SIMBAD references

We report the first results for the latest outburst of the recurrent nova T Pyx from the FIES echelle spectrograph on the 2.6 m Nordic Optical Telescope (NOT) at La Palma from 3700-7200 A with a resolution

of 67000. The first spectrum, obtained on 2011 Apr. 15.92 UT during the

rise to maximum (V ~9.5) with integration time of 600 sec with a S/N of 30 at 6000 A (continuum), was sufficiently well exposed to display some of the strongest optical diffuse interstellar bands (DIBs). Friedman, S. D. et al. (2011, ApJ, 727, 33) provide calibrations of the neutral and molecular hydrogen column densities and reddening E(B-V) for 5870, 6205, 6283, 6405, 6614, uncertainties in the measurements are ± 3 mA with a systematic (calibration) uncertainty of about 10% for each DIB. Our mean reddening is E(B-V)=0.44±0.18 with all values being greater than 0.2. The two strongest DIBs, 5780 A and 6283 A, agree in mean velocity with the mean radial velocity of the Na I D and Ca II H and K lines measured on

the same spectra, both ions showing components at +26 and +35 km/s. The velocities agree with a spur noted in the H I 21 cm line measurements in the 4th quadrant. The DIB 6204 A appears, instead,

to have a velocity of around +15 km/s. There are no archival STIS or GHRS spectra of sufficiently high velocity resolution along this line of sight with which these can be compared (unlike e.g. V407 Cyg (Shore

et al. 2011, A&A, 527, A98; also obtained with FIES and which which our present spectra were compared for identification). The higher positive velocity Na I D component is marginally saturated, with FWHM of 7 km/s while the weaker, lower velocity component is broader, 14 km/s. A second spectrum, also a 600 sec expoure, obtained on Apr. 23.92 UT confirms the presence of the features and their equivalent widths. This reddening value is higher than both the Schlegel,

Finkbeiner, & Davis (1998, ApJ, 500, 525) value in this direction and the value, ∼0.25, based on the colors of the system and the previous outbursts and may affect planning for optical and ultraviolet satellite observations and for interpreting XR data.