- ID:
- ivo://CDS.VizieR/J/ApJ/408/305
- Title:
- Cat of Stellar Lyman-Alpha Fluxes
- Short Name:
- J/ApJ/408/305
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The data file gives the measured Lyman alpha flux or upper limits for 275 stars as derived from IUE spectra. The file is a subset of Table 1 of Landsman and Simon in that when a star had multiple measurements, only the best measurement is included in this table. The spectral types, V and B-V magnitudes in the table are culled from various sources as described in the paper. Most of the measurements are derived from low-dispersion spectra, and those derived from high-dispersion spectra are flagged. Each measurement was assigned a data quality code according to the signal to noise after removal of the diffuse Lyman alpha background emission. -1 - upper limit 1 - good quality 2 - fair quality 3 - poor quality 4 - contains saturated pixels The final column gives the ratio of the Ly alpha flux to the total bolometric flux of the star, determined as described in the paper. A roundoff was applied to the fluxes listed here to give the fluxes listed in Table 1 of Landsman and Simon.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/569/A7
- Title:
- CB17 dust emission (100-500um), N(H) and T maps
- Short Name:
- J/A+A/569/A7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The initial conditions for the gravitational collapse of molecular cloud cores and the subsequent birth of stars are still not well constrained. The characteristic cold temperatures (~10K) in such regions require observations at sub-millimetre and longer wavelengths. The Herschel Space Observatory and complementary ground-based observations presented in this paper have the unprecedented potential to reveal the structure and kinematics of a prototypical core region at the onset of stellar birth. This paper aims to determine the density, temperature, and velocity structure of the star-forming Bok globule CB 17. This isolated region is known to host (at least) two sources at different evolutionary stages: a dense core, SMM1, and a Class I protostar, IRS. We modeled the cold dust emission maps from 100{mu}m to 1.2mm with both a modified blackbody technique to determine the optical depth-weighted line-of-sight temperature and column density and a ray-tracing technique to determine the core temperature and volume density structure. Furthermore, we analysed the kinematics of CB17 using the high-density gas tracer N_2_H^+
- ID:
- ivo://CDS.VizieR/J/A+A/501/801
- Title:
- CBI sample at 4.85GHz and 10.45GHz
- Short Name:
- J/A+A/501/801
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the flux density measurements at 4.85GHz and 10.45GHz of a sample of 5998 NVSS radio sources with the Effelsberg 100m telescope. The initial motivation was the need to identify the NVSS radio sources that could potentially contribute significant contaminating flux in the frequency range at which the Cosmic Background Imager experiment operated.
2804. 3C 295 BRri photometry
- ID:
- ivo://CDS.VizieR/J/A+A/285/785
- Title:
- 3C 295 BRri photometry
- Short Name:
- J/A+A/285/785
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed the cluster Cl 1409+524 (z=0.46) with an imaging Fabry-Perot interferometer. A sequence of Fabry-Perot images (FWHM=1.0-1.3nm) was used to search for redshifted [OII]{lambda}372.7nm- and [OIII]{lambda}500.7nm line emission. We studied 144 galaxies up to a limiting continuum R-band magnitude of 22.5mag within 1 Mpc around the cluster center. Previously known emission-line galaxies in the cluster were confirmed and 17 new members with emission lines were found. Their star formation rate of 1-2M_{sun}_/yr is typical for normal spirals. We have imaged the cluster with broad band B, R and seven intermediate band filters (FWHM=10.0-20.0nm) in order to derive low-resolution spectral energy distributions of cluster galaxies. These were fitted by template spectra to estimate Hubble class and redshifts. Based on this decomposition, we derived a percentage of emission-line galaxies of 40+/-11%.
- ID:
- ivo://CDS.VizieR/J/ApJS/115/185
- Title:
- 3C 390.3 BVRI and H photometry
- Short Name:
- J/ApJS/115/185
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of a ground-based optical monitoring campaign on 3C 390.3 in 1994-1995 are presented. The broadband fluxes (B, V, R, and I), the spectrophotometric optical continuum flux F_{lambda}_(5177{AA}), and the integrated emission-line fluxes of H{alpha}, H{beta}, H{gamma}, He I 5876, and He II {lambda}4686 all show a nearly monotonic increase with episodes of milder short-term variations superposed. The amplitude of the continuum variations increases with decreasing wavelength (4400-9000{AA}). The optical continuum variations follow the variations in the ultraviolet and X-ray with time delays, measured from the centroids of the cross-correlation functions, typically around 5 days, but with uncertainties also typically around 5 days; zero time delay between the high-energy and low-energy continuum variations cannot be ruled out. The strong optical emission lines H{alpha}, H{beta}, H{gamma}, and He I {lambda}5876 respond to the high-energy continuum variations with time delays typically about 20 days, with uncertainties of about 8 days. There is some evidence that He II {lambda}4686 responds somewhat more rapidly, with a time delay of around 10 days, but again, the uncertainties are quite large (~8 days). The mean and rms spectra of the H{alpha} and H{beta} line profiles provide indications for the existence of at least three distinct components located at +/-4000 and 0km/s relative to the line peak. The emission-line profile variations are largest near line center.
