Related papers: The Araucaria Project
We have obtained deep images in the near-infrared J and K filters for several fields in the Local Group galaxy WLM. We report intensity mean magnitudes for 31 Cepheids located in these fields which we previously discovered in a wide-field…
We have conducted an extensive wide-field imaging survey for Cepheid variables in the Local Group irregular galaxy WLM. From data obtained on 101 nights, we have discovered 60 Cepheids which include 14 of the 15 Cepheid variables previously…
We have obtained mosaic images of NGC 6822 in V and I bands on 77 nights. From these data, we have conducted an extensive search for Cepheid variables over the entire field of the galaxy, and we have found 116 such variables with periods…
Based on new observations and improved modeling techniques, we have reanalyzed seven Cepheids in the Large Magellanic Cloud. Improved physical parameters have been determined for the exotic system OGLE LMC-CEP-1718 composed of two…
Motivated by an amazing range of reported distances to the nearby Local Group spiral galaxy M33, we have obtained deep near-infrared photometry for 26 long-period Cepheids in this galaxy with the ESO VLT. From the data we constructed…
We have detected, for the first time, Cepheid variables in the Sculptor Group spiral galaxy NGC 7793. From wide-field images obtained in the optical V and I bands on 56 nights in 2003-2005, we have discovered 17 long-period (24-62 days)…
The quantitative analysis of low resolution spectra of A and B supergiants is used to determine a distance modulus of 24.99 +/- 0.10 mag (995 +/- 46 Kpc) to the Local Group galaxy WLM. The analysis yields stellar effective temperatures and…
We have measured accurate near-infrared magnitudes in the J and K bands of 39 Cepheid variables in IC 1613 with well-determined periods and optical VI light curves. Using the template light curve approach of Soszy{\'n}ski, Gieren and…
We present an investigation of Cepheid distances using theory and observations. Cepheid models indicate that the slope of the Period-Luminosity (P-L) relation covering the entire period range (0.40<= logP <=2.0) becomes steeper when moving…
Using high-quality observed period-luminosity relations in both Magellanic Clouds in VIJHKs bands and optical and near-infrared Wesenheit indices we determine the effect of metallicity on Cepheid P-L relations by comparing the relative…
In a previous paper, we reported on the discovery of more than a hundred new Cepheid variables in the Sculptor Group spiral NGC 300 from wide-field images taken in the B and V photometric bands at ESO/La Silla. In this paper, we present…
A sample of 37 Galactic, 10 LMC and 6 SMC cepheids is compiled for which individual metallicity estimates exist and BVIK photometry in almost all cases. The Galactic cepheids all have an individual distance estimate available. For the MC…
(ABRIDGED) We have applied the near-IR Barnes-Evans realization of the Baade-Wesselink method as calibrated by Fouque & Gieren (1997) to five metal-poor Cepheids with periods between 13 and 17 days in the Small Magellanic Cloud as well as…
Uncertainty in the metal abundance dependence of the Cepheid variable period- luminosity (PL) relation remains one of the outstanding sources of systematic error in the extragalactic distance scale and Hubble constant. To test for such a…
We have used the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope to obtain V and I images of seven nearby galaxies. For each, we have measured a distance using the tip of the red giant branch (TRGB) method. By…
In this paper the synthetic period-luminosity (P-L) relations in Spitzer's IRAC bands, based on a series of theoretical pulsation models with varying metal and helium abundance, were investigated. Selected sets of these synthetic P-L…
Based on observations of NGC 300, obtained with the Wide-Field Camera at the 2.2 m ESO/MPI telescope during 29 nights spread over a 5.3 month interval, 117 Cepheids and 12 Cepheid candidates were found which cover the period range from 115…
We present results of the search for Cepheids in the galaxy IC1613 carried out as a sub-project of the OGLE-II microlensing survey. 138 Cepheids were found in the 14.2x14.2 arcmin region in the center of the galaxy. We present light curves,…
We have obtained mosaic images of NGC 3109 in the V and I bands on 74 nights, spanning approximately one year. From these data, we have conducted an extensive search for Cepheid variables over the entire field of the galaxy, resulting in…
We determine Period-Luminosity relations for Milky Way Cepheids in the optical and near-IR bands. These relations can be used directly as reference for extra-galactic distance determination to Cepheid populations with solar metallicity, and…