Contents

A&A 464, 1045-1047 (2007)
DOI: 10.1051/0004-6361:20066554

Interferometric observations of $\eta $ Carinae with VINCI/VLTI[*]
(Research Note)

P. Kervella

LESIA, UMR 8109, Observatoire de Paris-Meudon, 5 place Jules Janssen, 92195 Meudon Cedex, France

Received 12 October 2006 / Accepted 28 November 2006

Abstract
Context. The bright star $\eta $ Carinae is the most massive and luminous star in our region of the Milky Way. Though it has been extensively studied using many different techniques, its physical nature and the mechanism that led to the creation of the Homunculus nebula are still debated.
Aims. We aimed at resolving the central engine of the $\eta $ Carinae complex in the near-infrared on angular scales of a few milliarcseconds.
Methods. We used the VINCI instrument of the VLTI to recombine coherently the light from two telescopes in the K band.
Results. We report a total of 142 visibility measurements of $\eta $ Car, part of which were analyzed by Van Boekel et al. (2003, A&A, 410, L37). These observations were carried out on projected baselines ranging from 8 to 112 m in length, using either two 0.35 m siderostats or two 8-m Unit Telescopes. These observations cover the November 2001-January 2004 period.
Conclusions. The reported visibility data are in satisfactory agreement with the recent results obtained with AMBER/VLTI by Weigelt et al. (2006), asuming that the flux of $\eta $ Car encircled within 70 mas reaches 56% of the total flux within 1400 mas, in the K band. We also confirm that the squared visibility curve of $\eta $ Car as a function of spatial frequency follows closely an exponential model.

Key words: stars: individual: $\eta $ Carinae - stars: circumstellar matter - technique: interferometric - stars: early-type

1 Introduction

$\eta $ Carinae, the brightest example of the S Doradus class of stars, is the most massive, most luminous star in our region of the Milky Way. Over the last two hundred years $\eta $ Car has shown many signs of violent activity, with in particular a spectacular eruption in the 1840s that created the Homunculus nebula. The study of $\eta $ Car raises important questions about how the most massive stars may end their lives. The central object was studied by Weigelt & Ebersberger (1986) and Falcke et al. (1996) using speckle interferometry at an angular resolution of the order of 30 milliarcsec (mas). This revealed a complex structure with several equatorial blobs at distances of 0.1 to 2 arcsec from the star, but the central engine remained unresolved. Long baseline interferometry, currently the only technique allowing the mas resolution necessary to resolve $\eta $ Car, was recently applied to this star in the near- and mid-infrared domains by Van Boekel et al. (2003), Chesneau et al. (2005) and Weigelt et al. (2007). At the estimated distance of $\eta $ Car of 2.3 kpc (Davidson & Humphreys 1997; Davidson et al. 2001; Smith 2006), one mas corresponds to 2.3 AU. We report in this Research Note the complete corpus of VINCI observations of $\eta $ Car in the K band, including those discussed by Van Boekel et al. (2003).

  
2 Observations

The Very Large Telescope Interferometer (VLTI, Glindemann et al. 2003) has been operated by the European Southern Observatory on top of the Cerro Paranal, in Northern Chile since March 2001. For the present work, the light from $\eta $ Car and its calibrators was collected either by two 0.35 m VLTI Test Siderostats or two 8 m Unit Telescopes (UTs) without adaptive optics. It was subsequently recombined coherently in the VINCI instrument using a K band filter ( $\lambda=2.0{-}2.4~\mu$m).

We have observed $\eta $ Car repeatedly over the period November 2001 to January 2004. This resulted in a total of 71 000 interferograms on this target, out of which 50% (35 639) were selected automatically by the pipeline. Approximately the same quantity of data were obtained on the calibrators. We used the standard VINCI data reduction pipeline (Kervella et al. 2004, version 3.1) to derive instrumental visibilities. The calibration of $\eta $ Car's visibilities was done using well-known reference stars selected in the Bordé et al. (2002) and Cohen et al. (1999) catalogues, except $\beta$ Car. The diameter of $\beta$ Car was computed from an interferometric measurement obtained with the Intensity Interferometer (Hanbury Brown et al. 1974). The original V band uniform disk (UD) angular diameter was converted into a K band uniform disk angular diameter ( $\theta_{\rm UD} = 1.54 \pm 0.10$ mas) using linear limb darkening coefficients from Claret et al. (2000). Thanks to the relatively low values of $\eta $ Car's visibilities, the systematic uncertainty due to the calibrators is in general a small fraction of the total error bars.

