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We present the second part (days 19 to 102) of our high-resolution Echelle atlas of the spectral evolution of RS Oph during the 2021 nova outburst. Some quick conclusions that can be drawn are: (1) the spectra evolution has progressed smoothly, suggesting that both the expansion of the ejecta through the pre-existing RG wind and the photo-ionization from the central source did not encountered sudden discontinuities prior to switch-off of the nuclear burning; (2) the 2021 spectral evolution is similar to that of the 2006 eruption, with a mirror-appearance of the triple-peaked line profiles (blue peak brighter than red in 2006, the opposite in 2021); (3) the evolution of the triple-peaked profiles progressed similarly through different excitation and ionization degrees, suggesting an origin in a bipolar outflow nested to an equatorial torus; (4) the time-behavior of coronal emission lines appears quite smooth, both in terms of radiated flux as well as evolution of the triple-peaked profiles, with a plateau at maximum lasting up to about day 87; (5) there seems to exist within RS Oph two distinct types of ejecta: one fast moving and producing Gaussian-like line profiles (primarely [NII] and [OIII]), that keep expanding at FWHM=1000 km/s with no sign of ongoing deceleration during the two months leading up to Solar conjunction, and slower moving ejecta giving rise to the triple-peaked line profiles (HeI, HeII, coronal lines, and also Balmer lines at later times), for which the separation in velocity of blue and red peaks is still shrinking at the time of Solar conjunction when it reaches an average of 330 km/s; (6) the "symbiotic band" at 6825 Ang, due to Raman scattering of OVI 1032 by neutral hydrogen, appears simultaneously with the coronal lines: its very presence indicates that a sizeable part of the wind of the red giant has remained neutral during the development of coronal lines., Comment: 16 pages, 11 figures

Any white dwarf or neutron star that accretes enough material from a red giant companion, such that this interaction can be detected at some wavelength, is currently termed Symbiotic Star (typical P(orb)=2-3 years). In the majority of ~400 known systems, the WD burns nuclearly at its surface the accreted material, and the resulting high temperature (T(eff)=10(^5)~K) and luminosity (L(hot)=10(^3)-10(^4) Lsun) allow ionization of a large fraction of the cool giant's wind, making such symbiotic stars easily recognizable through the whole Galaxy and across the Local Group. X-ray observations are now revealing the existence of a parallel (and larger ?) population of optically-quiet, accreting-only symbiotic stars. Accretion flows and disks, ionization fronts and shock, complex 3D geometries and new evolution channels are gaining relevance and are reshaping our understanding of symbiotic stars. We review the different types of symbiotic stars currently in the family and their variegated outburst behaviors through an unified evolution scheme connecting them all., Invited Review, published in "The Impact of Binary Stars on Stellar Evolution", G. Beccari and M.J. Boffin eds., Cambridge Univ. Press., Cambridge Astrophysical Series vol. 54, pag. 77 (2019). Proceedings of a Conference held on 3-7 July 2017, at ESO Headquarters, Garching, Germany

We have been monitoring, at high cadence, the photometric and spectroscopic evolution of VES 263 following the discovery in 2018 of a brightening labeled as event Gaia-18azl. VES 263 is so far a neglected emission-line object discovered in the 1960s on objective prism plates, tentatively classified as a semi- regular AGB cool giant by automated analysis of ASASSN lightcurves. We have discovered that VES 263 is a bonafide massive pre-Main Sequence object (~12 Msun), of the Herbig AeBe type. It is located at 1.68+/-0.07 kpc distance, within the Cyg OB2 star-forming region, and it is highly reddened (E(B-V)=1.80+/-0.05) by interstellar extinction. In quiescence, the spectral energy distribution is dominated by the 20, 000 K photospheric emission from the central B1II star, and at wavelenghts >=6 micron by emission from circumstellar warm dust (Tdust up to 400 K). The 2018-19 eruption was caused by a marked brightening of the accretion disk around the B1II star as traced by the evolution with time of the integrated flux and the double-peaked profile of emission lines. At the peak of the eruption, the disk has a bulk temperature of ~7500 K and a luminosity L>=860 Lsun, corresponding to a mass accretion rate >=1.1x10(-5) Msun/yr. Spectroscopic signature of possible bipolar jets >(at -700 and +700 km/s) of variable intensity are found. We have reconstructed from Harvard, Moscow and Sonneberg photographic plates the photometric history of VES 263 from 1896 to 1995, showing through 1953-1969 a state much brighter than current eruption.

