A&A 383, 188-196 (2002)
DOI: 10.1051/0004-6361:20011724

A multi-epoch spectrophotometric atlas of symbiotic stars^,,

U. Munari^1,2 - T. Zwitter³

1 - Osservatorio Astronomico di Padova, Sede di Asiago, 36032 Asiago (VI), Italy
2 - CISAS - Centro Inter-Dipartimentale per Studi ed Attività Spaziali, Univ. di Padova, Italy
3 - University of Ljubljana, Department of Physics, Jadranska 19, 1000 Ljubljana, Slovenia

Received 9 October 20001 / Accepted 22 November 2001

Abstract
A multi-epoch, absolute-fluxed spectral atlas extending from about 3200 to 9000 Å is presented for 130 symbiotic stars, including members of the LMC, SMC and Draco dwarf galaxies. The fluxes are accurate to better than 5% as shown by comparison with Tycho and ground-based photometric data. The spectra of 40 reference objects (MKK cool giant standards, Mira and Carbon stars, planetary nebulae, white dwarfs, hot sub-dwarfs, Wolf-Rayet stars, classical novae, VV Cep and Herbig Ae/Be objects) are provided to assist the interpretation of symbiotic star spectra. Astrometric positions and counterparts in astrometric catalogues are derived for all program symbiotic stars. The spectra are available in electronic form from the authors.

Key words: stars: binaries: symbiotic - atlases

1 Introduction

Allen's (1984) atlas offered the first comprehensive spectroscopic view of symbiotic stars. It included spectra covering the 3400-7500 Å range for 114 objects (validated and possible, corresponding to 72% of the total number known at the time), which however were not fluxed, of low resolution and low dynamic range. Nevertheless, Allen's catalogue has been extensively used in all studies of symbiotic stars, even in those concerning single objects, because its single-epoch spectra could be compared with later observations in order to study the marked spectral variability of these binaries.

Other compilations of symbiotic star optical spectra are available. The larger ones since Allen's atlas are Blair et al. (1983; 16 objects, absolute fluxes), Ipatov & Yudin (1986; 14, absolute), Kenyon & Fernandez-Castro (1987; 11, absolute), Acker et al. (1988; 10, relative), Múrset et al. (1996; 12, absolute), Gutierrez-Moreno et al. (1999; 14, absolute) and Medina Tanco & Steiner (1995; 45, relative). Meier et al. (1994) assembled an atlas of ultraviolet IUE spectra for 32 symbiotic stars, Schulte-Ladbeck (1988) of 16 objects in the near-IR and Schild et al. (1992) of 8 objects in the IR. Van Winckel et al. (1993) surveyed emission line profiles for 59 objects and Ivison et al. (1994) for 35. Pereira et al. (1999) presented Bowen-fluorescence dominated blue spectra for 8 symbiotic stars and Schmid & Schild (1994) surveyed Raman-scatter dominated red spectra for 15 objects.

Here we present the largest optical spectroscopic atlas of symbiotic stars since Allen's one. Compared to Allen's atlas, our spectra cover a comparable number of objects (130 in all, 75 observed from ESO, 40 from Asiago, and 15 from both places) but are better resolved , extend over a wider wavelength range, offer a higher dynamical range, are absolutely fluxed, are multi-epoch (half of the targets re-observed one or more times over a three year period), and are available in electronic form (from the authors upon request).

The spectra presented in this atlas are planned to become the input data for future follow-up studies:
- given the high accuracy of the absolute fluxes and the wide wavelength range covered, optical magnitudes will be derived from the spectra and combined into a unique multi-epoch UBV(RI)$_{\rm C}$ photometric catalogue with the results of CCD photometry of 60 symbiotic stars obtained by Henden & Munari (2000, 2001, 2002) while calibrating their comparison sequences;
- the rich emission line spectrum of symbiotic stars will be studied in a global approach;
- properties of the cool giants will be derived from the absorption spectrum in the red region.

	Figure 1: The spectrum of the symbiotic star RR Tel. This is an example for the Figs. 4-256 available electronically only.
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Table 1: List of program stars and the journal of observations, separately for ESO and Asiago observations.

 

Table 1: continued.

 

Table 1: continued.

2 The data

The list of program stars and the journal of observations is given in Table 1. The number of symbiotic stars (validated and probable) observed for this atlas is 130, with a total of 213 spectra presented in Figs. 4-216. Spectra of 40 reference stars are given in Figs. 217-256, with Table 2 listing their relevant properties. Figure 1 gives an example of Figs. 4-256 available electronically only. Of the 90 symbiotic stars observed from ESO, 22 have been re-observed about one year later. Fifty-five are instead the symbiotics observed from Asiago, 21 of which were re-observed once, 9 twice and 1 three times over a two and a half year period. For some systems our observations document the spectral changes induced by an outburst state, as for CL Sco (during the 1995 quiescence in Fig. 49, and at 1996 outburst in Fig. 50), or their interplay with the pulsation activity of the cool giant, as for the carbon symbiotic Mira UV Aur (at Mira's minimum in Fig. 124, and at Mira's maximum in Fig. 125).

