- ID:
- ivo://CDS.VizieR/J/A+A/304/406
- Title:
- Photometry and radial velocities of 16 Lac
- Short Name:
- J/A+A/304/406
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric and spectroscopic observations of the {beta} Cephei star 16 Lacertae obtained in 1983 and 1984 are presented and analysed. Using all the published maxima we have computed ephemerides for each of the three pulsational modes. No period variation is detected from 1950 to 1983. In order to identify the pulsational modes corresponding to the three main periods of 16 Lac we have applied different methods based on photometric and radial velocity variations. All give the same results: the mode corresponding to the largest amplitude P_1_ (016917d) is radial, P_2_ (017079d) is a nonradial mode of degree l=2. For P_3_ (018171d) the results are more dubious, but P_3_ is probably a l=1 nonradial mode. We have also studied the interaction between pulsation and binarity in 16 Lac. We confirm the existence of a resonance phenomenon between the radial and nonradial modes: the ratios between the beat frequencies of the pulsational modes and the orbital frequency are close but significantly different from simple rational numbers. According to Kato (1974) that means that the nonradial modes might be excited or at least enhanced by tidal effects. They would have been selected among all the possible modes because their ability to be resonant with the radial mode. The photometric amplitude of P_3_ in both filters appears to be variable from night to night in correlation with the orbital phase but despite its rapid and irregular fluctuations, the P_3_ amplitude stayed in constant average over 80 years. The present observations confirm the decrease of P_1_ and P_2_ amplitudes since 1950 but an analysis of older radial velocity data shows that the amplitude of the P_1_ mode went through a maximum around the middle of the century before the observed decrease of the last thirty years.
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- ID:
- ivo://CDS.VizieR/J/A+A/498/L5
- Title:
- Photometry and spectroscopy of HD 80606b
- Short Name:
- J/A+A/498/L5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the detection of the primary transit of the extra-solar planet HD80606b, thanks to photometric and spectroscopic observations performed at the Observatoire de Haute-Provence, simultaneously with the CCD camera at the 120-cm telescope and the SOPHIE spectrograph on the 193-cm telescope. We observed the whole egress of the transit and partially its central part, in both datasets with the same timings.
- ID:
- ivo://CDS.VizieR/J/A+A/516/A95
- Title:
- Photometry and spectroscopy of HD 80606b
- Short Name:
- J/A+A/516/A95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new observations of a transit of the 111.4-day-period exoplanet HD80606b. Due to this long orbital period and to the orientation of the eccentric orbit (e=0.9), the HD80606b's transits last for about 12 hours. This makes practically impossible the observation of a full transit from a given ground-based observatory. Using the Spitzer Space Telescope and its IRAC camera on the post-cryogenic mission, we performed a 19-hour-long photometric observation of HD80606 that covers the full transit of 13-14 January 2010 as well as off-transit references immediately before and after the event. We complement this photometric data by new spectroscopic observations that we simultaneously performed with SOPHIE at Haute-Provence Observatory. This provides radial velocity measurements of the first half of the transit that was previously uncovered with spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+A/607/A127
- Title:
- 2014-2017 photometry for ASASSN-13db
- Short Name:
- J/A+A/607/A127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accretion outbursts are key elements in star formation. ASASSN-13db is a M5-type star with a protoplanetary disk, the lowest-mass star known to experience accretion outbursts. Since its discovery in 2013, it has experienced two outbursts, the second of which started in November 2014 and lasted until February 2017. We explore the photometric and spectroscopic behavior of ASASSN-13db during the 2014-2017 outburst. We use high- and low-resolution spectroscopy and time-resolved photometry from the ASAS-SN survey, the LCOGT and the Beacon Observatory to study the lightcurve of ASASSN-13db and the dynamical and physical properties of the accretion flow. Results. The 2014-2017 outburst lasted for nearly 800 days. A 4.15d period in the light curve likely corresponds to rotational modulation of a star with hot spot(s). The spectra show multiple emission lines with variable inverse P-Cygni profiles and a highly variable blue-shifted absorption below the continuum. Line ratios from metallic emission lines (FeI/FeII, TiI/TiII) suggest temperatures of ~5800-6000K in the accretion flow.
- ID:
- ivo://CDS.VizieR/J/AJ/130/1640
- Title:
- Photometry of candidate RR Lyrae stars in the SDSS
- Short Name:
- J/AJ/130/1640
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present unfiltered CCD photometry of a sample of 71 candidate RR Lyrae stars during 2003 and 2004, out of 148 candidate stars that were selected from Sloan Digital Sky Survey (SDSS) commissioning data by Ivezic and coworkers (2000AJ....120..963I). We obtain light curves of 69 candidate stars and present a catalog of their positions, amplitudes, periods, types, and mean magnitudes. We confirm that the 69 stars are true RR Lyrae variables based on periods and light curves, for the first time for 41 of them. We identify 57 type ab, 11 type c, and 1 type d (double-mode) in our sample. The double-mode RR Lyrae star shows properties similar to globular cluster stars and are unlike field stars of the Galactic halo in the Petersen diagram.
