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- ID:
- ivo://CDS.VizieR/J/A+A/401/997
- Title:
- Wilson-Bappu relation in late-type stars
- Short Name:
- J/A+A/401/997
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wilson & Bappu (1957ApJ...125..661W) have shown the existence of a remarkable correlation between the width of the emission in the core of the K line of CaII and the absolute visual magnitude of late-type stars. Here we present a new calibration of the Wilson-Bappu effect based on a sample of 119 nearby stars. We use, for the first time, width measurements based on high resolution and high signal to noise ratio CCD spectra and absolute visual magnitudes from the Hipparcos database.
- ID:
- ivo://CDS.VizieR/J/MNRAS/412/1162
- Title:
- Wind-driving protostellar accretion discs
- Short Name:
- J/MNRAS/412/1162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We continue our study of weakly ionized protostellar accretion discs that are threaded by a large-scale magnetic field and power a centrifugally driven wind. It has been argued that there is already evidence in several protostellar systems that such a wind transports a significant fraction of the angular momentum from at least some part of the disc. We model this situation by considering a radially localized disc model in which the matter is everywhere well coupled to the field and the wind is the main repository of excess angular momentum. We consider stationary configurations in which magnetic diffusivity counters the shearing and advection of the magnetic field lines. In Wardle & Koenigl (1997, ASP Conf. Ser., 121, 561) we analysed the disc structure in the hydrostatic approximation (vertical motions neglected inside the disc) and presented exact disc/wind solutions for the ambipolar diffusivity regime. In Koenigl, Salmeron & Wardle (Paper I, 2010MNRAS.401..479K) we generalized the hydrostatic analysis to the Hall and Ohm diffusivity domains and used it to identify the disc parameter sub-regimes in which viable solutions with distinct physical properties can be expected to occur. In this paper we test the results of Paper I by deriving full numerical solutions (integrated through the sonic critical surface) of the disc equations in the Hall domain.
- ID:
- ivo://CDS.VizieR/J/AJ/154/45
- Title:
- WINERED CN-red band emission in comet C/2013 R1
- Short Name:
- J/AJ/154/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Although high-resolution spectra of the CN red-system band are considered useful in cometary sciences, e.g., in the study of isotopic ratios of carbon and nitrogen in cometary volatiles, there have been few reports to date due to the lack of high-resolution (R={lambda}/{Delta}{lambda}>20000) spectrographs in the near-infrared region around ~1 {mu}m. Here, we present the high-resolution emission spectrum of the CN red-system band in comet C/2013 R1 (Lovejoy), acquired by the near-infrared high-resolution spectrograph WINERED mounted on the 1.3 m Araki telescope at the Koyama Astronomical Observatory, Kyoto, Japan. We applied our fluorescence excitation models for CN, based on modern spectroscopic studies, to the observed spectrum of comet C/2013 R1 (Lovejoy) to search for CN isotopologues (^13^C^14^N and ^12^C^15^N). We used a CN fluorescence excitation model involving both a "pure" fluorescence excitation model for the outer coma and a "fully collisional" fluorescence excitation model for the inner coma region. Our emission model could reproduce the observed ^12^C^14^N red-system band of comet C/2013 R1 (Lovejoy). The derived mixing ratio between the two excitation models was 0.94(+0.02/-0.03):0.06(+0.03/-0.02), corresponding to the radius of the collision-dominant region of ~800-1600 km from the nucleus. No isotopologues were detected. The observed spectrum is consistent, within error, with previous estimates in comets of ^12^C/^13^C (~90) and ^14^N/^15^N (~150).
24675. WINGS B surface photometry
- ID:
- ivo://ia2.inaf.it/hosted/wings/cone/gasphotb
- Title:
- WINGS B surface photometry
- Short Name:
- WINGSGasphotb
- Date:
- 13 Mar 2019 11:58:32
- Publisher:
- IA2
- Description:
- This catalog contains the surface brightness measurements of ~41500 galaxies detected in the B images of the WINGS cluster survey. For each galaxy B magnitude, mean surface brightness, effective radius, Sersic index and axial ratio are given, together with their errors. These global parameters were obtained by simultaneously fitting the major and minor axis light growth curves of galaxies with a 2D flattened Sersic-law, convolved by the appropriate, space-varying PSF, which was previously evaluated by the tool itself. (http://adsabs.harvard.edu/abs/2006A%26A...446..373P)
- ID:
- ivo://CDS.VizieR/J/A+A/633/A104
- Title:
- WINGS cluster galaxies structural parameters
- Short Name:
- J/A+A/633/A104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a multi-wavelength analysis of the galaxies in nine clusters selected from the WINGS dataset, examining how galaxy structure varies as a function of wavelength and environment using the state of the art software galapagos-2. We simultaneously fit single-Sersic functions on three optical (u, B and V) and two near-infrared (J and K) bands thus creating a wavelength-dependent model of each galaxy. We measure the magnitudes, effective radius (Re), the Sersic index (n), axis ratio, and position angle in each band. The sample contains 790 cluster members (located close to the cluster centre <0.64xR200) and 254 non-member galaxies that we further separate based on their morphology into ellipticals, lenticulars, and spirals. We find that the Sersic index of all galaxies inside clusters remains nearly constant with wavelength while Re decreases as wavelength increases for all morphological types. We do not observe a significant variation on n and Re as a function of projected local density and distance from the clusters centre. Comparing the n and Re of bright cluster galaxies with a subsample of non-member galaxies we find that bright cluster galaxies are more concentrated (display high n values) and are more compact (low Re). Moreover, the light profile (N) and size (R) of bright cluster galaxies does not change as a function of wavelength in the same manner as non-member galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/637/A54
- Title:
- WINGS cluster survey second u-band extension
- Short Name:
- J/A+A/637/A54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the second u-band extension of the WIde-field Nearby Galaxy-cluster Survey (WINGS), obtained by imaging 39 clusters with the ESO-VLT survey telescope. It follows the first one, realized with several telescopes of the northern hemisphere in the U Cousin-Bessel filter band (Omizzolo et al., 2014A&A...561A.111O, Cat. J/A+A/561/A111), that covered 17 clusters. The u-band data, in combination with those already achieved by the WINGS survey, will permit a detailed multi-wavelength investigation of the properties of the member galaxies from the cluster center out to the periphery. We have derived with SEXT the main properties of the galaxies in the observed fields and measured the u-V colors on circular apertures of increasing radius. The photometric accuracy of the magnitudes has been calibrated with the standard stars and tested by means of comparisons with the u-band data of the Sloan Digital Sky Survey (SDSS). We present the catalogs of the photometric analysis performed by SEXT. Then we provide a brief analysis of the u-V vs V color-magnitude diagram of our clusters, the plots of the color as a function of the cluster-centric distance (for cluster members only) and the correlation of the current star formation rate (SFR) vs the absolute V and u magnitudes for the galaxies in the observed fields.
