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1331. Planets and their host stars with Gaia parallaxes
ID:
ivo://CDS.VizieR/J/AJ/153/136
Title:
Planets and their host stars with Gaia parallaxes
Short Name:
J/AJ/153/136
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present empirical measurements of the radii of 116 stars that host transiting planets. These radii are determined using only direct observables - the bolometric flux at Earth, the effective temperature, and the parallax provided by the Gaia first data release - and thus are virtually model independent, with extinction being the only free parameter. We also determine each star's mass using our newly determined radius and the stellar density, a virtually model independent quantity itself from previously published transit analyses. These stellar radii and masses are in turn used to redetermine the transiting-planet radii and masses, again using only direct observables. The median uncertainties on the stellar radii and masses are 8% and 30%, respectively, and the resulting uncertainties on the planet radii and masses are 9% and 22%, respectively. These accuracies are generally larger than previously published model-dependent precisions of 5% and 6% on the planet radii and masses, respectively, but the newly determined values are purely empirical. We additionally report radii for 242 stars hosting radial-velocity (non-transiting) planets, with a median achieved accuracy of ~2%. Using our empirical stellar masses we verify that the majority of putative "retired A stars" in the sample are indeed more massive than ~1.2 M_{sun}_. Most importantly, the bolometric fluxes and angular radii reported here for a total of 498 planet host stars-with median accuracies of 1.7% and 1.8%, respectively-serve as a fundamental data set to permit the re-determination of transiting-planet radii and masses with the Gaia second data release to ~3% and ~5% accuracy, better than currently published precisions, and determined in an entirely empirical fashion.
1332. Planets orbiting metal-poor dwarfs. II.
ID:
ivo://CDS.VizieR/J/ApJ/697/544
Title:
Planets orbiting metal-poor dwarfs. II.
Short Name:
J/ApJ/697/544
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of three years of precision radial velocity (RV) measurements of 160 metal-poor stars observed with HIRES on the Keck 1 telescope. We report on variability and long-term velocity trends for each star in our sample. We identify several long-term, low-amplitude RV variables worthy of followup with direct imaging techniques. We place lower limits on the detectable companion mass as a function of orbital period. Our survey would have detected, with a 99.5% confidence level, over 95% of all companions on low-eccentricity orbits with velocity semiamplitude K>~100m/s, or M_p_sini>~3.0M_J_(P/yr)^(1/3)^, for orbital periods P<~3yr. None of the stars in our sample exhibits RV variations compatible with the presence of Jovian planets with periods shorter than the survey duration.
1333. PMAS Integral-field SN hosts COmpilation (PISCO)
ID:
ivo://CDS.VizieR/J/ApJ/855/107
Title:
PMAS Integral-field SN hosts COmpilation (PISCO)
Short Name:
J/ApJ/855/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the PMAS/PPak Integral-field Supernova hosts COmpilation (PISCO), which comprises integral field spectroscopy (IFS) of 232 supernova (SN) host galaxies that hosted 272 SNe, observed over several semesters with the 3.5m telescope at the Calar Alto Observatory (CAHA). PISCO is the largest collection of SN host galaxies observed with wide-field IFS, totaling 466347 individual spectra covering a typical spatial resolution of ~380pc. Focused studies regarding specific SN Ia-related topics will be published elsewhere; this paper aims to present the properties of the SN environments, using stellar population (SP) synthesis, and the gas-phase interstellar medium, providing additional results separating stripped-envelope SNe into their subtypes. With 11270 HII regions detected in all galaxies, we present for the first time a statistical analysis of HII regions, which puts HII regions that have hosted SNe in context with all other star-forming clumps within their galaxies. SNe Ic are associated with environments that are more metal-rich and have higher EW(H{alpha}) and higher star formation rate within their host galaxies than the mean of all HII regions detected within each host. This in contrast to SNe IIb, which occur in environments that are very different compared to other core-collapse SNe types. We find two clear components of young and old SPs at SNe IIn locations. We find that SNe II fast decliners tend to explode at locations where the {Sigma}SFR is more intense. Finally, we outline how a future dedicated IFS survey of galaxies in parallel to an untargeted SN search would overcome the biases in current environmental studies.
