- ID:
- ivo://CDS.VizieR/J/PASP/117/676
- Title:
- LHS faint proper-motion stars
- Short Name:
- J/PASP/117/676
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present low-resolution spectroscopic observations of faint proper-motion stars from the LHS Catalogue, concentrating on stars with m_r_>16.5 and {mu}>0.5"/yr. The present paper includes observations and spectral classifications for 294 M dwarfs, M subdwarfs (sdM), and extreme M subdwarfs (esdM). We also identify white dwarfs among the faintest LHS stars. We have cross-referenced this sample against the Two Micron All Sky Survey (2MASS) sources, and list data for the detected objects. We discuss stars of individual interest, as well as the characteristics of the overall sample. As expected, a significant number of the stars in this proper-motion-selected sample are halo subdwarfs, including an esdM dwarf, LHS 3481, that is likely to lie within 20pc of the Sun. None of the subdwarfs show H{alpha} emission.
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1192. LH 47 UVBRI photometry
- ID:
- ivo://CDS.VizieR/J/A+AS/123/455
- Title:
- LH 47 UVBRI photometry
- Short Name:
- J/A+AS/123/455
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 3 lists the final photometric data of our observations. The UBVRI observations were done with the 1.54m Danish telescope at ESO on October 3rd and 4th, 1992. The CCD was ESO#28, a TEK 1024x1024 with a pixel size of 24mue corresponding to 0.377" per pixel. The total field of view is 6.4'x6.4'. A standard reduction was done with MIDAS and IRAF, the photometry was performed with DAOPHOT within IRAF. The images of Oct 4th have been calibrated using the calibration field around PG 0231+051 (Landolt 1992, Cat. <II/183>). The images of Oct 3rd have then been adopted to the system of Oct 4th. The final Table 3 lists 4613 stars with V and B-V information. In addition U-B is available for 1159 of these stars, V-R for 3519 and V-I for 2854 stars. Table 4 gives those stars from our field of view which are present in the MACS (Magellanic Catalogue of Stars; Tucholke et al. 1996, Cat. <I/221>). The table contains the MACS Id., our x and y position and our UBV photometry, and right ascension and declination from the MACS. These stars may serve to calculate an exact position for every star from Table 3 or to define a coordinate grid for comparison with other observations, such as radio or X-ray data.
- ID:
- ivo://CDS.VizieR/J/AJ/160/155
- Title:
- Light curve segments of 22 host stars with TESS
- Short Name:
- J/AJ/160/155
- Date:
- 10 Dec 2021
- Publisher:
- CDS
- Description:
- We present a systematic phase curve analysis of known transiting systems observed by the Transiting Exoplanet Survey Satellite (TESS) during year one of the primary mission. Using theoretical predictions for the amplitude of the planetary longitudinal atmospheric brightness modulation, stellar ellipsoidal distortion and Doppler boosting, as well as brightness considerations to select targets with likely detectable signals, we applied a uniform data processing and light-curve modeling framework to fit the full-orbit phase curves of 22 transiting systems with planet-mass or brown dwarf companions, including previously published systems. Statistically significant secondary eclipse depths and/or atmospheric brightness modulation amplitudes were measured for HIP65A, WASP-18, WASP-19, WASP-72, WASP-100, WASP-111, WASP-121, and WASP-122/KELT-14. For WASP-100b, we found marginal evidence that the brightest region of the atmosphere is shifted eastward away from the substellar point. We detected significant ellipsoidal distortion signals in the light curves of HIP65A, TOI-503, WASP-18, and WASP-30, with HIP65A, TOI-503 and WASP-18 also exhibiting Doppler boosting. The measured amplitudes of these signals agree with the predictions of theoretical models. Combining the optical secondary eclipse depths with previously published Spitzer 3.6 and 4.5{mu}m measurements, we derived dayside brightness temperatures and visible-light geometric albedos for a subset of the analyzed systems. We also calculated updated transit ephemerides combining the transit timings from the TESS light curves with previous literature values.
