- 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.
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- ID:
- ivo://CDS.VizieR/J/PAZh/35/592
- Title:
- Photometry of FG Sge at the ejection state
- Short Name:
- J/PAZh/35/592
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New photometric observations of the variable star FG Sge, a rapidly evolving planetary nebula nucleus, were performed in 2003-2008. On 230 nights, we obtained 86 UBV and 155 BVRI (or Rc, Ic) magnitude estimates. The maximum amplitude of the V-band light variations was >8mag. Six deep minima and four high maxima were observed.
- 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- We report 8 years of previously unpublished photometric observations of FK Com.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/ApJ/742/116
- Title:
- Photometry of four massive transiting exoplanets
- Short Name:
- J/ApJ/742/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of four relatively massive (2-7M_J_) transiting extrasolar planets. HAT-P-20b orbits the moderately bright V=11.339 K3 dwarf star GSC 1910-00239 on a circular orbit, with a period P=2.875317+/-0.000004 days. The planetary companion has a mass of 7.246+/-0.187M_J_ and a radius of 0.867+/-0.033R_J_ yielding a mean density of 13.78+/-1.50g/cm^3^. HAT-P-21b orbits the V=11.685 G3 dwarf star GSC 3013-01229 on an eccentric (e=0.228+/-0.016) orbit, with a period P=4.124481+/-0.000007 days. The planetary companion has a mass of 4.063+/-0.161M_J_ and a radius of 1.024+/-0.092R_J_ yielding a mean density of 4.68^+1.59^_-0.99_g/cm^3^. HAT-P-21b is a borderline object between the pM and pL class planets, and the transits occur near apastron. HAT-P-22b orbits the bright V=9.732 G5 dwarf star HD 233731 on a circular orbit, with a period P=3.212220+/-0.000009 days. The planet has a mass of 2.147+/-0.061M_J_ and a compact radius of 1.080+/-0.058R_J_ yielding a mean density of 2.11^+0.40^_-0.29_g/cm^3^. The host star also harbors an M-dwarf companion at a wide separation. Finally, HAT-P-23b orbits the V=12.432 G0 dwarf star GSC 1632-01396 on a close to circular orbit, with a period P=1.212884+/-0.000002 days. The planetary companion has a mass of 2.090+/-0.111M_J_ and a radius of 1.368+/-0.090R_J_ yielding a mean density of 1.01+/-0.18g/cm^3^. HAT-P-23b is an inflated and massive hot Jupiter on a very short period orbit, and has one of the shortest characteristic infall times (7.5^+2.9^_-1.8_Myr) before it gets engulfed by the star.
- ID:
- ivo://CDS.VizieR/J/ApJ/779/65
- Title:
- Photometry of LBGs, LAEs and GNBs at z~2.85
- Short Name:
- J/ApJ/779/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a survey for z~2.85 Lyman-continuum (LyC) emission in the HS1549+1933 field and place constraints on the amount of ionizing radiation escaping from star-forming galaxies. Using a custom narrowband filter (NB3420) tuned to wavelengths just below the Lyman limit at z>=2.82, we probe the LyC spectral region of 49 Lyman break galaxies (LBGs) and 91 Ly{alpha} emitters (LAEs) spectroscopically confirmed at z>=2.82. Four LBGs and seven LAEs are detected in NB3420. Using V-band data probing the rest-frame nonionizing UV, we observe that many NB3420-detected galaxies exhibit spatial offsets between their LyC and nonionizing UV emission and are characterized by extremely blue NB3420-V colors, corresponding to low ratios of nonionizing to ionizing radiation (F_UV_/F_LyC_) that are in tension with current stellar population synthesis models. We measure average values of (F_UV_/F_LyC_) for our LBG and LAE samples, correcting for foreground galaxy contamination and H I absorption in the intergalactic medium. We find (F_UV_/F_LyC_)_corr_^LBG^=82+/-45 and (F_UV_/F_LyC_)_corr_^LAE^=7.4+/-3.6. These flux density ratios correspond, respectively, to relative LyC escape fractions of f_esc,rel_^LBG^=5%-8%, and f_esc,rel_^LAE^=18%-49% absolute LyC escape fractions of f_esc,rel_^LBG^=1%-2% and f_esc,rel_^LAE^=5%-15%, and a comoving LyC emissivity from star-forming galaxies of 8.8-15.0x10^24^ erg/s/Hz/Mpc^3^. In order to study the differential properties of galaxies with and without LyC detections, we analyze narrowband Ly{alpha} imaging and rest-frame near-infrared imaging, finding that while LAEs with LyC detections have lower Ly{alpha} equivalent widths on average, there is no substantial difference in the rest-frame near-infrared colors of LBGs or LAEs with and without LyC detections. These preliminary results are consistent with an orientation-dependent model where LyC emission escapes through cleared paths in a patchy interstellar medium.
- 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/119/2214
- Title:
- Photometry of Magellanic OB associations
- Short Name:
- J/AJ/119/2214
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine new CCD UBV photometry and spectroscopy with those from the literature to investigate 19 Magellanic Cloud OB associations that contain Wolf-Rayet (W-R) and other types of evolved, massive stars. Our spectroscopy reveals a wealth of newly identified interesting objects, including early O-type supergiants, a high-mass, double-lined binary in the SMC, and, in the LMC, a newly confirmed luminous blue variable (LBV; R85), a newly discovered W-R star (Sk -69^deg^ 194), and a newly found luminous B[e] star (LH 85-10). We use these data to provide precise reddening determinations and construct physical H-R diagrams for the associations.
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/153/195
- Title:
- Photometry of multiple stars at NAOR&ASV in 2015
- Short Name:
- J/AJ/153/195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of CCD observations of 154 double or multiple stars, made with the 2 m telescope of the Bulgarian National Astronomical Observatory at Rozhen over five nights in 2015, are presented. This is the ninth series of measurements of CCD frames obtained at Rozhen. We also present results of CCD observations of 323 double or multiple stars made with the 0.6 m telescope of the Serbian Astronomical Station on the mountain of Vidojevica over 23 nights in 2015. This is the fourth series of measurements of CCD frames obtained at this station. This paper contains the results for the position angle and angular separation for 801 pairs and residuals for 127 pairs with published orbital elements or linear solutions. The angular separations are in the range from 1.52" to 201.56", with a median angular separation of 8.26". We also present eight pairs that are measured for the first time and linear elements for five pairs.
1190. Photometry of NGC 2808
- ID:
- ivo://CDS.VizieR/J/A+AS/84/59
- Title:
- Photometry of NGC 2808
- Short Name:
- J/A+AS/84/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
