- ID:
- ivo://CDS.VizieR/J/A+A/529/A128
- Title:
- Velocity catalog of A545 galaxies
- Short Name:
- J/A+A/529/A128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The mechanisms giving rise to diffuse radio emission in galaxy clusters, and in particular their connection with cluster mergers, are still debated. We seek to explore the internal dynamics of the cluster Abell 545, which has been shown to host a radio halo. Abell 545 is also peculiar for hosting in its center a very bright, red, diffuse intracluster light due to an old, presumably metal-rich stellar population, so bright to be named as "star pile". Our analysis is mainly based on redshift data for 110 galaxies acquired at the Telescopio Nazionale Galileo. We identify 95 cluster members and analyze the cluster internal dynamics by combining galaxy velocities and positions. We also use both multiband photometric data acquired at the Isaac Newton Telescope and X-ray data from the XMM-Newton Science Archive.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/529/A134
- Title:
- Velocity curve of {alpha} Arietis
- Short Name:
- J/A+A/529/A134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To search for extra-solar planets around intermediate mass stars, we are conducting a precise RV survey around K-giants. We present high-accuracy RV measurements of alpha Ari from November 2003 to February 2010. This star belongs to our sample of 55 K-giants studied for extra-solar planet and pulsation searches using the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) attached to the 1.8-m telescope at Bohyunsan Optical Astronomy Observatory (BOAO) in Korea. We find a planetary companion with a long-period and low-amplitude radial velocity (RV) variations in oscillating K2 III star alpha Ari (HD 12929). We do not find the correlation between RV variations and chromospheric activity indicators (CaII H & K region, H{alpha} line). The bisector analysis also shows that bisector velocity span (BVS) does not show any obvious correlation with RV variation but has periodic component that may be attributed to the rotation of the star. If the RV variation is indeed caused by a planetary companion, an orbital solution with a period of P=381-days, a semi-amplitude of K=41m/s, and an eccentricity of e=0.25 fits the data best. Assuming a possible stellar mass of M_star_=1.5M_{sun}_, we estimate the minimum mass for the planetary companion of m_2_sini=1.8M_{Jupiter}_ with an orbital semi-major axis of 1.2AU. Our finding of a likely exoplanet in alpha Ari gives a support to search for extra-solar planets around giant stars with multi-periodic oscillations.
- ID:
- ivo://CDS.VizieR/J/A+A/578/A64
- Title:
- Velocity curve of {tau} Boo A
- Short Name:
- J/A+A/578/A64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed the tau Boo system with the HARPS-N spectrograph in order to test a new observational strategy aimed to jointly study asteroseismology, the planetary orbit and star-planet magnetic interaction. We collected high-cadence observations on 11 nearly consecutive nights, and for each night averaged the raw FITS files using dedicated software in order to obtain high S/N spectra to study the variation of the CaII H&K lines and radial velocity values free from stellar oscillations without losing this latter information. Specific software was written to build a new custom mask used to refine the RV determination with the HARPS-N pipeline and to perform the spectroscopic analysis. We updated the planetary ephemeris and proved the acceleration due to the stellar binary companion. The study of stellar activity variation suggests the presence of an high-latitude plage during the time span of our observations. The correlation between the chromospheric activity and the planetary orbital phase remains unclear. Solar-like oscillations are detected in the radial velocity time series: we estimate asteroseismic quantities finding good agreement with theoretical predictions. With the stellar model built we find for tau Boo an age of 0.9+/-0.5Gyr, and could further constrain the value of the stellar mass to 1.38+/-0.05M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/566/A67
- Title:
- Velocity curves of {beta}Cnc, {mu}Leo and {beta}UMi
- Short Name:
- J/A+A/566/A67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To investigate the low-amplitude and long-period variations in evolved stars with a precise radial velocity (RV) survey. The high-resolution, the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) was used from 2003 to 2013 for an RV survey of giant stars as part of the exoplanet search program at Bohyunsan Optical Astronomy Observatory (BOAO). We report the detection of three new planetary companions orbiting the K giants beta Cnc, mu Leo, and beta UMi. The planetary nature of the RV variations is supported by analyses of ancillary data. The HIPPARCOS photometry shows no variations with periods close to those in RV variations and there is no strong correlation between the bisector velocity span (BVS) and the RVs for each star. Furthermore, the stars show weak or no core reversal in Ca II H lines indicating that they are inactive stars. The companion to beta Cnc has a minimum mass of 7.8M_Jup_ in a 605-day orbit with an eccentricity of 0.08. mu Leo is orbited by a companion of minimum mass of 2.4M_Jup_ having a period of 357-days, and an eccentricity of 0.09. beta UMi is a known barium star and is suspected of harbouring a white dwarf or substellar mass companion. Its companion has a minimum mass of 6.1M_Jup_, a period of 522-days, and an eccentricity e=0.19.