- ID:
- ivo://CDS.VizieR/J/AJ/148/126
- Title:
- Light curves of four overcontact binaries
- Short Name:
- J/AJ/148/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze new, high quality multicolor light curves of four overcontact binaries: AK Her, HI Dra, V1128 Tau, and V2612 Oph, and determine their orbital and physical parameters using the modeling program of G. Djurasevic and recently published results of radial velocity studies. The achieved precision in absolute masses is between 10% and 20%, and the precision in absolute radii is between 5% and 10%. All four systems are W UMa-type binaries with bright or dark spots indicative of mass and energy transfer or surface activity. We estimate the distances and the ages of the systems using the luminosities computed through our analysis, and perform an O-C study for V1128 Tau, which reveals a complex period variation that can be interpreted in terms of mass loss/exchange and either the presence of the third body, or the magnetic activity on one of the components. We conclude that further observations of these systems are needed to deepen our understanding of their nature and variability.
- ID:
- ivo://CDS.VizieR/J/ApJ/819/35
- Title:
- Light curves of four transients from PTF & SNLS
- Short Name:
- J/ApJ/819/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations of four rapidly rising (t_rise_~10days) transients with peak luminosities between those of supernovae (SNe) and superluminous SNe (M_peak_~-20) --one discovered and followed by the Palomar Transient Factory (PTF) and three by the Supernova Legacy Survey (SNLS). The light curves resemble those of SN 2011kl, recently shown to be associated with an ultra-long-duration gamma-ray burst (GRB), though no GRB was seen to accompany our SNe. The rapid rise to a luminous peak places these events in a unique part of SN phase space, challenging standard SN emission mechanisms. Spectra of the PTF event formally classify it as an SN II due to broad H{alpha} emission, but an unusual absorption feature, which can be interpreted as either high velocity H{alpha} (though deeper than in previously known cases) or SiII (as seen in SNe Ia), is also observed. We find that existing models of white dwarf detonations, CSM interaction, shock breakout in a wind (or steeper CSM), and magnetar spin down cannot readily explain the observations. We consider the possibility that a "Type 1.5 SN" scenario could be the origin of our events.
- ID:
- ivo://CDS.VizieR/J/AJ/145/60
- Title:
- Light curves of GN Boo, BL Leo, and V1918 Cyg
- Short Name:
- J/AJ/145/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new photometry for three short-period contact binaries, GN Boo, BL Leo, and V1918 Cyg, observed from 2008 December to 2012 April using several small telescopes in China. Photometric models were deduced from new observations using the updated Wilson-Devinney Code. The results show that GN Boo and BL Leo are W-type contact binaries, while V1918 Cyg is an A-type one. The mass ratios and fill-out factors are q=0.320(+/-0.002) and f=5.8(+/-0.1)% for GN Boo, q=0.476(+/-0.005) and f=21.3(+/-1.1)% for BL Leo, q=0.264(+/-0.002), and f=49.7(+/-0.7)% for V1918 Cyg, respectively. From the (O-C) curves, it is discovered that the orbital periods of three binaries have varied in a complicated way, i.e., cyclic oscillation for GN Boo, long-term period decrease for BL Leo, and both for V1918 Cyg. The cyclic variations for GN Boo and V1918 Cyg may probably be attributed to the magnetic activity of the primary component or light-time effect due to the third body. Meanwhile, the secular period decreases for BL Leo and V1918 Cyg may result from mass transfer from the primary to the secondary, accompanying the mass and angular momentum loss from the central system. Finally, GN Boo, BL Leo, and V1918 Cyg will evolve into deep contact binaries. Additionally, a statistical study of 37 contact binaries with decreasing periods is given. We obtained the relations of q-f and q-dlnP/dt, and preliminarily determined the mass loss rate of dln M/dt from the binary system.
- ID:
- ivo://CDS.VizieR/J/AJ/145/80
- Title:
- Light curves of HS Aqr, EG Cep, VW LMi, DU Boo
- Short Name:
- J/AJ/145/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze new multicolor light curves for four close late-type binaries: HS Aqr, EG Cep, VW LMi, and DU Boo, in order to determine the orbital and physical parameters of the systems and estimate the distances. The analysis is done using the modeling code of G. Djurasevic, and is based on up-to-date measurements of spectroscopic elements. All four systems have complex, asymmetric light curves that we model by including bright or dark spots on one or both components. Our findings indicate that HS Aqr and EG Cep are in semi-detached, while VW LMi and DU Boo are in overcontact configurations.
