spectro-aras.com

Hello everyone,

short update. Neither VX CrV nor V893 Cen show emission lines. VX CrV is a Mira pulsator and the spectrum was obtained close to the minimum. I suggest obtaining another spectrum around maximum (August 2022) to see if at least Balmer lines will appear and to be able to constrain the changes in the spectral type of the star. V893 Cen was also suggested to be a Mira pulsator, but no light curve is available to confirm this assumption. Optical observations of INTEGRAL did not reveal significant variability. Therefore I think it is not needed to reobserve the object, most probably it is not a symbiotic star.

The analysis of the spectrum of THA 15-31 is published in the RNAAS here: https://iopscience.iop.org/article/10.3 ... 172/ac5ea8. Although no He II lines are detected, the hot component seems to be variable. See the paper for more details.

Jaroslav

Thanks a lot Jaroslav for this research note, we will try others targets from your list (and from the south) as soon as possible.

I'm late to this particular party - hopefully there is more to come.

Here is my spectrum from V748 Cen taken last night. The Balmer lines are in emission and I've marked the Fe II lines that are clear (also the Na lines). The SNR is not great as it was taken with my new automated set up. I'll look to have another crack at this later in the season.

Pete

nice one Peter!

Some targets of this morning taken from Chile :

- V345 Nor :





- V618 Sgr :
The magnitude of this star is not the one expected and is rather close to 9-10





- V917 Sco :
Faint target around mag. V=15

A confirmatory spectrum for V618 Sgr taken last night

I measured its V mag at 9.7 so the 2Spot team where spot on with their estimate (pardon the pun).

Its a busy spectrum!

Pete

I had a look back at my last spectrum of V618 Sgr which was taken in November 2021. Here is a plot of both.

There is quite a change in continuum. Both spectra are flux calibrated so they are reasonably comparable.

The other big change is in the Ha emission.

Pete

Hello Pete,
Nice evolution in only 5 months....
A target to follow....

Peter Velez wrote:
There is quite a change in continuum. Both spectra are flux calibrated so they are reasonably comparable.

Wow! that is a big apparent change in temperature for no change in V mag. (similar flux at 5200A) How does that happen?

Cheers
Robin

Not sure Robin - hopefully not poor processing on my part!

Will have another look at it soon

Pete