SIMBAD references

We have continued out high resolution optical spectroscopy of the latest outburst of T Pyx with the FIES fiber-fed echelle (R ∼ 67000) as first reported in ATel 3306. Here we describe the changes in the optical resonance and Fe II lines. The first observation, obtained on 2011 Apr. 15.92 UT, shows a pre-maximum spectrum (e.g. McLaughlin, D. B. 1964, Ann.Ap., 27, 450, now identified as the so-called fireball stage) showing only Balmer series and He I/II with P Cyg components extending to -3000 km/s, and a complex blend at C III/ N II 4640 A. The second spectrum, Apr. 23.9 UT, shows no He II and only weak He I, and the 4640 A feature had vanished. Instead, weak emission and possible P Cyg absorption was detected at Na I 5889,5895 and on Ca II 3933,3964 A with P Cyg profiles on Fe II RMT 42

but not other lines arising from the same level. The P Cyg absorption became more evident on the next spectrum, May 6.9 UT, for all of these

transitions showing detached components at progressively higher velocities. The Na I D line illustrates this evolution (Na I P Cyg profiles and their changes have been noted for only a few other novae, notably V705 Cas 1993): May 6.88 UT, -1900, -1160, -660 (weak); May 15.90 UT, -2000, -1350, -820;

May 21.87 UT: -2200 with numerous narrower components. The highest velocity feature is seen for only Na I D1 on all spectra with approximately constant FWHM ∼ 350±50 km/s and constant profile despite increasing velocity. The last spectrum appears to show a very broad emission component at +2000 to +3000 km/s. The velocity shifts and profiles are consistent with a linear velocity law for some form of continuous flow that is being occasionally loaded with mass by a source

that is pulsing, perhaps coincident with the events noted on the light curve in ATel 3373. If so, the forcing cannot be radiative, there is no evidence a terminal velocity, and the velocity gradient appears to be very steep near the temporary ``photosphere'' (see Shore et al. 1994, AJ, 108, 671 for the symbiotic system MWC 560). The individual narrow

components appear to be emerging as the broad absorption features become

progressively more transparent but were already present. Similar changes

to Na I D are seen on the Fe II RMT 42 profiles and Ca II.