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2041. Photometry of M giant candidates in the Milky Way
ID:
ivo://CDS.VizieR/J/AJ/147/76
Title:
Photometry of M giant candidates in the Milky Way
Short Name:
J/AJ/147/76
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalog of 404 M giant candidates found in the UKIRT Infrared Deep Sky Survey (UKIDSS). The 2400deg^2^ available in the UKIDSS Large Area Survey Data Release 8 resolve M giants through a volume four times larger than that of the entire Two Micron All Sky Survey. Combining near-infrared photometry with optical photometry and proper motions from the Sloan Digital Sky Survey yields an M giant candidate catalog with less M dwarf and quasar contamination than previous searches for similarly distant M giants. Extensive follow-up spectroscopy of this sample will yield the first map of our Galaxy's outermost reaches over a large area of sky. Our initial spectroscopic follow-up of ~30 bright candidates yielded the positive identification of five M giants at distances ~20-90kpc. Each of these confirmed M giants have positions and velocities consistent with the Sagittarius stream. The fainter M giant candidates in our sample have estimated photometric distances ~200kpc (assuming [Fe/H]=0.0), but require further spectroscopic verification. The photometric distance estimates extend beyond the Milky Way's virial radius, and increase by ~50% for each 0.5dex decrease in assumed [Fe/H]. Given the number of M giant candidates, initial selection efficiency, and volume surveyed, we loosely estimate that at least one additional Sagittarius-like accretion event could have contributed to the hierarchical build-up of the Milky Way's outer halo.
2042. Photometry of multiples at NAOR and ASV in 2012
ID:
ivo://CDS.VizieR/J/AJ/149/150
Title:
Photometry of multiples at NAOR and ASV in 2012
Short Name:
J/AJ/149/150
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the 2m telescope of the Bulgarian National Astronomical Observatory at Rozhen, observations of 246 double or multiple stars were carried out during six nights in 2012. This is the seventh series of measurements of CCD frames of double and multiple stars obtained at Rozhen. Also in 2012, using the 0.6m telescope of the Serbian Astronomical Station on the mountain of Vidojevica, observations of 117 double or multiple stars were carried out during five nights. This is the second series of measurements of CCD frames of double and multiple stars obtained at this station. In this paper we present the results for the position angle and angular separation for 453 pairs and residuals for 105 pairs with published orbital elements or linear solutions. These observations have angular separations in the range from 1.50'' to 178.12'', with a median angular separation of 8.13''. We also present the recalculated linear solution for one pair and three linear solutions that have been calculated for the first time.
2043. Photometry of orange-red CaI triplet in Late-Type Stars
ID:
ivo://CDS.VizieR/II/25
Title:
Photometry of orange-red CaI triplet in Late-Type Stars
Short Name:
II/25
Date:
21 Oct 2021
Publisher:
CDS
Description:
Calcium absorption lines were measured using narrow-band photometry on 296 high and low velocity G8-K5 stars of all luminosity classes. Because the blue-violet region of the stellar spectra is too crowded for narrow-band photometry, this investigation of abundance involved measurements of the orange-red CaI triplet 4(3)P-5(3)S, with wavelengths 6102.7, 6122.2 and 6162.2{AA}. "Calcium triplet ratio" is defined as "the measured light intensity ratios, comparison/central regions, calibrated in terms of a standard lamp as described in previous Cambridge papers". The catalog (table I of paper) includes HD number, (B-V) color index, Mg b ratio, H{alpha} ratio, Calcium triplet ratio, and a running number.
2044. Photometry of polar CV* 1RXS J173006.4+033813
ID:
ivo://CDS.VizieR/J/ApJ/721/412
Title:
Photometry of polar CV* 1RXS J173006.4+033813
Short Name:
J/ApJ/721/412
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the discovery of 1RXS J173006.4+033813, a polar cataclysmic variable with a period of 120.21 minutes. The white dwarf primary has a magnetic field of B=42^+6^_-5_MG and the secondary is an M3 dwarf. The system shows highly symmetric double-peaked photometric modulation in the active state as well as in quiescence. These arise from a combination of cyclotron beaming and ellipsoidal modulation. The projected orbital velocity of the secondary is K_2_=390+/-4km/s. We place an upper limit of 830+/-65pc on the distance.