The program stars have been selected among those listed in Allen's (1984) catalogue and those discovered later (and summarized in the new catalogue of symbiotic stars by Belczynski et al. 2000), including objects from the Meyssonnier & Azzopardi (1993) survey of SMC.

The object names (as given in Table 1 and the first column of Table 3) are sometimes different from those used in the literature, because either (i) a variable star name has been assigned since (for example V1413 Aql for AS 338), or (ii) there have been re-organizations in the name coding within SIMBAD (for example, He 2-468 was replaced by Hen 2-468, or Hen 1591 is now Hen 3-1591). A list of correspondences is given in Table 3, where Col. 2 contains Allen (1984) names for the systems renamed subsequently.

The spectrophotometric observations have been performed with B&C + CCD spectrographs at ESO and Asiago. All spectra have been reduced with the IRAF software package. Standard procedures (including bias and flat field correction, wavelength and flux calibration) have been applied. Cosmic rays on the stellar tracing were cleaned manually on the extracted spectrum after inspection of the original two dimensional frames. For the vast majority of the program stars we have obtained more than one spectrum per night (with the aim of appropriately exposing the continuum as well as avoiding saturation of the strongest emission lines), and their inter-comparison greatly assisted during the manual cleaning of cosmic-rays.

2.1 Astrometry

Historically inaccurate or erroneous coordinates of several symbiotic stars are still present in the current literature. Moreover, correspondence between symbiotic stars and entries in astrometric catalogues has not been systematically explored yet. The latter is an important task because, once the correspondence is established, coordinates of symbiotic stars will be automatically improved every time the catalogues are re-calibrated (like USNO-A1 that has been recalibrated into USNO-A2 when the Hipparcos/Tycho reference stars have become available) or cross-referenced toward newer and higher precision catalogues.

Correspondence with sources in astrometric catalogues is established in Table 3 (last column) for all the program stars. Help has been provided by the Aladin graphical interface at CDS (http://aladin.u-strasbg.fr/aladin.gml) that allows overplotting of astrometric catalogues over the digitized DSS-I and DSS-II plates. The astrometric identification has been searched for and taken from the following catalogues, in order of preference: Hipparcos, Tycho-2, USNO-A2.0, GSC-1, 2MASS. Only 6 objects lack any astrometric identification, while 14 and 24 objects are included in the Hipparcos and Tycho-2 catalogues, respectively.

Coordinates of program stars in Table 1 have not been adapted or re-processed from the existing literature, but re-compiled from scratch. Hender & Munari (2000, 2001) give astrometrically measured accurate positions for 40 of our program stars (linked to the USNO-A2.0 reference system). For the remaining targets the positions as given in the appropriate astrometric catalogues (following identifications in Table 3) have been adopted. For the 6 objects without an entry in the surveyed astrometric catalogues, coordinates have been measured by us on the digitized DSS-II plates (or, if not available, on the DSS-I ones). All coordinates are on J2000.0 equinox, but epochs are those of the corresponding catalogues (this should not be a major concern given the minimal proper motions typical for most symbiotic stars).

2.2 ESO observations

The ESO observations have been performed with the B&C + CCD spectrograph at the 1.5 m telescope under photometric conditions (sparse data from non optimal nights have not been used in the present atlas). We used a 400 l/mm grating (# 25) and a 2 arcsec slit, always aligned along the parallactic angle for pointings at zenital distances larger than 35$^\circ$. The CCD was a $2048\times2048$, 15 $\mu$m size, thinned and back-illuminated to enhance UV sensitivity. The dispersion was $\sim$2.5 Å/pix, with a FWHM(PSF) $\sim$ 2 pixels. The covered spectral range changes somewhat from one observing run to another, with the extremes of 3200-8900 and 3400-9100 Å. The seeing during the observing nights was always smaller than the slit width (as can be derived from the simultaneous absolute measurements with the La Silla Meteo Monitor and from the measured FWHM perpendicular to the dispersion on the recorded stellar spectra). For a non-marginal part of the time the seeing was better than 1 arcsec. Several spectrophotometric standards were observed each night in order to achieve absolute flux calibration and monitor stable transparency conditions.

	Figure 2: Comparison of V magnitudes of symbiotic stars as estimated by amateur astronomers (VSNET, VSOLJ, AFOEV databases) and as derived from flux calibrated spectra in this atlas. To identify the given symbiotic star and its particular spectrum, the upper row in each panel lists the corresponding figure number (cf. Table 1). See text for details (Sect. 2.5).
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	Figure 3: Comparison of $V_{\rm T}$ magnitudes and ( $B_{\rm T} - V_{\rm T}$) colors of template stars in Table 2 as measured by Hipparcos/Tycho and as derived from spectra in this atlas. See text for details (Sect. 2.5).
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2.3 Asiago observations

The Asiago observations were secured with the Boller & Chivens spectrograph attached to the 1.82 m telescope operated by Osservatorio Astronomico di Padova atop of Mount Ekar (Asiago, Italy), during nights of suitable photometric conditions. The detector was a Thompson TH7882 UV-coated CCD, $580\times 388$ pixels of 23 $\mu$m size. We used a 150 ln/mm grating giving a dispersion of 7.5 Å/pixel, generally covering the wavelengths 3350-7550 Å (exact limits variable according to the observing runs). The slit width was $\sim$2.0 arcsec, giving a FHWM(PSF) $\sim$ 2 pixels. When the object's zenith distance exceeded 45$^\circ$, the slit was aligned along the parallactic angle. Each night at least four spectrophotometric standard stars were observed more than once at different airmasses for flux calibration.

