A variable star of type α² Hounds Dogs is a type of rotating variable stars . These are the stars of the main sequence of spectral classes B8p-A7p. They have strong magnetic fields , their atmospheres are chemically peculiar - anomalously amplified lines of silicon , strontium , chromium and rare-earth elements are present in the spectra . The intensities of the spectral lines of such stars vary with the strength of the magnetic field. The frequency of these changes coincides with both the period of rotation of the star and the period of change in brightness, ranging from 0.5 to 160 days. The amplitudes of the brightness change are from 0.01 to 0.1 magnitude [1] .
The prototype of the class of variable stars is the star Heart of Karl (α² Hounds Dogs), changing its brightness by 0.14 m with a period of 5.47 days [2] . Of the brightest stars, this type includes Aliot (ε Ursa Major) and Alferatz (α Andromeda).
In the classification of the 4th edition of the General Catalog of Variable Stars, this type of star is denoted by ACV [1] .
Examples of variable stars of type α² Canes of Hounds
The following is a list of variable stars of type α² Hounds Dogs [3] . Only stars whose apparent magnitude is less than 4.5 m , and which, therefore, can usually be seen with the naked eye, daddled in the lap. Their spectral classes are given against the background of the color of these classes. (These colors are taken from the names of spectral types and do not correspond to the observed colors of stars).
| No. | Name | Bayer Designations | Maximum apparent magnitude | Minimum apparent magnitude or amplitude range (*) | Period (days) | Spectrum |
|---|---|---|---|---|---|---|
| one | Aliot | epsilon Ursa Major | 1.76 | 0.02 * | 5,0887 | A0p (Cr-Eu) |
| 2 | Alferats | alpha Andromeda | 2.02 | 2.06 | 0.9662 | B8IVp (Hg-Mn) |
| 3 | Mahasim | Theta Auriga | 2.62 | 2.7 | 1.3735 | B9.5p (Si) |
| four | Karl A Heart | Alpha 2 Hounds Dogs | 2.84 | 2.98 | 5,4694 | B9.5Vp (Si-Cr-Eu) |
| five | - | mu hare | 2.97 | 3.41 | 2 | B9IIIp (Hg-Mn) |
| 6 | - | Alpha Compass | 3.18 | 3.21 | ? | ? |
| 7 | - | Alpha Golden Fish | 3.26 | 3.3 | 2.95 | A0IIIp (Si) |
| eight | Nusakan | beta of the Northern Crown | 3.65 | 3.72 | 18,487 | F0IIIp (Sr-Cr-Eu) |
| 9 | - | phi dragon | 4.22 | 0.04 * | 1.7165 | A0p (Si) |
| ten | - | beta hydra | 4.27 | 0.04 * | 2,344 | B9IIIp (Si) |
| eleven | - | Delta 3 Taurus | 4.29 | 4.32 | 57.25 | A2 / 3IV / Vm |
| 12 | - | Omega Ophiuchus | 4.44 | 4.51 | 2.99 | A7p (Sr-Cr) |
| 13 | - | Iota Cassiopeia | 4.45 | 4.53 | 1.74 | B9p (Cr-Sr) |
| 14 | - | QW Feed | 4.47 | 0.027 * | ? | ? |
Notes
- ↑ 1 2 GAISH . GCVS Variability Types . - Classification of variable stars according to JCHP . Date of treatment September 9, 2008. Archived March 18, 2012.
- ↑ GAISH . GCVS Query Result for alf 2 CVn . Date of treatment September 9, 2008. Archived March 18, 2012.
- ↑ Alcyone.de. variables of a 2 Canum venaticorum type (brighter mag 5.0 in maximum ) .