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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.
| Hipparcos red stars in the HpV_T2 and V I_C systems
For Hipparcos M, S, and C spectral type stars, we provide calibratedinstantaneous (epoch) Cousins V - I color indices using newly derivedHpV_T2 photometry. Three new sets of ground-based Cousins V I data havebeen obtained for more than 170 carbon and red M giants. These datasetsin combination with the published sources of V I photometry served toobtain the calibration curves linking Hipparcos/Tycho Hp-V_T2 with theCousins V - I index. In total, 321 carbon stars and 4464 M- and S-typestars have new V - I indices. The standard error of the mean V - I isabout 0.1 mag or better down to Hp~9 although it deteriorates rapidly atfainter magnitudes. These V - I indices can be used to verify thepublished Hipparcos V - I color indices. Thus, we have identified ahandful of new cases where, instead of the real target, a random fieldstar has been observed. A considerable fraction of the DMSA/C and DMSA/Vsolutions for red stars appear not to be warranted. Most likely suchspurious solutions may originate from usage of a heavily biased color inthe astrometric processing.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997).}\fnmsep\thanks{Table 7 is onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/397/997
| Photometry of symbiotic stars. X. EG And, Z And, BF Cyg, CH Cyg, V1329 Cyg, AG Dra, RW Hya, AX Per and IV Vir
We present new photometric observations of EG And, Z And, BF Cyg, CHCyg, V1329 Cyg, AG Dra, RW Hya, AX Per and IV Vir made in the standardJohnson UBVR system. The current issue summarizes observations of theseobjects to 2001 December. The main results can be summarized as follows:EG And: A periodic double-wave variation in all bands as a function ofthe orbital phase was confirmed. A maximum of the light changes wasobserved in U (Delta U ~ 0.5 mag). Z And: Our observations cover anactive phase, which peaked around 8.4 in U at the beginning of 2000December. Consequently, a gradual decrease in the star's brightness hasbeen observed. BF Cyg: A periodic wave-like variation in the opticalcontinuum reflects a quiescent phase of this star. A complex light curve(LC) profile was observed. CH Cyg: The recent episode of activity endedin Spring 2000. We determined the position of an eclipse in the outerbinary at JD 2451426 +/- 3. Recent observations indicate a slow increasein the star's brightness. V1329 Cyg: Observations were made around amaximum at 2001.2. AG Dra: Our measurements from the Autumn of 2001revealed a new eruption, which peaked at ~JD 2452217. RW Hya: The lightminimum in our mean visual LC precedes the time of the spectroscopicconjunction of the giant in the binary. AX Per: A periodic wave-likevariation was observed. Our recent observations revealed a secondaryminimum at the orbital phase 0.5, seen best in the V and B bands. IVVir: The LC displays a double-wave throughout the orbital cycle.
| GPM - compiled catalogue of absolute proper motions of stars in selected areas of sky with galaxies.
Not Available
| GPM1 - a catalog of absolute proper motions of stars with respect to galaxies
The description of the first version of the General Compiled Catalogueof Absolute Proper Motions (GPM1) for a sample of HIPPARCOS stars,derived with respect to galaxies within the plan called Catalogue ofFaint Stars (KSZ, Deutch 1952), is presented. The principal aim of theGPM1 construction was to provide absolute proper motions of stars todetermine the rotation of the HIPPARCOS system. The GPM1 cataloguecontains 977 HIPPARCOS Input Catalogue stars with V magnitudes $5^m -11^m in 180 fields north of -25 degrees of declination. The accuracy ofthe proper motions is 8 mas/yr (milliarcseconds per year). Comparison ofproper motions of GPM1 with those of the PPM and ACRS was performed andanalyzed with respect to systematic errors caused by spurious rotationof the FK5 system. The standard errors show that the rotation may bedetermined with an accuracy better than 1 mas/yr. Catalog is onlyavailable in electronic form at the CDS via anonymous ftpcdsarc.u-strasbg.fr or ftp 130.79.128.5.
| Is the symbiotic binary EG And an eclipsing system?
We present all available UBV photometry of the symbiotic binary EG Andobtained during the last 10-years. The light curves display a doublewave through one orbital cycle. It is shown that this behaviour cannotbe explained by eclipses of the two detached sources of the continuumradiation. The present models of EG And are not able to simulatesatisfactorily variation in both the far ultraviolet and the opticalcontinuum.
| Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
| A giant's envelope in the eclipsing symbiotic EG Andromedae
The secondary minimum close to the superior conjunction of the giantstar, recently observed in two symbiotic binaries (Skopal & Komarek1990; Skopal et al. 1991; Hric et al. 1991) is confirmed andreinterpreted as an occultation of the giant due to an extended brightregion near the hot companion. At the primary minimum the radiation bythe same region and by the white dwarf is scattered and markedlyweakened by the extended atmosphere of the late type giant. New orbitalelements and a radial velocity curve of the HeI emission in EG And implya mass ratio lower than 1. They constrain the giant's radius to belarger than 159 +/- solar mass, for the lowest value of the massadmitted for white dwarfs. The size of the giant atmosphere, which isbigger than that of the photosphere of a typical giant (80 solar mass),is possibly the result of the formation of a thick envelope with aradius not less than 279 +/- solar mass, in agreement with the estimateby Shore & Aufdenberg (1993), irrespective of the secondary minimuminterpretation.
| Photometric minimum confirmation and eclipse modelling for the symbiotic system EG Andromedae
Photometric observations carried out from October to November 1991 ofthe symbiotic system EG Andromedae are here presented. The secondaryminimum has been repeated with a period of about 480 days, as inferredfrom the orbital elements (P = 482 days, Skopal et al., 1991). The lightcurve shape led us to suggest a model in which two hot spots resultthrough evaporation from a low mass red giant by a compact object.
| Ultraviolet activity in EG Andromedae
It is shown that the symbiotic star EG And is an active variable in theground-based ultraviolet. In five nights of observation spaced over oneyear, the full range at Stromgren u was 0.97 m, as compared to only 0.13m y. The energy distribution in the visual is typical of a cool giant,but a significant component of the radiation at u appears to come fromthe hot active source seen with the IUE.
| An image reconstruction for Capella with the Steward Observatory/AFGL intensified video speckle interferometry system
Since their invention in 1970, speckle interferometric techniques haveevolved from simple optical processing of photographic images tohigh-speed digital processing of quantum-limited video data. Basicspeckle interferometric techniques are discussed, taking into accountthe implementation of two distinct data-recording/data-processing modes.A description of image reconstruction techniques is also provided. Twomethods for image phase retrieval have been implemented, including aphase unwrapping method developed by Cocke (1980) and the phaseaccumulation method of Knox and Thompson (1974). On February 3, 1981,analogue mode speckle interferograms for Capella and the unresolved starGamma Ori were obtained with both the phase-unwrapping and theKnox-Thompson method.
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
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Osservazione e dati astrometrici
| Costellazione: | Andromeda |
| Ascensione retta: | 00h44m16.73s |
| Declinazione: | +40°41'06.6" |
| Magnitudine apparente: | 8.624 |
| Distanza: | 694.444 parsec |
| Moto proprio RA: | 4.9 |
| Moto proprio Dec: | -17.7 |
| B-T magnitude: | 10.608 |
| V-T magnitude: | 8.788 |
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