- ID:
- ivo://CDS.VizieR/J/MNRAS/122/363
- Title:
- Eggen PV photometry in NGC 7492
- Short Name:
- J/MNRAS/122/363
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometry of NGC 7492, a very faint, well resolved cluster, shows that it has a colour-magnitude relation similar in form to that of a typical globular cluster. A well defined but sparsely populated red giant branch is present, along with a horizontal branch, blue stars, and variables. The distance modulus, 17.17, and the distance 27.2kpc., are obtained. The colour excess appears to be negligible. The integrated photographic absolute magnitude is -4.84. The star density in the cluster is unusually low, being approximately 0.06 stars per cubic parsec for stars brighter than +2.5 absolute magnitude. For a description of the PV photometric system, see e.g. <GCPD/31>
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/657/706
- Title:
- EGRET blazar gamma-ray spectrum
- Short Name:
- J/ApJ/657/706
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory (CGRO) discovered gamma-ray emission from more than 67 blazars during its 9yr lifetime. We conducted an exhaustive search of the EGRET archives and selected all the blazars that were observed multiple times and were bright enough to enable a spectral analysis using standard power-law models. The sample consists of 18 flat-spectrum radio quasars (FSRQs), 6 low-frequency peaked BL Lac objects (LBLs) and 2 high-frequency peaked BL Lac objects (HBLs). We do not detect any clear pattern in the variation of spectral index with flux. Some of the blazars do not show any statistical evidence for spectral variability.
4913. EGRET blazars in VIPS
- ID:
- ivo://CDS.VizieR/J/ApJ/671/1355
- Title:
- EGRET blazars in VIPS
- Short Name:
- J/ApJ/671/1355
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine the radio properties of EGRET-detected blazars observed as part of the VLBA Imaging and Polarimetry Survey (VIPS). VIPS has a flux limit roughly an order of magnitude below the MOJAVE survey and most other samples that have been used to study the properties of EGRET blazars. At lower flux levels, radio flux density does not directly correlate with gamma-ray flux density. We do find that the EGRET-detected blazars tend to have higher brightness temperatures, greater core fractions, and possibly larger than average jet opening angles. A weak correlation is also found with jet length and with polarization. All of the well-established trends can be explained by systematically larger Doppler factors in the gamma-ray-loud blazars, consistent with the measurements of higher apparent velocities found in monitoring programs carried out at radio frequencies above 10 GHz.
- ID:
- ivo://CDS.VizieR/J/ApJS/157/324
- Title:
- EGRET high-energy cosmic photons (E>10GeV)
- Short Name:
- J/ApJS/157/324
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During its 9 year lifetime, the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO) detected 1506 cosmic photons with measured energy E>10GeV. Of this number, 187 are found within a 1{deg} of sources that are listed in the Third EGRET Catalog (Cat. <J/ApJS/123/79>) and were included in determining the detection likelihood, flux, and spectra of those sources. In particular, five detected EGRET pulsars are found to have events above 10GeV, and together they account for 37 events. A pulsar not included in the Third EGRET Catalog has two events, both with the same phase and in one peak of the lower energy gamma-ray light curve.
4915. EH Cnc RV light curves
- ID:
- ivo://CDS.VizieR/J/PASP/123/895
- Title:
- EH Cnc RV light curves
- Short Name:
- J/PASP/123/895
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New CCD photometry for the eclipsing binary EH Cnc was made from 2009 to 2011, and five new eclipsing times are presented. Through using the updated Wilson-Devinney code, we first deduced the photometric solution at {chi}^2^=0.9906. The results show that EH Cnc is a W-type contact binary, whose mass ratio and overcontact degree are q=2.51(+/-0.02) and f=27.7%(+/-3.4%) , respectively.
- ID:
- ivo://CDS.VizieR/V/64
- Title:
- Eighth Orbital Elements of Spectroscopic Binaries
- Short Name:
- V/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The complete description of the catalogue, as well as the notes, is to be found in the Publ. Dominion Astrophys. Obs. 17 (1989). The present machine-readable version was transformed from the file provided by A.H. Batten for easier computer readability. Compared to the printed version, please note the following: 1) The four columns No. f(m) m.sin^3(i) a.sin(i) are NOT included in the computer version. No. (running number) is the line number of the main file (from 1 to 1469) f(m) (expressed in Solar Masses) can be computed from the Fortran formula 1.0385E-7 * (1-e*e)**1.5 * K(1)**3 * P a(*)sin i (expressed in km) can be computed from the Fortran formula 13751 * sqrt(1-e*e) * K(*) * P m(*)sin3i (expressed in Solar Masses) can be computed from the Fortran formula 1.0385E-7 * (1-e*e)**1.5 * K(*) * (K(1)+K(2))**2 * P The parameters are K(*) = velocity amplitude of the components, expressed in km/s; P = Period, expressed in days, sometimes in years; e = eccentricity 2) The notes, which make the bulk of the printed catalogue (pages 129-304), are NOT included.
