IAO 2022, Практически тур — Задача 15. Evolutionary phases of stars

II International Remote Astronomy Olympiad — Practical round · 15 октомври 2022 г.

Practical round. Problems to solve

II International Remote Astronomy Olympiad. Matera, Italy, 15–24 October 2022.

Note: problems for Group α — 13, 14, for Group β — 14, 15, for Group γ — 13, 14, 15.

Source notes and availability

The file contains three independent tasks and all tabulated data, theoretical curves and a blank plotting grid. Its fourth page repeats tasks14 and15; this does not create new tasks. The sunspot dates are printed as October2018 and retained. The star table uses labels A–I,L,M as printed. The isochrone diagram numbers its curves but provides no numerical age key, although task15 asks for an age. No matching official solutions or additional reference files were found in the complete same-year archive catalogue.

Условие

The evolutionary phases of the stars in the HR Diagram

In stellar evolution, observational data are often compared with theoretical ones through the use of the HR diagram. The table 15 shows some selected and observed stars (from A to M) of a globular cluster.

15.1 Using the grid provided (in supplement materials) put the observed stars in the plane $(m_B-m_V)$ vs $m_V$.

15.2 Comparing them with the theoretical isochrones (stars of the same age but of different mass, see graph in supplement materials) indicate for the stars A, B, C and G their evolutionary phase. To avoid writing words, use the following abbreviations:

15.3 Estimate the distance module and the age of the cluster.

15.

OBS	$m_b$	$m_v$
A	15,182	14,266
B	20,625	20,059
C	18,709	18,316
D	21,340	20,645
E	22,118	21,285
F	18,274	17,739
G	15,394	14,837
H	15,675	14,828
I	17,436	16,731
L	20,286	19,772
M	16,100	15,301

Theoretical isochrones

15. Grid

Решение

Теми и трудност

Трудност: неоценена.

Звезди · Диаграма на Херцшпрунг–Ръсел · Звездна еволюция

Предпоставки: Разширена олимпиадна подготовка

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Оригинал в Архива: prac-IRAO2022.pdf