The known FUOri- type young eruptive stars are exceedingly rare(a dozen or so confirmed objects)and 2MASSJ06593158-0405277, with its 2014 outburst, is likely the latest addition to the family. All members have displayed just one such eruption in the rrecorded history, an event lasting for decades. To test the FUOri nature of 2MASSJ06593158-0405277, we have reconstructed its photometric history by measuring its brightness on Harvard photographic plates spanning the time interva 1899–1989. No previous large amplitude eruption similar to that intiated in 2014 has been found, as in bona fide FUOri-type objects. The median value of the brightness inquiescence of 2MASSJ06593158-0405277 is B=15.5, with the time interva l935–1950 characterized by a large variability (∼1 mag amplitude)that contrasts with the remarkable photometric stability displayed at later epochs.The variability during 1935–1950 can either be ascribed to some TTau like activity of 2MASSJ06593158-0405277 itself or to the also young and fainter star 2MASSJ06593168-0405224 that lies 5 arc sec to the North and forms an unresolved pair at the astrometric scale of Harvard photographic plates.

The Asiago plate archive has been searched for old plates covering the region of the sky containing Nova Del 2013 (V339 Del). The brightness of the progenitor was measured against a deep BVRI photometric sequence that we calibrated on purpose. The mean brightness of the progenitor on Asiago plates is =17.27 and =17.6, for a mean color (B-V) = -0.33. The recorded total amplitude of variation in B band is 0.9 mag. Color and variability are in agreement with a progenitor dominated by the emission from an accretion disc. The progenitor was marginally detected also by the APASS all sky survey on April 2012. We have stacked the CCD images from three individual visits and measured the progenitor at B=17.33+/-0.09 and V=17.06+/-0.10 mag., IBVS 6087

We reconstructed photometric histories of symbiotic stars and novae from direct inspection and measurement of photographic plates preserved at historical archives. We have completed the digging of the rich Asiago archive, and have started working on the Harvard plate stack, while other plate collections should be added soon. For homogeneity, we use the same UBVRC IC photometric comparison sequences used in current CCD observations. This data harvest has permitted the discovery of past undetected outbursts and secular trends, or to derive previously unknown orbital periods and recurrence times, which are essential to constrain the nature of these capricious and variegated active binaries.

Dani su rezultati pretrage progenitora Nova Cyg 2006 na fotopločama arhive opservatorija Asiago Sveučilišta u Padovi.

Two sets of grids of Kurucz ATLAS~9 model spectra are presented. The first one covers the GAIA spectral interval, while the second one which is still being computed covers the whole range from 2500 -- 10500 \AA. Both grids include parameters needed for realistic spectral simulation, e.g. stellar rotation and are computed at R=20000 and lower spectral resolutions. They can be useful for preparation of the GAIA and RAVE missions and also for a general radial velocity correlation work, Comment: 6 pages, 3 figures; to be published in GAIA spectroscopy, Science and Technology, ASP Conference Series, U.Munari (ed.)

High resolution (R~20,000), high signal-to-noise (S/N~100) spectra were collected for ~40 symbiotic stars with the Asiago echelle spectrograph over the same 8480-8740 Ang wavelength range covered by the ESA Cornerstone mission GAIA, centered on the near-IR CaII triplet and the head of the Paschen series. A large number (~140) of cool MKK giant and supergiant templates were observed with the same instrumentation to serve as a reference and classification grid. The spectra offer bright prospects in classifying and addressing the nature of the cool component of symbiotic stars (deriving T(eff), log g, [Fe/H], [alpha/Fe], V(rot)sin i both via MDM-like methods and syntetic atmosphere modeling) and mapping the physical condition and kinematics of the gas regions responsible for the emission lines., to appear in the proceedings of "Symbiotic stars probing stellar evolution", R.L.M. Corradi, J. Mikolajewska, T.J. Mahoney eds., ASP Conference Series, 2002, in press

Deep, wide-range and accurate UBVRI photometric sequences have been established around more than 80 symbiotic stars, to assist current photometry as well as measurement of old photographic plates. Sequences for 40 symbiotic stars have already been published; the observations for the others have already been secured., To appear in the proceedings of "Symbiotic stars probing stellar evolution", R.L.M. Corradi, J. Mikolajewska and T.J. Mahoney eds., ASP Conference Series, 2002, in press

We present the results of digging the rich archive plate of the Asiago observatory for symbiotic stars. A first bunch of objects have been located and measured on 1237 plates: AS 323, Ap 3-1, CM Aql, V1413 Aql (=AS 338), V443 Her, V627 Cas (=AS 501), V919 Sgr, Hen 2-468, QW Sge, LT Del, V407 Cyg, K 3-9, V335 Vul, FG Ser and Draco C-1. The results are published in Munari et al. (2001, A\&A 370, 503 ; 2002 astro-ph/0202118). Their brightness has been estimated against the $UBV(IR)_{;C};$ photometric sequences calibrated by Henden and Munari (2000 A\&A 372, 145 ; 2001 A\&AS 143, 343). The program aims are twofold. First, to contribute the Asiago data to the community interested in reconstructing historical lightcurves of symbiotic stars. Second, to derive physical information and parameters like orbital periods, presence of eclipses, tidal distortions, etc. Historical data have allowed for the first time the determination of the orbital periods of Hen 2-468 (774 days), QW Sge (390.5 days), CM Aql (P=1058 days) and AS 323 (197.6 days) which was also discovered to be quite probably an eclipsing system with the shortest known orbital period among symbiotic stars. A significant improvement in the orbital period of LT Del (456.6 days) was obtained too. The lightcurves of the other program stars turned out to provide precious information on previously unknown outbursts, firmer mapping of pulsation cycles, secular trend of their cool components.