The calibrated visibility values obtained on $\eta $ Car are listed in Table 1. Thanks to the use of several different telescope configurations and to the supersynthesis effect, we were able to cover a broad range of baseline lengths and azimuth. The (u,v) coverage of our observations is presented in Fig. 1.


  \begin{figure}
\par\includegraphics[width=8cm,clip]{aa6554f1.eps}
\end{figure} Figure 1: (u,v) coverage of the $\eta $ Car observations. Large spots represent the UT observations and small spots the siderostat observations (North is up and East is to the right).

   
3 Effective wavelength

The VINCI instrument has no spectral resolution and its bandpass corresponds to the K band filter (2.0-2.4 $\mu$m). It is thus important to compute the precise effective wavelength of the instrument in order to determine the spatial frequency of the observation. The true effective wavelength differs from the filter mean wavelength mainly because of the object spectrum shape, the detector quantum efficiency, and the fiber beam combiner transmission. To derive the effective wavelength of our observations, we computed a model taking into account $\eta $ Car's spectrum. The instrumental transmission of VINCI and the VLTI was measured on bright reference stars with the UTs (see Kervella et al. 2003, for details). Due to the extraordinarily dense, opaque stellar wind, the shape of the $\eta $ Car spectrum in the infrared is different from the curve of a black body at the effective temperature of the central object. In particular, the flux is increasing by about 20% from 2.0 to 2.5 $\mu$m (Smith 2002). In our model, no spectral line either in emission or absorption has been taken into account, considering the relatively limited contribution of these spectral features to the total flux in the K band. Taking the average wavelength of this model spectrum gives an effective wavelength of $\lambda_{{\rm eff}} = 2.196~\mu$m for our $\eta $ Car observations, slightly longer than the typical 2.179 $\mu$m value for solar-type stars. We estimate the uncertainty on this effective wavelength to less than $\pm$0.5%, or $\pm$$0.01~\mu$m.

  
4 Interferometric field of view

When injecting the light from an extended astronomical object into a single-mode fiber, the wavefront corrugation by the atmosphere (loss of coherence) is converted into photometric fluctuations. They are easily corrected during the data processing using the dedicated photometric channels of VINCI. Unfortunately, the restoration of coherence by spatial filtering comes at the expense of a very small field of view (FOV). It is well approximated by the diffraction pattern of a telescope whose size is the geometric mean of the apertures of the two telescopes. In the case of our homogeneous two-UT observations, the FOV is thus 70 mas in the K band. Considering the extension of the $\eta $ Car complex, this limited FOV has an impact on the measured visibilities.

Guyon (2002) studied in detail this limitation for the interferometric observation of extended objects. One important conclusion is that the effective FOV depends on the seeing, and so does the visibility. This is particularly true when large telescopes are used without adaptive optics, as this was the case for our observations. While all the UTs are now equipped with MACAO adaptive optics systems (Arsenault et al. 2004), the early observations reported here were all obtained with atmosphere limited point spread functions. The atmospheric turbulence creates a large cloud of speckles on the fiber head, and incoherent light coming from separate parts of the object is coupled into the fiber, therefore reducing the contrast of the fringes. As a second order effect, different local seeing conditions for the two UTs could also slightly degrade the visibilities. In the case of small objects such as single stars, this effect is negligible, but $\eta $ Car is surrounded by a large and bright envelope that is resolved by the UTs and contributes significantly to the light distribution within the FOV.

Practically, this means that the visibility measurements obtained with the UTs should be debiased from the seeing fluctuations. Unfortunately, this is not an easy task because the relationship between the speckle cloud size (defined by the seeing) and the flux coupled into the optical fiber is unknown. Tentatively, we mention as a first estimation of the UTs FOV the observatory seeing in the K band at the time of the observations. The seeing values from the Paranal DIMM, obtained at $\lambda = 0.5~\mu$m have been converted to the K band assuming a classical $\lambda^{-6/5}$ dependance. Future comparisons of the visibility measurements reported in the present Note with results from other instruments should take into account their relative interferometric FOV.