- ID:
- ivo://CDS.VizieR/J/ApJS/117/135
- Title:
- Photometry of Cepheids in Magellanic Clouds
- Short Name:
- J/ApJS/117/135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report BV(RI)C data for a select group of 14 Cepheids in the Large Magellanic Cloud and eight in the Small Magellanic Cloud that have preexisting radial velocity curves. The photometry was obtained as part of a program to determine distances to these Cepheids by means of the visual surface brightness technique and to improve significantly the optical BV(RI)C light curves of Magellanic Cloud Cepheids. The data were acquired on the 0.9 m telescope at Cerro Tololo Inter-American Observatory with the CFCCD instrument and with the 1 m photometric telescope at ESO using aperture photometry. The median number of measures per Cepheid is 46 in each band, and the uncertainty in the photometry is typically 0.01 mag. Using these data together with data from the literature, we determined improved periods for all variables. For most of the Cepheids, these revised periods lead to excellent, low-noise light curves, but for a few variables, the periods are obviously variable.
- ID:
- ivo://CDS.VizieR/J/A+A/602/A99
- Title:
- Photometry of EXors from Asiago plates
- Short Name:
- J/A+A/602/A99
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- EXor objects are young variables that show episodic variations of brightness commonly associated to enhanced accretion outbursts. With the aim of investigating the long-term photometric behaviour of a few EXor sources, we present here data from the archival plates of the Asiago Observatory, showing the Orion field where the three EXors V1118, V1143, and NY are located. A total of 484 plates were investigated, providing a total of more than 1000 magnitudes for the three stars, which cover a period of about 35yrs between 1959 to 1993. We then compared our data with literature data. Apart from a newly discovered flare-up of V1118, we identify the same outbursts already known, but we provide two added values: (i) a long-term sampling of the quiescence phase; and (ii) repeated multi-colour observations (BVRI bands). The former allows us to give a reliable characterisation of the quiescence, which represents a unique reference for studies that will analyze future outbursts and the physical changes induced by these events. The latter is useful for confirming whether the intermittent increases of brightness are accretion-driven (as in the case of V1118), or extinction-driven (as in the case of V1143). Accordingly, doubts arise about the V1143 classification as a pure EXor object. Finally, although our plates do not separate NY Ori and the star very close to it, they indicate that this EXor did not undergo any major outbursts during our 40yrs of monitoring.
- ID:
- ivo://CDS.VizieR/J/A+A/374/1049
- Title:
- Photometry of FK Com for 1993-2001
- Short Name:
- J/A+A/374/1049
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report 8 years of previously unpublished photometric observations of FK Com. The observations have been carried out between 1993 and 2001 with six different telescopes: 60 cm at Mt. Maidanak (Tashkent, Uzbekistan), Phoenix 10, Wolfgang and Amadeus located in Arizona, USA, and 20cm and 60 cm KVA on La Palma, Spain. Observations contain measurements at the following bands: Johnson U, B, V and R, Bessel R, Cousins I and Stromgren b and y. The observations are differential photometry in respect to the primary comparison star HD 117567. NOTE: Table 1 in the paper contains some small misprints in the Julian dates. Also for Wolfgang and Amadeus the number of observations given in Table1 at each band is slightly less than actually given in Table2c and Table2d. This is caused by accidentally using a limiting error of 0.01 in magnitudes when creating Table 1. In Table 2 the limiting error for Wolfgang and Amadeus is 0.02 mag, as mentioned in the paper itself. In Table2a-e 99.0000 means that no observations were available at that time at that band or that the error in the magnitude was larger than 0.02.
- ID:
- ivo://CDS.VizieR/J/A+AS/106/141
- Title:
- Photometry of luminous blue variables
- Short Name:
- J/A+AS/106/141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An extensive photometric dataset has been compiled for six Luminous Blue Variables (LBVs). The dataset comprises published and unpublished measurements in the Stroemgren, Geneva and Walraven photometric systems. The measurements within each individual system are presented in a uniform manner. Combining observations from these three photometric systems, a VJ light curve has been constructed for each LBV. Examination of the light curves reveals variations on widely different magnitude and time scales. For explanation about the photometric sytems, see the definitions in the General Catalogue of Photometric Data: about uvby (Stroemgren) <GCPD/04> ; Geneva <GCPD/13> ; Walraven VBLUW <GCPD/11>
- ID:
- ivo://CDS.VizieR/J/AJ/133/11
- Title:
- Photometry of OGLE-TR 111
- Short Name:
- J/AJ/133/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of our ongoing effort to measure exoplanet sizes and transit times with greater accuracy, we present I-band observations of two transits of OGLE-TR-111b.
