IAO 2007, Практически тур, Група β — Задача 6. Supernova.
Practical round. Problems to solve · 29 септември 2007 г.
Note for jury and team leaders
Note for jury and team leaders. The proposed sketches are not full; the team leaders have to give more detailed explanations for students. But the correct solutions in the students’ papers (enough for 10pts) may be shorter.
Source annotations
The supernova key prints H=71km/s and Vr≈180000km, with incomplete units, and its second line gives Vr=180000=0.6c. These printed expressions are retained.
Literal source distance unit
The supplied beta practical key prints r=800kpc in step6, then uses 100pc and 700pc in steps8–9. These inconsistent printed units are retained without scientific correction.
Условие
A Hubble diagram is shown in the right plot. Find the apparent magnitude of a hypothetic Supernova of type Ia, if it exploded at a distance Mpc, and it is known that all of the SN Ia have similar absolute magnitudes ().

Решение
Using Hubble formula estimate the receding velocity of our SN Ia. With and one gets .
(where c is the light speed). Thus, to find the redshift we need to use relativistic formula:
Using the mean typical absolute magnitude value for SN Ia and given Hubble diagram we get:
Оригинал в Архива: betapract.jpg · официални решения: practsol2.jpg · допълнителни данни: practsol3.jpg · допълнителни данни: practsol1.jpg