1334. PM2GC mass-limited sample surface photometry
ID:
ivo://CDS.VizieR/J/ApJ/762/77
Title:
PM2GC mass-limited sample surface photometry
Short Name:
J/ApJ/762/77
Date:
21 Oct 2021
Publisher:
CDS
Description:
We search for massive and compact galaxies (superdense galaxies, hereafter SDGs) at z=0.03-0.11 in the Padova-Millennium Galaxy and Group Catalogue (PM2GC), a spectroscopically complete sample representative of the general field population of the local universe. We find that compact galaxies with radii and mass densities comparable to high-z massive and passive galaxies represent 4.4% of all galaxies with stellar masses above 3x10^10^M_{sun}_, yielding a number density of 4.3x10^-4^h^3^/Mpc^3^. Most of them are S0s (70%) or ellipticals (23%), are red, and have intermediate-to-old stellar populations, with a median luminosity-weighted age of 5.4Gyr and a median mass-weighted age of 9.2Gyr. Their velocity dispersions and dynamical masses are consistent with the small radii and high stellar mass estimates. Comparing with the WINGS sample of cluster galaxies at similar redshifts, the fraction of SDGs is three times smaller in the field than in clusters, and cluster SDGs are on average 4Gyr older than field SDGs. We confirm the existence of a universal trend of smaller radii for older luminosity-weighted ages at fixed galaxy mass. As a consequence, the median mass-size relation shifts toward smaller radii for galaxies with older stars, but the effect is much more pronounced in clusters than in the field. Our results show that, on top of the well-known dependence of stellar age on galaxy mass, the luminosity-weighted age of galaxies depends on galaxy compactness at fixed mass and, for a fixed mass and radius, on environment. This effect needs to be taken into account in order not to overestimate the evolution of galaxy sizes from high to low z. Our results and hierarchical simulations suggest that a significant fraction of the massive compact galaxies at high z have evolved into compact galaxies in galaxy clusters today. When stellar age and environmental effects are taken into account, the average amount of size evolution of individual galaxies between high and low z is mild, a factor ~1.6.
1335. PMS stars in the Cepheus flare region
ID:
ivo://CDS.VizieR/J/ApJS/185/451
Title:
PMS stars in the Cepheus flare region
Short Name:
J/ApJS/185/451
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of optical spectroscopic and BVR_C_I_C_ photometric observations of 77 pre-main-sequence (PMS) stars in the Cepheus flare region. A total of 64 of these are newly confirmed PMS stars, originally selected from various published candidate lists. We estimate effective temperatures and luminosities for the PMS stars, and comparing the results with PMS evolutionary models, we estimate stellar masses of 0.2-2.4M_{sun}_ and stellar ages of 0.1-15Myr. Among the PMS stars, we identify 15 visual binaries with separations of 2-10". From archival IRAS, Two Micron All Sky Survey, and Spitzer data, we construct their spectral energy distributions (SEDs) and classify 5% of the stars as Class I, 10% as Flat SED, 60% as Class II, and 3% as Class III young stellar objects. We identify 12 classical T Tauri stars and two weak-line T Tauri stars as members of NGC 7023, with a mean age of 1.6Myr. The 13 PMS stars associated with L1228 belong to three small aggregates: RNO 129, L1228A, and L1228S. The age distribution of the 17 PMS stars associated with L1251 suggests that star formation has propagated with the expansion of the Cepheus flare shell. We detect sparse aggregates of ~6-7Myr old PMS stars around the dark clouds L1177 and L1219, at a distance of ~400pc. Three T Tauri stars appear to be associated with the Herbig Ae star SV Cep at a distance of 600pc. Our results confirm that the molecular complex in the Cepheus flare region contains clouds of various distances and star-forming histories.
1336. PN and HII regions in NGC6822
ID:
ivo://CDS.VizieR/J/A+A/495/447
Title:
PN and HII regions in NGC6822
Short Name:
J/A+A/495/447
Date:
21 Oct 2021
Publisher:
CDS
Description:
Images obtained with the CTIO 4-m telescope and the MOSAIC-2 wide field camera in [OIII] 5007 and Halpha on-band and off-band filters are analyzed to search for emission line objects in the dwarf galaxy NGC 6822. In particular we search for planetary nebula (PN) candidates. In addition, imaging and spectroscopy of a sub-sample of objects obtained with the ESO VLT and FORS 2 spectrograph are used to calibrate the MOSAIC imaging. In the continuum-subtracted images, a large number of line emission regions were detected, for which we measured instrumental magnitudes in all the filters. The [OIII] 5007 and Halpha+[NII] magnitudes were calibrated with the spectroscopy.
1337. PNe and HII regions plasma diagnostics
ID:
ivo://CDS.VizieR/J/MNRAS/428/3443
Title:
PNe and HII regions plasma diagnostics
Short Name:
J/MNRAS/428/3443
Date:
21 Oct 2021
Publisher:
CDS
Description:
We carry out plasma diagnostic analyses for 123 planetary nebulae (PNe) and 42 HII regions using the NII and OII optical recombination lines (ORLs). New effective recombination coefficients for the NII and OII optical recombination spectra are used. These data were calculated under the intermediate coupling scheme for a number of electron temperature (Te) and density (Ne) cases. We use a new method to determine the Te's and Ne's for the nebular sample, combining the ORLs with the most reliable measurements for each ion and the predicted intensities that are based on the new atomic data. Uncertainties of the derived Te and Ne are estimated for each object. The diagnostic results from heavy element ORLs show reasonable agreement with previous calculations in the literature. We compare the electron temperatures derived from the NII and OII ORLs, Te(ORLs), and those from the collisionally excited lines (CELs), Te(CELs), as well as the hydrogen Balmer jump, Te(HIBJ), especially for the PNe with large abundance discrepancies. Temperatures from the HeI recombination lines, Te(HeI), are also used for comparison if available. For all the objects included in our sample, Te(ORLs) are lower than Te(HIBJ), which are in turn systematically lower than Te(CELs). PNe with Te(HeI) available show the relation Te(ORLs)<=Te(HeI)<=Te(HIBJ)<=Te(CELs), which is consistent with predictions from the bi-abundance nebular model postulated by Liu et al. (2000MNRAS.312..585L).
