- ID:
- ivo://CDS.VizieR/J/PAZh/25/893
- Title:
- Optical outbursts of the blazar 3C 345
- Short Name:
- J/PAZh/25/893
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photographic UBV photometry of the blazar 3C 345 that were made during 79 nights in 1971-1974 and 1983-1984 as a part of the Petersburg Quasar Monitoring Program (PQMP) carried out at the Astronomical Institute of the St.-Petersburg University. These data were previously published by piecemeal (references are presented in Section 4). Now after partial revision these data are united in Table 1 that presents nightly averaged UBV magnitudes together with its rms errors (see Section 4 of the paper for the details). These data were used for the comparison of the spectral indices of the emission in the "fast" (time scales of nearly 10-20 days) and "slow" (time scales of nearly 1 yeas) outbursts in 3C 345.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/150/67
- Title:
- Optical photometry for 1ES 1959+650
- Short Name:
- J/AJ/150/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the 1.56m telescope at Shanghai Observatory, China, we present the photometric results of 1ES 1959+650, which cover from 2006 June 11 to 2014 July 31. The maximum variabilities are {Delta}m_V|max_=1.74+/-0.02mag in the V band, {Delta}m_R|max_=0.97+/-0.02mag in the R band, and {Delta}m_I/max_=1.15+/-0.03mag in the I band. During the monitoring period, we obtain intraday variabilities on 2009 September 2 (JD2455077) and 2009 September 3 (JD2455078). On 2009 September 2, the intraday variabilities are {Delta}m_V_=0.36+/-0.08mag within 1.56hr, {Delta}m_R_=0.21+/-0.04mag within 23minutes, and {Delta}m_I_=0.53+/-0.03mag within 45minutes. On 2009 September 3, the intraday variabilities are {Delta}m_V_=0.40+/-0.10mag within 27minutes, {Delta}m_R_=0.48+/-0.04mag within 3.24hr, and {Delta}m_I_=0.68+/-0.06mag within 3.72hr. The two intraday variabilities occur in 24hr, which may occur in the same variable phase. Other results show that (1) no quasi-periodicity is found in the long-term light curve and (2) the correlations between the brightness and the spectrum show obvious anti-correlation, {alpha}=-(0.18+/-0.02)F_V_+(2.33+/-0.12), with the correlation coefficient r=-0.74 and the chance probability p<0.01%.
- ID:
- ivo://CDS.VizieR/J/ApJ/569/23
- Title:
- Optical polarisation of 2MASS QSOs
- Short Name:
- J/ApJ/569/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Optical broadband polarimetry is presented for near-infrared color-selected active galactic nuclei (AGNs) classified as quasi-stellar objects (QSOs) based on their Ks-band luminosity. More than 10% of a sample of 70 QSOs discovered in the Two Micron All Sky Survey (2MASS, Cat. <B/2mass>) with J-Ks>2 and M_Ks_<-23 show high broadband linear polarization (P>3%), and values range to a maximum of P~11%. High polarization tends to be associated with the most luminous objects at Ks and with QSOs having the highest near-IR to optical flux ratios. The 2MASS QSO sample includes objects possessing a wide range of optical spectral types. High polarization is seen in two of 22 broad emission-line (type 1) objects, but ~1/4 of the QSOs of intermediate spectral type (type 1.5-1.9) are highly polarized. None of the nine QSOs classified as type 2 exhibit P>3%.
- ID:
- ivo://CDS.VizieR/J/A+AS/142/451
- Title:
- Optical Polarization of 47 QSOs
- Short Name:
- J/A+AS/142/451
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New broad-band linear polarization measurements are presented for a sample of 47 QSOs which includes 27 broad absorption line QSOs and 2 gravitational lens candidates.
- ID:
- ivo://CDS.VizieR/J/A+A/433/757
- Title:
- Optical polarization of 203 QSOs
- Short Name:
- J/A+A/433/757
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This Table contains linear polarization measurements (mainly in the V band) of 203 QSOs. First time measurements have been obtained for 184 objects. Among them 109 known radio emitters, 42 BAL and 1 gravitationally lensed QSO.
- ID:
- ivo://CDS.VizieR/J/AJ/125/2728
- Title:
- Optical positions of ICRF sources
- Short Name:
- J/AJ/125/2728
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New optical positions on the 30mas precision level have been obtained for 172 extragalactic International Celestial Reference Frame (ICRF) sources mainly in the range -30{deg}<=DE<=+25{deg}. Results are presented from a pilot investigation including four Cerro Tololo (CTIO) 0.9m runs (1999-2001). Reference stars in the R~10-16.5mag used. Systematic errors have been investigated, and a field distortion pattern based on the residuals has been removed. The errors of the fainter stars in the CTIO data were assessed by evaluating an auxiliary set of CCD observations of common ICRF sources, taken at the 1.60m Cassegrain telescope of the Laboratorio Nacional de Astrofisica, Brazil. A significant improvement in the optical positions was achieved over a previous determination of source positions. The mean optical positions are compared with the ICRF radio positions. The overall optical minus radio offsets are -6 and -15mas for right ascension and declination, respectively. The formal internal error of these mean offsets is ~2.3mas. his indicates a possible systematic error in the UCAC declinations of 10 to 15mas. Both the optical counterpart observations and the optical reference stars are observed about 9 yr after the Hipparcos mean epoch, and our results set an upper limit for a possible Hipparcos system rotation with respect to the International Celestial Reference System for the z-axis of about 0.7mas/yr.
