- ID:
- ivo://CDS.VizieR/J/AJ/162/11
- Title:
- EDEN project: Flare activity of nearby M-dwarf Wolf 359
- Short Name:
- J/AJ/162/11
- Date:
- 16 Mar 2022 00:09:17
- Publisher:
- CDS
- Description:
- We report the flare activity of Wolf359, the fifth closest star to the Sun and a candidate exoplanet-hosting M-dwarf. The star was a target of the Kepler/K2 mission and was observed by the EDEN project, a global network of 1-2m class telescopes for detection and characterization of rocky exoplanets in the habitable zones of late M-dwarfs within 50 light year from the solar system. In the combination of the archived K2 data and our EDEN observations, a total of 872 flares have been detected, 861 with the K2 (860 in the short-cadence and 18 in the long-cadence data, with 17 long-cadence events having short-cadence counterparts) and 11 with EDEN. Wolf 359 has relatively strong flare activity even among flaring M-dwarfs, in terms of the flare activity indicator (FA) defined as the integrated flare energy relative to the total stellar bolometric energy, where FA={sum}E_f_/{int}L_bol_dt~8.93x10^-5^ for the long-cadence flares, whereas for K2 short cadence and EDEN flares, the FA values are somewhat larger, FA~6.67 x 10^-4^ and FA~5.25x10^-4^, respectively. Such a level of activity, in accordance with the rotation period (P_rot_), suggests the star to be in the saturation phase. The size of the starspots is estimated to be at least 1.87%{+/-}0.59% of the projected disk area of Wolf359. We find no correlation of FA with the stellar rotational phase. Our analysis indicates a flare frequency distribution in a power-law form of dN/dE{prop}E^-{alpha}^ with {alpha}=2.13{+/-}0.14, equivalent to an occurrence rate of flares E_f_>~10^31^erg about once per day and of superflares with E_f_>~10^33^erg approximately 10 times per year. These superflares may impact the habitability of system in multiple ways, the details of which are topics for future investigations.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/248/33
- Title:
- Edge-on HI-rich LSB galaxies from ALFALFA
- Short Name:
- J/ApJS/248/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Low surface brightness galaxies (LSBGs) are defined as galaxies that are fainter than dark night sky and are important for studying our universe. Particularly, edge-on galaxies are useful for the study of rotational velocity and dynamical properties of galaxies. Hence here we focus on searching for edge-on LSBGs. In order to find these edge-on dim galaxies, a series of effects caused by inclination, including the surface brightness profile, internal extinction, and scale length, have been corrected. In this work, we present a catalog of 281 edge-on LSBG candidates, which are selected from the crossmatch between Sloan Digital Sky Survey Data Release 7 and the 40% ALFALFA catalog. We also present the properties of these edge-on LSBG candidates including the absolute magnitude, central surface brightness, B-V color, scale length, and relative thickness. Our result suggests that the correction of inclination effects is very important for obtaining a complete sample of LSBGs.
- ID:
- ivo://CDS.VizieR/J/A+A/642/A164
- Title:
- Edge-on protoplanetary disks ALMA images
- Short Name:
- J/A+A/642/A164
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to study vertical settling and radial drift of dust in protoplanetary disks from a different perspective: an edge-on view. An estimation of the amplitude of settling and drift is highly relevant to understanding planet formation. We analyze a sample of 12 HST-selected edge-on protoplanetary disks for which the vertical extent of the emission layers can be constrained directly. We present ALMA high angular resolution continuum images (0.1arcsec) of these disks at two wavelengths, 0.89mm and 2.06mm (respectively ALMA bands 7 and 4), supplemented with archival band 6 data (1.33mm) where available. For most sources, the millimeter continuum emission is more compact than the scattered light, both in the vertical and radial directions. Six sources are resolved along their minor axis in at least one millimeter band, providing direct information on the vertical distribution of the millimeter grains. For the second largest disk of the sample, the significant difference in vertical extent between band 7 and band 4 suggests efficient size-selective vertical settling of large grains. Furthermore, the only Class I object in our sample shows evidence of flaring in the millimeter. Along the major axis, all disks are well resolved. Four of them are larger in band 7 than in band 4 in the radial direction, and three have a similar radial extent in all bands. For all disks, we derive the millimeter brightness temperature and spectral index maps. We find that the disks are likely optically thick and that the dust emission reveals low brightness temperatures in most cases (<10K). The integrated spectral indices are similar to those of disks at lower inclination. The comparison of a generic radiative transfer disk model with our data shows that at least 3 disks are consistent with a small millimeter dust scale height, of a few au (measured at r=100au). This is in contrast with the more classical value of h_g_~10au derived from scattered light images and from gas line measurements. These results confirm, by direct observations, that large (millimeter) grains are subject to significant vertical settling in protoplanetary disks.
- ID:
- ivo://CDS.VizieR/J/MNRAS/431/240
- Title:
- Edinburgh-Cape Blue Object Survey. III.
- Short Name:
- J/MNRAS/431/240
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Edinburgh-Cape Blue Object Survey seeks to identify point sources with an ultraviolet excess. Results for zone 2 of the survey are presented here, covering that part of the South Galactic Cap between 30 and 40{deg} from the Galactic plane and south of about -12.3{deg} of declination. Edinburgh-Cape zone 2 comprises 66 UK Schmidt Telescope fields covering about 1730sq.deg, in which we find some 892 blue objects, including 423 hot subdwarfs (~47%); 128 white dwarfs (14%); 25 cataclysmic variables (~3%); 119 binaries (~13%), mostly composed of a hot subdwarf and a main-sequence F or G star; 66 horizontal branch stars (~7%) and 48 "star-like" extragalactic objects (~5%). A further 362 stars observed in the survey, mainly low-metallicity F- and G-type stars, are also listed. Both low-dispersion spectroscopic classification and UBV photometry are presented for almost all of the hot objects and either spectroscopy or photometry (or both) for the cooler ones.
