- ID:
- ivo://CDS.VizieR/J/ApJ/876/102
- Title:
- Reverberation mapping of the Seyfert Zw I 1
- Short Name:
- J/ApJ/876/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report results of the first reverberation mapping campaign of I Zwicky 1 during 2014-2016, which showed unambiguous reverberations of the broad H{beta} line emission in the varying optical continuum. From analysis using several methods, we obtain a reverberation lag of {tau}_H{beta}_=37.2_-4.9_^+4.5^days. Taking a virial factor of f_BLR_=1, we find a black hole mass of M_{bullet}_=9.30_-1.38_^+1.26^x10^6^M_{sun}_ from the mean spectra. The accretion rate is estimated to be 203.9_-65.8_^+61.0^L_Edd_c^-2^, suggesting a super-Eddington accretor, where LEdd is the Eddington luminosity and c is the speed of light. By decomposing Hubble Space Telescope images, we find that the stellar mass of the bulge of its host galaxy is log(M_bulge_/M_{sun}_)=10.92+/-0.07. This leads to a black hole to bulge mass ratio of ~10^-4^, which is significantly smaller than that of classical bulges and elliptical galaxies. After subtracting the host contamination from the observed luminosity, we find that I Zw 1 follows the empirical R_BLR_{propto}L_5100_^1/2^ relation.
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- ID:
- ivo://CDS.VizieR/J/AJ/142/61
- Title:
- RGB stars in LMC outer disk
- Short Name:
- J/AJ/142/61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The outer disk of the Large Magellanic Cloud (LMC) is studied in order to unveil clues about its formation and evolution. Complementing our previous studies in innermost fields (3kpc<~R<~7kpc), we obtained deep color-magnitude diagrams in six fields with galactocentric distances from 5.2kpc to 9.2kpc and different azimuths. The comparison with isochrones shows that while the oldest population is approximately coeval in all fields, the age of the youngest populations increases with increasing radius. This agrees with the results obtained in the innermost fields. Low-resolution spectroscopy in the infrared CaII triplet region has been obtained for about 150 stars near the tip of the red giant branch in the same fields. Radial velocities and stellar metallicities have been obtained from these spectra. The metallicity distribution of each field has been analyzed together with those previously studied.
- ID:
- ivo://CDS.VizieR/J/MNRAS/430/1125
- Title:
- RMS survey: NIR spectroscopy of massive YSOs
- Short Name:
- J/MNRAS/430/1125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared H- and K-band spectra are presented for 247 objects, selected from the Red MSX Source (RMS) survey as potential young stellar objects (YSOs). 195 (~80%) of the targets are YSOs, of which 131 are massive YSOs (L_BOL_>5x10^3^L_{sun}_, M>8M_{sun}_). This is the largest spectroscopic study of massive YSOs to date, providing a valuable resource for the study of massive star formation. In this paper, we present our exploratory analysis of the data. The YSOs observed have a wide range of embeddedness (2.7<A_V_<114), demonstrating that this study covers minimally obscured objects right through to very red, dusty sources. Almost all YSOs show some evidence for emission lines, though there is a wide variety of observed properties. The most commonly detected lines are Br{gamma}, H_2_, fluorescent FeII, CO bandhead, [FeII] and HeI 2-1 1S-1P, in order of frequency of occurrence. In total, ~40% of the YSOs display either fluorescent FeII 1.6878{mu}m or CO bandhead emission (or both), indicative of a circumstellar disc; however, no correlation of the strength of these lines with bolometric luminosity was found. We also find that ~60% of the sources exhibit [FeII] or H_2_ emission, indicating the presence of an outflow. Three quarters of all sources have Br{gamma} in emission. A good correlation with bolometric luminosity was observed for both the Br{gamma} and H_2_ emission line strengths, covering 1<L_BOL_<3.5x10^5^L_{sun}_. This suggests that the emission mechanism for these lines is the same for low-, intermediate- and high-mass YSOs, i.e. high-mass YSOs appear to resemble scaled-up versions of low-mass YSOs.