2045. Photometry of RR Lyrae candidates in Virgo stream
ID:
ivo://CDS.VizieR/J/ApJ/691/306
Title:
Photometry of RR Lyrae candidates in Virgo stream
Short Name:
J/ApJ/691/306
Date:
21 Oct 2021
Publisher:
CDS
Description:
A subset of the RR Lyrae (RRL) candidates identified from the Southern Edgeworth-Kuiper Belt Object (SEKBO) survey data have been followed up photometrically (n=106) and spectroscopically (n=51). Period and light curve fitting reveals a 24+/-7% contamination of SEKBO survey data by non-RRLs. This paper focuses on the region of the Virgo Stellar Stream (VSS), particularly on its extension to the south of the declination limits of the Sloan Digital Sky Survey and of the Quasar Equatorial Survey Team (QUEST) RRL survey.
2046. Photometry of SN 2009bb
ID:
ivo://CDS.VizieR/J/ApJ/728/14
Title:
Photometry of SN 2009bb
Short Name:
J/ApJ/728/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudobolometric light curve of SN 2009bb suggests that 4.1+/-1.9M_{sun}_ of material was ejected with 0.22+/-0.06M_{sun} of it being ^56^Ni. The resulting kinetic energy is 1.8+/-0.7x10^52^erg. This, together with an absolute peak magnitude of M_B_=-18.36+/-0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission and high metallicity of its environment makes SN 2009bb a peculiar object. Similar to the case for gamma-ray bursts (GRBs), we find that the bulk explosion parameters of SN 2009bb cannot account for the copious energy coupled to relativistic ejecta, and conclude that another energy reservoir (a central engine) is required to power the radio emission. Nevertheless, the analysis of the SN 2009bb nebular spectrum suggests that the failed GRB detection is not imputable to a large angle between the line-of-sight and the GRB beamed radiation. Therefore, if a GRB was produced during the SN 2009bb explosion, it was below the threshold of the current generation of {gamma}-ray instruments.
2047. Photometry of SN 2013gh and iPTF13dge
ID:
ivo://CDS.VizieR/J/A+A/592/A40
Title:
Photometry of SN 2013gh and iPTF13dge
Short Name:
J/A+A/592/A40
Date:
21 Oct 2021
Publisher:
CDS
Description:
Temporal variability of narrow absorption lines in high-resolution spectra of Type Ia supernovae (SNe Ia) is studied to search for circumstellar matter. Time series which resolve the profiles of absorption lines such as NaI D or CaII H&K are expected to reveal variations due to photoionisation and subsequent recombination of the gases. The presence, composition, and geometry of circumstellar matter may hint at the elusive progenitor system of SNe Ia and could also affect the observed reddening law. To date, there are few known cases of time-varying NaI D absorption in SNe Ia, all of which occurred during relatively late phases of the supernova (SN) evolution. Photoionisation, however, is predicted to occur during the early phases of SNe Ia, when the supernovae peak in the ultraviolet. We attempt, therefore, to observe early-time absorption-line variations by obtaining high-resolution spectra of SNe before maximum light We have obtained photometry and high-resolution spectroscopy of SNe Ia 2013gh and iPTF 13dge, to search for absorption- line variations. Furthermore, we study interstellar absorption features in relation to the observed photometric colours of the SNe. Results. Both SNe display deep NaI D and CaII H&K absorption features. Furthermore, small but significant variations are detected in a feature of the NaI D profile of SN 2013gh. The variations are consistent with either geometric effects of rapidly moving or patchy gas clouds or photoionisation of NaI gas at R~=10^19^cm from the explosion. Our analysis indicates that it is necessary to focus on early phases to detect photoionisation effects of gases in the circumstellar medium of SNe Ia. Different absorbers such as NaI and CaII can be used to probe for matter at different distances from the SNe. The nondetection of variations during early phases makes it possible to put limits on the abundance of the species at those distances.
