- 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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- 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.
2165. BVIJH photometry of M82
- 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/876/8
- Title:
- BVI LCs and radial velocities of PSR J1306-40
- Short Name:
- J/ApJ/876/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- PSR J1306-40 is a millisecond pulsar (MSP) binary with a non-degenerate companion in an unusually long ~1.097 day orbit. We present new optical photometry and spectroscopy of this system, and model these data to constrain fundamental properties of the binary such as the component masses and distance. The optical data imply a minimum neutron star mass of 1.75+/-0.09M_{sun}_ (1{sigma}) and a high, nearly edge-on inclination. The light curves suggest a large hot spot on the companion, suggestive of a portion of the pulsar wind being channeled to the stellar surface by the magnetic field of the secondary, mediated via an intrabinary shock. The H{alpha} line profiles switch rapidly from emission to absorption near the companion inferior conjunction, consistent with an eclipse of the compact emission region at these phases. At our optically inferred distance of 4.7+/-0.5kpc, the X-ray luminosity is ~10^33^erg/s, brighter than nearly all known redbacks in the pulsar state. The long-period, subgiant-like secondary, and luminous X-ray emission suggest this system may be part of the expanding class of MSP binaries that are progenitors to typical field pulsar-white dwarf binaries.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/993
- Title:
- BVI light curves of RZ Lyr
- Short Name:
- J/MNRAS/423/993
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The analysis of recent, extended multicolour CCD and archive photoelectric, photographic and visual observations has revealed several important properties of RZ Lyr, an RRab-type variable exhibiting large-amplitude Blazhko modulation. On the time base of ~110yr, a strict anticorrelation between the pulsation- and modulation-period changes is established. The light curve of RZ Lyr shows a remarkable bump on the descending branch in the small-amplitude phase of the modulation, similarly to the light curves of bump Cepheids. We speculate that the stellar structure temporally suits a 4:1 resonance between the periods of the fundamental and one of the higher order radial modes in this modulation phase. The light-curve variation of RZ Lyr can be correctly fitted with a two-modulation-component solution; the 121-d period of the main modulation is nearly but not exactly four times longer than the period of the secondary modulation component. Using the inverse photometric method, the variations in the pulsation-averaged values of the physical parameters in different phases of both modulation components are determined.
- 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/A+A/435/507
- Title:
- BVI phot. of CFRS 0300+00 & 1415+52 fields galaxies
- Short Name:
- J/A+A/435/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains 75 field galaxies in two 10'x10' CFRS fields 0300+00 and 1415+52 with HST/WFPC2 image and deep ISOCAM observations. They are not detected in the ISO observations to a detection limit of 300{mu}Jy at 5{sigma} level. Magnitudes and Structural parameters in three HST bands and according morphological classification are presented
- ID:
- ivo://CDS.VizieR/J/A+A/503/87
- Title:
- BVI phot. of NGC3370 star cluster candidates
- Short Name:
- J/A+A/503/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the photometric and structural properties of the star cluster system in the late type Sc spiral NGC 3370. BVI observations from the Advanced Camera for Surveys on board of HST are used to analyse in detail the colours, magnitudes and spatial properties of cluster candidates. The final catalogue of sources used for the study is composed by 277 objects.