- ID:
- ivo://CDS.VizieR/J/ApJS/247/53
- Title:
- ROGUE. I. SDSS galaxies with FIRST
- Short Name:
- J/ApJS/247/53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the catalog of Radio sources associated with Optical Galaxies and having Unresolved or Extended morphologies I (ROGUE I), consisting of 32616 spectroscopically selected galaxies. It is the largest handmade catalog of this kind, obtained by cross-matching galaxies from the Sloan Digital Sky Survey (SDSS) Data Release 7 and radio sources from both the First Images of Radio Sky at Twenty Centimetre (FIRST) survey and the NRAO Very Large Array Sky Survey, without imposing a limit on the radio flux densities. The catalog provides a visual classification of radio and optical morphologies of galaxies presenting a FIRST core within 3" of the optical position. The radio morphological classification is performed by examining the radio-optical overlays of linear sizes equal to 1Mpc at the source distance, while the 120" image snapshots from the SDSS database are used for optical classification. The results of our search are as follows: (i) single-component unresolved and elongated radio sources constitute the major group in the ROGUE I catalog (~90%), and ~8% exhibit extended morphologies; (ii) samples of 269, 730, and 115 Fanaroff-Riley (FR) type I, II, and hybrid galaxies, respectively, are presented; (iii) we report 55 newly discovered giant/possible giant, 16 double-double, 9 X-shaped, and 25 Z-shaped radio sources; (iv) on the optical front, most galaxies have elliptical morphologies (~62%) while spirals form the second major category (~17%) followed by distorted (~12%) and lenticular (~7%) morphologies; and (v) division between the FR I and the FR II sources in the radio-optical luminosity plane is blurred, in tune with recent studies.
- ID:
- ivo://CDS.VizieR/J/AJ/159/145
- Title:
- RVs and opt. photometry of the host star TOI-677
- Short Name:
- J/AJ/159/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of TOI-677b, first identified as a candidate in light curves obtained within Sectors 9 and 10 of the Transiting Exoplanet Survey Satellite (TESS) mission and confirmed with radial velocities. TOI-677b has a mass of M_p_=1.236_-0.067_^+0.069^M_J_, a radius of R_P_=1.170{+/-}0.03R_J_, and orbits its bright host star (V=9.8mag) with an orbital period of 11.23660{+/-}0.00011d, on an eccentric orbit with e=0.435{+/-}0.024. The host star has a mass of M_*_=1.181{+/-}0.058M_{sun}_, a radius of R_*_=1.28_-0.03_^+0.03^R_{sun}_, an age of 2.92_-0.73_^+0.80^Gyr and solar metallicity, properties consistent with a main-sequence late-F star with T_eff_=6295{+/-}77K. We find evidence in the radial velocity measurements of a secondary long-term signal, which could be due to an outer companion. The TOI-677b system is a well-suited target for Rossiter-Mclaughlin observations that can constrain migration mechanisms of close-in giant planets.
- ID:
- ivo://CDS.VizieR/J/AJ/160/222
- Title:
- RVs and RI-photometry of HATS-37 and HATS-38
- Short Name:
- J/AJ/160/222
- Date:
- 09 Mar 2022 22:00:00
- Publisher:
- CDS
- Description:
- We report the discovery of two transiting Neptunes by the HATSouth survey. The planet HATS-37Ab has a mass of 0.099{+/-}0.042M_Jup_ (31.5{+/-}13.4M{Earth}) and a radius of 0.606{+/-}0.016R_Jup_, and is on a P=4.3315day orbit around a V=12.266{+/-}0.030mag, 0.843_-0.012_^+0.017^M{odot} star with a radius of 0.877_-0.012_^+0.019^R{odot}. We also present evidence that the star HATS-37A has an unresolved stellar companion HATS-37B, with a photometrically estimated mass of 0.654{+/-}0.033M{odot}. The planet HATS-38b has a mass of 0.074{+/-}0.011M_Jup_ (23.5{+/-}3.5M{Earth}) and a radius of 0.614{+/-}0.017R_Jup_, and is on a P=4.3750day orbit around a V=12.411{+/-}0.030mag, 0.890_-0.012_^+0.016^M{odot} star with a radius of 1.105{+/-}0.016 R{odot}. Both systems appear to be old, with isochrone-based ages of 11.46_-1.45_^+0.79^Gyr, and 11.89{+/-}0.60Gyr, respectively. Both HATS-37Ab and HATS-38b lie in the Neptune desert and are thus examples of a population with a low occurrence rate. They are also among the lowest-mass planets found from ground-based wide-field surveys to date.