2806. C3 by collision with H2
- ID:
- ivo://CDS.VizieR/J/A+A/657/A55
- Title:
- C3 by collision with H2
- Short Name:
- J/A+A/657/A55
- Date:
- 21 Mar 2022 09:24:59
- Publisher:
- CDS
- Description:
- An accurate analysis of the physical-chemical conditions in the regions of the interstellar medium in which C_3_ is observed requires knowing the collisional rate coefficients of this molecule with He, H_2_, electrons, and H. The main goals of this study are to present the first potential energy surface for the C_3_ +H_2_ complex, to study the dynamics of the system, and to report a set of rate coefficients at low temperature for the lower rotational states of C_3_ with para- and ortho-H_2_. Methods. A large grid of ab initio energies was computed at the explicitly correlated coupled-cluster with single-, double-, and perturbative triple-excitation level of theory, together with the augmented correlation-consistent quadruple zeta basis set (CCSD(T)-F12a/aug-cc-pVQZ). This grid of energies was fit to an analytical function. The potential energy surface was employed in close- coupling calculations at low collisional energies. We present a high-level four-dimensional potential energy surface (PES) for studying the collision of C_3_ with H_2_ . The global minimum of the surface is found in the linear HH-CCC configuration. Rotational deexcitation state-to-state cross sections of C_3_ by collision with para- and ortho-H_2_ are computed. Furthermore, a reduced two-dimensional surface is developed by averaging the surface over the orientation of H_2_. The cross sections for the collision with para-H_2_ using this approximation and those from the four-dimensional PES agree excellently. Finally, a set of rotational rate coefficients for the collision of C_3_ with para- and ortho-H_2_ at low temperatures are reported.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A107
- Title:
- 3C 129 candidate cluster galaxies
- Short Name:
- J/A+A/644/A107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of 261 new infrared selected members of the 3C 129 galaxy cluster. The cluster, located at z=0.02, forms part of the Perseus-Pisces filament and is obscured at optical wavelengths due to its location in the zone of avoidance. We identified these galaxies using the J- and K-band imaging data provided by the UKIDSS Galactic Plane Survey within an area with a radius of 1.1{deg} centred on the X-ray emission of the cluster at (l, b) = (160.52{deg}, 0.27{deg}). A total of 26 of the identified galaxy members have known redshifts 24 of which are from our 2016 Westerbork HI survey and two are from optical spectroscopy. An analysis of the galaxy density at the core of the 3C 129 cluster shows it to be less dense than the Coma and Norma clusters, but comparable to the galaxy density in the core of the Perseus cluster. From an assessment of the spatial and velocity distributions of the 3C 129 cluster galaxies that have redshifts, we derived a velocity of cz=5227+/-171km/s and=1097+/-252km/s for the main cluster, with a substructure in the cluster outskirts at cz=6923+/-71km/s with {sigma}=422+/-100km/s. The presence of this substructure is consistent with previous claims based on the X-ray analysis that the cluster is not yet virialised and may have undergone a recent merger.
- ID:
- ivo://CDS.VizieR/J/AJ/137/236
- Title:
- CC Com and BV Dra light curves
- Short Name:
- J/AJ/137/236
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on O-C curves, we present detailed period investigations of two weak-contact binaries CC Com and BV Dra. It is found that the periods of these two binaries have varied in a cyclic variation way superposed on a secular period change. The periods and amplitudes of the cyclic variations are P_3_=23.6(+/-0.4)yr and A=0.0028(+/-0.0003)d for CC Com and P_3_=23.8(+/-0.6)yr and A=0.0029(+/-0.0003)d for BV Dra.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/15
- Title:
- CCCP: Carina's diffuse X-ray emission
- Short Name:
- J/ApJS/194/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 1.42deg^2^ mosaic of diffuse X-ray emission in the Great Nebula in Carina from the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer camera. After removing >14000 X-ray point sources from the field, we smooth the remaining unresolved emission, tessellate it into segments of similar apparent surface brightness, and perform X-ray spectral fitting on those tessellates to infer the intrinsic properties of the X-ray-emitting plasma. By modeling faint resolved point sources, we estimate the contribution to the extended X-ray emission from unresolved point sources and show that the vast majority of Carina's unresolved X-ray emission is truly diffuse. Line-like correlated residuals in the X-ray spectral fits suggest that substantial X-ray emission is generated by charge exchange at the interfaces between Carina's hot, rarefied plasma and its many cold neutral pillars, ridges, and clumps.
- ID:
- ivo://CDS.VizieR/VIII/30
- Title:
- 5C14/5C15/5C16 Radio Survey at 408 and 1407 MHz
- Short Name:
- VIII/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains the fourteenth, fifteenth, and sixteenth sections of the 5C Cambridge survey of radio sources. This catalog reports further 408 and 1407 MHz observations of the 5C12 area (Benn et al. 1982), which were carried out with the One-Mile Telescope at Cambridge to provide more accurate positions for the 5C12 sources and to extend the 5C12 catalog. Positions and flux densities were measured for 691 sources in a 5 degree x 5 degree area near the north galactic pole. The catalog data include the serial (source) number, right ascension (B1950.0) and declination (B1950.0), rms uncertainty in 408 MHz position, peak 408 MHz flux density and rms uncertainty, effective envelope attenuation (P_eff) at 408 MHz, difference between the 408 MHz and 1407 MHz positions, rms uncertainty in 1407 MHz position, peak 1407 MHz flux density and uncertainty, envelope attenuation P at 1407 MHz and radio spectral index between 408 MHz and 1407 MHz.