On the other hand, the observations obtained with the 0.35 m siderostats are in principle not affected by this bias because most of the $\eta $ Car flux is coming from an area on the sky that is contained into the Airy pattern of these telescopes. Therefore, the obtained visibility is expected to be a faithful measurement of $\eta $ Car's intrinsic visibility in the 1.40 arcsec FOV of the siderostats. For the E0-G1 baseline, many visibility points have been obtained on different nights, with a broad range of seeing conditions. The fact that they give very consistent visibility values is a confirmation that the FOV variation is negligible for the siderostats.

5 Discussion

Figure 2 shows a comparison of the VINCI squared visibilities with the AMBER model fitting result of Weigelt et al. (2007), represented as a thick curve. The VINCI squared visibilities show a strong decrease with increasing spatial frequencies, clearly indicating that the central source is resolved by the interferometer. The measurements obtained with the UTs, though in principle affected by an uncertainty due to the variation of the FOV with the seeing, are roughly consistent with the siderostat data obtained on comparable baselines. The simple model developed by Hillier et al. (2001, 2006), was adjusted by Weigelt et al. (2007) to the AMBER observations of $\eta $ Car in the continuum at $\lambda=2.174~\mu$m. This model is well reproduced by an exponential curve following the expression:

\begin{displaymath}V^2 = 1.008~\exp~(-0.016\ s),
\end{displaymath} (1)

where $s=B/\lambda$ is the spatial frequency. Our wavelength reference is $\lambda=2.196~\mu$m (Sect. 3). On the same figure, the dashed curve is an exponential fit to the VINCI data:

\begin{displaymath}V^2 = 0.322~\exp~(-0.016\ s).
\end{displaymath} (2)

The slopes (in logarithmic scale) of the VINCI data fit and the model representing the AMBER measurements are in excellent agreement. However, the ratio of the two (VINCI/AMBER) is $\rho^2 = 32$% in squared visibilities, translating into a factor $\rho = 56$% in visibilities. This ratio is constant with the spatial frequency, the signature of a fully resolved component.
  \begin{figure}
\par\includegraphics[width=8cm,clip]{aa6554f2.eps}\end{figure} Figure 2: Squared visibilities obtained on $\eta $ Car with VINCI, compared to the model fitting result of Weigelt et al. (2007), represented as a solid curve. The UT data points are represented with open squares.

To estimate the contribution of this extended component, we can consider the FOV of the two instruments. While the AMBER observations were obtained with the MACAO adaptive optics system in function (the FOV was thus $\approx$70 mas), the FOV of the VINCI siderostat observations was much larger, $\approx$1400 mas. From the observed ratio $\rho$ between the visibilities measured by VINCI and AMBER, we can infer that 56% of the 1400 mas encircled K band flux of $\eta $ Car comes from within the 70 mas point spread function of a single UT. This value is nicely consistent with the independent measurement by Van Boekel et al. (2003), based on adaptive optics observations with the NACOinstrument, that gives an encircled energy of 57% within 70 mas. When corrected for the contribution of the extended emission, the visibilities measured by AMBER and VINCI are in excellent agreement.

A discussion of the shape of the dense stellar wind of $\eta $ Car can be found in Smith et al. (2003) and Van Boekel et al. (2003). To improve the currently simplified spherical models, this observable appears highly desirable. The operating VLTI instruments are now routinely providing spectro-interferometric datasets on $\eta $ Car (Weigelt et al. 2007; Chesneau et al. 2005), and the planned second generation will combine at least four telescopes, allowing to obtain rich data cubes at mas scales. This is an essential effort to follow the extremely fast evolution of $\eta $ Car (Martin et al. 2006). In this context, the simple, two-telescopes, broadband VINCI data provide an interesting fiducial.

Acknowledgements
Based on observations made with ESO's VLT Interferometer at Cerro Paranal, Chile. The VINCI data were retrieved from the ESO/ST-ECF Archive. This research made use of the SIMBAD and VIZIER databases at the CDS, Strasbourg (France), and of NASA's Astrophysics Data System Bibliographic Services.

