- ID:
- ivo://CDS.VizieR/J/AJ/114/222
- Title:
- Cross identifications in NGC 1502
- Short Name:
- J/AJ/114/222
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In studying this region Purgathofer (1964AnWie..26...37P) [the SIMBAD numbering], Hoag et al.(1961PUSNO..17..343H), and Dombrovskii and Hagen-Thorn (1964TrLen..20...75D) each set up their own numbering system; subsequent authors used one or another of those or variants or combinations. The region covered is 2 degrees in diameter, centered at: (2000) RA 04 04 53.28 dec +62 19 20.7. This is about 15' west of the cluster, the position of HD 25290.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/IV/30
- Title:
- Cross-id. of stars with high-proper motions. V2.
- Short Name:
- IV/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue of stars with high-proper motions (more than 0.04"/year) has been compiled using original definitions from catalogue FONAK 1.1, the data of catalogues Hipparcos, Tycho-2, CMC (STAR 11), PPM, NPM1, NPM2, UCAC2 (up to +40 degrees in declination and going up to +52 degrees in some areas), GCVS, XZ80Q, Pul-3, PUL2, NLTT, LHS, Lowell Proper Motion, Bruce Proper Motion as well as the data of about 770 other published sources. The list consist of 514100 such stars with limiting magnitude 16 (companions for multiple systems up to 17) in a declination zone from -2.5 to +90 degrees. Besides astrometric parameters (equatorial coordinates, proper motions, estimations of stars magnitudes) the catalogue includes some astrophysical characteristics (magnitudes in UBVRIJHK system, radial velocities, spectra, luminosity class, metallicity; flags of multiple system, of variable star and other). For convenience of usage original numbers of stars from different catalogues the author's lists of stars and basic sources are given too. At present the catalogue includes codes of 63 catalogues and author's lists of stars. Cross index list is given by a file of 493200 stars arranged on right ascension. Star information is recorded in a digital integer form with one line. Thus maximum amount of star numbers from catalogues and author's lists does not exceed 10 (if more, the number of next lines for star is increased by unit). Beginning the second line there are blanks in the column declination if star information is recorded in several lines. Cross index list is regularly supplemented.
- ID:
- ivo://CDS.VizieR/J/ApJ/833/196
- Title:
- Cross sections produced by ^3^He reactions
- Short Name:
- J/ApJ/833/196
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ^3^He abundance in impulsive solar energetic particle (SEP) events is enhanced up to several orders of magnitude compared to its photospheric value of [^3^He]/[^4^He] = 1-3 x 10^-4^. Interplanetary magnetic field and timing observations suggest that these events are related to solar flares. Observations of ^3^He in flare-accelerated ions would clarify the relationship between these two phenomena. Energetic ^3^He interactions in the solar atmosphere produce gamma-ray nuclear-deexcitation lines, both lines that are also produced by protons and {alpha} particles and lines that are essentially unique to ^3^He. Gamma-ray spectroscopy can, therefore, reveal enhanced levels of accelerated ^3^He. In this paper, we identify all significant deexcitation lines produced by ^3^He interactions in the solar atmosphere. We evaluate their production cross sections and incorporate them into our nuclear deexcitation-line code. We find that enhanced ^3^He can affect the entire gamma-ray spectrum. We identify gamma-ray line features for which the yield ratios depend dramatically on the ^3^He abundance. We determine the accelerated ^3^He/{alpha} ratio by comparing these ratios with flux ratios measured previously from the gamma-ray spectrum obtained by summing the 19 strongest flares observed with the Solar Maximum Mission Gamma-Ray Spectrometer. All six flux ratios investigated show enhanced ^3^He, confirming earlier suggestions. The ^3^He/{alpha} weighted mean of these new measurements ranges from 0.05 to 0.3 (depending on the assumed accelerated {alpha}/proton ratio) and has a <1 x 10^-3^ probability of being consistent with the photospheric value. With the improved code, we can now exploit the full potential of gamma-ray spectroscopy to establish the relationship between flare-accelerated ions and ^3^He-rich SEPs.
