VV Cep continuoous monitoring during 6h session

Hello,


last night I only recorded VV Cep during 6h10 period (5h36 total exposure time). I have acquired 82 spectra (first 8 with an exposure time of 300s then all others with exposure time of 240s). Beginning of the night with a sky background around 18 due to gibbeous Moon, and over 20 at the end but some clouds coming in around 4h TL (2h UT).

I used 7 Cep (hd204770) B7V as reference star for my instrumental response - same one for all night with air mass between 1.15 and 1.05 I believe.

In ISIS, I was able to produce (through "animation" tool) a 2D spectrogram. I first took the total spectrum as the average baseline (rescaled at 1.0 between 6627-6637), and I substracted it from all my 82 individual spectra (order 34 with Halpha only; same rescaling). This produced the following spectrogram:

There seems to be some interesting features to further investigate!


Cordialement,
Olivier

P Cygni & VV Cep

Back from our Shelyak Instruments annual spectroscopy workshop at Observatory of Haute Provence with around 50 spectroscopists from all over the World! We had a really great time, in a very friendly atmosphere but also some great observing time (wetaher was not perfect but ok for such workshop) and exceptionnal talks including a course from Steve Shore!

Tonight (21-aug-2015), I opened the observatory and observed P Cygni, a Luminous Blue Variable star with very strong wind and a typical line profile called "P Cygni profile" with a blue absorption on the side of an emission line - very strong in the case of Halpha in P cygni itself.


The night was excellent with very good seeing and a sky background magnitude around 20.5 at zenith. I first focused the telescope:

I then pointed toward P Cygni and recorded several spectra:

Here is the telescope under the dome during this acquisition:

I then took spectra of a reference star (hd198183) which I reduced to get my instrumental response for that night, at that air mass:

ISIS results for wavelength calibration (23 orders of the Shelyak Instruments eShel echelle spectrograph):

Ordre #31 :   RMS = .0014   -   Nb. raies = 7
Ordre #32 :   RMS = .0151   -   Nb. raies = 10
Ordre #33 :   RMS = .0221   -   Nb. raies = 12
Ordre #34 :   RMS = .0084   -   Nb. raies = 15
Ordre #35 :   RMS = .0090   -   Nb. raies = 15
Ordre #36 :   RMS = .0069   -   Nb. raies = 16
Ordre #37 :   RMS = .0049   -   Nb. raies = 14
Ordre #38 :   RMS = .0067   -   Nb. raies = 15
Ordre #39 :   RMS = .0100   -   Nb. raies = 17
Ordre #40 :   RMS = .0082   -   Nb. raies = 15
Ordre #41 :   RMS = .0159   -   Nb. raies = 19
Ordre #42 :   RMS = .0188   -   Nb. raies = 15
Ordre #43 :   RMS = .0105   -   Nb. raies = 16
Ordre #44 :   RMS = .0112   -   Nb. raies = 17
Ordre #45 :   RMS = .0057   -   Nb. raies = 16
Ordre #46 :   RMS = .0090   -   Nb. raies = 15
Ordre #47 :   RMS = .0090   -   Nb. raies = 12
Ordre #48 :   RMS = .0061   -   Nb. raies = 14
Ordre #49 :   RMS = .0154   -   Nb. raies = 13
Ordre #50 :   RMS = .0024   -   Nb. raies = 9
Ordre #51 :   RMS = .0123   -   Nb. raies = 10
Ordre #52 :   RMS = .0176   -   Nb. raies = 12
Ordre #53 :   RMS = .0461   -   Nb. raies = 11
Résolution :
Ordre #31 :  FWHM = 4.44  -  Dispersion = .195 A/pixel  -  R = 8371.5
Ordre #32 :  FWHM = 4.97  -  Dispersion = .187 A/pixel  -  R = 7541.3
Ordre #33 :  FWHM = 4.31  -  Dispersion = .185 A/pixel  -  R = 8512.7
Ordre #34 :  FWHM = 4.01  -  Dispersion = .179 A/pixel  -  R = 9175.9
Ordre #35 :  FWHM = 3.74  -  Dispersion = .174 A/pixel  -  R = 9841.9
Ordre #36 :  FWHM = 3.47  -  Dispersion = .169 A/pixel  -  R = 10644.1
Ordre #37 :  FWHM = 3.50  -  Dispersion = .163 A/pixel  -  R = 10609.0
Ordre #38 :  FWHM = 3.31  -  Dispersion = .161 A/pixel  -  R = 11117.8
Ordre #39 :  FWHM = 3.17  -  Dispersion = .158 A/pixel  -  R = 11493.8
Ordre #40 :  FWHM = 3.42  -  Dispersion = .153 A/pixel  -  R = 10754.0
Ordre #41 :  FWHM = 3.28  -  Dispersion = .148 A/pixel  -  R = 11263.6
Ordre #42 :  FWHM = 3.39  -  Dispersion = .145 A/pixel  -  R = 10871.7
Ordre #43 :  FWHM = 3.05  -  Dispersion = .145 A/pixel  -  R = 11760.6
Ordre #44 :  FWHM = 3.19  -  Dispersion = .140 A/pixel  -  R = 11408.9
Ordre #45 :  FWHM = 3.27  -  Dispersion = .136 A/pixel  -  R = 11267.4
Ordre #46 :  FWHM = 3.36  -  Dispersion = .133 A/pixel  -  R = 10889.0
Ordre #47 :  FWHM = 3.47  -  Dispersion = .129 A/pixel  -  R = 10694.9
Ordre #48 :  FWHM = 3.43  -  Dispersion = .126 A/pixel  -  R = 10791.9
Ordre #49 :  FWHM = 4.14  -  Dispersion = .125 A/pixel  -  R = 8883.3
Ordre #50 :  FWHM = 4.37  -  Dispersion = .119 A/pixel  -  R = 8598.7
Ordre #51 :  FWHM = 4.70  -  Dispersion = .115 A/pixel  -  R = 8130.8
Ordre #52 :  FWHM = 5.18  -  Dispersion = .115 A/pixel  -  R = 7260.5
Ordre #53 :  FWHM = 5.62  -  Dispersion = .113 A/pixel  -  R = 6689.2