2.4 Reference objects

A number of spectra of reference objects have been secured with the same instrumentation during symbiotic star observing runs. The reference objects include MKK cool giant standards, Miras, planetary nebulae, Wolf Rayet stars, white dwarfs, hot sub-dwarf, classical novae, and are intended to assist inspection and interpretation of symbiotic star spectra. They are listed in Table 2 and their spectra are presented in Figs. 217-256.

2.5 Flux accuracy

It appears appropriate to quantify the accuracy of absolute fluxes in this atlas. For symbiotic stars no optical photometry was carried out simultaneously with the spectroscopic observations. However, a number of program symbiotic stars are regularly observed by several organizations of amateur astronomers. We have consulted the on-line databases of VSNET, VSOLJ and AFOEV and found useful data to support comparison with 70 of the spectra presented in this atlas (49 Asiago spectra and 21 ESO spectra, reflecting the predominance of amateurs in the northern hemisphere and higher brightness of average symbiotic stars known in the northern hemisphere). When possible, the amateurs' lightcurves have been interpolated/extrapolated to derive the visual magnitude for the date of the given spectral observation. In a few cases an estimate was found in the amateurs' archives for the exact date of the spectral observations. Such estimates have been adopted unless an eye inspection of the whole light-curve rendered them unreliable.

The V magnitude was derived from our spectra by convolving them with the V band-pass profile (taken from Azusienis & Straizys 1969). The comparison between the spectroscopic and amateurs' V magnitudes is presented in Fig. 2 separately for the Asiago and ESO data. The comparison gives for the ESO spectra:

$$% V_{\rm spectrum}\ -\ V_{\rm amateurs}\ =\ -0.06;\ \ \ \ \sigma\ =\ 0.21$$ (1)

and similarly for the Asiago spectra:

$$% V_{\rm spectrum}\ -\ V_{\rm amateurs}\ =\ -0.05;\ \ \ \ \sigma\ =\ 0.19.$$ (2)

The offset is small and can be easily accounted for by a number of possibilities, the first and the most obvious one being the difference between the eye response and the V band profile.

ESO and Asiago observations appear equally accurate, as seen in Figs. 2 and 3, with an average 0.20 mag scatter that deserves some comment. Several mechanisms contribute to it, including [a] errors in the comparison sequences used by amateurs ( $\sigma_{\rm cs}$), [b] errors in estimating the magnitude by the amateurs and uncertainties in interpolating/extrapolating their lightcurve to the desired date ( $\sigma_{\rm est}$), [c] day-by-day random variability of symbiotic stars ( $\sigma_{\rm var}$), and obviously [d] the errors in fluxing our spectra ( $\sigma_{\rm flux}$). Because these errors are unrelated and follow normal distributions we write

$$% \sigma^2\ =\ (0.20)^2\ =\ \sigma_{\rm cs}^2\ +\ \sigma_{\rm est}^2\ +\ \sigma_{\rm var}^2\ +\ \sigma_{\rm flux}^2.$$ (3)

Based on common experience it may be assumed that $\sigma_{\rm cs} \geq 0.05$, $\sigma_{\rm est} \geq 0.15$, and $\sigma_{\rm var} \sim 0.1$ ( $\sigma_{\rm cs}=0.05$ is obviously an underestimate, at least because magnitudes of comparison stars on amateur finding charts are given to one decimal figure only). So $\sigma_{\rm flux}\ \leq 6\%$, i.e. the fluxes of each individual spectrum are on the average accurate better than 6%. This is in fair agreement with results of inter-calibrations of spectrophotometric standard stars observed every night that suggest an accuracy of 5% or better.

Certain points in Fig. 3 are marked with open circles and triangles. The open circles refer to HM Sge and V1016 Cyg that have spectra resembling planetary nebulae. Minimal differences between the V band and eye response curves around the immensely strong H$\alpha$ and [OIII] lines fully account for the $\sim$0.7 mag systematic difference of both Asiago and ESO spectra versus amateurs' estimates. The open triangles refer to V1413 Aql that shows the same $\sim$0.8 mag systematic difference between the Asiago and ESO spectra vs. amateurs' estimates: the reason may be an error in the comparison sequence around V1413 Aql used by the amateurs.