- ID:
- ivo://CDS.VizieR/J/AJ/146/107
- Title:
- Velocity curves of 10 cataclysmic binaries
- Short Name:
- J/AJ/146/107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on ground-based optical observations of 10 cataclysmic binaries that were discovered through their X-ray emission. Time-resolved radial velocity spectroscopy yields unambiguous orbital periods for eight objects and ambiguous results for the remaining two. The orbital periods range from 87 minutes to 9.38 hr. We also obtained time-series optical photometry for six targets, four of which have coherent pulsations. These periods are 1218s for 1RXSJ045707.4+452751, 628s for AXJ1740.2-2903, 477s for AXJ1853.3-0128, and 935s for IGRJ19267+1325. A total of seven of the sources have coherent oscillations in X-rays or optical, indicating that they are intermediate polars (DQ Herculis stars). Time-resolved spectroscopy of one object, SwiftJ2218.4+1925, shows that it is an AM Herculis star, or polar, and IGRJ19552+0044 may also be in that class. For another object, SwiftJ0746.2-1611, we find an orbital period of 9.384 hr and detect the spectrum of the secondary star. The secondary's spectral contribution implies a distance of 900 (+190, -150)pc, where the error bars are estimated using a Monte Carlo technique to account for correlated uncertainties.
22596. Velocity curves of HD 40307
- ID:
- ivo://CDS.VizieR/J/A+A/493/639
- Title:
- Velocity curves of HD 40307
- Short Name:
- J/A+A/493/639
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the detection of a planetary system with three Super-Earths orbiting HD 40307. HD 40307 is a K2 V metal-deficient star at a distance of only 13 parsec, which is part of the HARPS GTO high-precision planet-search programme. The three planets on circular orbits have very low minimum masses of 4.2, 6.9, and 9.2 Earth masses and periods of 4.3, 9.6, and 20.5 days, respectively.
- ID:
- ivo://CDS.VizieR/J/A+A/619/A2
- Title:
- Velocity curves of 3 open cluster stars
- Short Name:
- J/A+A/619/A2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The aim of this work is to search for planets around intermediate-mass stars in open clusters by using data from an extensive survey with more than 15 years of observations. We obtain high-precision radial velocities (RV) with the HARPS spectrograph for a sample of 142 giant stars in 17 open clusters. We fit Keplerian orbits when a significant periodic signal is detected. We also study the variation of stellar activity indicators and line-profile variations to discard stellar-induced signals. We present the discovery of a periodic RV signal compatible with the presence of a planet candidate in the 1.15Gyr open cluster IC4651 orbiting the 2.06M_{sun}_ star No. 9122. If confirmed, the planet candidate would have a minimum mass of 7.2M_J_ and a period of 747 days. However, we also find that the FWHM of the CCF varies with a period close to the RV, casting doubts on the planetary nature of the signal. We also provide refined parameters for the previously discovered planet around NGC2423 No. 3 but show evidence that the BIS of the CCF is correlated with the RV during some of the observing periods. This fact advises us that this might not be a real planet and that the RV variations could be caused by stellar activity and/or pulsations. Finally, we show that the previously reported signal by a brown dwarf around NGC4349 No. 127 is presumably produced by stellar activity modulation. The long-term monitoring of several red giants in open clusters has allowed us to find periodic RV variations in several stars. However, we also show that the follow-up of this kind of stars should last more than one orbital period to detect long-term signals of stellar origin. This work warns that although it is possible to detect planets around red giants, large-amplitude, long-period RV modulations do exist in such stars that can mimic the presence of an orbiting planetary body. Therefore, we need to better understand how such RV modulations behave as stars evolve along the Red Giant Branch and perform a detailed study of all the possible stellar-induced signals (e.g. spots, pulsations, granulation) to comprehend the origin of RV variations.
- ID:
- ivo://CDS.VizieR/J/A+A/537/A117
- Title:
- Velocity curves of SW CMa and HW CMa
- Short Name:
- J/A+A/537/A117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate physical properties of eclipsing stars provide important constraints on models of stellar structure and evolution, especially when combined with spectroscopic information on their chemical composition. Empirical calibrations of the data also lead to accurate mass and radius estimates for exoplanet host stars. Finally, accurate data for unusual stellar subtypes, such as Am stars, also help to unravel the cause(s) of their peculiarities. We aim to determine the masses, radii, effective temperatures, detailed chemical composition and rotational speeds for the Am-type eclipsing binaries SWCMa (A4-5m) and HWCMa (A6m) and compare them with similar normal stars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/224/453
- Title:
- Velocity data of rich clusters
- Short Name:
- J/MNRAS/224/453
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present redshifts and stellar velocity dispersions for about 40 galaxies in each of 14 rich clusters from the southern cluster survey of Abell & Corwin (1983, Early Evolution of the Universe and Its Present Structure, p.179, Eds. Abell & Chincarini, Reidel, Dordrecht, Holland). The clusters cover a wide range of richnesses and Abell and Bautz-Morgan types, our aim being to compile a large, homogeneous database for examining and comparing dynamical phenomena and morphological properties. Further papers will present photometry for the clusters and an analysis of the database.
22600. Velocity dispersion in AGN
- ID:
- ivo://CDS.VizieR/J/ApJ/585/647
- Title:
- Velocity dispersion in AGN
- Short Name:
- J/ApJ/585/647
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It has been proposed that the width of the narrow [O III] {lambda}5007 emission line can be used as a surrogate for the stellar velocity dispersion in active galaxies. This proposition is tested using the Sloan Digital Sky Survey (SDSS) Early Data Release (EDR) spectra of 107 low-redshift radio-quiet QSOs and Seyfert 1 galaxies by investigating the correlation between black hole mass, as determined from H{beta} FWHM and optical luminosity, and [O III] FWHM. The correlation is real, but the scatter is large. Without additional information or selection criteria, the [O III] width can predict the black hole mass to a factor of 5.
