- ID:
- ivo://CDS.VizieR/J/A+A/603/A67
- Title:
- CRL618, MWC922 and M2-9 RRL spectra
- Short Name:
- J/A+A/603/A67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results from a pilot search for radio recombination line (RRL) emission at millimeter wavelengths in a small sample of pre-planetary nebulae (pPNe) and young PNe (yPNe) with emerging central ionized regions. Observations of the H30{alpha}, H31{alpha}, H39{alpha}, H41{alpha}, H48{beta}, H49{beta}, H51{beta}, and H55{gamma} lines at ~1 and ~3mm have been performed with the IRAM 30m radio telescope. These lines are excellent probes of the dense inner (<~150 au) and heavily obscured regions of these objects, where the yet unknown agents for PN-shaping originate. We detected mm-RRLs in three objects: CRL 618, MWC922, and M2-9. For CRL 618, the only pPN with previous published detections of H41{alpha}, H35{alpha}, and H30{alpha} emission, we find significant changes in the line profiles indicating that current observations are probing regions of the ionized wind with larger expansion velocities and mass-loss rate than ~29 years ago. In the case of MWC922, we observe a drastic transition from single-peaked profiles at 3mm (H39{alpha} and H41{alpha}) to double-peaked profiles at 1mm (H31{alpha} and H30{alpha}), which is consistent with maser amplification of the highest frequency lines; the observed line profiles are compatible with rotation and expansion of the ionized gas, probably arranged in a disk+wind system around a ~5-10M_{sun}_ central mass. In M2-9, the mm-RRL emission appears to be tracing a recent mass outburst by one of the stars of the central binary system. We present the results from non-LTE line and continuum radiative transfer models, which enables us to constrain the structure, kinematics, and physical conditions (electron temperature and density) of the ionized cores of our sample. We find temperatures Te~6000-17000K, mean densities ne~10^5^-10^8^cm^-3^, radial density gradients ne{prop.to}r^-alpha_n_^ whit alpha_n_~2-3.5, and motions of velocities of ~10-30km/s in the ionized wind regions traced by these mm-wavelength observations. We deduce mass-loss rates of dM_pAGB_/dt~=10^-6^-10^-7^M_{sun}_/yr, which are significantly higher than the values adopted by stellar evolution models currently in use and would result in a transition from the asymptotic giant branch to the PN phase faster than hitherto assumed.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/244/5
- Title:
- Crosscorrelation function (CCF) studies in GX 17+2
- Short Name:
- J/ApJS/244/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Neutron star Z-type sources provide a unique platform in order to understand the structure of accretion disk-corona geometry emitting close to the Eddington luminosity. Using RXTE and Nuclear Spectroscopic Telescope Array Mission (NuSTAR) satellite data, we performed crosscorrelation function (CCF) studies in GX 17+2 in order to constrain the size of the corona responsible for hard X-rays. From the RXTE data, we found that during horizontal and normal branches, the CCFs show anticorrelated hard (16-30keV) and soft (2-5keV) X-ray delays of the order of a few tens to hundred seconds with a mean correlation coefficient of 0.42+/-0.11. Few observations shows correlated lags and, on one occasion, coincident with radio emission. We also report an anticorrelated hard X-ray delay of 113+/-51s using the NuSTAR data of GX 17+2. Based on RXTE data, we find that soft and hard X-ray fluxes are varying, indicating the changes in the disk-corona structure during delays. We bridle the size of the corona using relativistic precession, transition layer models, and boundary layer models. Assuming the delays to be a readjustment timescale of the disk-corona structure, the height of the corona was estimated to be ~17-100km. Assuming that the inner region of the truncated disk is occupied by the corona, we constrain the coronal readjustment velocities (v_corona_={beta}v_disk_, where v_disk_ is the radial velocity component of the disk) of the order of {beta}=0.06-0.12. This study indicates that the observed delays are primarily dependent on the varying coronal readjustment velocities.
- ID:
- ivo://CDS.VizieR/J/ApJ/778/98
- Title:
- Cross-correlation of SDSS QSOs and BOSS galaxies
- Short Name:
- J/ApJ/778/98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the measurement of the two-point cross-correlation function (CCF) of 8198 Sloan Digital Sky Survey Data Release 7 quasars and 349608 Data Release 10 CMASS galaxies from the Baryonic Oscillation Spectroscopic Survey (BOSS) at 0.3<z<0.9. The CCF can be reasonably well fit by a power-law model {xi}_QG_(r)=(r/r_0_)^-{gamma}^ on projected scales of r_p_=2-25h^-1^Mpc with r_0_=6.61+/-0.25h^-1^Mpc and {gamma}=1.69+/-0.07. We estimate a quasar linear bias of b_Q_=1.38+/-0.10 at <z>{=}0.53 from the CCF measurements, which corresponds to a characteristic host halo mass of ~4x10^12^h^-1^M_{sun}_, compared with a ~10^13^h^-1^M_{sun}_ characteristic host halo mass for CMASS galaxies. Based on the clustering measurements, most quasars at {overline}{z}~0.5 are not the descendants of their higher luminosity counterparts at higher redshift, which would have evolved into more massive and more biased systems at low redshift. We divide the quasar sample in luminosity and constrain the luminosity dependence of quasar bias to be db_Q_/dlogL=0.20+/-0.34 or 0.11+/-0.32 (depending on different luminosity divisions) for quasar luminosities -23.5>M_i_(z=2)>-25.5, implying a weak luminosity dependence of clustering for luminous quasars at {overline}{z}~0.5. We compare our measurements with theoretical predictions, halo occupation distribution (HOD) models, and mock catalogs. These comparisons suggest that quasars reside in a broad range of host halos. The host halo mass distributions significantly overlap with each other for quasars at different luminosities, implying a poor correlation between halo mass and instantaneous quasar luminosity. We also find that the quasar HOD parameterization is largely degenerate such that different HODs can reproduce the CCF equally well, but with different satellite fractions and host halo mass distributions. These results highlight the limitations and ambiguities in modeling the distribution of quasars with the standard HOD approach.
- ID:
- ivo://CDS.VizieR/VII/201
- Title:
- Cross-Identifications in Abell and Zwicky clusters
- Short Name:
- VII/201
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new identification between Abell and Zwicky clusters of galaxies and vice versa is completed. Two convenient files are generated with necessary data for comparing both catalogs; remarks on the cluster matching are also included.
- 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.
- 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.
4538. 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.
