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Re: Supplemental to Shawn D's IDs of Tom D's newbies...
John was kind enough to write up these stars so I have plotted a few of
them. The files are relatively small, so I hope that none of you object to
getting them.
I am suspicious that the high point of GSC 176 3218 is an airplane or some
such. At the moment I do not have an easy way to check something like
this. I picked it out originally because the trend was there without the
high point. The data is available to check, and I could find the source
image by the date/time, but I do not have a good way to pick out this star
except through tedious measurement of the image and registering it by hand
with a star atlas. There has to be a better way. (Michael, are you
listening?)
I am attaching 5 of these stars. Sorry that I do not have more
points. This is for fun. Later we will have lots of points and will try
to be serious. Well, try. ;^)
Tom Droege
At 01:01 PM 2/14/03 +0000, you wrote:
>_No forwarding of this email address to web archived lists please_
>
>
>Hi Each
>
>Some cross ID extras
>
>72.5796 9.3916 GSC 687 209
>
>An IRAS source, so LPV looks good. Probably low amplitude if bright
>enough to be a 'regular' GSC object, as a higher amplitude thing
>would be a 'lucky hit' on the survey plates, so probably SR or L, but
>rarer LPV types not entirely precluded (need lightcurves for that).
>
>Certainly 'new'
>
>88.2707 13.1170 0.2 11.4 GSC 724 155
>
>V527 Ori, type Lb (irregular LPV)
>
>ie, already known.
>
>91.5623 13.9046 0.7 11.5 DY Ori (RV Tauri type)
>
>nothing to add
>
>101.9376 1.3717 0.3 9.1 V448 Mon (EB-type)
>
>nothing to add
>
>102.7177 -1.4294 0.6 11 TX Mon
>
>IMPORTANT: This thing has been monitored by ASAS, and therefore ASAS
>Ic time series data is available online [websearch on asas and
>princeton is how i find that usually]. Although obviously not
>contemporaneous with TASS latest, comparison of Ic from both might be
>of interest re amplitude, median/mean what have you. Independent
>check. As you know, Ic data sources are rare. An object that is
>neither very red nor very blue, so no significant colour problems to
>worry about (ie transformation from BT and VT to Ic should not have
>been outside the usual range), and the variable is going to be very
>consistent in Ic, so TASS has a baseline to tally against for a
>variable lightcurve here. Cepheids are also very stable in period, so
>the TASS Ic should 'map' on to the ASAS Ic phase-wise, and any
>mismatch in magnitude comtemplated upon. Might be informative, might
>not ;)
>
>109.1269 3.4760 0.4 10.7 GSC 168 1700
>
>This thing is a quite blue star, a known Luminous Blue star, and also
>a known hydrogen alpha emission source.
>
>B-V from Tycho2 about 0. Spectral class B8 Ib-II, so a blue bright
>giant at least.
>
>This makes it fairly interesting and different from the usual run of
>the mill, therefore. It could be a bCep (beta Cepheid), or some
>variable Be star if the luminosity class is in error. ACyg (Alpha
>Cygni) type looks precluded by the amplitude you've got.
>
>However, it being very blue no doubt puts it on the edge of accepted
>colour range for the transformations used, so there are potential
>problems????
>
>_Definitely_ a candidate for follow up campaigns, both on short and
>long term terms, for those with CCDs who are interested in such.
>
>CAVEATS: remembering back to TASS IV data I've looked at before.
>Caveat 1: if the variation is intranight and less than 0.1 - 0.2 mag,
>likelihood is it is constant and variation in the data is spurious.
>Variation of 0.4 V seems to preclude that.
>
>Caveat 2: if the variation is internight, ie separate nights, still
>needs double checking, although 0.4 should be outside internight
>calibration differences' range.
>
>Finally, the thing could 'simply' be an eclipser, and all other
>exotic characters coincidental irrelevances in this case. All types
>of variables are also capable of being eclipsers really, though
>objects that are both one type of variable and an eclipser are rare-
>ish.
>
>Probably warrants a SIMBAD search, including bibliography check.
>
>Lightcurve info needed.
>
>'New' 'variable' though.
>
>110.3632 6.2743 0.9 12.4 GSC 176 3218 (blend?)
>
>The things 'orange', so it could be an eclipser of say the EW ilk,
>which'd match the amplitude. There are several quite rare more
>exotic alternatives, would need a lightcurve to tell.
>
>Low amplitude LPV not precluded either.
>
>'New', as in not in any commonly known or even on most damned obscure
>lists, up to date at beginning of 2003.
>
>116.9394 9.6885 1.2 12 GSC 783 628
>
>IRAS source, good indicator for LPV type. Known to GSC suggests
>smallish amplitude, but V = 1.2 here, probably as a lower limit too?
>Bit of a surprise for that to have been missed in the past. Is the
>variation intranight or internight or both? (Remember, with small
>samples of snapshot data, stuff is difficult, even eclipsers can
>emulate other stuff that way, and many things can be IRAS sources,
>not just LPVs). I'll check archival survey images to see if LPV fits
>as type.
>
>118.7544 0.3936 0.6 11.3 GSC 181 179
>
>An IRAS source, so probably LPV. Small standard deviations on Tycho2
>BT and VT also suggest a low amplitude one.
>
>Well, not only Mk III, Mk IV and Arne's FASTT survey have picked this
>one up, but also ASAS again.
>
>Mean ASAS Ic is 9.5, dependant on how much of the full amplitude
>range you've got, Tom, so should yours be. Again, ASAS data
>available on line, this time TASS Ic behaviour for a red star could
>be compared to Ic from elsewhere, at least in terms of mean mag and
>usual amplitude range.
>
>Given mean Tycho2 BT-VT = 1.05, and V-Ic ~ 2(B-V), then mean(V_TASS) -
> mean(Ic_ASAS) = 1.8 looks about right. Arne's mean CCD R_FASTT of
>10.4 also fits in nicely here.
>
>'New'
>
>123.3777 13.8015 1.1 11.4 SU Cnc (Mira type)
>
>Nothing to add.
>
>
>Cheers
>
>John
>
>John Greaves
GSC_176_3218.png
GSC_181_179.png
GSC_687_209.png
GSC_783_628.png
TX_Mon.png
