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1.
The published photometric and spectroscopic data of the symbiotic binary V 1329 Cyg are interpreted. It is shown, that V 1329 Cyg is an eclipsing binary with an elliptical orbit orbit (e=0.28). The cooler component fills up the Roche-lobe at periastron. A model of moving gaseous structures in the system is proposed and their influence on the radial velocity curve is shown. The following characteristics of the system are derived: the cooler component is an M6 giant with mass 7.9M
, radius 339R
and luminosityM
bol=–5.42, the hot component is a white dwarf surrounded by an accretion disk. The mean distance between the components is 842R
and in periastron it decreases to 605R
. 相似文献
2.
On the coronograph spectrophotographic records taken on 31.372 UT, August 1979, some faint emission features were found which can be ascribed to Siii and Niii. These emissions were obviously a transient phenomena which were detected only 10 hr after the supposed fall of Comet 1979 XI in the Sun's photosphere. It cannot be excluded that the appearance of Si and Ni lines was triggered by the evaporation of dust particles with a high abundance of heavier elements in the solar corona. This assumption is also supported by intensity distribution of the Fex coronal line around the Sun's limb. The maximum coincide with the position angle of the projected path of the comet. 相似文献
3.
Drahomír Chochol Theodor Pribulla Nataly A. Katysheva Sergei Yu. Shugarov Igor M. Volkov 《Astrophysics and Space Science》2005,296(1-4):135-139
UBV RI photometry and 4600–9000 Å spectroscopy of nova V475 Sct taken in the first 3 month after discovery is presented. The object can be classified as a Fe II type slow nova with t 2,V = 48 days, t 3,V = 53 days. The absolute magnitude of the nova at maximum, its colour excess and distance were determined. The observed 13.4 day periodicity of flares can be explained by the mass transfer bursts from the red to the white dwarf, probably caused by the periastron passage of a third body. Two sets of absorptions are seen in the P Cyg-type Hα line profile. They arise in the expanding shell of the nova. 相似文献
4.
Theodor Pribulla Martin Vaňko DrahomÍr Chochol Štefan Parimucha Daniel Baluďanský 《Astrophysics and Space Science》2005,296(1-4):281-284
New photoelectric and CCD observations of the eclipsing contact binary systems V344 Lac and V1191 Cyg are presented and analyzed.
All available times of minimum light were used to study period changes of the systems and determine up-to-date ephemerides.
The orbital period of V1191 Cyg is found to be increasing at a very fast rate. The photometric elements were determined using
the new light curve, radial-velocity curve and broadening function fitting code ROCHE. 相似文献
5.
D. Chochol T. Pribulla M. Vaňko P. Mayer M. Wolf P. G. Niarchos K. D. Gazeas V. N. Manimanis L. Brát M. Zejda 《Astrophysics and Space Science》2006,304(1-4):93-96
Orbital period changes of the eclipsing binaries GO Cyg and GW Cep are explained by the light-time effect for the first time. New minima of the eclipsing binary AR Aur improve the predicted light-time orbit. The light-time orbit with the quadratic ephemeris of the binary matches the new observations of V505 Sgr better than the linear one. As the light-time effect fits in corresponding O − C diagrams of all four systems have been reaching extreme values, the observations of minima times in forthcoming years are highly desirable. 相似文献
6.
Astronomy Reports - The first high-accuracy CCD UBV RI (RI)C light curves of the recently discovered eclipsing binary V2647 Cyg = GSC 3612 1565 ( ) have been obtained. The photometric light curves... 相似文献
7.
Chochol Teodorani Strafella Errico & Vittone 《Monthly notices of the Royal Astronomical Society》1998,293(4):L73-L77
High-resolution, time-resolved spectroscopic observations of Z CMa carried out on 1997 January 14–17 are presented. Large night-to-night and hour-to-hour variations in Hα, Hβ and Na i D P Cygni absorptions, as well as an Hβ emission peak, were observed. Variations in the red wings of the hydrogen emission lines were also detected. The high-velocity wide-emission component on the blue side of Hα appeared on January 17. The observations are discussed in the framework of current wind models. 相似文献
8.
Sergei Yu. Shugarov Vitalij P. Goranskij Nataly A. Katysheva Anatolij V. Kusakin Nataly V. Metlova Igor M. Volkov DrahomÍr Chochol Theodor Pribulla Eugenia A. Karitskaja Alon Retter Ohad Shemmer Yiftah Lipkin 《Astrophysics and Space Science》2005,296(1-4):431-434
UBVRI photoelectric and CCD photometry of the slow nova V723 Cas obtained in the years 1995–2003 is presented. The evolution
of light curves in 1-year intervals, folded with the orbital period 0.69326 days, shows an increase of the amplitude of the
wave-like variations from 0.07 to 1.3 mag during the years 1997–2003. The fact that the shape and amplitude of the orbital
light curves does not depend on wavelength is most probably related to the geometry of eclipses combined with the distribution
of circumstellar matter in the system. 相似文献
9.
A. Skopal M. Va&#x;ko T. Pribulla D. Chochol E. Semkov M. Wolf A. Jones 《Astronomische Nachrichten》2007,328(9):909-916
We present new photometric observations of 15 symbiotic stars covering their last orbital cycle(s) from 2003.9 to 2007.2. We obtained our data by both classical photoelectric and CCD photometry. Main results are: EG And brightened by ∼0.3 mag in U from 2003. A ∼0.5 mag deep primary minimum developed in the U light curve (LC) at the end of 2006. ZAnd continues its recent activity that began during the 2000 autumn. A new small outburst started in summer of 2004 with a peak U magnitude of ∼ 9.2. During the spring of 2006 the star entered a massive outburst. It reached its historical maximum at U ∼ 8.0 in 2006 July. AEAra erupted in 2006 February with Δmvis ∼ 1.2 mag. BF Cyg entered a new active stage in 2006 August. A brightness maximum (U ∼ 9.4) was measured during 2006 September. CH Cyg persists in a quiescent phase. During 2006 June–December a ∼ 2 mag decline in all colours was measured. CI Cyg started a new active phase during 2006 May–June. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
10.
Pavel Mayer Marek Wolf P. G. Niarchos K. D. Gazeas V. N. Manimanis Drahomír Chochol 《Astrophysics and Space Science》2006,304(1-4):39-41
New precise times of minimum light for several early-type eclipsing binaries were obtained at three observatories. The changes of period of the following measured binaries are discussed: V1182 Aql, LY Aur, SZ Cam, FZ CMa, QZ Car, LZ Cen, V606 Cen, AH Cep and TU~Mus. 相似文献