Another independent way to estimate the flux accuracy is offered by the spectra of the reference objects listed in Table 2. Selecting those not carrying a variable star name among those observed by Hipparcos/Tycho, we found

$$% V_{\rm T}^{\rm spectra}\ -\ V_{\rm T}^{\rm Tycho}\ = -0.06;\ \ \ \ \sigma\ =\ 0.08$$ (4)

$$(B-V)_{\rm T}^{\rm spectra} - (B-V)_{\rm T}^{\rm Tycho} = +0.03;\ \ \ \ \sigma\ =\ 0.03.$$ (5)

Here the spectra were convolved with the $B_{\rm T}$ and $V_{\rm T}$ band profiles as given in the Hipparcos Catalogue (ESA SP-1200, June 1997, p. 42; slightly modified transmission profiles are suggested by Bessell 2000). The uncertainties in the shutter aperture time ($\sim$0.1 s in both Asiago and ESO observations) become notable in the observations of the bright template stars in Table 2 with an average exposure time of only 2.5 s. Also, non-perfect placement of such bright objets on the slit, which is compensated for faint objects by guiding, may contribute to the scatter in Eq. (5). Finally, it is worth remembering that Tycho data for bright stars are accurate to 0.012 mag in $V_{\rm T}$ and 0.02 mag in $(B-V)_{\rm T}$.

In light of these considerations it seems safe to argue that the fluxes in this atlas are generally correct within

$$% \sigma_{\rm flux} \lower.5ex\hbox{$\; \buildrel < \over \sim \;$ }5\%$$ (6)

at least for the B, V and R band wavelength ranges. A lower accuracy is probable for faint red objects at $\lambda \leq 3800$ Å or for pure emission line spectra at $\lambda \geq 8700$ Å.

3 The atlas

Each spectral observation listed in Tables 1 and 2 is presented by a separate figure. The format of the figures is identical to Fig. 1. UT dates are in the DD.dd/MM/YY format.

At upper right a full-scale, compressed view of the whole recorded spectrum is given, and the units for absolute fluxes are indicated. The same units are valid for the other panels that present zoomed-in portions of the spectrum.

For ESO spectra the first zoomed-in panel always runs from 3200 to 5250 Å, the second from 5150 to 7200 Å, and the third from 7100 to 9150 Å. For Asiago spectra, given the shorter wavelength range covered, two zoomed-in panels suffice, the first from 3250 to 5600 Å, the second from 5350 to 7600 Å.

Stronger emission lines are generally truncated in the zoomed-in panels to emphasize the visibility of finer details. The full height of emission lines can be read from the compressed view of the whole spectrum at the upper right.

References

 
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• Azusienis, A., & Strayzys, V. 1969, Sov. Astron., 13, 316 In the text NASA ADS  
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• Bessell, M. S. 2000, PASP, 112, 961 In the text NASA ADS  
• Blair, W. P., Feibelman, W. A., Michalitsianos, A. G., & Stencel, R. E. 1983, ApJS, 53, 573 In the text NASA ADS  
• Gutiérrez-Moreno, A., Moreno, H., & Costa, E. 1999, PASP, 111, 571 In the text NASA ADS  
• Ipatov, A. P., & Yudin, B. F. 1986, A&AS, 65, 51 In the text NASA ADS  
• Ivison, R. J., Bode, M. F., & Meaburn, J. 1994, A&AS, 103, 201 In the text NASA ADS  
• Henden, A., & Munari, U. 2000, A&AS, 143, 343 In the text NASA ADS  
• Henden, A., & Munari, U. 2001, A&A, 372, 145 In the text NASA ADS  
• Henden, A., & Munari, U. 2002, A&A, to be submitted In the text  
• Kenyon, S. J. 1986, The symbiotic stars (Cambridge University Press)  
• Kenyon, S. J., & Fernandez-Castro, T. 1987, AJ, 93, 938 In the text NASA ADS  
• Meyssonnier, N., & Azzopardi, M. 1993, A&AS, 102, 451 In the text NASA ADS  
• Medina Tanco, G. A., & Steiner, J. E. 1995, AJ, 109, 1770 In the text NASA ADS  
• Meier, S. R., Kafatos, M., Fahey, R. P., & Michalitsianos, A. G. 1994, ApJS, 94, 183 In the text NASA ADS  
• Mürset, U., Schild, H., & Vogel, M. 1996, A&A, 307, 516 In the text NASA ADS  
• Pereira, C. B., de Araújo, F. X., & Landaberry, S. 1999, MNRAS, 309, 1074 In the text NASA ADS  
• Schild, H., Boyle, S. J., & Schmid, H. M. 1992, MNRAS, 258, 95 In the text NASA ADS  
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• Van Winckel, H., Duerbeck, H. W., & Schwarz, H. E. 1993, A&AS, 102, 401 In the text NASA ADS

 

Online Material

Figure 4: ESO 1.5 m + B&C spectrum of SMC 1.

Figure 5: ESO 1.5 m + B&C spectrum of SMC 2.

Figure 6: ESO 1.5 m + B&C spectrum of SMC 3.

Figure 7: ESO 1.5 m + B&C spectrum of LHA 115-N 60.

Figure 8: ESO 1.5 m + B&C spectrum of Lin 358.