References

 

  
6 Online Material


   
Table 1: Squared visibilities measured with VINCI on $\eta $ Car. The seeing in the K band at the time of the observation is given as the FOV with the UTs (see Sect. 4). N is the number of processsed interferograms, B the baseline length, and Az. the azimuth angle of the projected baseline (North = 0$^\circ $, East = 90$^\circ $). The squared visibility values and error bars are expressed in percents. The statistical and systematic (from the calibrator star estimated angular size) error contributions are given separately.

JD $~- 2.45\times 10^6$
Stations FOV ('') N B (m) Az. ($\deg$) $V^2 \pm$ stat. $\pm$ syst. (%) Calibrators

2 216.8643
UT1-UT3 0.15 35 96.350 179.21 $ 0.50 \pm 0.04 \pm 0.01 $ $\gamma^{2}$ Vol
2 216.8666 UT1-UT3 0.15 38 96.353 179.79 $ 0.45 \pm 0.07 \pm 0.01 $ $\gamma^{2}$ Vol
2 246.8287 UT1-UT3 0.37 108 95.906 10.59 $ 1.01 \pm 0.11 \pm 0.03 $ $\gamma^{2}$ Vol. $\beta$ Car
2 246.8310 UT1-UT3 0.37 73 95.857 11.13 $ 0.85 \pm 0.18 \pm 0.02 $ $\gamma^{2}$ Vol. $\beta$ Car
2 302.8796 E0-G0 1.40 183 14.264 102.33 $ 21.19 \pm 1.98 \pm 0.05 $ HR 4630
2 302.8851 E0-G0 1.40 147 14.139 104.15 $ 19.96 \pm 2.27 \pm 0.05 $ HR 4630
2 304.8225 UT1-UT3 0.12 55 85.216 46.55 $ 2.36 \pm 0.10 \pm 0.05 $ HR 4546
2 304.8239 UT1-UT3 0.12 203 85.033 46.87 $ 2.00 \pm 0.06 \pm 0.04 $ HR 4546
2 451.5692 E0-G1 1.40 83 62.115 6.82 $ 2.22 \pm 0.29 \pm 0.07 $ $\theta$ Cen
2 452.5393 E0-G1 1.40 29 62.229 0.10 $ 2.73 \pm 0.33 \pm 0.07 $ HR 4050
2 452.5426 E0-G1 1.40 142 62.227 0.90 $ 2.87 \pm 0.35 \pm 0.08 $ HR 4050
2 452.5504 E0-G1 1.40 253 62.209 2.84 $ 2.32 \pm 0.11 \pm 0.06 $ HR 4050
2 453.5382 E0-G1 1.40 30 62.228 0.49 $ 2.45 \pm 0.58 \pm 0.07 $ HR 4050
2 453.5480 E0-G1 1.40 224 62.207 2.93 $ 2.54 \pm 0.12 \pm 0.08 $ HR 4050
2 453.5521 E0-G1 1.40 113 62.190 3.93 $ 2.54 \pm 0.31 \pm 0.08 $ HR 4050
2 675.8452 B3-D1 1.40 139 21.815 97.97 $ 12.89 \pm 1.15 \pm 0.04 $ HR 4050
2 675.8537 B3-D1 1.40 221 21.540 100.74 $ 13.11 \pm 0.63 \pm 0.04 $ HR 4050
2 675.8599 B3-D1 1.40 111 21.331 102.80 $ 12.36 \pm 1.19 \pm 0.04 $ HR 4050
2 675.9027 B3-D1 1.40 237 19.763 117.77 $ 12.09 \pm 0.60 \pm 0.03 $ HR 4050
2 675.9095 B3-D1 1.40 108 19.501 120.31 $ 12.67 \pm 1.56 \pm 0.03 $ HR 4050
2 624.7905 B3-C3 1.40 466 7.932 37.64 $ 26.38 \pm 1.15 \pm 0.01 $ HR 4050