4514. 3CRSnapshots
- ID:
- ivo://3CRSnapshots
- Title:
- 3CRSnapshots
- Short Name:
- 3CRSnap
- Date:
- 09 May 2019 11:36:55
- Publisher:
- 3CR Snapshot Team
- Description:
- The naming authority for the 3CRSnapshot resources managed at the Observatoire de Strasbourg
- ID:
- ivo://CDS.VizieR/J/PASP/97/932
- Title:
- 3CR Source Identifications
- Short Name:
- J/PASP/97/932
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains the third major update of new optical and radio data for the strong sources in the Revised Third Cambridge Catalogue (3CR). Positions, redshifts, magnitudes, and identifications are included, as well as some radio data for 298 3CR sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/841/111
- Title:
- C3R2 survey: high-confidence redshifts from DR1
- Short Name:
- J/ApJ/841/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A key goal of the Stage IV dark energy experiments Euclid, LSST, and WFIRST is to measure the growth of structure with cosmic time from weak lensing analysis over large regions of the sky. Weak lensing cosmology will be challenging: in addition to highly accurate galaxy shape measurements, statistically robust and accurate photometric redshift (photo-z) estimates for billions of faint galaxies will be needed in order to reconstruct the three-dimensional matter distribution. Here we present an overview of and initial results from the Complete Calibration of the Color-Redshift Relation (C3R2) survey, which is designed specifically to calibrate the empirical galaxy color-redshift relation to the Euclid depth. These redshifts will also be important for the calibrations of LSST and WFIRST. The C3R2 survey is obtaining multiplexed observations with Keck (DEIMOS, LRIS, and MOSFIRE), the Gran Telescopio Canarias (GTC; OSIRIS), and the Very Large Telescope (VLT; FORS2 and KMOS) of a targeted sample of galaxies that are most important for the redshift calibration. We focus spectroscopic efforts on undersampled regions of galaxy color space identified in previous work in order to minimize the number of spectroscopic redshifts needed to map the color-redshift relation to the required accuracy. We present the C3R2 survey strategy and initial results, including the 1283 high-confidence redshifts obtained in the 2016A semester and released as Data Release 1.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/1562
- Title:
- CRTS close supermassive black hole binaries
- Short Name:
- J/MNRAS/453/1562
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Hierarchical assembly models predict a population of supermassive black hole (SMBH) binaries. These are not resolvable by direct imaging but may be detectable via periodic variability (or nanohertz frequency gravitational waves). Following our detection of a 5.2-year periodic signal in the quasar PG 1302-102, we present a novel analysis of the optical variability of 243 500 known spectroscopically confirmed quasars using data from the Catalina Real-time Transient Survey (CRTS) to look for close (<0.1pc) SMBH systems. Looking for a strong Keplerian periodic signal with at least 1.5 cycles over a baseline of nine years, we find a sample of 111 candidate objects. This is in conservative agreement with theoretical predictions from models of binary SMBH populations. Simulated data sets, assuming stochastic variability, also produce no equivalent candidates implying a low likelihood of spurious detections. The periodicity seen is likely attributable to either jet precession, warped accretion discs or periodic accretion associated with a close SMBH binary system. We also consider how other SMBH binary candidates in the literature appear in CRTS data and show that none of these are equivalent to the identified objects. Finally, the distribution of objects found is consistent with that expected from a gravitational-wave-driven population. This implies that circumbinary gas is present at small orbital radii and is being perturbed by the black holes. None of the sources is expected to merge within at least the next century. This study opens a new unique window to study a population of close SMBH binaries that must exist according to our current understanding of galaxy and SMBH evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/645/A102
- Title:
- Crust structure of neutron stars
- Short Name:
- J/A+A/645/A102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The thermal evolution of neutron stars in soft X-ray transients (SXTs) is sensitive to the equation of state, nucleon superfluidity, and the composition and structure of the crust. Carrying out comparisons of the observations of their crust cooling with simulations offers a powerful tool for verifying theoretical models of dense matter. We study the effect of physics input on the thermal evolution of neutron stars in SXTs. In particular, we consider different modern models of the sources of deep crustal heating during accretion episodes and the effects brought on by impurities embedded in the crust during its formation. We simulated the thermal structure and evolution of episodically accreting neutron stars under different assumptions regarding the crust composition and on the distribution of heat sources and impurities. For the non-accreted crust, we considered the nuclear charge fluctuations that arise at crust formation. For the accreted crust, we compared different theoretical models of composition and internal heating. We also compared the results of numerical simulations to observations of the crust cooling in SXT MXB 1659-29. The non-accreted part of the inner crust of a neutron star can have a layered structure, with almost pure crystalline layers interchanged with layers composed of mixtures of different nuclei. The latter layers have relatively low thermal conductivities, which has an effect on the thermal evolution of the transients. The impurity distribution in the crust strongly depends on models of the dense matter and the crust formation scenario. The shallow heating that is needed to reach an agreement between the theory and the observations depends on characteristics of the crust and envelope.
