Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-09-29
Astronomy and Astrophysics
Astrophysics
9 pages, 6 figures (1 color), uses emulateapj5.sty, Accepted for publication in the Astrophysical Journal
Scientific paper
10.1086/324719
We have determined the distance to M33 using single epoch I-band observations of Cepheids based on HST/WFPC2 images of five fields in M33. Combining the HST I-band photometry and the periods determined from the ground-based observations (DIRECT) for 21 Cepheids with log P>0.8 in the sample of 32 Cepheids, we derive a distance modulus of (m-M)_0=24.52+/-0.14(random)+/-0.13(systematic) for an adopted total reddening of M33, E(B-V)=0.20+/-0.04 (E(V-I)=0.27+/-0.05) given by Freedmand et al.(2001), the reddening to the LMC, E(B-V)=0.10, and the distance to the LMC, (m-M)_0=18.50. If the total reddening to M33 of E(B-V)=0.10+/-0.09 given by Freedman, Wilson, and Madore(1991) is used, the Cepheid distance modulus based on the I-band photometry will be increased by 0.20. Metallicity effect on the Cepheid distance to M33 is estimated to be small, delta(m-M)_Z=0.01 to 0.06, which leads to (m-M)_0=24.53 to 24.58 after this metallicity effect correction. Using the Wesenheit W_I, an extinction-free parameter, we derive a similar value, (m-M)_0=24.52+/-0.15(random)+/-0.11(systematic). These results are in reasonable agreement with those based on the ground-based multi-epoch BVRI observations of brighter Cepheids in M33, and are ~0.3 smaller than those based on the tip of the red giant branch and the red clump. It is needed to estimate better the reddening to Cepheids in M33.
Geisler Doug
Gieren Wolfgang
Kim Minsun
Lee Myung Gyoon
Sarajedini Ata
No associations
LandOfFree
Determination of the Distance to M33 Based on Single Epoch I-band HST Observations of Cepheids does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Determination of the Distance to M33 Based on Single Epoch I-band HST Observations of Cepheids, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Determination of the Distance to M33 Based on Single Epoch I-band HST Observations of Cepheids will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-56573