2 624.7948 B3-C3 1.40 373 7.940 39.05 $ 24.84 \pm 1.18 \pm 0.01 $ HR 4050
2 624.7988 B3-C3 1.40 390 7.947 40.37 $ 24.35 \pm 1.15 \pm 0.01 $ HR 4050
2 624.8400 B3-C3 1.40 144 7.986 53.48 $ 25.79 \pm 1.94 \pm 0.01 $ HR 4050
2 624.8581 B3-C3 1.40 356 7.978 59.09 $ 25.61 \pm 1.13 \pm 0.01 $ HR 4050
2 626.7952 B3-C3 1.40 333 7.950 40.99 $ 22.91 \pm 0.95 \pm 0.01 $ HR 4050
2 626.8014 B3-C3 1.40 337 7.959 42.97 $ 23.34 \pm 0.88 \pm 0.01 $ HR 4050
2 626.8141 B3-C3 1.40 349 7.974 47.06 $ 23.31 \pm 0.78 \pm 0.01 $ HR 4050
2 626.8453 B3-C3 1.40 468 7.983 56.82 $ 25.40 \pm 0.68 \pm 0.01 $ HR 4050
2 626.8496 B3-C3 1.40 421 7.981 58.15 $ 26.07 \pm 0.78 \pm 0.01 $ HR 4050
2 626.8539 B3-C3 1.40 381 7.977 59.49 $ 25.79 \pm 0.85 \pm 0.01 $ HR 4050
2 627.8450 B3-C3 1.40 235 7.982 57.58 $ 24.50 \pm 1.88 \pm 0.01 $ HR 4050
2 627.8496 B3-C3 1.40 283 7.978 58.99 $ 25.06 \pm 1.68 \pm 0.01 $ HR 4050
2 627.8539 B3-C3 1.40 313 7.974 60.32 $ 25.28 \pm 1.41 \pm 0.01 $ HR 4050
2 628.8599 B3-C3 1.40 277 7.960 62.97 $ 24.13 \pm 1.30 \pm 0.01 $ HR 4050
2 628.8650 B3-C3 1.40 147 7.950 64.53 $ 26.82 \pm 2.33 \pm 0.01 $ HR 4050
2 630.8258 B3-C3 1.40 139 7.986 54.17 $ 24.57 \pm 2.53 \pm 0.01 $ HR 4050
2 630.8601 B3-C3 1.40 372 7.949 64.71 $ 23.47 \pm 0.98 \pm 0.01 $ HR 4050
2 631.8387 B3-C3 1.40 205 7.978 59.00 $ 24.13 \pm 1.14 \pm 0.01 $ HR 4050
2 631.8428 B3-C3 1.40 90 7.974 60.25 $ 24.40 \pm 2.75 \pm 0.01 $ HR 4050
2 631.8780 B3-C3 1.40 151 7.888 70.97 $ 24.46 \pm 1.10 \pm 0.01 $ HR 4050
2 651.8286 B3-C3 1.40 435 7.867 72.53 $ 27.06 \pm 1.01 \pm 0.01 $ HR 4050
2 651.8534 B3-C3 1.40 195 7.740 80.02 $ 25.86 \pm 1.93 \pm 0.01 $ HR 4050
2 651.8619 B3-C3 1.40 421 7.684 82.62 $ 25.79 \pm 1.09 \pm 0.01 $ HR 4050
2 651.8702 B3-C3 1.40 332 7.625 85.15 $ 24.29 \pm 1.13 \pm 0.01 $ HR 4050
2 652.8461 B3-C3 1.40 185 7.767 78.64 $ 28.03 \pm 1.38 \pm 0.01 $ HR 4050
2 652.8640 B3-C3 1.40 142 7.650 84.11 $ 26.78 \pm 2.61 \pm 0.01 $ HR 4050
2 654.7670 B3-C3 1.40 88 7.984 56.25 $ 24.93 \pm 0.98 \pm 0.01 $ HR 4050
2 654.7718 B3-C3 1.40 272 7.982 57.73 $ 23.59 \pm 0.79 \pm 0.01 $ HR 4050
2 654.7769 B3-C3 1.40 120 7.977 59.31 $ 28.27 \pm 2.99 \pm 0.01 $ HR 4050
2 654.8272 B3-C3 1.40 71 7.837 74.59 $ 26.90 \pm 1.44 \pm 0.01 $ HR 4050
