تقرير
The vertical velocity dispersion profile of the Galactic thick disk
| العنوان: | The vertical velocity dispersion profile of the Galactic thick disk |
|---|---|
| المؤلفون: | Bidin, C. Moni, Girard, T. M., Carraro, G., Mendez, R. A., van Altena, W. F., Korchagin, V. I., Casetti-Dinescu, D. I. |
| سنة النشر: | 2007 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics |
| الوصف: | We present the results of radial velocity measurements of 770 thick disk red giants toward the South Galactic Pole, vertically distributed from 0.5 kpc to 5 kpc with respect to the Galactic plane. We find a small gradient in the vertical velocity dispersion (sigma_W) of 3.8+/-0.8 km/s kpc. Even more noteworthy, our values of $\sigma_W$ are small compared to literature values: in the middle of the vertical height range we find sigma_W(z=2kpc)=30 km/s. We found no possible explanation for this small value of sigma_W in terms of sample contamination by thin disk stars, nor by wrong assumptions regarding the metallicity distribution and the derived distances. Comment: 2 pages, 1 figure, proceeding of the XII IAU Latin American Regional Meeting |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/0712.3528 |
| رقم الأكسشن: | edsarx.0712.3528 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |