- ID:
- ivo://CDS.VizieR/J/AJ/121/3048
- Title:
- Multicolor photometry in NGC 1512 and NGC 5248
- Short Name:
- J/AJ/121/3048
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present broadband (U, V, I, and H) and narrowband (H{alpha}+[N II] and Pa{alpha}) images of the circumnuclear starburst rings in two nearby spiral galaxies, NGC 1512 and NGC 5248, obtained with the WFPC2 and NICMOS cameras on HST. Combined with previously published ultraviolet (UV) HST images at 2300{AA} these data provide a particularly wide wavelength range with which to study the properties of the stellar populations, the gas, and the dust in the rings.
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- ID:
- ivo://CDS.VizieR/J/AJ/144/191
- Title:
- Multicolor photometry of 135 star clusters in M31
- Short Name:
- J/AJ/144/191
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present photometry for young star clusters in M31, which are selected from Caldwell et al. These star clusters have been observed as part of the Beijing-Arizona-Taiwan-Connecticut (BATC) Multicolor Sky Survey from 1995 February to 2008 March. The BATC images including these star clusters are taken with 15 intermediate-band filters covering 3000-10000{AA}. Combined with photometry in the GALEX far- and near-ultraviolet, broadband UBV RI, SDSS ugriz, and infrared JHK_s_ of Two Micron All Sky Survey, we obtain their accurate spectral energy distributions (SEDs) from 1538 to 20000{AA}. We derive these star clusters' ages and masses by comparing their SEDs with stellar population synthesis models. Our results are in good agreement with previous determinations. The mean value of age and mass of young clusters (<2Gyr) is about 385Myr and 2x10^4^M_{sun}_, respectively. There are two distinct peaks in the age distribution, a highest peak at age ~60Myr and a secondary peak around 250Myr, while the mass distribution shows a single peak around 10^4^M_{sun}_. A few young star clusters have two-body relaxation times greater than their ages, indicating that those clusters have not been well dynamically relaxed and therefore have not established the thermal equilibrium. There are several regions showing aggregations of young star clusters around the 10kpc ring and the outer ring, indicating that the distribution of the young star clusters is well correlated with M31's star-forming regions. The young massive star clusters (age<=100Myr and mass>=10^4^M_{sun}_) show apparent concentration around the ring splitting region, suggesting a recent passage of a satellite galaxy (M32) through M31 disk.
- ID:
- ivo://CDS.VizieR/J/A+A/556/A55
- Title:
- Multi-color photometry of star-forming galaxies
- Short Name:
- J/A+A/556/A55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We estimate the galaxy stellar mass function and stellar mass density for star-forming and quiescent galaxies with 0.2<z<4. We construct a large, deep sample of galaxies selected using the new UltraVISTA DR1 data release (Cat. J/A+A/544/A156). Our analysis is based on precise 30-band photometric redshifts. By comparing these photometric redshifts with 10800 spectroscopic redshifts from the zCOSMOS bright (Cat. J/ApJS/172/70) and faint (Lilly et al. in prep) surveys, we find an accuracy of sigma(dz/(1+z))=0.008 at i<22.5 and sigma(dz/(1+z))=0.03 at 1.5<z<4.
- ID:
- ivo://CDS.VizieR/J/PASP/106/949
- Title:
- Multicolor polarimetry of Be stars
- Short Name:
- J/PASP/106/949
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Optical polarization data in the UBVRI filter system for eight bright northern Be stars are presented here as the continuation of a long-term monitoring project begun in 1984. There are no strong cases of night-to-night variability, and the only star showing unmistakable changes in polarization from year to year over the nine years covered by the program is Pi Aquarii. Even though the observed sample spans a wide range in spectral type, vsini, and degree of intrinsic polarization, the normalized wavelength dependence of the polarization is surprisingly similar for all of the stars. Analysis of the wavelength dependence of the variable polarization of {pi} Aqr in terms of a simple equatorial-disk model suggests that changes in the circumstellar electron number density alone may be sufficient to account for the observations, but it is not clear what real physical mechanism is involved.
- ID:
- ivo://CDS.VizieR/J/AJ/154/231
- Title:
- Multi-epoch multi-band photometry of B1-392
- Short Name:
- J/AJ/154/231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Ongoing and future surveys with repeat imaging in multiple bands are producing (or will produce) time-spaced measurements of brightness, resulting in the identification of large numbers of variable sources in the sky. A large fraction of these are periodic variables: compilations of these are of scientific interest for a variety of purposes. Unavoidably, the data sets from many such surveys not only have sparse sampling, but also have embedded frequencies in the observing cadence that beat against the natural periodicities of any object under investigation. Such limitations can make period determination ambiguous and uncertain. For multiband data sets with asynchronous measurements in multiple passbands, we wish to maximally use the information on periodicity in a manner that is agnostic of differences in the light-curve shapes across the different channels. Given large volumes of data, computational efficiency is also at a premium. This paper develops and presents a computationally economic method for determining periodicity that combines the results from two different classes of period-determination algorithms. The underlying principles are illustrated through examples. The effectiveness of this approach for combining asynchronously sampled measurements in multiple observables that share an underlying fundamental frequency is also demonstrated.