2 654.8311 B3-C3 1.40 335 7.818 75.77 $ 24.46 \pm 0.83 \pm 0.01 $ HR 4050
2 654.8483 B3-C3 1.40 435 7.720 80.99 $ 26.62 \pm 0.57 \pm 0.01 $ HR 4050
2 663.7817 B3-D1 1.40 212 23.795 68.34 $ 15.19 \pm 0.91 \pm 0.05 $ HR 4050
2 664.8213 B3-D1 1.40 66 23.197 81.14 $ 12.54 \pm 1.77 \pm 0.04 $ HR 4050
2 664.8519 B3-D1 1.40 187 22.493 90.57 $ 14.36 \pm 1.33 \pm 0.05 $ HR 4050
2 664.8561 B3-D1 1.40 187 22.379 91.88 $ 14.41 \pm 1.23 \pm 0.05 $ HR 4050
2 665.8654 B3-D1 1.40 227 22.032 95.70 $ 12.34 \pm 0.80 \pm 0.04 $ HR 4050
2 670.6898 B3-D1 1.40 320 23.946 45.81 $ 13.89 \pm 0.72 \pm 0.05 $ HR 4050
2 670.7270 B3-D1 1.40 263 23.985 57.49 $ 16.20 \pm 1.43 \pm 0.06 $ HR 4050
2 670.7312 B3-D1 1.40 287 23.976 58.77 $ 14.12 \pm 1.24 \pm 0.05 $ HR 4050
2 670.7567 B3-D1 1.40 217 23.845 66.57 $ 16.16 \pm 1.34 \pm 0.06 $ HR 4050
2 670.7661 B3-D1 1.40 177 23.762 69.40 $ 15.69 \pm 1.75 \pm 0.05 $ HR 4050
2 670.8071 B3-D1 1.40 172 23.154 81.81 $ 13.67 \pm 1.46 \pm 0.04 $ HR 4050
2 670.8121 B3-D1 1.40 158 23.051 83.35 $ 14.16 \pm 1.12 \pm 0.05 $ HR 4050
2 675.8452 B3-D1 1.40 139 21.815 97.97 $ 12.89 \pm 1.15 \pm 0.04 $ HR 4050
2 675.8537 B3-D1 1.40 221 21.540 100.74 $ 13.11 \pm 0.63 \pm 0.04 $ HR 4050
2 675.8599 B3-D1 1.40 111 21.331 102.80 $ 12.36 \pm 1.19 \pm 0.04 $ HR 4050
2 675.9027 B3-D1 1.40 237 19.763 117.77 $ 12.09 \pm 0.60 \pm 0.03 $ HR 4050
2 675.9095 B3-D1 1.40 108 19.501 120.31 $ 12.67 \pm 1.56 \pm 0.03 $ HR 4050
2 677.7022 B3-D1 1.40 458 23.993 55.70 $ 14.67 \pm 0.45 \pm 0.05 $ HR 4050
2 677.7094 B3-D1 1.40 466 23.982 57.94 $ 14.56 \pm 0.42 \pm 0.05 $ HR 4050
2 677.7168 B3-D1 1.40 463 23.961 60.21 $ 13.88 \pm 0.41 \pm 0.05 $ HR 4050
2 677.7542 B3-D1 1.40 389 23.684 71.59 $ 12.47 \pm 0.40 \pm 0.04 $ HR 4050
2 677.7617 B3-D1 1.40 357 23.590 73.85 $ 12.07 \pm 0.43 \pm 0.04 $ HR 4050
2 677.7698 B3-D1 1.40 377 23.473 76.31 $ 12.32 \pm 0.41 \pm 0.04 $ HR 4050
2 678.8376 B3-D1 1.40 485 21.795 98.17 $ 13.91 \pm 0.32 \pm 0.04 $ HR 4050
2 678.8447 B3-D1 1.40 450 21.565 100.49 $ 13.19 \pm 0.32 \pm 0.04 $ HR 4050
2 678.8519 B3-D1 1.40 386 21.326 102.85 $ 12.32 \pm 0.35 \pm 0.04 $ HR 4050
2 678.8914 B3-D1 1.40 389 19.881 116.62 $ 14.84 \pm 0.40 \pm 0.04 $ HR 4050
2 678.8979 B3-D1 1.40 208 19.634 119.02 $ 15.38 \pm 0.60 \pm 0.04 $ HR 4050
2 679.8071 B3-D1 1.40 387 22.594 89.36 $ 13.53 \pm 0.32 \pm 0.04 $ HR 4050