P Cygni profile shows very nice emission lines:

Here is a zoom around Halpha and He I 6678 neutral helium emission line:

My next target is VV Cep, a spectroscopic binary system of great interest as the hot companion surrounded by an accretion disk will be eclipsed by the red supergiant primary star in 2017-2018. This very rare (every 20.4 years) event will be an unique opportunity to "see" the primary huge chromosphere as the hot star light through it like a flash light. It will be a continuous target for my observatory hopefully in the next few years to come!

The overall spectrum shows all the molecular bands (TiO), typical for a red supergiant star (such as Betelgeuse for exemple) but it also display emission line coming from ionized region by the hot companion.

A zoom on Halpha shows a very nice double peak with the V (blue) peak higher than the R (red) one. The two peaks are split by about 130km/s. An article by Kawabata in 1981 gives 170km/s for outside eclipse separation and 120km/s during eclipse - obviously this emission line is not stable over time

Jim's visit

Jim Edlin visited my home just before the annual OHP (Observatoiry of Haute Provence) spectroscopy workshop. As the night was clear, it was a great opportunity to do some spectroscopy with the eShel (beta Lyrae, P Cygni, NGC6543 Cat's eye nebula & VV Cep) as well as to take some great night shot - thanks to Jim for all those pictures!

In the dome...

Jim in the dome

In the control room at night.

Delphinus constellation viewed through the dome slit...

Night sky above the dome

Milky way above the dome.

Equipment inside the dome

Observatory from field above

Inside the dome

eShel / Atik 460

Two major changes done yesterday: the C11 telescope has been collimated and the Atik 460ex replaced the SBIG ST1603.

The collimation was a small effort but a big gain as the stars are now round in the guiding camera. It did improve efficiency!

The camera is also an improvement as lower noise. It took long time to find the right parameters in ISIS software to reduce the data, but software helped in adjusting the camera angle. Now, in binning 2x2, the overall system is fairly efficient except poor seeing at this location but this, I can't change!

Here is a collection of images of the observatory, control room and inside the dome. And some results from last night...

 telescope C11 inside the Pulsar 2.7m dome

the eShel fiber injection unit capture the light of the stars which are "transported" to the eShel spectrograph through a 50µm optical fiber...

 the Atik titan (blue) camera is attached to the eShel fiber injection unit so we can see the field of fiew and center the star into the 50µm fiber hole

View of the telescope inside the dome with mountains behind

the spectrographe is now dehind the (red) curtain!

 the eShel spectrograph with the calibration unit (seeral calibration lamps) controled by computer

 the dome is now open

ambiance during the night, watching a video as the system guide itself (autoguiding)

copy of screen of the computer which controls everything

spectrum of a reference star; the deep absorptions are from left to right: Hgamma, Hbeta & Halpha

a symbiotic star CH Cygni (combined spectrum) with strong emissin lines

 SPLAT-VO view of individual orders of the spectrograph (before proper merging)