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We present the first Fourier Transform Spectrograph near-IR spectrum (0.95-2.5 mu m) of eta Car observed at CFHT in January 1987 with a resolution of 40-100 km s(-1). We have identified lines of H I (Paschen, Brackett series), He I, Fe II, [Fe III, [N I] with complex structures. At the time of these observations eta Car was in a low excitation phase characterized by a general weakening of the hydrogen lines, and with the He I lambda 1082.9 nm line much weaker than in 1990-91.

Following a previous study by Altamore et al. (1982, Paper I) of the ultraviolet spectrum of KQ Pup, and the spectral Atlas of this star by Altamore et al. (1991, Paper II), we analyze coude and CAT CES optical spectra of the object observed during 1969-1984, and compare with IUE data obtained in 1979. Besides the M-star photospheric absorptions, the optical spectrum shows sharp emissions of [S II], [Cu II], [Fe II], Fe II, and [Ni II]. They probably arise in an intermediate region of the M-star wind ionized by the hot star radiation, where also the P Cygni UV lines of ionized metals are formed. The region is more extended and closer to the M-star near periastron passage. The earlier Balmer lines present a double peaked emission with a sharp central absorption which in 1979 and 1983 appears double suggesting the presence of streams or clouds of matter in the system environment. The redshifted emission component disappears in the higher series members, giving rise to an inverse P Cygni profile. Some Balmer lines display very broad absorption components which are identified as the density broadened hot star photospheric lines. He I is probably present with a rotationally broadened absorption at 3819 angstrom largely hidden by the rich M-star spectrum. In the UV the resonance lines and the excited lines of the doubly ionized metals are broad and redshifted by about +37 km s-1 with respect to the M-star radial velocity, implying line formation in opaque and turbulent matter flowing near and towards the surface of the hot star. From the blue-IR colour indices and the 2200 angstrom interstellar band we derive for KQ Pup a colour excess of E(B-V) = 0.14 +/- 0.03. The ultraviolet to infrared energy distribution appears bimodal with the hot component dominating below about 3600 angstrom and the M star above 4000 angstrom. We have fitted the dereddened energy distribution with a combination of a 30 000 K black body and of a M-supergiant spectrum (alpha-Ori), and derived for KQ Pup a distance at 1400 +/- 200 pc. At this distance the hot component results a slightly underluminous BOV star with a radius of 4.35R.. The mass ratio of the components of the binary system seems to be close to unity. We propose for KQ Pup a binary model with a highly mass losing cool supergiant primary and an unevolved early-type secondary. The optical and UV emission lines are formed in the regions of the cool star wind which are ionized by the hot star radiation. A shock is probably produced near the hot star by the interaction of the cool star wind with the hot star wind. Instabilities probably occur near the shock which produce cool clouds from the M-star wind, which may penetrate the hot star wind and be accreted.

The authors investigate the symbiotic character of BI Cru by means of a 59 Å/mm spectrogram of the 5700 - 6900 Å region obtained at the 1.5 m ESO telescope on 18 February 1983.

The nature of BX Mon, a peculiar star characterized by a composite spectrum and very long period photometric variability, has been investigated. The star has been included in an extensive program of ESO observations of emission line stars. New results are discussed based on coordinated optical (IDS) and infrared observations made in February 1983, on high resolution H alpha spectrophotometry made with CAT-CES in February 1984, and on infrared photometry of March 1985. The 1983 spectrum is composite with prominent hydrogen and weak He I emission lines, and a cool continuum with strong TiO absorptions. The red-infrared energy distribution, corrected for an interstellar extinction of (B-V) = 0.2, suggests for the cool component an M5 III spectral type in agreement with the strength of the TiO red bands. A distance of 2800 pc is estimated for the system. An excess with respect to the M continuum is present shortward of 600 nm and is attributed to a hotter component and to nebular emission. The 1984 H alpha profile is complex, with two-component emission, and a broad red red-shifted shell absorption probably produced in a wind from the cool giant with a velocity of 59 km/s. The observations indicate that presently the cool M-type component of BX Mon is rather stable - certainly not a Mira variable in agreement with its being an S-type symbiotic. The reported photometric variability could be attributed to the hot component.

L. Piro, Istituto TESRE, Bologna; A. Cassatella, IUE Observatory, Villafranca; L. Spinoglio and R. Viotti, Istituto Astrofisica Spaziale, Frascati; and A. Altamore, Istituto Astronomico, Rome, telex: "We detected x-ray emission from the high-velocity symbiotic star AG Dra at minimum phase. The star was observed with EXOSAT on June 5. Using a bremsstrahlung model with log nH = 20.2, we find kT = 24 eV and a 0.2-1.0-keV flux of 3.4 x 10**-16 J m**-2 s**-1. Coordinated IUE observations on June 9 showed an ultraviolet spectrum typical of minimum phase. There was no ultraviolet contamination of EXOSAT fluxes. The fine-error-sensor magnitude was 9.8. Infrared photometry on May 2 and 23 gave: J = 7.12, H = 6.36, K = 6.27, confirming that the K star is substantially stable."

