- ID:
- ivo://CDS.VizieR/J/A+A/417/945
- Title:
- BVI & JHK photometry of NGC 3960
- Short Name:
- J/A+A/417/945
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a BVI photometric and astrometric catalogue of the open cluster NGC 3960, down to limiting magnitude V~22, obtained from observations taken with the Wide Field Imager camera at the MPG/ESO 2.2m Telescope at La Silla. The photometry of all the stars detected in our field of view has been used to estimate a map of the strong differential reddening affecting this area. Our results indicate that, within the region where the cluster dominates, the E(V-I) values range from 0.21 up to 0.78, with E(V-I)=0.36 (E(B-V)=0.29) at the nominal cluster centroid position; color excesses E(V-I) up to 1 mag have been measured in the external regions of the field of view where field stars dominate. The reddening-corrected color-magnitude diagram (CMD) allows us to conclude that the cluster has an age between 0.9 and 1.4Gyr and a distance modulus of (V-M_V)_0=11.35. Based on observations made with the European Southern Observatory telescopes obtained from the the ESO/ST-ECF Science Archive Facility.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/402/425
- Title:
- BVIJHK properties of Single Stellar Populations
- Short Name:
- J/A+A/402/425
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a large grid of photometric properties of single stellar populations that focuses on the near infrared properties of intermediate age populations. The underlying model was presented in recent articles, where we compared its predictions with observations of properties of star clusters and of asymptotic giant branch populations of Local Group galaxies. The grid is made available in tabular form. We present the time evolution of optical and near-infrared broadband colours in the BVIJHK passbands, with ages ranging from 50Myr to 15Gyr, and for initial chemical compositions [Z=0.0004, Y=0.23], [Z=0.004, Y=0.24], [Z=0.008, Y=0.25], [Z=0.02, Y=0.28], and [Z= 0.05, Y=0.352]. The evolution of the stellar mass-to-light ratio in the V and K passbands is also provided. All the stellar models are followed from the zero age main sequence (ZAMS) to the central carbon ignition for massive stars, or to the end of the thermally pulsing regime of the asymptotic giant branch phase (TP-AGB) for low and intermediate mass stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/691/723
- Title:
- BVIJHKs observations of GRB 080319B
- Short Name:
- J/ApJ/691/723
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first gamma-ray burst (GRB) confirmed to be bright enough to be seen with the naked eye, GRB 080319B at redshift z=0.937, allowed for exquisite follow-up observations across the electromagnetic spectrum. We present our detailed optical and infrared (IR) observations of the afterglow, consisting of over 5000 images starting 51s after the GRB trigger, in concert with our own analysis of the Swift UVOT, Burst Alert Telescope (BAT), and XRT data. The event is extreme not only in observed properties but also intrinsically: it was the most luminous event ever recorded at optical and IR wavelengths and had an exceedingly high isotropic-equivalent energy release in {gamma}-rays. At early times, the afterglow evolution is broadly consistent with being reverse-shock dominated, but then is subsumed by a forward shock at around 1000s. The overall spectral energy distribution, spanning from ultraviolet through near-IR wavelengths, shows no evidence for a significant amount of dust extinction in the host frame. The afterglow evolution, however, is highly chromatic: starting at about 1000s the index shifts blueward before shifting back to the red at late times. In our deepest late-time observations, we find tentative evidence for an optical jet break and a luminous supernova. Finally, we examine the detectability of such events with current and future facilities and find that such an event could be detected in gamma rays by BAT out to z=10.7 (8{sigma}), while the nominal EXIST sensitivity would allow detection to z~32. At the K band, this source would have been easily detected with meter-class telescopes to z~17.
- ID:
- ivo://CDS.VizieR/J/MNRAS/355/1272
- Title:
- BVIJHKs photometry around CG 12
- Short Name:
- J/MNRAS/355/1272
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A method for determining distances to dark clouds and Bok globules based on broad-band optical and near-infrared photometry is presented. In this method, intrinsic colour indices of stars projected towards the direction of a cloud are computed by dereddening the observed colour indices using various trial values of extinction A_V_ and a standard extinction law. The computed intrinsic colour indices for a star are then compared with the intrinsic colour indices of normal main-sequence stars and a spectral type is assigned to the star for which the computed colour indices best match the standard intrinsic colour indices. Distances (d) to the stars are determined using the A_V_ and absolute magnitudes (M_V_) corresponding to the spectral types thus obtained. A plot of A_V_ against d undergoes a sharp rise at a distance corresponding to the distance to the cloud. Using this method, we have determined a distance of 550pc to the cometary globule CG 12.
- ID:
- ivo://CDS.VizieR/J/AJ/121/768
- Title:
- BVIJH photometry of M82
- Short Name:
- J/AJ/121/768
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-resolution HST imaging in the optical (WFPC2) and near-infrared (NICMOS) of a disk region 1kpc northeast of the starburst core in the nearby galaxy M82.