We present accurate and deep UBVRI photometric sequences for an additional 20 symbiotic stars. As for the 20 targets of Paper I, the sequences extend over wide brightness and color ranges, and are suited to cover both quiescence and outburst phases. The sequences are intended to assist both present time photometry as well as measurement of photographic plates from historical archives., A&A, in press

Astrofizički opservatorij Asiago Sveučilišta u Padovi posjeduje jedan od najbogatijih i najstarijih europskih arhiva fotografskih ploča. Osobito je značajan za istraživanje simbiotskih zvijezda, budući da pripadnice ove nehomogene skupine eruptivnih dvojnih zvijezda manifestiraju svoju promjenljivost u vremenskim razmacima dugim od nekoliko godina do nekoliko desetljeća. S ciljem statističkog pristupa istraživanju simbiotskog fenomena pokrenut je program pretraživanja arhiva u potrazi za snimcima 68 objekata, koji čine skoro polovinu do danas identificiranih simbiotskih zvijezda. 27 zvijezda iz programa locirano je na više od 3000 fotoploča snimljenih dvama Schmidtovim teleskopima od 1958. do 1998. godine. Precizno određivanje njihova prividnog sjaja obavljeno je pomoću UBV(RI)c fotometrijskih nizova Hendena i Munarija. Upotpunjene krivulje sjaja pojedinih zvijezda iz programa omogućile su točnije određivanje orbitalnih perioda i diskusiju o uzrocima njihove simbiotske prirode.

We report about a suprisingly good correlation between the equivalent width of the diffuse interstellar band (DIB) at 8620 Ang and the interstellar reddening. Such a correlation offers bright prospects in using the 8620 Ang DIB as a tracer of the exctinction through the Galaxy in the context of GAIA, approved Cornerstone mission by ESA.

The spectral signature of collimated bipolar jets have been discovered on high resolution spectra of Hen 3-1341 during the 1999 outburst, the first ever recorded for this symbiotic star. The jets show up as emission components at DeltaRV = 820 km/sec on both sides of the main emission lines. They were not present in quiescence. As a general rule for the jets from stellar objects, also those in Hen 3-1341 come together with evidence of mass loss via wind (strong P-Cyg profiles)., Comment: Accepted for publication as a Letter to the Editor in Astronomy and Astrophysics

Internal kinematics, spectroscopic binaries and galactic motion are investigated for the trapezium system BD+00.1617 (which lies at the heart of the young open cluster Bochum 2) by means on 73 high resolution Echelle+CCD spectra secured over the period 1994-98. Two of the three O-type member stars are found to be binaries on close and highly eccentric orbits of 6.8 and 11.0 day period. The spectra of the two binaries show large variations in the half-intensity and equivalent widths of the HeI absorption lines, which are intrinsic to the primaries and are not correlated to the orbital phase. Astrometric and radial velocities exclude that one of the component is leaving as a runaway star, but upper limits are still compatible with the trapezium evaporating at very low relative velocities. The projected rotational velocities of the three constituent O--type stars are low. This conforms to expectations from the high frequency of binaries. The observed radial velocity of Bochum 2 agrees with the Hron (1987) expression for the Galaxy rotation inside the latter's quoted errors., Comment: Astron.Astrophys., in press

The no-longer-eclipsing system SS Lac in the young open cluster NGC 7209 has been recently announced to show a constant radial velocity. Puzzled by this finding, we have monitored the system during 1997 obtaining 24 Echelle+CCD spectra over 8 orbital revolutions. Our spectra reveal a nice orbital motion with periodic splitting and merging of spectral lines from both components. An accurate orbit has been derived, together with individual masses of the stars. SS Lac presents a moderately eccentric orbit and a probably full synchronization between stellar rotation and orbital revolution., Comment: 5 pages, 2 figures, LaTeX, accepted for publication in Astron.Astrophys. Main Journal

The Asiago photographic archive has been searched for plates containing the symbiotic stars Hen 2-468, QW Sge, LT Del, V407 Cyg, K 3-9, V335 Vul, FG Ser and Draco C-1. A total of 635 plates imaging the program stars have been found and the brightness estimated using the Henden & Munari (2000) UBVRI photometric sequences. These historical data have allowed for the first time the determination of the orbital periods of Hen 2-468 (774 days) and QW Sge (390.5 days), a significant improvement in the orbital period of LT Del (465.6 days) and for V407 Cyg an evaluation of the Mira's pulsation period and complex lightcurve shape in the red (R and I bands). Some previously unknown outbursts have been discovered too. (Paper I: Munari et al. 2001, A&A 370, 503), A&A, in press