Figure 9: ESO 1.5 m + B&C spectrum of LHA 115-N 73.

Figure 10: ESO 1.5 m + B&C spectrum of StHA 32.

Figure 11: ESO 1.5 m + B&C spectrum of LMC 1.

Figure 12: ESO 1.5 m + B&C spectrum of LHA 120-N 67.

Figure 13: ESO 1.5 m + B&C spectrum of LHA 120-N 67.

Figure 14: ESO 1.5 m + B&C spectrum of Sanduleak's.

Figure 15: ESO 1.5 m + B&C spectrum of LHA 120-S 63.

Figure 16: ESO 1.5 m + B&C spectrum of WRAY 15-157.

Figure 17: ESO 1.5 m + B&C spectrum of RX Pup.

Figure 18: ESO 1.5 m + B&C spectrum of AS 201.

Figure 19: ESO 1.5 m + B&C spectrum of KM Vel.

Figure 20: ESO 1.5 m + B&C spectrum of V366 Car.

Figure 21: ESO 1.5 m + B&C spectrum of SS 29.

Figure 22: ESO 1.5 m + B&C spectrum of BI Cru.

Figure 23: ESO 1.5 m + B&C spectrum of SS 38.

Figure 24: ESO 1.5 m + B&C spectrum of Hen 3-863.

Figure 25: ESO 1.5 m + B&C spectrum of Hen 3-863.

Figure 26: ESO 1.5 m + B&C spectrum of V840 Cen.

Figure 27: ESO 1.5 m + B&C spectrum of V840 Cen.

Figure 28: ESO 1.5 m + B&C spectrum of Hen 3-905.

Figure 29: ESO 1.5 m + B&C spectrum of Hen 3-905.

Figure 30: ESO 1.5 m + B&C spectrum of V852 Cen.

Figure 31: ESO 1.5 m + B&C spectrum of V835 Cen.

Figure 32: ESO 1.5 m + B&C spectrum of IV Vir.

Figure 33: ESO 1.5 m + B&C spectrum of IV Vir.

Figure 34: ESO 1.5 m + B&C spectrum of Hen 2-127.

Figure 35: ESO 1.5 m + B&C spectrum of Hen 2-127.

Figure 36: ESO 1.5 m + B&C spectrum of Hen 3-1092.

Figure 37: ESO 1.5 m + B&C spectrum of Hen 3-1092.

Figure 38: ESO 1.5 m + B&C spectrum of HD 330036.

Figure 39: ESO 1.5 m + B&C spectrum of HD 330036.

Figure 40: ESO 1.5 m + B&C spectrum of Hen 2-139.

Figure 41: ESO 1.5 m + B&C spectrum of T CrB.

Figure 42: ESO 1.5 m + B&C spectrum of V347 Nor.

Figure 43: ESO 1.5 m + B&C spectrum of V347 Nor.

Figure 44: ESO 1.5 m + B&C spectrum of UKS Ce-1.

Figure 45: ESO 1.5 m + B&C spectrum of Hen 2-171.

Figure 46: ESO 1.5 m + B&C spectrum of Hen 2-171.

Figure 47: ESO 1.5 m + B&C spectrum of Hen 2-176.

Figure 48: ESO 1.5 m + B&C spectrum of AS 210.

Figure 49: ESO 1.5 m + B&C spectrum of CL Sco.

Figure 50: ESO 1.5 m + B&C spectrum of CL Sco.

Figure 51: ESO 1.5 m + B&C spectrum of Hen 3-1342.

Figure 52: ESO 1.5 m + B&C spectrum of Hen 3-1342.

Figure 53: ESO 1.5 m + B&C spectrum of Hen 3-1410.

Figure 54: ESO 1.5 m + B&C spectrum of V2116 Oph.

Figure 55: ESO 1.5 m + B&C spectrum of Th 3-30.

Figure 56: ESO 1.5 m + B&C spectrum of Th 3-30.

Figure 57: ESO 1.5 m + B&C spectrum of H 1-25.

Figure 58: ESO 1.5 m + B&C spectrum of RT Ser.

Figure 59: ESO 1.5 m + B&C spectrum of V2110 Oph.

Figure 60: ESO 1.5 m + B&C spectrum of H 1-36.

Figure 61: ESO 1.5 m + B&C spectrum of RS Oph.

Figure 62: ESO 1.5 m + B&C spectrum of WRAY 16-312.

Figure 63: ESO 1.5 m + B&C spectrum of V745 Sco.

Figure 64: ESO 1.5 m + B&C spectrum of AS 255.

Figure 65: ESO 1.5 m + B&C spectrum of AS 255.

Figure 66: ESO 1.5 m + B&C spectrum of SS 122.

Figure 67: ESO 1.5 m + B&C spectrum of H 2-38.

Figure 68: ESO 1.5 m + B&C spectrum of SS 129.

Figure 69: ESO 1.5 m + B&C spectrum of SS 129.

Figure 70: ESO 1.5 m + B&C spectrum of Hen 3-1591.