4519. Crux region redshifts
- ID:
- ivo://CDS.VizieR/J/A+AS/127/463
- Title:
- Crux region redshifts
- Short Name:
- J/A+AS/127/463
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In our systematic optical galaxy search behind the southern Milky Way, 3760 (mostly unknown) galaxies with diameters D>0.2' were identified in the Crux region (287{deg}<~l<~318{deg}, |b|<~10{deg}, Woudt & Kraan-Korteweg 1998, in press). Prior to this investigation, only 65 of these galaxies had known redshifts. In order to map the galaxy distribution in redshift space we obtained spectra for 226 bright (B_J_<~18.0mag) objects with the 1.9m telescope of the South African Astronomical Observatory (SAAO). Redshifts could be determined for 209 objects, of which 173 have good signal-to-noise ratios. Of the 36 tentative redshifts, four are confirmed through independent values in the literature. The redshifts of three objects indicate them to be galactic in origin. One of these confirms a suspected Planetary Nebula. For 17 of the galaxies, no redshift could be determined due to poor signal-to-noise ratios. In addition, 26 redshifts have have been measured in the Hydra-Antlia region investigated earlier (Kraan-Korteweg et al., 1995, Cat. <J/A+A/297/617>), of which one is a tentative estimate. Two main structures crossing the Galactic Plane in the Crux region have now become clear. A narrow, nearby filament from (l, b)=(340{deg}, -25{deg}) to the Centaurus cluster can be traced. This filament runs almost parallel to the extension of the Hydra-Antlia clusters found earlier and is part of what we have earlier termed the ``Centaurus Wall'' extending in redshift-space between 0<=v<=6000km/s (Fairall & Paverd 1995, in Wide-Field Spedctroscopy and the Distant Universe, p. 121). The main outcome of this survey however, is the recognition of another massive extended structure between 4000<=v<=8000km/s. This broad structure, dubbed the Norma Supercluster (Woudt et al. 1997, in press), runs nearly parallel to the Galactic Plane from Vela to ACO 3627 (its centre) from where it continues to the Pavo cluster. This massive structure is believed to be associated with the Great Attractor. The survey has furthermore revealed a set of cellular structures, similar to those seen in redshift space at higher galactic latitudes, but never before seen so clearly behind the Milky Way.
- ID:
- ivo://CDS.VizieR/J/A+A/506/1501
- Title:
- CrVIII radiative and excitation rates
- Short Name:
- J/A+A/506/1501
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we report on calculations of energy levels, radiative rates, oscillator strengths, line strengths, and effective collision strengths for transitions among the lowest 362 levels of the (1s^2^2s^2^2p^6^) 3s^2^3p^5^, 3s3p^6^, 3s^2^3p^4^3d, 3s3p^5^3d, 3s^2^3p^3^3d^2^, 3s3p^4^3d^2^, 3p^6^3d, and 3s^2^3p^4^4l configurations of Cr VIII.
