(cba:news) V Sagittae, etc.

Joe Patterson jop at astro.columbia.edu
Wed Aug 13 08:06:00 EDT 1997


Dear CBAers,

Here are some of the fruits of the V Sge analysis so far.  The first file is
the mean orbital light curve during July 9-August 9, based on 130 hr of
data.  (Mags are negative, sorry.)  A simultaneous photoelectric observation
by Sergei Shugarov enabled me to assign it a well-calibrated V magnitude.

 .01          -12.84752 
 .02          -12.85892 
 .03          -12.79166 
 .04          -12.698 
 .05          -12.67278 
 .06          -12.57756 
 .07          -12.53597 
 .08          -12.49992 
 9.000001E-02               -12.42669 
 .1           -12.3738 
 .11          -12.34296 
 .12          -12.29637 
 .13          -12.25594 
 .14          -12.22873 
 .15          -12.20153 
 .16          -12.1719 
 .17          -12.14865 
 .18          -12.1565 
 .19          -12.15904 
 .2           -12.1294 
 .21          -12.09403 
 .22          -12.07776 
 .23          -12.0684 
 .24          -12.06433 
 .25          -12.06311 
 .26          -12.06076 
 .27          -12.05768 
 .28          -12.05356 
 .29          -12.071 
 .3           -12.0717 
 .31          -12.07374 
 .32          -12.08548 
 .33          -12.08468 
 .34          -12.08141 
 .35          -12.0973 
 .36          -12.10641 
 .37          -12.08429 
 .38          -12.10437 
 .39          -12.0915 
 .4           -12.09669 
 .41          -12.10396 
 .42          -12.09679 
 .43          -12.11751 
 .44          -12.15803 
 .45          -12.16208 
 .46          -12.15899 
 .47          -12.17398 
 .48          -12.18122 
 .49          -12.18056 
 .5           -12.22812 
 .51          -12.22102 
 .52          -12.23679 
 .53          -12.21054 
 .54          -12.21935 
 .55          -12.19748 
 .56          -12.18547 
 .57          -12.13879 
 .58          -12.13414 
 .59          -12.11797 
 .6           -12.10453 
 .61          -12.07228 
 .62          -12.05936 
 .63          -12.02483 
 .64          -12.03421 
 .65          -11.99236 
 .66          -12.00666 
 .67          -11.99506 
 .68          -11.99032 
 .69          -11.9824 
 .7           -11.97503 
 .71          -11.97011 
 .72          -11.97238 
 .73          -11.97023 
 .74          -11.99159 
 .75          -11.99918 
 .76          -12.0157 
 .77          -12.01053 
 .78          -12.04409 
 .79          -12.03041 
 .8           -12.06578 
 .81          -12.06788 
 .82          -12.08682 
 .83          -12.11416 
 .84          -12.14154 
 .85          -12.19025 
 .86          -12.22837 
 .87          -12.24877 
 .88          -12.25344 
 .89          -12.35721 
 .9           -12.40799 
 .91          -12.43219 
 .92          -12.45887 
 .93          -12.51216 
 .94          -12.56027 
 .95          -12.63045 
 .96          -12.65116 
 .97          -12.72338 
 .98          -12.86577 
 .99          -12.85624 
 1            -12.86464 
 1.01         -12.84752 
 1.02         -12.85892 
 1.03         -12.79166 
 1.04         -12.698 
 1.05         -12.67278 
 1.06         -12.57756 
 1.07         -12.53597 
 1.08         -12.49992 
 1.09         -12.42669 
 1.1          -12.3738 
 1.11         -12.34296 
 1.12         -12.29637 
 1.13         -12.25594 
 1.14         -12.22873 
 1.15         -12.20153 
 1.16         -12.1719 
 1.17         -12.14865 
 1.18         -12.1565 
 1.19         -12.15904 
 1.2          -12.1294 
 1.21         -12.09403 
 1.22         -12.07776 
 1.23         -12.0684 
 1.24         -12.06433 
 1.25         -12.06311 
 1.26         -12.06076 
 1.27         -12.05768 
 1.28         -12.05356 
 1.29         -12.071 
 1.3          -12.0717 
 1.31         -12.07374 
 1.32         -12.08548 
 1.33         -12.08468 
 1.34         -12.08141 
 1.35         -12.0973 
 1.36         -12.10641 
 1.37         -12.08429 
 1.38         -12.10437 
 1.39         -12.0915 
 1.4          -12.09669 
 1.41         -12.10396 
 1.42         -12.09679 
 1.43         -12.11751 
 1.44         -12.15803 
 1.45         -12.16208 
 1.46         -12.15899 
 1.47         -12.17398 
 1.48         -12.18122 
 1.49         -12.18056 
 1.5          -12.22812 
 1.51         -12.22102 
 1.52         -12.23679 
 1.53         -12.21054 
 1.54         -12.21935 
 1.55         -12.19748 
 1.56         -12.18547 
 1.57         -12.13879 
 1.58         -12.13414 
 1.59         -12.11797 
 1.6          -12.10453 
 1.61         -12.07228 
 1.62         -12.05936 
 1.63         -12.02483 
 1.64         -12.03421 
 1.65         -11.99236 
 1.66         -12.00666 
 1.67         -11.99506 
 1.68         -11.99032 
 1.69         -11.9824 
 1.7          -11.97503 
 1.71         -11.97011 
 1.72         -11.97238 
 1.73         -11.97023 
 1.74         -11.99159 
 1.75         -11.99918 
 1.76         -12.0157 
 1.77         -12.01053 
 1.78         -12.04409 
 1.79         -12.03041 
 1.8          -12.06578 
 1.81         -12.06788 
 1.82         -12.08682 
 1.83         -12.11416 
 1.84         -12.14154 
 1.85         -12.19025 
 1.86         -12.22837 
 1.87         -12.24877 
 1.88         -12.25344 
 1.89         -12.35721 
 1.9          -12.40799 
 1.91         -12.43219 
 1.92         -12.45887 
 1.93         -12.51216 
 1.94         -12.56027 
 1.95         -12.63045 
 1.96         -12.65116 
 1.97         -12.72338 
 1.98         -12.86577 
 1.99         -12.85624 
 2            -12.86464 

