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Photometry of symbiotic stars. XI. EG And, Z And, BF Cyg, CH Cyg, CI Cyg, V1329 Cyg, TX CVn, AG Dra, RW Hya, AR Pav, AG Peg, AX Per, QW Sge, IV Vir and the LMXB V934 Her
We present new photometric observations of EG And, Z And, BF Cyg, CHCyg, CI Cyg, V1329 Cyg, TX CVn, AG Dra, RW Hya, AG Peg, AX Per, IV Virand the peculiar M giant V934 Her, which were made in the standardJohnson UBV(R) system. QW Sge was measured in the Kron-Cousin B, V,RC, IC system and for AR Pav we present its newvisual estimates. The current issue gathers observations of theseobjects to December 2003. The main results can be summarized as follows:EG And: The primary minimum in the U light curve (LC) occurred at theend of 2002. A 0.2 -- 0.3 mag brightening in U was detected in theautumn of 2003. Z And: At around August 2002 we detected for the firsttime a minimum, which is due to eclipse of the active object by the redgiant. Measurements from 2003.3 are close to those of a quiescent phase.BF Cyg: In February 2003 a short-term flare developed in the LC. Adifference in the depth of recent minima was detected. CH Cyg: This starwas in a quiescent phase at a rather bright state. A shallow minimumoccurred at JD 2 452 730, close to the position of the inferiorconjunction of the giant in the inner binary of the triple-star model ofCH Cyg. CI Cyg: Our observations cover the descending branch of a broadminimum. TX CVn: At/around the beginning of 2003 the star entered abright stage containing a minimum at JD 2 452 660. AG Dra: Newobservations revealed two eruptions, which peaked in October 2002 and2003 at 9.3 in U. AR Pav: Our new visual estimates showed atransient disappearance of a wave-like modulation in the star'sbrightness between the minima at epochs E = 66 and E = 68 and itsreappearance. AG Peg: Our measurements from the end of 2001 showedrather complex profile of the LC. RW Hya: Observations follow behaviourof the wave-like variability of quiet symbiotics. AX Per: In May 2003 a0.5 mag flare was detected following a rapid decrease of the light to aminimum. QW Sge: CCD observations in B, V, RC, ICbands cover a period from 1994.5 to 2003.5. An increase in the star'sbrightness by about 1 mag was observed in all passbands in 1997. Lesspronounced brightening was detected in 1999/2000. V934 Her: Ourobservations did not show any larger variation in the optical as areaction to its X-ray activity.
| Photometric Investigation of the Nebula in the AG Peg System
Twenty one photoelectric UBV estimates of the symbiotic system AG Peghave been obtained. The continuum flux at a wavelength lambda 3650 A,(the U band) is supposed to be radiated mostly by the circumbinarynebula. Two estimates of this flux, taken in different photometricmaxima are compared. A conclusion that its decrease is probably due to adecrease of the Lyman luminosity of the hot secondary as well as themechanical energy of the two stellar winds in this system has been made.The contribution of the wind of the hot component in the U flux of thewhole system was obtained to be negligible.
| Classification of Population II Stars in the Vilnius Photometric System. II. Results
The results of photometric classification of 848 true and suspectedPopulation II stars, some of which were found to belong to Population I,are presented. The stars were classified using a new calibrationdescribed in Paper I (Bartkevicius & Lazauskaite 1996). We combinethese results with our results from Paper I and discuss in greaterdetail the following groups of stars: UU Herculis-type stars and otherhigh-galactic-latitude supergiants, field red horizontal-branch stars,metal-deficient visual binaries, metal-deficient subgiants, stars fromthe Catalogue of Metal-deficient F--M Stars Classified Photometrically(MDPH; Bartkevicius 1993) and stars from one of the HIPPARCOS programs(Bartkevicius 1994a). It is confirmed that high galactic latitudesupergiants from the Bartaya (1979) catalog are giants or even dwarfs.Some stars, identified by Rose (1985) and Tautvaisiene (1996a) as fieldRHB stars, appear to be ordinary giants according to our classification.Some of the visual binaries studied can be considered as physical pairs.Quite a large fraction of stars from the MDPH catalog are found to havesolar metallicity. A number of new possible UU Herculis-type stars, RHBstars and metal-deficient subgiants are identified.
| The photometric observations of the symbiotic variables Z And, AG Peg and V443 HER in the eighties.
Not Available
| Radial-velocity measurements. III - Ground observations accompanying the HIPPARCOS satellite observation program: Measurements of the radial velocities of 391 stars in 12 fields
The radial velocities of 391 stars, obtained with the Fehrenbachobjective prism associated to the Schmidt telescope of the Observatoirede Haute-Provence are presented. These stars belong to fields speciallychosen for containing several Hipparcos input catalog star members. Eachfield is presented independently. The list includes HD and BDidentifiers when available, 1950 coordinates, spectral type, and B and Vmagnitudes as they appear in the CSI catalog, the radial velocity, theprobable error, the number of independent measurements and commentariessuch as known radial velocity and their origin.
| Photoelectric Photometry of 241 Stars in the Vilnius System
Not Available
| The Period of AG Pegasi - Having Another Go
The period of the symbiotic binary star AG Peg has been determined fromphotoelectric data, including previously unpublished data from the1970s, as well as new observations. Altogether, 89 V magnitudes areavailable for discussion. These are corrected for a discrepancy in themagnitude of a comparison star used by various workers, and for asecular decline in the system's visual brightness of 0.021 mag/yr. Fivedifferent methods of period determination yield consistent results witha mean of 816.5 plus or minus 0.9 days, leading to an ephemeris fortimes of maximum visual light of (JD)max = 2442710.1 + 816.5E. A lightcurve based on normal points formed from the 89 individual observationsis shown.
| UBV Observations of Symbiotic Stars in July and October 1982
Not Available
| Photoelektrische und photographische Beobachtungen des symbiotischen Sternes AG Pegasi.
Not Available
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Группы:
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Наблюдательные данные и астрометрия
| Созвездие: | Пегас |
| Прямое восхождение: | 21h52m25.18s |
| Склонение: | +12°32'49.0" |
| Видимая звёздная величина: | 8.187 |
| Собственное движение RA: | -10.4 |
| Собственное движение Dec: | 18.6 |
| B-T magnitude: | 9.478 |
| V-T magnitude: | 8.294 |
Каталоги и обозначения:
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