The distance to the Leo I dwarf spheroidal galaxy from the Red Giant Branch Tip ⋆
نویسندگان
چکیده
We present V and I photometry of a 9.4 ′ × 9.4 ′ field centered on the dwarf spheroidal galaxy Leo I. The I magnitude of the tip of the Red Giant Branch is robustly estimated from two different datasets (I T RGB = 17.97 +0.05 −0.03). From this estimate, adopting [M/H] ≃ −1.2 from the comparison of RGB stars with Galactic templates, we obtain a distance modulus (m − M) 0 = 22.02 ± 0.13, corresponding to a distance D = 254 +16 −19 Kpc.
منابع مشابه
The Red Giant Branch Tip and Bump of the Leo II dwarf spheroidal galaxy
We present V and I photometry of a 9.4 × 9.4 field centered on the dwarf spheroidal galaxy Leo II. The Tip of the Red Giant Branch is identified at I = 17.83± 0.03 and adopting 〈[M/H ]〉 = −1.53±0.2 from the comparison of RGB stars with Galactic templates, we obtain a distance modulus (m − M)0 = 21.84 ± 0.13, corresponding to a distance D = 233 ± 15 Kpc. Two significant bumps have been detected ...
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