- ID:
- ivo://CDS.VizieR/J/ApJ/895/114
- Title:
- Optical, radio and X-ray properties for 113 QSOs
- Short Name:
- J/ApJ/895/114
- Date:
- 16 Mar 2022 00:19:12
- Publisher:
- CDS
- Description:
- We investigate whether the correlation between the hard X-ray photon index ({Gamma}) and accretion rate for super-Eddington accreting quasars is different from that for sub-Eddington accreting quasars. We construct a sample of 113 bright quasars from the Sloan Digital Sky Survey Data Release 14 quasar catalog, with 38 quasars as the super-Eddington subsample and 75 quasars as the sub-Eddington subsample. We derive black hole masses using a simple-epoch virial mass formula based on the H{beta} lines, and we use the standard thin disk model to derive the dimensionless accretion rates (M) for our sample. The X-ray data for these quasars are collected from the Chandra and XMM-Newton archives. We fit the hard X-ray spectra using a single power-law model to obtain {Gamma} values. We find a statistically significant (R_S_=0.43, p=7.75x10^-3^) correlation between {Gamma} and M for the super-Eddington subsample. The {Gamma}-M correlation for the sub-Eddington subsample is also significant, but weaker (R_S_=0.30, p=9.98x10^-3^). Linear regression analysis shows that {Gamma}=(0.34{+/-}0.11)log(M)+(1.71{+/-}0.17) and {Gamma}=(0.09{+/-}0.04)log(M)+(1.93{+/-}0.04) for the super- and sub-Eddington subsamples, respectively. The {Gamma}-M correlations of the two subsamples are different, suggesting different disk-corona connections in these two types of systems. We propose one qualitative explanation of the steeper {Gamma}-M correlation in the super-Eddington regime that involves larger seed photon fluxes received by the compact coronae from the thick disks in super-Eddington accreting quasars.
- ID:
- ivo://CDS.VizieR/J/ApJS/145/199
- Title:
- Optical spectroscopic atlas of low-redshift AGN
- Short Name:
- J/ApJS/145/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectral atlas of the H{beta} region for 215 type 1 AGNs (luminous Seyfert 1/radio galaxy nuclei and low-z quasars) up to z~0.8. Line profiles and measures were derived from the database of intermediate resolution spectra (R>~1000) with average continuum level S/N ratio ~30. Parameters including rest frame equivalent width and FWHM are provided for the FeII_opt_ blend at {lambda}4570, H{beta}, HeII {lambda}4686, and the [OIII] {lambda}{lambda}4959, 5007 emission lines. We extract clean broad component H{beta} profiles and provide wavelength measurements at 0, 1/4, 1/2, 3/4, and 0.9 peak intensity levels in order to permit a quantitative definition of the H{beta} broad component for statistical studies. We also discuss sources of uncertainty, selection effects, and biases in our sample. The data are especially important for tests of the eigenvector 1 parameter space occupation and correlation. We show that the I Zw 1 template FeII_opt_ spectrum reproduces well the observed FeII_opt_ emission for a wide range of line width and strength. A detailed analysis of the data within the eigenvector 1 context is deferred to a companion paper.
- ID:
- ivo://CDS.VizieR/J/other/RMxAA/48.9
- Title:
- Optical spectroscopic atlas of MOJAVE AGNs
- Short Name:
- J/other/RMxAA/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an optical spectroscopic atlas for 123 core-dominated radio-loud active galactic nuclei with relativistic jets, drawn from the MOJAVE/2cm (Monitoring of Jets in AGN with VLBA Experiments) sample at 15GHz. It is the first time that spectroscopic and photometric parameters for a large sample of such type of AGN are presented.
- ID:
- ivo://CDS.VizieR/J/ApJ/748/49
- Title:
- Optical spectroscopy of 1LAC broad-line blazars
- Short Name:
- J/ApJ/748/49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on optical spectroscopy of 165 flat spectrum radio quasars (FSRQs) in the Fermi 1LAC sample, which have helped allow a nearly complete study of this population. Fermi FSRQs show significant evidence for non-thermal emission even in the optical; the degree depends on the {gamma}-ray hardness. They also have smaller virial estimates of hole mass than the optical quasar sample. This appears to be largely due to a preferred (axial) view of the {gamma}-ray FSRQ and non-isotropic (H/R ~ 0.4) distribution of broad-line velocities. Even after correction for this bias, the Fermi FSRQs show higher mean Eddington ratios than the optical population. A comparison of optical spectral properties with Owens Valley Radio Observatory radio flare activity shows no strong correlation.