- ID:
- ivo://CDS.VizieR/J/AJ/151/17
- Title:
- Eight transiting light curves of WASP-43b
- Short Name:
- J/AJ/151/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Motivated by the previously reported high orbital decay rate of the planet WASP-43b, we have obtained and present eight newly transiting light curves. Together with other data in the literature, we perform a self-consistent timing analysis with data covering a timescale of 1849 epochs. The results give an orbital decay rate dP/dt=-0.02890795+/-0.00772547s/year, which is one order smaller than previous values. This slow decay rate corresponds to a normally assumed theoretical value of the stellar tidal dissipation factor. In addition, through the frequency analysis, the transit timing variations presented here are unlikely to be periodic, but could be signals of a slow orbital decay.
- ID:
- ivo://CDS.VizieR/J/AJ/132/1256
- Title:
- eim BATC photometry of OJ 287
- Short Name:
- J/AJ/132/1256
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our optical monitoring of the BL Lacertae object OJ 287 during the first half of 2005. The source did not show large-amplitude variations during this period and was in a relatively quiescent state. A possible period of 40 days was derived from its light curves in three BATC wave bands. A bluer-when-brighter chromatism was discovered, which is different from the extremely stable color during the outburst in 1994-1996. The different color behaviors imply different variation mechanisms in the two states. We then revisited the optical data on OJ 287 from the OJ-94 project and also found a probable period of 40 days in its optical variability during the late 1994 outburst. The results suggest that two components contribute to the variability of OJ 287 during its outburst state. The first component is the normal blazar variation. This component has an amplitude similar to that of the quiescent state and also may share a similar periodicity. The second component can be taken as a "low-frequency modulation" to the first component. It may be induced by the interaction of the assumed binary black holes in the center of this object. The 40 day period may be related to the helical structure of the magnetic field at the base of the jet or to the orbital motion close to the central primary black hole.
- ID:
- ivo://CDS.VizieR/J/A+A/623/A123
- Title:
- Einasto parameters for SPARC galaxies
- Short Name:
- J/A+A/623/A123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dark matter-baryon scaling relations in galaxies are important in order to constrain galaxy formation models. Here, we provide a modern quantitative assessment of those relations, by modelling the rotation curves of galaxies from the Spitzer Photometry and Accurate Rotation Curves (SPARC) database with the Einasto dark halo model. We focus in particular on the comparison between the original SPARC parameters, with constant mass-to-light ratios for bulges and disks, and the parameters for which galaxies follow the tightest radial acceleration relation. We show that fits are improved in the second case, and that the pure halo scaling relations also become tighter. We report that the density at the radius where the slope is -2 is strongly anticorrelated to this radius, and to the Einasto index. The latter is close to unity for a large number of galaxies, indicative of large cores. In terms of dark matter-baryon scalings, we focus on relations between the core properties and the extent of the baryonic component, which are relevant to the cusp-core transformation process. We report a positive correlation between the core size of halos with small Einasto index and the stellar disk scale-length, as well as between the averaged dark matter density within 2kpc and the baryon-induced rotational velocity at that radius. This finding is related to the consequence of the radial acceleration relation on the diversity of rotation curve shapes, quantified by the rotational velocity at 2kpc. While a tight radial acceleration relation slightly decreases the observed diversity compared to the original SPARC parameters, the diversity of baryon-induced accelerations at 2kpc is sufficient to induce a large diversity, incompatible with current hydrodynamical simulations of galaxy formation, while maintaining a tight radial acceleration relation.
- ID:
- ivo://CDS.VizieR/J/ApJ/698/2114
- Title:
- Einstein A coeff. for ^12^C_2_D_2_ transitions
- Short Name:
- J/ApJ/698/2114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Two hundred and fifty-one ^12^C_2_D_2_ transitions have been measured in the 0.2-1.6THz region of its nu_5_-nu_4_ difference band and 202 of them were observed for the first time. The accuracy of these measurements is estimated to be ranging from 50kHz to 100kHz. The ^12^C_2_D_2_ molecules were generated under room temperature by passing 120-150mTorr D_2_O vapor through calcium carbide (CaC_2_) powder. A multistate analysis was carried out for the bending vibrational modes nu_4_ and nu_5_ of ^12^C_2_D_2_, which includes the lines observed in this work and prior microwave, far-infrared and infrared data on the pure bending levels. Significantly improved molecular parameters were obtained for ^12^C_2_D_2_ by adding the new measurements to the old data set, which had only 10 lines with microwave measurement precision. New frequency and intensity predictions have been made based on the obtained molecular parameters. The more precise measurements and new predictions reported here will support the analyses of astronomical observations by the future high-resolution spectroscopy telescopes such as Herschel, SOFIA, and ALMA, which will work in the terahertz spectral region.