Figure 71: ESO 1.5 m + B&C spectrum of YY Her.

Figure 72: ESO 1.5 m + B&C spectrum of FG Ser.

Figure 73: ESO 1.5 m + B&C spectrum of Hen 3-1674.

Figure 74: ESO 1.5 m + B&C spectrum of Hen 3-1674.

Figure 75: ESO 1.5 m + B&C spectrum of V3929 Sgr.

Figure 76: ESO 1.5 m + B&C spectrum of V3929 Sgr.

Figure 77: ESO 1.5 m + B&C spectrum of V3811 Sgr.

Figure 78: ESO 1.5 m + B&C spectrum of V4018 Sgr.

Figure 79: ESO 1.5 m + B&C spectrum of K 3-9.

Figure 80: ESO 1.5 m + B&C spectrum of StHA 154.

Figure 81: ESO 1.5 m + B&C spectrum of V4368 Sgr.

Figure 82: ESO 1.5 m + B&C spectrum of V4368 Sgr.

Figure 83: ESO 1.5 m + B&C spectrum of V1413 Aql.

Figure 84: ESO 1.5 m + B&C spectrum of Ap 3-1.

Figure 85: ESO 1.5 m + B&C spectrum of HM Sge.

Figure 86: ESO 1.5 m + B&C spectrum of V1016 Cyg.

Figure 87: ESO 1.5 m + B&C spectrum of RR Tel.

Figure 88: ESO 1.5 m + B&C spectrum of PU Vul.

Figure 89: ESO 1.5 m + B&C spectrum of PU Vul.

Figure 90: ESO 1.5 m + B&C spectrum of StHA 176.

Figure 91: ESO 1.5 m + B&C spectrum of LT Del.

Figure 92: ESO 1.5 m + B&C spectrum of ER Del.

Figure 93: ESO 1.5 m + B&C spectrum of V1329 Cyg.

Figure 94: ESO 1.5 m + B&C spectrum of CD -43.14304.

Figure 95: ESO 1.5 m + B&C spectrum of CD -43.14304.

Figure 96: ESO 1.5 m + B&C spectrum of StHA 190.

Figure 97: ESO 1.5 m + B&C spectrum of AG Peg.

Figure 98: ESO 1.5 m + B&C spectrum of R Aqr.

Figure 99: ESO 1.5 m + B&C spectrum of Ma 51.

Figure 100: ESO 1.5 m + B&C spectrum of Ma 250.

Figure 101: ESO 1.5 m + B&C spectrum of Ma 285.

Figure 102: ESO 1.5 m + B&C spectrum of Ma 642.

Figure 103: ESO 1.5 m + B&C spectrum of Ma 832.

Figure 104: ESO 1.5 m + B&C spectrum of Ma 966.

Figure 105: ESO 1.5 m + B&C spectrum of Ma 1591.

Figure 106: ESO 1.5 m + B&C spectrum of Ma 1858.

Figure 107: ESO 1.5 m + B&C spectrum of StHA 55.

Figure 108: ESO 1.5 m + B&C spectrum of V704 Cen.

Figure 109: ESO 1.5 m + B&C spectrum of V704 Cen.

Figure 110: ESO 1.5 m + B&C spectrum of V417 Cen.

Figure 111: ESO 1.5 m + B&C spectrum of V417 Cen.

Figure 112: ESO 1.5 m + B&C spectrum of V748 Cen.

Figure 113: ESO 1.5 m + B&C spectrum of HD 149427.

Figure 114: ESO 1.5 m + B&C spectrum of V1017 Sgr.

Figure 115: ESO 1.5 m + B&C spectrum of AS 325.

Figure 116: Asiago 1.82 m + B&C spectrum of EG And.

Figure 117: Asiago 1.82 m + B&C spectrum of EG And.

Figure 118: Asiago 1.82 m + B&C spectrum of AX Per.

Figure 119: Asiago 1.82 m + B&C spectrum of AX Per.

Figure 120: Asiago 1.82 m + B&C spectrum of V471 Per.

Figure 121: Asiago 1.82 m + B&C spectrum of V471 Per.

Figure 122: Asiago 1.82 m + B&C spectrum of BD Cam.

Figure 123: Asiago 1.82 m + B&C spectrum of BD Cam.

Figure 124: Asiago 1.82 m + B&C spectrum of UV Aur.

Figure 125: Asiago 1.82 m + B&C spectrum of UV Aur.

Figure 126: Asiago 1.82 m + B&C spectrum of BX Mon.

Figure 127: Asiago 1.82 m + B&C spectrum of BX Mon.

Figure 128: Asiago 1.82 m + B&C spectrum of MWC 560.

Figure 129: Asiago 1.82 m + B&C spectrum of NQ Gem.

Figure 130: Asiago 1.82 m + B&C spectrum of NQ Gem.

Figure 131: Asiago 1.82 m + B&C spectrum of RW Hya.

Figure 132: Asiago 1.82 m + B&C spectrum of IV Vir.

Figure 133: Asiago 1.82 m + B&C spectrum of T CrB.