Objective prism plates of the optical" "counter.part of the transient X-ray source A0535+" "26 obtained during 1977 show strong H""' in emis­ sion and marked Balmer excess. Many other emis­ sion lines are probably present in the red-infra­ red.No large spectral time variation was found

Z ANDROMEDAE G. Baratta, Rome Observatory; A. Altamore, Rome University; A. Cassatella, European Space Agency, Madrid; and A. Giangrande, O. Ricciardi and R. Viotti, Laboratorio di Astrofisica Spaziale, Frascati, report that new ultraviolet spectra of Z And obtained with the International Ultraviolet Explorer on Feb. 17 showed no significant change in the emission lines. The minimum electron density in the emitting region was 10**9 cm**-3. The optical spectrum, obtained at Campo Imperatore, and the luminosity are still those of the quiescent phase.

The high resolution spectrum of the VV Cep star KQ Pup observed with the IUE satellite during 1979 and 1980 is summarized. More than 600 lines have been identified between 1190 and 3228 A. Two main line systems are present, a broad absorption line system, which includes high ionization lines from N V, C IV, Si IV and Al III, and narrow P Cygni lines of neutral and singly ionized elements, mostly of Fe II. The Mg II resonance doublet is very prominent in emission with a sharp central absorption. The intensity of the absorption and emission components of the Fe II lines is different according to the excitation potential, transition strength and wavelength. Fe II emission lines with E.P. up to 13 eV are present. Several Fe II lines, were identified using the new Kurucz's computations.

Several objective prism spectra of objects known to have large ultraviolet or X-ray fluxes are discussed. A marked Balmer excess and H alpha emission are found in X Per(= 3U 0352 + 30) and in the similar Be star HD 200775. No Balmer discontinuity is detectable in HD 226868 (Cyg X-1) during the low X-ray states, in HZ 43 (MX 1313 + 29), and in the hot subluminous star BD + 37 deg 1977. Comparison with the far ultraviolet spectrum of this star (Carnochan et al., 1975) leads to the conclusion that the star is slightly reddened (EB-V = 0.15 plus or minus 0.05) with an optical-ultraviolet energy distribution close to a 100,000 K black-body.

The Herbig Be star HD 200775, associated with the extended reflection nebulae NGC 7023, has been observed in the ultraviolet with the IUE satellite, in the optical with the 90-cm Schmidt telescope of Campo Imperatore Observatory, and in the infrared with the 2.3 m telescope of Wyoming University in a coordinated campaign made during August 1978. The ultraviolet low-dispersion spectrum shows several strong absorption resonance lines (C II, C IV, Si II, Si IV, Al III . . .) probably formed in an expanding envelope. From the IR observations up to 12.6 microns, a value of the mass loss rate expansion velocity ratio of 2.3 x 10 to the -9th solar masses/year per km/sec is derived. The infrared energy distribution shows also the presence of a dust shell at a mean distance of about 3 x 10 to the 14th cm from the central star. A value of the color excess of 0.25 + or - 0.05 is derived from the 2200-A interstellar band and from the gradient of the UV continuum.

The observation of the X-ray spectrum of peculiar emission line stars, whose atmospheric envelopes are characterized by extreme physical conditions, represents an important tool to investigate the processes of formation of high temperature plasmas. The authors discuss the case of the superluminous object η Car showing both high and low temperature regions and an asymmetric wind. They present new EXOSAT observations of symbiotic stars. AG Draconis observed at a minimum phase shows a low temperature X-ray spectrum. A weak flux from the Mira variable R Aqr observed near maximum has been also detected.

Summary. The use of a nationacomputer network for the analysis and interpretation of the stellar spectra is outlined, with parti­ cular regard to the creation of data bases and sharing of up-to­ dated sofwares among the poles of the network. We describe the systems that have been developed at the IAR-CNR, which include the Kurucz' model atmosphere package and reduction programs for the IUE spectra. We also discuss the future developments, like the computation of synthetic spectra and the creation of extensive and homogeneous collctions of stellar spectra.

A coordinated campaign of simultaneous X-ray and ground-based photometric and spectroscopic observations of X Persei = 3U 0352 + 30 was organized from February 14 to March 2, 1977. The optical observations show little photometric activity, a less marked Balmer excess than in 1971-72, weaker emission than in 1970, and a nearly normal intrinsic color. The H-alpha emission is double with R about equal to V. No clear correlation with the X-ray emission was found, except for the lower intensity probably related to a lower 'activity' of the optical source. A best-fit heliocentric X-ray period of 835.05 + or - 0.15 is found.

