spectro-aras.com

Note request for spectroscopic observations of this object (current v magnitude 7.7)

Robin



> AAVSO Alert Notice 454
>
> Monitoring of CH Cyg requested for Chandra and HST observations
> March 2, 2012
>
> Dr. Margarita Karovska, Harvard-Smithsonian Center for Astrophysics,
> has requested visual and photometric observations of the symbiotic
> variable CH Cyg in preparation for and support of Chandra and HST
> observations scheduled for later in March 2012. Dr. Karovska's
> observations will be a followup investigation of the central region
> of CH Cyg and its jet that was discovered a couple of years ago.
> AAVSO observations are requested to in order to monitor the state
> of the system and correlate with the satellite observations.
>
> Visual observations and CCD/PEP observations in all bands - U
> through J and H - are requested. Daily observations now through April
> 2012 and high-speed photometry through March would be appreciated.
> CH Cyg is currently at visual magnitude 7.7.
>
> Halpha, OIII region, and optical spectroscopy are also requested.
>
> More details on the exact dates and times of the satellite
> observations will be announced when they become available, but
> daily monitoring should begin now.
>
> Coordinates: RA 19 24 33.07 Dec. +50 14 29.1 (J2000.0)
>
> Finder charts may be plotted using the AAVSO International Variable
> Star Plotter (VSP) at http://www.aavso.org/vsp.
>
> Please report observations to the AAVSO International Database as CH CYG.
>
> Many thanks for your valuable contributions to this interesting research!
>
> This AAVSO Alert Notice was compiled by Elizabeth O. Waagen.
>

Here are my tests at H alpha from last night. It is M7, so much brighter at H alpha. A straightforward target for a LHIRES with 2400 grating

Robin

Here is the O[III] region. The spectra are again very complex but repeatable except for the emission line at ~5017A which appeared to increase significantly over the 2 hours I observed it.

Wvelength calibation was done using a mixture of Ne, Ar and Xe lines from a "Filly dot" lamp. I could not identify enough faint lines to do a good calibration using the internal neon.

Robin

Attached is the O[III] spectrum with the emission lines marked (CH Cyg has an RV of -60km/s)

I have had some feedback from Margarita Karovska. To cover all the lines Margarita is interested in, we need someone with an eShel to take some spectra or perhaps even a LISA. The HST/Chandra observations are next week.

Thanks
Robin


----- Original Message -----
From: "Margarita Karovska" <karovska@head.cfa.harvard.edu>
To: "Robin Leadbeater" <robin@threehillsobservatory.co.uk>;
Sent: Tuesday, March 06, 2012 9:35 PM
Subject: Re: Alert Notice 454: Monitoring of CH Cyg


>
> Hi Robin,
> Thank you VERY MUCH!
> The spectra look very nice.
> The variability in Halpha is possible and very interesting!
>
>
> Continuing with the Halpha and [OIII] will be great.
>
>
> ***this is extra, and maybe pushing it... but
> I have a question:
>
> Can you go as low as 4363 A
> there is another [OIII] line there that we will use in the imaging for a
> ratio with the 5007 A line.
> Also,
> It will be great to have spectra around the continuum at ~5470A
> We use the image at this wavelength for continuum subtraction from the
> 5007 A image.
>
> I don't know if any of these are a possibility, but the [SII] line at
> 6731A is of interest as well as He I 5876 A
> He II 4686 A lines.
>
>
> Any of these will be wonderful to have, especially for the period of the
> HST run sometime between 3/12 and 3/19 (and if possible before and after)
>
>
> Thank you for the spectra and your kind help with this.
> It provides a context for the HST/Chandra observations and with the
> other coordinated observations may lead to unexpected results concerning
> this fascinating object.
>
> All the best,
> Margarita

Here is my last observation a 3X1200s exposure with my eshell setup (R10000). This star was relatively low at the moment of exposure, 17° but still have strong spectral features easy to spot on the yellow/red régions. It is more difficult due to absorption in the blue. I have sent the spectra, individual orders, directly to Margarita. We can extend coverage in NIR if needed.
Nice object.

That's great

Attached is my heliocentric O[III] region spectrum from the previous night (fits, mean of 3) How does it compare? Has the unidentified emission at ~5018 A changed any more?

Cheers
Robin

Robin,
i forgot to attached the zip of the entire orders. It is a good test for the filly lamp calibration method. I had did this test during del sco HeII4686 monitoring to be sure of.
I will reduce individual exposure, 3X1200s to look for 5018A variability. But not quite sure of the SNR.
Amitiés
T

It match quite well, but my spectra is more noisy than yours. No differences seen.

Very sensitive to normalisation. I don't think it moves.

Here is a good reference from Margarita for optical spectra of CH Cyg .

Burmeister and Leedjarv, 2009, A&A, 504, 171.
http://cds.aanda.org/articles/aa/pdf/20 ... 686-09.pdf

Cheers
Robin