1338. PNe in 5 nearby galaxies
ID:
ivo://CDS.VizieR/J/ApJ/703/894
Title:
PNe in 5 nearby galaxies
Short Name:
J/ApJ/703/894
Date:
21 Oct 2021
Publisher:
CDS
Description:
As the second step in our investigation of the mass-to-light ratio of spiral disks, we present the results of a spectroscopic survey of planetary nebulae (PNe) in five nearby, low-inclination galaxies: IC 342, M74 (NGC 628), M83 (NGC 5236), M94 (NGC 4736), and M101 (NGC 5457). Using 50 setups of the WIYN/Hydra and Blanco/Hydra spectrographs, and 25 observations with the Hobby-Eberly Telescope's Medium Resolution Spectrograph, we determine the radial velocities of 99, 102, 162, 127, and 48 PNe, respectively, to a precision better than 15km/s. Although the main purpose of this data set is to facilitate dynamical mass measurements throughout the inner and outer disks of large spiral galaxies, our spectroscopy has other uses as well. Here, we co-add these spectra to show that, to first order, the [OIII] and Balmer line ratios of PNe vary little over the top ~1.5mag of the PN luminosity function.
1339. PNe in the elliptical galaxy NGC 821
ID:
ivo://CDS.VizieR/J/ApJ/721/369
Title:
PNe in the elliptical galaxy NGC 821
Short Name:
J/ApJ/721/369
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a slitless spectroscopy method with the 8.2m Subaru telescope and its FOCAS Cassegrain spectrograph, we have increased the number of planetary nebula (PN) detections and PN velocity measurements in the flattened elliptical galaxy NGC 821. A comparison with the detections reported previously by the Planetary Nebulae Spectrograph group indicates that we have confirmed most of their detections. The velocities measured by the two groups, using different telescopes, spectrographs, and slitless techniques, are in good agreement. We have built a combined sample of 167 PNs and have confirmed the Keplerian decline of the line-of-sight velocity dispersion reported previously. We also confirm misaligned rotation from the combined sample. A dark matter halo may exist around this galaxy, but it is not needed to keep the PN velocities below the local escape velocity as calculated from the visible mass. We have measured the m(5007) magnitudes of 145 PNs and produced a statistically complete sample of 40 PNs in NGC 821. The resulting PN luminosity function (PNLF) was used to estimate a distance modulus of 31.4mag, equivalent to 19Mpc.
1340. PNe in the Virgo elliptical galaxy NGC 4649
ID:
ivo://CDS.VizieR/J/ApJ/736/65
Title:
PNe in the Virgo elliptical galaxy NGC 4649
Short Name:
J/ApJ/736/65
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a slitless spectroscopy method with (1) the 8.2m Subaru telescope and its FOCAS Cassegrain spectrograph and (2) the ESO Very Large Telescope unit 1 (Antu) and its FORS2 Cassegrain spectrograph, we have detected 326 planetary nebulae (PNs) in the giant Virgo elliptical galaxy NGC 4649 (M60) and measured their radial velocities. After rejecting some PNs more likely to belong to the companion galaxy NGC 4647, we have built a catalog with kinematic information for 298 PNs in M60. Using these radial velocities, we have concluded that they support the presence of a dark matter halo around M60. Based on an isotropic, two-component Hernquist model, we estimate the dark matter halo mass within 3R_e_ to be 4x10^11^M_{sun}_, which is almost one-half of the total mass of about 10^12^M_{sun}_ within 3R_e_. This total mass is similar to that estimated from globular cluster, XMM-Newton, and Chandra observations. The dark matter becomes dominant outside. More detailed dynamical modeling of the PN data is being published in a companion paper. We have also measured the m(5007) magnitudes of many of these PNs and built a statistically complete sample of 218 PNs. The resulting PN luminosity function (PNLF) was used to estimate a distance modulus of 30.7+/-0.2mag, equivalent to 14+/-1Mpc. This confirms an earlier PNLF distance measurement based on a much smaller sample. The PNLF distance modulus remains smaller than the surface brightness fluctuation distance modulus by 0.4mag.