- ID:
- ivo://CDS.VizieR/J/A+A/520/A89
- Title:
- Multi-epoch photometry of {delta} Ori
- Short Name:
- J/A+A/520/A89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For years, {delta} Ori was considered a normal binary with an O9.5 II primary exhibiting apsidal-line advance. However, in 2002 radial-velocity curves of both binary components derived from the IUE and optical spectra using the cross-correlation technique have been published by Harvin et al. (2002ApJ...565.1216H); surprisingly low masses of 11.2 and 5.6M_{sun}_ were obtained. We obtained new spectra in the red spectral region and new UBV photometry. Using all published photometry and radial velocities, we deduced more accurate orbital and apsidal line periods. The main result of this paper is to show that the observed line spectra of {delta} Ori are composed of the lines of the O9.5 II primary and a similarly hot tertiary, while the lines of a cooler B-type secondary are too faint to be detected in the available spectra. The character of the light curve (low-amplitude partial eclipses and a non-negligible scatter of the data) does not allow for a unique light-curve solution. Nevertheless, we show that the assumption of normal primary-component mass and radius corresponding to the O9.5 II classification (25M_{sun}_, 16-17R_{sun}_) leads to consistent parameters for the system.
- ID:
- ivo://CDS.VizieR/J/other/RMxAA/35.187
- Title:
- Multifrequency catalog of LINERs
- Short Name:
- J/other/RMxAA/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first Catalog of Low Ionization Emission Line Galaxies (LINERs or Liners, which is the simplest name, and which we shall adopt in what follows). The Catalog "MCL" (Multifrequency Catalog of Liners), contains 476 entries and contains both broad-band and monochromatic emission data (ranging from radio to X-ray frequencies) of colors, and other data compiled from the literature and various data bases, as indicated in the references. Most of the galaxies can be considered "pure" Liners on the basis of the Veilleux & Osterbrock (1987ApJS...63..295V) classification as suggested by Ho, Filippenko, & Sargent (1997ApJS..112..315H). However, a considerable number of transition (Liners-H II or Liners-Starburst) objects are also included. One of the open questions, is whether Liners should be considered as a class of galaxies (like Seyfert galaxies for instance) or rather, as an heterogeneous group of objects. We believe the study of Liners as a group is very interesting, precisely because they very likely represent a transition between non-thermal and starburst activity, and probably also between "active" and "non- active" galaxies. This catalog may be used as a basis for statistical research. A preliminary discussion of the main statistical properties of Liners, in the range from radio to X-ray frequencies, is given here.
- ID:
- ivo://CDS.VizieR/J/A+AS/114/341
- Title:
- Multifrequency monitoring of RU Lupi
- Short Name:
- J/A+AS/114/341
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we present the results of a long campaign of coordinated (sometimes simultaneous) multifrequency observations, from X-ray to radio wavelengths of the extreme T Tauri star RU Lupi. The large amount of data obtained can be useful to understanding the physics governing the intriguing behaviour of this pre-main-sequence star. In particular, from the whole set of data, a model with a protoplanetary accretion disk around a moderately magnetic star seems to be the most promising picture for this source.
- ID:
- ivo://CDS.VizieR/J/A+A/623/A65
- Title:
- Multiphotometry of M31 outer halo globular clusters
- Short Name:
- J/A+A/623/A65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present photometry of 53 globular clusters (GCs) in the M31 outer halo, including the GALEX FUV and NUV, SDSS ugriz, 15 intermediate-band filters of BATC, and 2MASS JHKs bands. By comparing the multicolour photometry with stellar population synthesis models, we determine the metallicities, ages, and masses for these GCs, aiming to probe the merging/accretion history of M31. We find no clear trend of metallicity and mass with the de-projected radius. The halo GCs with age younger than ~8Gyr are mostly located at the de-projected radii around 100kpc, but this may be due to a selection effect. We also find that the halo GCs have consistent metallicities with their spatially-associated substructures, which provides further evidence of the physical association between them. Both the disk and halo GCs in M31 show a bimodal luminosity distribution. However, we should emphasize that there are more faint halo GCs which are not being seen in the disk. There are more faint halo GCs than the disk ones, and these faint GCs constitute the fainter part in the luminosity function. The bimodal luminosity function of the halo GCs may reflect different origin or evolution environment in their original hosts. The M31 halo GCs includes one intermediate metallicity group (-1.5<[Fe/H]<-0.4) and one metal-poor group ([Fe/H]<-1.5), while the disk GCs have one metal-rich group more. There are considerable differences between the halo GCs in M31 and the Milky Way (MW). The total number of M31 GCs is approximately three times more numerous than that of the MW, however, M31 has about six times the number of halo GCs in the MW. Compared to M31 halo GCs, the Galactic halo ones are mostly metal-poor. Both the numerous halo GCs and the higher-metallicity component are suggestive of an active merger history of M31.
- ID:
- ivo://CDS.VizieR/J/A+AS/121/223
- Title:
- Multiphotometry of NGC 6611
- Short Name:
- J/A+AS/121/223
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For the search of Herbig Ae/Be objects in the extremely young open cluster NGC 6611 we have selected a sample of 52 pre-main sequence candidates, discovered by Walker (1961ApJ...133..438W), Sagar & Joshi (1979Ap&SS..66....3S), Chini & Wargau (1990A&A...227..213C) and The et al. (1990A&AS...82..319T). We continue the approach of the last paper by studying each star individually with new and unpublished Walraven WULBV, Johnson/Cousins UBV(RI)_C_ and Johnson JHKLM photometric data as well as low resolution spectroscopy. For a description of the Walraven, UBVRI, IJHKLMN and RI Cousins photometric systems, see e.g. <GCPD/11>, <GCPD/08>, <GCPD/09> and <GCPD/54>