- ID:
- ivo://CDS.VizieR/J/ApJ/877/44
- Title:
- RV variability in SDSS dwarf carbon stars
- Short Name:
- J/ApJ/877/44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dwarf carbon (dC) stars (main-sequence stars showing carbon molecular bands) were initially thought to be an oxymoron because only asymptotic giant branch (AGB) stars dredge carbon into their atmospheres. Mass transfer from a former AGB companion that has since faded to a white dwarf seems the most likely explanation. Indeed, a few types of giants known to show anomalous abundances- notably, the CH, Ba and CEMP-s stars-are known to have a high binary frequency. The dC stars may be the enhanced-abundance progenitors of most, if not all of these systems, but this requires demonstrating a high binary frequency for dCs. Here, for a sample of 240 dC stars targeted for repeat spectroscopy by the SDSS-IV's Time Domain Spectroscopic Survey, we analyze radial velocity (RV) variability to constrain the binary frequency and orbital properties. A handful of dC systems show large velocity variability (>100km/s). We compare the dCs to a control sample with a similar distribution of magnitude, color, proper motion, and parallax. Using Markov chain Monte Carlo methods, we use the measured {Delta}RV distribution to estimate the binary fraction and the separation distribution assuming both a unimodal and bimodal distribution. We find the dC stars have an enhanced binary fraction of 95%, consistent with them being products of mass transfer. These models result in mean separations of less than 1 au corresponding to periods on the order of 1 yr. Our results support the conclusion that dC stars form from close binary systems via mass transfer.
- ID:
- ivo://CDS.VizieR/J/ApJ/804/7
- Title:
- SaMOSA: optical spectroscopy of 7 Fermi blazars
- Short Name:
- J/ApJ/804/7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multi-epoch optical spectroscopy of seven southern Fermi-monitored blazars from 2008 to 2013 using the Small and Medium Aperture Research Telescope System (SMARTS), with supplemental spectroscopy and polarization data from the Steward Observatory. We find that the emission lines are much less variable than the continuum; four of seven blazars had no detectable emission line variability over the 5 yr observation period. This is consistent with photoionization primarily by an accretion disk, allowing us to use the lines as a probe of disk activity. Comparing optical emission line flux with Fermi {gamma}-ray flux and optical polarized flux, we investigate whether relativistic jet variability is related to the accretion flow. In general, we see no such dependence, suggesting that the jet variability is likely caused by internal processes like turbulence or shock acceleration rather than a variable accretion rate. However, three sources showed statistically significant emission line flares in close temporal proximity to very large Fermi {gamma}-ray flares. While we do not have sufficient emission line data to quantitatively assess their correlation with the {gamma}-ray flux, it appears that in some cases the jet might provide additional photoionizing flux to the broad-line region (BLR), which implies that some {gamma}-rays are produced within the BLR, at least for these large flares.
- ID:
- ivo://CDS.VizieR/J/ApJ/886/93
- Title:
- SAMP. III. Opt. LCs and spectra of two AGNs
- Short Name:
- J/ApJ/886/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Active galactic nuclei (AGNs) show a correlation between the size of the broad line region and the monochromatic continuum luminosity at 5100{AA}, allowing black hole mass estimation based on single-epoch spectra. However, the validity of the correlation is yet to be clearly tested for high-luminosity AGNs. We present the first reverberation mapping results of the Seoul National University AGN Monitoring Project (SAMP), which is designed to focus on luminous AGNs for probing the high end of the size-luminosity relation. We report time lag measurements of two AGNs, namely, 2MASSJ10261389+5237510 and SDSSJ161911.24+501109.2, using the light curves obtained over an ~1000d period with an average cadence of 10 and 20d, respectively, for photometry and spectroscopy monitoring. Based on a cross-correlation analysis and H{beta} line width measurements, we determine the H{beta} lag as 41.8_-6.0_^+4.9^ and 52.6_-14.7_^+17.6^ days in the observed frame, and black hole mass as 3.65_-0.57_^+0.49^x10^7^M_{sun}_ and 23.02_-6.56_^+7.81^x10^7^M_{sun}_, respectively, for 2MASS J1026 and SDSS J1619.
- ID:
- ivo://CDS.VizieR/J/AJ/139/1857
- Title:
- Sample of major galaxy pairs at z=0.08-0.38
- Short Name:
- J/AJ/139/1857
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measure the strength, frequency, and timescale of tidally triggered star formation at redshift z=0.08-0.38 in a spectroscopically complete sample of galaxy pairs drawn from the magnitude-limited redshift survey of 9825 Smithsonian Hectospec Lensing Survey galaxies with R<20.3. To examine the evidence for tidal triggering, we identify a volume-limited sample of major (|{Delta}M_R_|<1.75, corresponding to mass ratio >1/5) pair galaxies with M_R_<-20.8 in the redshift range z=0.08-0.31.