Talk:YZ Cassiopeiae

Notes

To get details of the star system components, I downloaded and uncompressed part of Tokovinin's multiple star catalogue described here:

http://cdsarc.u-strasbg.fr/viz-bin/Cat?J/A%2bAS/124/75

The catalogue files can be obtained from: ftp://cdsarc.u-strasbg.fr/pub/cats/J/A+AS/124/75/

This is the line from catalog.dat that describes YZ Cas:

00390+7426  0 45 39.1  74 59 17   -15   -22    9.0 0.0112 HIP 3   21 Cas, YZ Cas
IDS (1900)  RAhm RAs  +DEddmmss PMras PMdec Radvel Parall Pcd n T Name
n = number components
Pcd is Parallax code: HIP - trigonometric Hipparcos

These two lines from systems.dat give the system component details:

00390+7426    1 AB  Crphm   7.50   36.000" 160  5.66 A2IV  11.25 0.96    3.66s   0.80a H 122
00390+7426   11 Aab S2,E    0.65    0.916m   0  5.73 A2IV   8.63 F2V     2.31*   1.35* SB 41,  YZ Cas
IDS (1900) Leve Com Type   logP  Sep/Axis  PA  Vmag1 SP1   Vmag2 SP2   solMa1  solMa2  Remark

logP is Logarithm (base 10) of period in days
solMa1 is Mass of the primary,
solMa2 is Mass of the secondary, each is followed by the Mass estimation code, see note (3)

Note (3): Mass codes:
         * - given in the original publication
         a - estimated from spectral type or B-V color index from Allen tables
         s - sum of masses for the sub-system(s)
         q - estimated from primary mass and mass ratio of SB2
         m - minimum secondary mass for SB1
         v - estimated from magnitude difference of a visual binary
         : - uncertain, magnitude difference assumed to be 2 mag.

From some of the above data I derived the basic information for the article.

Tokovinin's later 2002 publication J/A+A/382/118 includes radial velocity measurements for YZ Cas B, but I did not use them.

Calculations used for deriving distances:

A-B = tangent(36.1 arcseconds) * 89 Parsecs = 3 212.9 Astronomical Units
AB-C = tangent(0.000916 arcseconds) * 89 Parsecs = 0.081524 Astronomical Units (I did not use this)

-84user (talk) 19:33, 5 September 2008 (UTC)[reply]