- ID:
- ivo://CDS.VizieR/J/A+A/497/667
- Title:
- WINGS: Deep optical phot. of 77 nearby clusters
- Short Name:
- J/A+A/497/667
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the second paper of a series devoted to the WIde Field Nearby Galaxy-cluster Survey (WINGS). WINGS is a long term project which is gathering wide-field, multi-band imaging and spectroscopy of galaxies in a complete sample of 77 X-ray selected, nearby clusters (0.04<z<0.07) located far from the galactic plane (|b|>200deg). The main goal of this project is to establish a local reference for evolutionary studies of galaxies and galaxy clusters. This paper presents the optical (B,V) photometric catalogs of the WINGS sample and describes the procedures followed to construct them. We have paid special care to correctly treat the large extended galaxies (which includes the brightest cluster galaxies) and the reduction of the influence of the bright halos of very bright stars. We have constructed photometric catalogs based on wide-field images in B and V bands using SExtractor. Photometry has been performed on images in which large galaxies and halos of bright stars were removed after modeling them with elliptical isophotes. We publish deep optical photometric catalogs (90% complete at V21.7, which translates to ~ MV* + 6 at mean redshift), giving positions, geometrical parameters, and several total and aperture magnitudes for all the objects detected. For each field we have produced three catalogs containing galaxies, stars and objects of "unknown" classification (~16%). From simulations we found that the uncertainty of our photometry is quite dependent of the light profile of the objects with stars having the most robust photometry and de Vaucouleurs profiles showing higher uncertainties and also an additional bias of ~-0.2m. The star/galaxy classification of the bright objects (V<20) was checked visually making negligible the fraction of misclassified objects. For fainter objects, we found that simulations do not provide reliable estimates of the possible misclassification and therefore we have compared our data with that from deep counts of galaxies and star counts from models of our Galaxy. Both sets turned out to be consistent with our data within ~5% (in the ratio galaxies/total) up to V~24. Finally, we remark that the application of our special procedure to remove large halos improves the photometry of the large galaxies in our sample with respect to the use of blind automatic procedures and increases (~16%) the detection rate of objects projected onto them.
24679. WINGS equivalent widths
- ID:
- ivo://ia2.inaf.it/hosted/wings/cone/eqwidth
- Title:
- WINGS equivalent widths
- Short Name:
- WINGSEqwidth
- Date:
- 13 Mar 2019 11:58:19
- Publisher:
- IA2
- Description:
- The catalog gives the measurements of the optical lines equivalent widths and statistical errors for a sample of ~4400 objects detected in 48 WINGS clusters for which the spectrum is available and reliable. Emission lines have negative EWs, and absorption lines positive EWs, with all the quantities given at rest frame. Spectra were obtained with WYFFOS@WHT and 2dF@AAT and have a resolution of 6 and 9 AA FWHM, respectively. The wavelength coverage ranges from ∼ 3590 to ∼ 6800 AA for the WHT observations, while spectra taken at the AAT cover the ∼ 3600 to ∼ 8000 AA domain. For each object the catalog gives also the magnitude and radial completeness (or weight) that, once combined, describe the global completeness of the sample. Finally a spectral classification is available, made on the basis of the presence/absence and intensity of spectral lines (following Poggianti et al., 1999): 1=e(a); 2=e(b); 3=e(c); 4=k; 5=k+a; 6=a+k.
- ID:
- ivo://CDS.VizieR/J/A+A/572/A87
- Title:
- WINGS galaxies surface photometry with GASPHOT
- Short Name:
- J/A+A/572/A87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the B, V, and K band surface photometry catalogs obtained by running the automatic software GASPHOT on galaxies from the WINGS cluster survey with isophotal areas larger than 200 pixels. The luminosity growth curves of stars and galaxies in a given catalog relative to a given cluster image were obtained simultaneously by slicing the image with a fixed surface brightness step in several SExtractor runs. Then, using a single Sersic law convolved with a space-varying point spread function (PSF), GASPHOT performed a simultaneous {chi}^2^ best-fit of the major- and minor-axis luminosity growth curves of galaxies. We outline the GASPHOT performances and compare our surface photometry with that obtained by SExtractor, GALFIT, and GIM2D. This analysis is aimed at providing statistical information about the accuracy that is generally achieved by the softwares for automatic surface photometry of galaxies.