2048. Photometry of southern NLTT stars
ID:
ivo://CDS.VizieR/J/AJ/123/2822
Title:
Photometry of southern NLTT stars
Short Name:
J/AJ/123/2822
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present BVRI photometry of 180 bright, southern nearby-star candidates. The stars were selected from the New Luyten Two-Tenths proper-motion catalog (Cat. <I/98>) based on optical/infrared colors, constructed by combining Luyten's m_r_ estimates with near-infrared photometry from the Two Micron All Sky Survey (Cat. <B/2mass>) . Photometric parallaxes derived from V-Ks, V-I, and I-J colors, combined with the limited available astrometry, show that as many as 108 stars may lie within 20pc of the Sun. Of these, 53 are new to nearby-star catalogs, including three within 10pc of the Sun.
2049. Photometry of star clusters in NGC 1380
ID:
ivo://CDS.VizieR/J/A+A/467/1003
Title:
Photometry of star clusters in NGC 1380
Short Name:
J/A+A/467/1003
Date:
21 Oct 2021
Publisher:
CDS
Description:
NGC 1380 is a lenticular galaxy located near the center of the Fornax Cluster, northeast of NGC 1399. The globular cluster system of this galaxy was previously studied only from the ground. Recent studies of similar early-type galaxies, specially lenticular ones, reveal the existence of star clusters that apparently break up the traditional open/globular cluster dichotomy. With higher quality photometry from HST/WFPC2 we study the star clusters in NGC 1380, measuring their magnitudes, colours, sizes and projected distances from the center of the galaxy. We used deep archival HST/WFPC2 in the B and V bands. We built colour magnitude diagrams from which we selected a sample of cluster candidates. We also analysed their colour distribution and measured their sizes. Based on their location in the luminosity-size diagram we estimated probabilities of them being typical globular clusters as those found in the Galaxy. A total of about 570 cluster candidates were found down to V=26.5. We measured sizes for approximately 200 of them. The observed colour distribution has three apparent peaks. Likewise for the size distribution. We identified the smaller population as being mainly typical globular clusters, while the more extended objects have small probabilities of being such objects. Different correlations between absolute magnitudes, sizes, colours and location were inferred for these cluster sub-populations. Most extended clusters (Reff>4pc) share similar properties to the diffuse star clusters reported to inhabit luminous early-type galaxies in the Virgo galaxy cluster such as being of low surface brightness and fainter than MV~-8. We also report on a small group of (R_eff_~10pc), -8<MV<-6, red clusters located near the centre of NGC 1380, which may be interpreted as faint fuzzies.
2050. Photometry of stars at NAOR and ASV in 2013-2014
ID:
ivo://CDS.VizieR/J/AJ/151/58
Title:
Photometry of stars at NAOR and ASV in 2013-2014
Short Name:
J/AJ/151/58
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the 2m telescope of the Bulgarian National Astronomical Observatory at Rozhen, observations of 271 double or multiple stars were carried out during seven nights in 2013 and 2014. This is the eighth series of measurements of CCD frames of double and multiple stars obtained at Rozhen. Also in 2013 and 2014, using the 0.6m telescope of the Serbian Astronomical Station on the mountain of Vidojevica, observations of 343 double or multiple stars were carried out during 21 nights. This is the third series of measurements of CCD frames of double and multiple stars obtained at this station. In this paper, we present the results for the position angle and angular separation for 721 pairs and residuals for 126 pairs with published orbital elements or linear solutions. These observations have angular separations in the range from 1.24'' to 202.30'', with a median angular separation of 7.17''. We also present eight linear solutions that have been calculated for the first time.