined by the northern data previously published by G.O. Abell. A revised northern catalog, including Bautz-Morgan types and redshifts where known, is also included.

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