Figure 134: Asiago 1.82 m + B&C spectrum of T CrB.

Figure 135: Asiago 1.82 m + B&C spectrum of T CrB.

Figure 136: Asiago 1.82 m + B&C spectrum of T CrB.

Figure 137: Asiago 1.82 m + B&C spectrum of AG Dra.

Figure 138: Asiago 1.82 m + B&C spectrum of AG Dra.

Figure 139: Asiago 1.82 m + B&C spectrum of AG Dra.

Figure 140: Asiago 1.82 m + B&C spectrum of Hen 3-1341.

Figure 141: Asiago 1.82 m + B&C spectrum of Draco C-1.

Figure 142: Asiago 1.82 m + B&C spectrum of Draco C-1.

Figure 143: Asiago 1.82 m + B&C spectrum of M 1-21.

Figure 144: Asiago 1.82 m + B&C spectrum of RT Ser.

Figure 145: Asiago 1.82 m + B&C spectrum of Pt 1.

Figure 146: Asiago 1.82 m + B&C spectrum of RS Oph.

Figure 147: Asiago 1.82 m + B&C spectrum of RS Oph.

Figure 148: Asiago 1.82 m + B&C spectrum of V343 Ser.

Figure 149: Asiago 1.82 m + B&C spectrum of V343 Ser.

Figure 150: Asiago 1.82 m + B&C spectrum of FG Ser.

Figure 151: Asiago 1.82 m + B&C spectrum of FG Ser.

Figure 152: Asiago 1.82 m + B&C spectrum of FG Ser.

Figure 153: Asiago 1.82 m + B&C spectrum of YY Her.

Figure 154: Asiago 1.82 m + B&C spectrum of YY Her.

Figure 155: Asiago 1.82 m + B&C spectrum of V443 Her.

Figure 156: Asiago 1.82 m + B&C spectrum of V443 Her.

Figure 157: Asiago 1.82 m + B&C spectrum of V443 Her.

Figure 158: Asiago 1.82 m + B&C spectrum of MWC 960.

Figure 159: Asiago 1.82 m + B&C spectrum of AS 327.

Figure 160: Asiago 1.82 m + B&C spectrum of FN Sgr.

Figure 161: Asiago 1.82 m + B&C spectrum of Pe 2-16.

Figure 162: Asiago 1.82 m + B&C spectrum of Pe 2-16.

Figure 163: Asiago 1.82 m + B&C spectrum of CM Aql.

Figure 164: Asiago 1.82 m + B&C spectrum of CM Aql.

Figure 165: Asiago 1.82 m + B&C spectrum of CM Aql.

Figure 166: Asiago 1.82 m + B&C spectrum of V919 Sgr.

Figure 167: Asiago 1.82 m + B&C spectrum of V1413 Aql.

Figure 168: Asiago 1.82 m + B&C spectrum of V1413 Aql.

Figure 169: Asiago 1.82 m + B&C spectrum of V1413 Aql.

Figure 170: Asiago 1.82 m + B&C spectrum of Ap 3-1.

Figure 171: Asiago 1.82 m + B&C spectrum of BF Cyg.

Figure 172: Asiago 1.82 m + B&C spectrum of BF Cyg.

Figure 173: Asiago 1.82 m + B&C spectrum of CH Cyg.

Figure 174: Asiago 1.82 m + B&C spectrum of CH Cyg.

Figure 175: Asiago 1.82 m + B&C spectrum of CH Cyg.

Figure 176: Asiago 1.82 m + B&C spectrum of HM Sge.

Figure 177: Asiago 1.82 m + B&C spectrum of QW Sge.

Figure 178: Asiago 1.82 m + B&C spectrum of QW Sge.

Figure 179: Asiago 1.82 m + B&C spectrum of QW Sge.

Figure 180: Asiago 1.82 m + B&C spectrum of CI Cyg.

Figure 181: Asiago 1.82 m + B&C spectrum of CI Cyg.

Figure 182: Asiago 1.82 m + B&C spectrum of V1016 Cyg.

Figure 183: Asiago 1.82 m + B&C spectrum of V1016 Cyg.

Figure 184: Asiago 1.82 m + B&C spectrum of PU Vul.

Figure 185: Asiago 1.82 m + B&C spectrum of PU Vul.

Figure 186: Asiago 1.82 m + B&C spectrum of PU Vul.

Figure 187: Asiago 1.82 m + B&C spectrum of LT Del.

Figure 188: Asiago 1.82 m + B&C spectrum of LT Del.

Figure 189: Asiago 1.82 m + B&C spectrum of LT Del.

Figure 190: Asiago 1.82 m + B&C spectrum of Hen 2-468.

Figure 191: Asiago 1.82 m + B&C spectrum of Hen 2-468.

Figure 192: Asiago 1.82 m + B&C spectrum of V1329 Cyg.

Figure 193: Asiago 1.82 m + B&C spectrum of V1329 Cyg.

Figure 194: Asiago 1.82 m + B&C spectrum of V407 Cyg.

