J. Eisloffel, E. Gunther, F. V. Hessman, R. Mundt, and R. Poetzel, Max-Planck-Institut fur Astronomie, Heidelberg; S. Beckwith, Cornell University; J. Carr, University of Hawaii; and T. Ray, Dublin Institute for Advanced Studies, communicate: "We confirm the optical outburst of SVS 13, the exciting source of Herbig-Haro objects 7-11 (cf. IAUC 5261; R.A. = 3h25m58s.15, Decl. = +31 05'45".2, equinox 1950.0). According to our CCD archives and recently obtained CCD images from the Calar Alto 3.5-m telescope, the outburst of about 3 mag occurred between 1988 Dec. and 1990 Sept. Our CCD frames taken through a narrowband red filter (central wavelength 674 nm) show that the source was still rising by about 0.06 mag/month between 1990 Sept. and 1991 Feb. 9 (our last measurement). A similar outburst amplitude is observed at V, R, and I. On 1991 Jan. 17, we measured B = 22.8, V = 20.2, R = 18.1, and I = 16.0 at the ESO/ MPI 2.2-m telescope. Infrared photometry carried out in early 1991 Jan. at the Palomar 5-m telescope provided the following magnitudes: J = 11.84, H = 9.92, K = 8.05, L' = 5.66, M = 4.28, and N = 1.5. Compared to the measurements of Cohen and Schwartz from 1981 Dec. (Ap.J. 265, 877), the outburst amplitude is 1.8 mag in H, 1.2 mag in K, and 0.35 mag in N. An optical spectrum in the red of SVS 13 obtained on 1990 Nov. 19 at the Calar Alto 3.5-m telescope shows emission lines (H-alpha, Fe II 651.6-nm) typical of a T Tau star or Herbig-Ae star. An infrared spectrum around 2.3 microns obtained on 1990 Dec. 17 at the University of Hawaii 2.2-m telescope shows no change (compared to 1986 Oct.) in the equivalent widths of the CO emission band heads (nu = 2-0 and 3-1). Follow-up observations at optical, infrared, and radio wavelengths are urgently required to monitor the unique outburst of this famous young outflow source."
International Astronomical Union Circular
- Pub Date:
- July 1991