2 679.8149 B3-D1 1.40 256 22.386 91.81 $ 12.34 \pm 0.38 \pm 0.04 $ HR 4050
2 679.8216 B3-D1 1.40 285 22.197 93.92 $ 12.87 \pm 0.52 \pm 0.04 $ HR 4050
2 679.8580 B3-D1 1.40 355 21.018 105.82 $ 13.10 \pm 0.39 \pm 0.04 $ HR 4050
2 679.8644 B3-D1 1.40 113 20.789 108.00 $ 13.88 \pm 2.00 \pm 0.04 $ HR 4050
2 679.8941 B3-D1 1.40 193 19.674 118.63 $ 15.15 \pm 0.90 \pm 0.04 $ HR 4050
2 683.7023 B3-D1 1.40 206 23.954 60.78 $ 11.48 \pm 0.86 \pm 0.03 $ HR 4050
2 683.7105 B3-D1 1.40 128 23.916 63.31 $ 13.09 \pm 1.79 \pm 0.03 $ HR 4050
2 683.7171 B3-D1 1.40 169 23.875 65.31 $ 12.65 \pm 1.20 \pm 0.03 $ HR 4050
2 683.7274 B3-D1 1.40 430 23.792 68.45 $ 12.83 \pm 0.46 \pm 0.03 $ HR 4050
2 683.7347 B3-D1 1.40 408 23.719 70.63 $ 12.55 \pm 0.49 \pm 0.03 $ HR 4050
2 683.7421 B3-D1 1.40 437 23.631 72.89 $ 13.48 \pm 0.48 \pm 0.03 $ HR 4050
2 683.7746 B3-D1 1.40 431 23.094 82.72 $ 12.31 \pm 0.43 \pm 0.03 $ HR 4050
2 683.7819 B3-D1 1.40 467 22.936 84.96 $ 13.01 \pm 0.44 \pm 0.03 $ HR 4050
2 683.7888 B3-D1 1.40 444 22.775 87.10 $ 12.72 \pm 0.45 \pm 0.03 $ HR 4050
2 683.8185 B3-D1 1.40 243 21.963 96.43 $ 12.14 \pm 0.50 \pm 0.03 $ HR 4050
2 683.8254 B3-D1 1.40 105 21.749 98.64 $ 13.00 \pm 1.64 \pm 0.03 $ HR 4050
2 683.8581 B3-D1 1.40 192 20.621 109.59 $ 12.09 \pm 0.64 \pm 0.03 $ HR 4050
2 683.8658 B3-D1 1.40 449 20.334 112.31 $ 13.39 \pm 0.46 \pm 0.03 $ HR 4050
2 683.8736 B3-D1 1.40 256 20.040 115.10 $ 12.48 \pm 0.93 \pm 0.03 $ HR 4050
2 683.8928 B3-D1 1.40 172 19.306 122.25 $ 14.13 \pm 1.31 \pm 0.04 $ HR 4050
2 683.9008 B3-D1 1.40 272 18.998 125.39 $ 13.21 \pm 0.83 \pm 0.03 $ HR 4050
2 683.9065 B3-D1 1.40 275 18.784 127.63 $ 13.83 \pm 0.75 \pm 0.04 $ HR 4050
2 684.7819 B3-D1 1.40 211 22.874 85.81 $ 13.05 \pm 0.59 \pm 0.01 $ HR 4050
2 684.7929 B3-D1 1.40 80 22.607 89.21 $ 11.33 \pm 1.71 \pm 0.01 $ HR 4050
2 684.7992 B3-D1 1.40 118 22.442 91.16 $ 12.58 \pm 1.44 \pm 0.01 $ HR 4050
2 684.8310 B3-D1 1.40 198 21.476 101.38 $ 12.17 \pm 0.49 \pm 0.01 $ HR 4050
2 741.7918 B3-M0 1.40 55 84.580 131.47 $ 1.12 \pm 0.37 \pm 0.04 $ HR 4526
2 742.7684 B3-M0 1.40 70 90.319 122.20 $ 0.80 \pm 0.23 \pm 0.03 $ HR 4526
2 742.7849 B3-M0 1.40 52 85.714 129.50 $ 2.52 \pm 1.12 \pm 0.09 $ HR 4526
2 745.6829 B3-M0 1.40 36 112.435 93.90 $ 0.68 \pm 0.71 \pm 0.01 $ HR 4831