Figure 195: Asiago 1.82 m + B&C spectrum of V407 Cyg.

Figure 196: Asiago 1.82 m + B&C spectrum of AG Peg.

Figure 197: Asiago 1.82 m + B&C spectrum of AG Peg.

Figure 198: Asiago 1.82 m + B&C spectrum of Z And.

Figure 199: Asiago 1.82 m + B&C spectrum of Z And.

Figure 200: Asiago 1.82 m + B&C spectrum of R Aqr.

Figure 201: Asiago 1.82 m + B&C spectrum of V641 Cas.

Figure 202: Asiago 1.82 m + B&C spectrum of V641 Cas.

Figure 203: Asiago 1.82 m + B&C spectrum of GH Gem.

Figure 204: Asiago 1.82 m + B&C spectrum of ZZ CMi.

Figure 205: Asiago 1.82 m + B&C spectrum of ZZ CMi.

Figure 206: Asiago 1.82 m + B&C spectrum of TX CVn.

Figure 207: Asiago 1.82 m + B&C spectrum of TX CVn.

Figure 208: Asiago 1.82 m + B&C spectrum of V503 Her.

Figure 209: Asiago 1.82 m + B&C spectrum of XX Oph.

Figure 210: Asiago 1.82 m + B&C spectrum of V335 Vul.

Figure 211: Asiago 1.82 m + B&C spectrum of V335 Vul.

Figure 212: Asiago 1.82 m + B&C spectrum of Hen 2-442.

Figure 213: Asiago 1.82 m + B&C spectrum of OY Cyg.

Figure 214: Asiago 1.82 m + B&C spectrum of V627 Cas.

Figure 215: Asiago 1.82 m + B&C spectrum of V627 Cas.

Figure 216: Asiago 1.82 m + B&C spectrum of V630 Cas.

Figure 217: ESO 1.5 m + B&C spectrum of HD 159876.

Figure 218: ESO 1.5 m + B&C spectrum of HD 171802.

Figure 219: ESO 1.5 m + B&C spectrum of HD 78791.

Figure 220: ESO 1.5 m + B&C spectrum of HD 93497.

Figure 221: ESO 1.5 m + B&C spectrum of HD 82734.

Figure 222: ESO 1.5 m + B&C spectrum of HD 112985.

Figure 223: ESO 1.5 m + B&C spectrum of HD 78647.

Figure 224: ESO 1.5 m + B&C spectrum of HD 92305.

Figure 225: ESO 1.5 m + B&C spectrum of HD 133216.

Figure 226: ESO 1.5 m + B&C spectrum of HD 118767.

Figure 227: ESO 1.5 m + B&C spectrum of LQ Sgr.

Figure 228: ESO 1.5 m + B&C spectrum of HD 51208.

Figure 229: ESO 1.5 m + B&C spectrum of EK TrA.

Figure 230: ESO 1.5 m + B&C spectrum of M 1-12.

Figure 231: ESO 1.5 m + B&C spectrum of M 1-13.

Figure 232: ESO 1.5 m + B&C spectrum of HD 136488.

Figure 233: ESO 1.5 m + B&C spectrum of HD 165763.

Figure 234: ESO 1.5 m + B&C spectrum of HD 50896.

Figure 235: ESO 1.5 m + B&C spectrum of HD 96548.

Figure 236: ESO 1.5 m + B&C spectrum of Nova Cen 1995.

Figure 237: ESO 1.5 m + B&C spectrum of Nova Cir 1995.

Figure 238: ESO 1.5 m + B&C spectrum of Nova Lup 1993.

Figure 239: ESO 1.5 m + B&C spectrum of BD +28.4211.

Figure 240: ESO 1.5 m + B&C spectrum of LTT 7987.

Figure 241: Asiago 1.82 m + B&C spectrum of HD 55052.

Figure 242: Asiago 1.82 m + B&C spectrum of HD 88639.

Figure 243: Asiago 1.82 m + B&C spectrum of HD 75958.

Figure 244: Asiago 1.82 m + B&C spectrum of HD 91810.

Figure 245: Asiago 1.82 m + B&C spectrum of HD 64960.

Figure 246: Asiago 1.82 m + B&C spectrum of HD 115521.

Figure 247: Asiago 1.82 m + B&C spectrum of HD 109896.

Figure 248: Asiago 1.82 m + B&C spectrum of HD 112300.

Figure 249: Asiago 1.82 m + B&C spectrum of HD 76830.

Figure 250: Asiago 1.82 m + B&C spectrum of HD 175865.

Figure 251: Asiago 1.82 m + B&C spectrum of Nova Aql 1993.

Figure 252: Asiago 1.82 m + B&C spectrum of Nova Cas 1993.

Figure 253: Asiago 1.82 m + B&C spectrum of Nova Cas 1995.

Figure 254: Asiago 1.82 m + B&C spectrum of VV Cep.

Figure 255: Asiago 1.82 m + B&C spectrum of V594 Cas.

Figure 256: Asiago 1.82 m + B&C spectrum of 4U 2206+54.