- ID:
- ivo://CDS.VizieR/J/MNRAS/287/867
- Title:
- Edinburgh-Cape Blue Object Survey. Zone 1.
- Short Name:
- J/MNRAS/287/867
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results for Zone 1 of the Edinburgh-Cape (EC) Blue Object Survey are presented. This zone covers that part of the North Galactic Cap more than ~30{deg} from the Galactic plane and south of about -12.3{deg} declination (although a few fields north of this declination are included). The zone effectively complements the Palomar-Green Survey in the North Galactic Cap, although the EC Survey should be more complete to a fainter limit (B=16.5mag) and to somewhat redder stars (U-B bluer than about -0.4). Zone 1 covers approximately 1560{deg}^2^ and contains 675 blue objects far which we list equatorial coordinates accurate to ~1arcsec, UBV photoelectric photometry, and spectral types determined from moderate-dispersion (100{AA}/mm) spectrograms.
- ID:
- ivo://CDS.VizieR/J/MNRAS/459/4343
- Title:
- Edinburgh-Cape Blue Object Survey. Zones 4-6
- Short Name:
- J/MNRAS/459/4343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results for the remaining zones of the Edinburgh-Cape (EC) Blue Object survey are presented. These are incomplete, but lie in that part of the South Galactic Cap between 50deg and 90deg from the Galactic plane and south of about -12.3{deg} of declination. This part of the survey comprises 79 UK Schmidt Telescope fields covering about 2150deg^2^, in which we find 536 blue objects - including hot subdwarfs (~33 per cent), white dwarfs (~30 per cent), binaries (~12 per cent), cataclysmic variables (~1.5 per cent) and some 'star-like' galaxies (~12 per cent). A further 254 stars observed in the survey, mainly low-metallicity F- and G-type stars, are also listed. Low-dispersion spectroscopic classification is given for all the hot objects and UBV photometry for most of them. Either spectroscopy or photometry is listed for the cooler types.
- ID:
- ivo://CDS.VizieR/VII/175
- Title:
- Edinburgh-Durham Southern Galaxy Cat. - Cluster Cat.
- Short Name:
- VII/175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Edinburgh-Durham Cluster Catalogue (EDCC). This is the first machine-based, objectively selected sample of clusters of galaxies. It consists of 737 clusters or groups of all richnesses, over 0.5 sr of sky, centred on the South Galactic Pole (SGP). The primary galaAy data set for the cluster survey is the Edinburgh-Durham Southern Galaxy Catalogue (EDSGC). The EDCC was constructed using an automatic peak-finding algorithm and is complete to m_10_(b_j_) = 18.75. In a comparison with the Abell clusters in the same region, we detect 80 per cent of their rich clusters nominally brighter than our completion limit in addition to many new systems. This suggests that the EDCC is 90 per cent complete for Abell-type clusters. We also conclude that the Abell magnitude system is biased towards bright magnitudes for most of their clusters, and that their richness estimates are prone to a larger uncertainty than they suggest. The EDCC therefore supersedes the Abell catalogue as a data base for statistical studies of cluster properties.
- ID:
- ivo://CDS.VizieR/J/MNRAS/274/1071
- Title:
- Edinburgh-Milano cluster redshift survey
- Short Name:
- J/MNRAS/274/1071
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present the redshifts of the galaxies and galaxy clusters which form the Edinburgh-Milano (EM) cluster redshift survey. A total of 777 galaxy redshifts have been measured in 94 clusters extracted from the digitized Edinburgh-Durham Cluster Catalogue. We also present the radial velocity dispersions for 37 clusters. Observational and data reduction techniques are discussed in detail, together with the strategy adopted to determine the mean redshift of a cluster and to identify and discard plausible phantom clusters. Some 10 per cent of our clusters show heavy contamination, indicating that projection is a serious problem for optically selected, rich clusters. The median velocity dispersion estimated for a subsample of richness R>=1 clusters is 742+/-63km/s. From a simple comparison with {OMEGA}=1 cold dark matter models of structure formation, these results favour a biasing parameter b=1.6-2.0 and are inconsistent with a bias outside of the range b=1.3-2.5.
4859. EE Aqr UBV light curves
- ID:
- ivo://CDS.VizieR/J/AJ/139/1486
- Title:
- EE Aqr UBV light curves
- Short Name:
- J/AJ/139/1486
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- EE Aqr is a 7.9mag Algol variable with a 12hr orbital period. The Wilson-Devinney program is used to simultaneously solve 11 previously published light curves together with two existing radial velocity curves. The resulting masses are M_1_=2.24+/-0.13M_{sun}_ and M_2_=0.72+/-0.04M_{sun}_, and the radii are R_1_=1.76+/-0.03R_{sun}_ and R_2_=1.10+/-0.02R_{sun}_. The system has the lower-mass component completely filling its Roche lobe. Its distance from Hipparcos observations is 112+/-10pc. An improved ephemeris is derived, and no deviations in the period over time were seen. Light and velocity curve parameters, orbital elements, and absolute dimensions are presented, plus a comparison is made with previous solutions.
- ID:
- ivo://CDS.VizieR/J/other/JAD/25.1
- Title:
- EE Cam, FG Vir and 44 Tau light curves
- Short Name:
- J/other/JAD/25.1
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The three delta Scuti pulsators EE Cam, FG Vir and 44 Tau are of special interest because their pulsation properties are different from those expected from the low rotational velocities indicated by spectroscopic measurements. This paper presents the previously unpublished high-precision photometric data obtained by the Delta Scuti Network during 780 nights.