- ID:
- ivo://CDS.VizieR/J/ApJ/741/97
- Title:
- Light curves of Ibc supernovae
- Short Name:
- J/ApJ/741/97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present detailed optical photometry for 25 Type Ibc supernovae (SNe Ibc) within d~150Mpc obtained with the robotic Palomar 60 inch telescope in 2004-2007. This study represents the first uniform, systematic, and statistical sample of multi-band SNe Ibc light curves available to date. We correct the light curves for host galaxy extinction using a new technique based on the photometric color evolution, namely, we show that the (V-R) color of extinction-corrected SNe Ibc at {Delta}t~10days after V-band maximum is tightly distributed, <(V-R)_V10_>=0.26+/-0.06mag. Using this technique, we find that SNe Ibc typically suffer from significant host galaxy extinction, <E(B-V)>~0.4mag. A comparison of the extinction-corrected light curves for helium-rich (Type Ib) and helium-poor (Type Ic) SNe reveals that they are statistically indistinguishable, both in luminosity and decline rate. We report peak absolute magnitudes of <M_R_>=-17.9+/-0.9 mag and <M_R_>=-18.3+/-0.6mag for SNe Ib and Ic, respectively.
- ID:
- ivo://CDS.VizieR/J/ApJS/219/25
- Title:
- Light curves of RR Lyrae stars in M3 (NGC5272)
- Short Name:
- J/ApJS/219/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The overtone and multi-mode RR Lyrae stars in the globular cluster M3 are studied using a 200 day long, B,V, and l_c_ time-series photometry obtained in 2012. 70% of the 52 overtone variables observed show some kind of multi-periodicity (with additional frequency at f_0.61_=f_1O_/0.61 frequency ratio, Blazhko effect, double/multi-mode pulsation, and period doubling). A signal at the 0.587 frequency ratio to the fundamental-mode frequency is detected in the double-mode star, V13, which may be identified as the second radial overtone mode. If this mode identification is correct, then V13 is the first RR Lyrae star showing triple-mode pulsation of the first three radial modes. Either the Blazhko effect or the f_0,61_ frequency (or both of these phenomena) appears in seven double-mode stars. The P_1O_/P_F_ period ratio of RRd stars showing the Blazhko effect are anomalous. A displacement of the main frequency component at the fundamental mode with the value of modulation frequency (or its half), is detected in three Blazhko RRd stars that are parallel with the appearance of the overtone-mode pulsation. The f_0.61_ frequency appears in RRc stars that lie at the blue side of the double-mode region and in RRd stars, raising the suspicion that its occurrence may be connected to double-mode pulsation. The changes of the Blazhko and double-mode properties of the stars are also reviewed using the recent and archive photometric data.
- ID:
- ivo://CDS.VizieR/J/MNRAS/478/4590
- Title:
- Light curves of RR Lyrae variables in M31
- Short Name:
- J/MNRAS/478/4590
- Date:
- 10 Dec 2021 13:45:59
- Publisher:
- CDS
- Description:
- We present an analysis of M31 RR Lyrae stars in six different fields using archival imaging from the Hubble Space Telescope. Published data for M31, M33, and several M31 dwarf spheroidal galaxies are also used to study the global properties of RR Lyrae in these systems. From the properties of RR Lyrae stars, we found that the majority of M31 and M33 RRLs are of Oosterhoff I (OoI),while those in M31 dSphs are of Oosterhoff intermediate. The main parameter affecting these Oosterhoff types is likely to be metallicity. Metallicity also plays a role in the lack of RRLs in the high amplitude short period(HASP, defined as those with P<=0.48 and A_V_>=0.75mag) variables in M31 dSphs. This difference in the properties of RRLs between their parent galaxy and satellites, as well as the lack of RRLs in the HASP region in dSphs can also be observed in the Milky Way (MW). Therefore, systems like these dSphs are unlikely to be the main building blocks of the M31 and MW halo.