The second file is the O-C analysis of the primary minima, going back some
40 years.  You'll see a pretty good parabola, indicative of Porb decreasing
on a timescale of about 5 million years.  Nice behavior for a roaring
luminous star like this one (I estimate Lbol around 10**37 erg/s).

-10662   -0.076
-9696    -0.060
-8659    -0.050
-7687    -0.044
-3500    -0.030
0        -0.0006
21        0.0076
23       -0.0066
27       -0.0003
93       -0.0098
95       -0.0006
126       0.0016
159       0.0087
636       0.0100
668       0.003
764      -0.0105
797       0.0023
2856      0.0044
2860      0.0115
2889      0.0069
2891      0.0126
3652      0.0165
4117      0.0074
4966      0.010
4968      0.023
4970      0.016
4972      0.018
5104      0.014
5106      0.017
5137      0.015
5668      0.014
5672      0.024
5676      0.027
5734      0.034
5769      0.017
5773      0.025
5775      0.013
7952      0.0155
9103      0.027
9107      0.019
10826     0.0043
10828     0.0240
11220     0.0110
11221     0.0130
11222     0.0170
14788     0.0001
14790    -0.0040
14792    -0.0030
19197    -0.0142
22094    -0.0170
22100    -0.0193
22777    -0.0238
22779    -0.0329
24130    -0.0178
24132    -0.0337
24815    -0.033
24817    -0.025


Alon Retter reminds me that we still owe loyalty to V1974 Cyg.  This is true.
And he's doing a campaign on it right now and getting good results from
Israel and Japan.  So I think it's very desirable that we norteamericanos
chip in with a decent contribution from our longitude.  The star's about
15.9 now and I imagine the amplitude's still just a few percent, that's why
I had not planned to promote this.  But I believe that the larger scopes in
our network can do it, and with data from other longitudes you don't have
to count on being able to see the modulation in your data.  Dave Harvey
and Cap'n Bob take note.  Alon, keep the progress reports up (but send to
cba-news at cbastro.org, as I will be e-mail-deaf as of 
tomorrow).

Meanwhile V503 Cyg and RX1940-10 and AO Psc and FO Aqr continue to pour
a flurry of photons glancing harmlessly off the Earth's water, rocks, fields,
and shuttered observatories.

                               joe



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