2 769.6173 B3-M0 1.40 104 112.447 93.89 $ 0.81 \pm 0.12 \pm 0.01 $ HR 4831
2 769.6249 B3-M0 1.40 94 110.408 96.36 $ 0.65 \pm 0.13 \pm 0.01 $ HR 4831
2 769.6299 B3-M0 1.40 111 109.049 98.01 $ 0.82 \pm 0.12 \pm 0.01 $ HR 4831
2 770.6169 B3-M0 1.40 82 111.816 94.66 $ 0.85 \pm 0.21 \pm 0.01 $ HR 4831
2 770.6224 B3-M0 1.40 64 110.358 96.42 $ 0.94 \pm 0.33 \pm 0.01 $ HR 4831
2 770.6280 B3-M0 1.40 81 108.811 98.29 $ 0.63 \pm 0.19 \pm 0.01 $ HR 4831
2 786.6480 B3-M0 1.40 226 90.383 122.10 $ 1.47 \pm 0.08 \pm 0.05 $ HR 4546
2 786.6581 B3-M0 1.40 184 87.543 126.48 $ 1.50 \pm 0.10 \pm 0.05 $ HR 4546
2 786.6634 B3-M0 1.40 133 86.084 128.87 $ 1.49 \pm 0.13 \pm 0.05 $ HR 4546
2 790.5635 E0-G0 1.40 480 13.813 108.79 $ 25.20 \pm 0.39 \pm 0.01 $ HR 4546
2 790.5686 E0-G0 1.40 369 13.688 110.56 $ 21.89 \pm 0.40 \pm 0.01 $ HR 4546
2 790.5733 E0-G0 1.40 346 13.571 112.23 $ 23.13 \pm 0.47 \pm 0.01 $ HR 4546
2 790.6054 E0-G0 1.40 426 12.755 124.14 $ 26.06 \pm 0.59 \pm 0.01 $ HR 4546
2 790.6103 E0-G0 1.40 479 12.633 126.03 $ 28.03 \pm 0.58 \pm 0.01 $ HR 4546
2 790.6151 E0-G0 1.40 406 12.512 127.94 $ 24.87 \pm 0.56 \pm 0.01 $ HR 4546
2 791.4925 E0-G0 1.40 468 15.214 86.68 $ 25.02 \pm 0.30 \pm 0.01 $ HR 4546
2 791.4974 E0-G0 1.40 358 15.135 88.20 $ 22.31 \pm 0.36 \pm 0.01 $ HR 4546
2 791.5023 E0-G0 1.40 180 15.053 89.70 $ 22.05 \pm 0.85 \pm 0.01 $ HR 4546
2 791.5296 E0-G0 1.40 419 14.526 98.37 $ 23.30 \pm 0.35 \pm 0.01 $ HR 4546
2 791.5347 E0-G0 1.40 297 14.416 100.03 $ 21.75 \pm 0.45 \pm 0.01 $ HR 4546
2 791.5398 E0-G0 1.40 154 14.305 101.69 $ 20.42 \pm 0.96 \pm 0.01 $ HR 4546
2 791.5737 E0-G0 1.40 445 13.494 113.32 $ 25.73 \pm 0.59 \pm 0.01 $ HR 4546
2 791.5786 E0-G0 1.40 381 13.371 115.08 $ 24.49 \pm 0.59 \pm 0.01 $ HR 4546
2 791.5840 E0-G0 1.40 329 13.233 117.06 $ 20.99 \pm 0.58 \pm 0.01 $ HR 4546
2 791.6264 E0-G0 1.40 453 12.166 133.73 $ 25.88 \pm 0.58 \pm 0.01 $ HR 4546
2 791.6316 E0-G0 1.40 375 12.044 135.90 $ 25.05 \pm 0.61 \pm 0.01 $ HR 4546
2 791.6367 E0-G0 1.40 358 11.927 138.09 $ 23.81 \pm 0.58 \pm 0.01 $ HR 4546
2 977.8452 E0-G0 1.40 390 15.962 44.66 $ 24.45 \pm 0.41 \pm 0.01 $ HR 4546
2 977.8530 E0-G0 1.40 333 15.980 47.14 $ 24.03 \pm 0.41 \pm 0.01 $ HR 4546
3 011.7317 D0-H0 1.40 111 63.563 37.94 $ 4.72 \pm 0.37 \pm 0.07 $ HR 4050



Copyright ESO 2007