Nova V1974 Cyg - Results of the 1997 Campaign

• Autorzy: Olech A.
• Języki publikacji: EN

Abstrakty

EN

This report analyzes the I-band CCD photometry of Nova V1974 Cyg from the 1997 observational season. The analysis shows that both short-term modulations with periods of 0.0813 and 0.085 days are still present in the light curve of the star. We confirmed the stability of the shorter period which is interpreted as the orbital period of the binary system. Its value, determined using the O-C residuals, is P_orb=0.08125873(23) days=117.0126(3) min. The longer period, which appeared in the light curve in 1994, was decreasing until the beginning of 1995 but then started to increase quite rapidly. In October 1996 the value of the period was 122.67±0.02 min. Until the next observing run the period significantly decreased. Its value, as determined from our observations performed in July 1997, was 121.87±0.12 min. This means that the rate of change of the period in 1996-1997 was as high as P≈10-6. Such a rapid change of the period requires a large amount of rotational kinetic energy, if we assume that a 122-min periodicity is the rotation period of a white dwarf. Thus the more probable explanation is the hypothesis that the longer period including a superhump period is caused by the precession of an accretion disc surrounding a white dwarf primary.

Słowa kluczowe

EN

stars: individual: V1974 Cyg; binaries: close; novae; cataclysmic variables

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2002
• Tom: Vol. 52, No. 3
• Strony: 273--291
• Opis fizyczny: Bibliogr. 45 poz., tab., wykr., zdj.

Twórcy

autor

Olech A.

• Nicolaus Copernicus Astronomical Center, Polish Academy of Science, ul. Bartycka 18, 00-716 Warszawa, Poland

Bibliografia

• Alard, C., and Lupton, R.H. 1998, Astrophys. J., 503, 325.
• Alard, C. 1999, Astron. Astrophys., 343, 10.
• Alard, C. 2000, Astron. Astrophys. Suppl. Ser., 144, 363.
• Buat-Menart, V., and Hameury, J.-M. 2002, Astron. Astrophys., 386, 891.
• DeYoung, J.A., and Schmidt, R.E. 1993, IAU Circ., No. 5880.
• DeYoung, J.A., and Schmidt, R.E. 1994, Astrophys. J. Letters, 431, L47.
• Kałużny, J., Olech, A., and Stanek, K.Z. 2001, Astron. J., 121, 1533.
• Kato, T., and Kunjaya, C. 1995, PASJ, 47, 163.
• Kato, T., Nogami, D., Baba, H., Matsumoto, K., Arimoto, J., Tanabe, K., and Ishikawa, K. 1996, PASJ, 48, L21.
• Kopacki, G. 2001, Astron. Astrophys., 369, 862.
• Kornet, K., and Różyczka, M. 2000, Acta Astron., 50, 163.
• Krautter, J., Klare, G., Wolf, B., Wargau, W., Dreschel, H., Rahe, J., and Vogt, N. 1996, Astrophys. J., 456, 788.
• Kruszewski, A., and Semeniuk, I. 1993, Acta Astron., 43, 127.
• Leibowitz, E.M., Mendelson, H., Gefen., G., and Retter, A. 1995, Baltic Astronomy, 4, 453.
• Mochejska, B.J., Kaluzny, J., Stanek, K.Z., Sasselov, D.D., and Szentgyorgyi, A.H. 2001, Astron. J., 121, 2032.
• Mochejska, B.J., Stanek, K.Z., Sasselov, D.D., and Szentgyorgyi, A.H. 2002, Astron. J., 123, 3460.
• Nogami, D., Kato, T., Baba, H., and Masuda, S. 1998a, PASJ, 50, L1.
• Nogami, D., Kato, T., and Masuda, S. 1998b, PASJ, 50, 411.
• Olech, A. 1997, Acta Astron., 47, 281.
• Olech, A., Semeniuk, I., Kwast, T., Pych, W., DeYoung, J.A., Schmidt, R.E., and Należyty, M. 1996, Acta Astron., 46, 311.
• Olech, A., Woźniak, P., Alard, C., Kałużny, J., and Thompson, I.B. 1999, MNRAS, 310, 759.
• Osaki, Y. 1996, P.A.S.P., 108, 39.
• Osborne, J.P., and Mukai, K. 1989, MNRAS, 238, 1233.
• Olson, E.P. 1977, Astrophys. J., 215, 166.
• Patterson, J., and Warner, B. 1998, P.A.S.P., 110, 1026.
• Patterson, J., Thorstensen, J.R., Fried, R., Skillman, D.R., Cook, L.M., and Jensen, L. 2001, P.A.S.P., 113, 72.
• Patterson, J. et al. 2002, P.A.S.P., 114, 65.
• Pych, W., and Olech, A. 1995, Acta Astron., 45, 385.
• Retter, A., Leibowitz, E.M., and Ofek, E.O. 1997, MNRAS, 286, 745.
• Retter, A., and Leibowitz, E.M. 1998, MNRAS, 296, L37.
• Schwarzenberg-Czerny, A. 1989, MNRAS, 241, 153.
• Semeniuk, I., DeYoung, J.A., Pych, W., Olech, A., Ruszkowski, M., and Schmidt, R.A. 1995, Acta Astron., 45, 365.
• Semeniuk, I., Pych, W., Olech, A., and Ruszkowski, M. 1994, Acta Astron., 44, 277.
• Skillman, D.R., and Patterson, J. 1993, Astrophys. J., 417, 298.
• Skillman, D.R., Harvey, D., Patterson, J., and Vanmunster, T. 1997, P.A.S.P., 109, 114.
• Skillman, D.R., Patterson, J., Kemp, J., Harvey, D., Fried, R.E., Retter, A., Lipkin, Y., and Vanmunster, T. 1999, P.A.S.P., 111, 1281.
• Skillman, D.R., et al. 2002, P.A.S.P., 114, 630.
• Soszyński, I., Żebruń, K., Woźniak, P.R., Mao, S., Udalski, A., Szymański, M., Kubiak, M., Pietrzyński, G., Szewczyk, O., and Wyrzykowski, Ł. 2001, Astrophys. J., 552, 731.
• Stetson, P.B. 1987, P.A.S.P., 99, 191.
• Taylor, C.J., et al. 1998, P.A.S.P., 110, 1148.
• Thomas, G.R. 1993, BAAS, 25, 909.
• Udalski, A., and Pych W. 1992, Acta Astron., 42, 285.
• Uemura, M., Kato, T., Pavlenko, E., Baklanov, A., and Pietz, J. 2001, PASJ, 53, 539.
• Uemura, M., et al. 2002, PASJ, 54, 285.
• Woźniak, P.R., Udalski, A., Szymański, M., Kubiak, M., Pietrzyński, G., Soszyński, I., and Żebruń, K. 2000, Astrophys. J., 540, 65.