- ID:
- ivo://CDS.VizieR/J/ApJ/663/277
- Title:
- BVI of NGC 5466 red giants and blue stragglers
- Short Name:
- J/ApJ/663/277
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present wide-field BVI photometry for about 11500 stars in the low-metallicity cluster NGC 5466. We have detected the red giant branch bump for the first time, although it is at least 0.2mag fainter than expected relative to the turnoff. The number of red giants (relative to main-sequence turnoff stars) is in excellent agreement with stellar models from the Yonsei-Yale and Teramo groups, and slightly high compared to Victoria-Regina models. This adds to evidence that an abnormally large ratio of red giant to main-sequence stars is not correlated with cluster metallicity.
- ID:
- ivo://CDS.VizieR/J/ApJ/871/33
- Title:
- BVI photometric calatog of star clusters in NGC4589
- Short Name:
- J/ApJ/871/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NGC4589, a bright E2 merger-remnant galaxy, hosts the peculiar fast and faint calcium-rich supernova SNIb SN2005cz. The progenitor of Ca-rich SNeIb has been controversial: it could be (1) a young, massive star with 6-12M{sun} in a binary system, or (2) an old, low-mass star in a binary system that was kicked out from the galaxy center. Moreover, previous distance estimates for this galaxy have shown a large spread, ranging from 20 to 60Mpc. Thus, using archival Hubble Space Telescope/Advanced Camera for Surveys (HST/ACS) F435W, F555W, and F814W images, we search for star clusters in NGC4589 in order to help resolve these issues. We find a small population of young star clusters with 25<V<=27(-7.1<M_V_<-5.1)mag and age <1Gyr in the central region at R<0.5' (<3.8kpc), thus supporting the massive-star progenitor scenario for SN2005cz. In addition to young star clusters, we also find a large population of old globular clusters. In contrast to previous results in the literature, we find that the color distribution of the globular clusters is clearly bimodal. The turnover (Vega) magnitude in the V-band luminosity functions of the blue (metal-poor) globular clusters is determined to be V_0_(max)=24.40{+/-}0.10mag. We derive the total number of globular clusters, N_GC_=640{+/-}50, and the specific frequency, S_N_=1.7{+/-}0.2. Adopting a calibration for the metal-poor globular clusters, M_V_(max) =-7.66{+/-}0.14mag, we derive a distance to this galaxy: (m-M)_0_=32.06{+/-}0.10(ran){+/-}0.15(sys) (d=25.8{+/-}2.2Mpc).
- ID:
- ivo://CDS.VizieR/J/A+A/484/609
- Title:
- BVI photometry and proper motions in M67
- Short Name:
- J/A+A/484/609
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The solar-age open cluster M 67 (C0847+ 120, NGC 2682) is a touchstone in studies of the old Galactic disk. Despite its outstanding role, the census of cluster membership for M 67 at fainter magnitudes and their properties are not well-established. Using proprietary and archival ESO data, we have obtained astrometric, photometric, and radial velocities of stars in a 34x33arcmin^2^ field centered on the old open cluster M 67. The two-epoch archival observations separated by 4-years and acquired with the Wide-Field Imager at the 2.2m MPG/ ESO telescope were reduced with our new astrometric techniques, as described in the first paper in this series (Anderson et al., 2006A&A...454.1029A). The same observations served to derive calibrated BVI photometry in M 67. Radial velocities were measured using the archival and new spectroscopic data obtained at the VLT.
- ID:
- ivo://CDS.VizieR/J/A+A/442/917
- Title:
- BVI photometry in Berkeley 73, 75 and 25
- Short Name:
- J/A+A/442/917
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- CCD BVI photometry of the faint open clusters Berkeley 73, Berkeley 75 and Berkeley 25 are presented. The two latter are previously unstudied clusters to our knowledge. While Berkeley 73 is found to be of intermediate-age (about 1.5Gyr old), Berkeley 75 and Berkeley 25 are old clusters, with ages greater than 3.0Gyr. We provide also estimates of the clusters size. All these clusters lie far away from the Galactic Center, at R_GC_>=16kpc, and quite high on the Galactic plane, at |Z_{sun}_|>=1.5kpc. They are therefore important targets to probe the properties of the structure of the Galaxy in this direction, where the Canis Major over-density has been discovered to be located.
- ID:
- ivo://CDS.VizieR/J/MNRAS/344/188
- Title:
- BVI photometry in Fornax cluster galaxies
- Short Name:
- J/MNRAS/344/188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present BVI photometry of 190 galaxies in the central 4x3deg^2^ region of the Fornax cluster observed with the Michigan Curtis Schmidt Telescope. Results from the Fornax Cluster Spectroscopic Survey (FCSS) and the Flair-II Fornax Surveys have been used to confirm the membership status of galaxies in the Fornax Cluster Catalogue (FCC, Cat. <VII/180>). In our catalogue of 213 member galaxies, 92 (43 per cent) have confirmed radial velocities.