A. Altamore, Istituto Osservatorio Astronomico Universita' di Roma; R. Viotti, Laboratorio di Astrofisica Spaziale, Frascati; and G. B. Baratta, Osservatorio Astronomico di Roma, telex: "Nova Cyg 1978 was observed on Sept. 12.0 and 14.0 UT with the Schmidt telescope of the Rome Astronomical Observatory at Campo Imperatore. Several objective-prism spectrograms were obtained on IIa-O and I-N emulsions. The Sept. 12 spectrograms are overexposed, and only a few features are detectable: Balmer H10 and H11 in emission, Ca II 3933 A, 3968 A and a strong structure at 3920 A (probably Mg I 3838 A) in absorption. The Sept. 14 spectrum shows broad Balmer emission lines from H-alpha to H11. Fe II blends (4450-4620, 4210-4310, 4140-4190 A) are strong in emission. In absorption there are present: Ca II 3933 A, 3968 A with a violet shift of about 15 A; Ca I 4227 A and the probable Mg I 3838 A. The ultraviolet continuum is strong."

During its first 2 years of operation, the gamma-ray AGILE satellite accumulated an extensive dataset for the Galactic plane. The data have been monitored for transient sources and several gamma-ray sources were detected. Their variability and possible association were studied. In this talk we will focus on the results of extensive observations of the Carina Region during the time period 2007 July - 2009 January, for a total livetime of ~130 days. The region is extremely complex, hosting massive star formation, with the remarkable colliding wind binary Eta Carinae, massive star clusters and HII regions (e.g. NGC 3324, RCW49, Westerlund II) and a giant molecular cloud extending over 150 pc (between l=284.7 and l=289). The Carina Nebula itself is the largest and IR highest surface brightness nebula of the Southern emisphere. We monitored several gamma ray sources in the Carina Region. In particular we detect a gamma ray source (1AGL J1043-5931) consistent with the position of Eta Carinae and report a remarkable 2-days gamma-ray flaring episode from this source on 2008 Oct 11-13. If 1AGL J1043-5931 is associated with the Eta Car system, our data provides the long sought first detection above 100 MeV of a colliding wind binary., 5 pages, 5 figures, proceedings of RICAP 2009

Since 1980 the high velocity symbiotic system AG Dra has undergone three phases of activity (or “outbursts”) which were extensively observed in optical, ultraviolet and X-ray bands. We describe the historical light curve of the star, and summarize 17 years of UV monitoring with the IUE satellite.

From the analysis of the galactic counterparts of the HS variables, η Car, AG Car and P Cyg we conclude that their atmospheres are near critical physical conditions so that small changes of the mass outflow could produce a large variation of the atmospheric structure and nova-like explosions at nearly constant Mbol.

An atlas of the high-resolution UV spectrum of Eta Car from 1200 to 1974 A and from 2200 to 3230 A is presented, based on IUE observations made between 1978 and 1980. The fluxes and equivalent widths of the emission and absorption features, and the stellar continuum in line-free regions are presented. The profiles displayed by the most intense emission suggest line formation in an asymmetric envelope. Many of the observed features may be explained if Eta Car is an intermediate, possible binary, F-type hypergiant in a short living stage, which holds a massive wind heated by dissipation of mechanical energy. 61 refs.

High- and low-resolution UV spectrograms of the symbiotic star Z Andromedae were made during 1978-79 with the International Ultraviolet Explorer (IUE) and coordinated with ground-based observations. The spectrograms extend from 1200 to 3341 A and show a rich emission line spectrum with a wide range of ionization energy, from O I, Mg I and II and Fe II to He II, N V, O V, and Mg V. From the analysis of the emission lines, an electron density of 2 x 10 to the 10th/cu cm is derived, along with an emitting volume of 1 x 10 to the 37th/cu cm and a maximum line-of-sight thickness of 6 x 10 to the 10th cm. It is argued that the high-ionization emission lines are formed in a region which is not nebular, but in a solar-type transition zone around the cool star.

High quality IUE spectra of AG Dra gathered during 1979-81 were examined in concert with data taken at VILSPA. Visual bursts were detected in 1980 and 1983 and were associated with order of magnitude changes in the UV continuum and emission lines. Variability was persistent in the UV and He II lines after the bursts while the C IV line displayed small variations and the N V line was nearly constant. A binary system is indicated, composed of a nonvariable K-giant and a dwarf companion which accretes matter from a cooled stellar wind. The variability would arise from an extended region near the cool star heated by UV or X ray radiation from the giant. A wider range of spectral data are required to flesh out the physical processes of the accretion region, which may be a disk.