Related papers: Distance to NGC 0247
We derive a distance of $D = 16.6 \pm 0.3$~Mpc ($\mu=31.10\pm0.04$~mag) to the archetypal narrow-line Seyfert 1 galaxy NGC 4051 based on Cepheid Period--Luminosity relations and new Hubble Space Telescope multiband imaging. We identify 419…
(Abridged) Repeated imaging observations have been made of NGC 3627 with the HST in 1997/98, over an interval of 58 days. Images were obtained on 12 epochs in the F555W band and on five epochs in the F814W band. The galaxy hosted the…
We present Cousins $R$ and $I$ band photometry of variable stars in a $\sim13'\times 13'$ region in the disk of M31 galaxy, obtained during 141 nights. Of the 26 Cepheid variables present in the region, two are newly discovered, 11 are…
Near infrared (IR) studies of Cepheid variables in the LMC take advantage of the reduced light curve amplitude and metallicity dependence at these wavelengths. This work presents such photometry for two young clusters known to contain…
We apply the image subtraction method to re-analyze the ESO Very Large Telescope data on M83 (NGC 5236), obtained and analyzed by Thim et al. Whereas Thim et al. found 12 Cepheids with periods between 12-55 days, we find 112 Cepheids with…
The VISTA Magellanic Cloud (VMC, PI M.R. Cioni) survey is collecting deep Ks-band time-series photometry of the pulsating variable stars hosted by the system formed by the two Magellanic Clouds (MCs) and the "bridge" connecting them. In…
A new compilation of UBV data for stars near the Cepheid S Vul incorporates BV observations from APASS and NOMAD to augment UBV observations published previously. A reddening analysis yields mean colour excesses and distance moduli for two…
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…
The Milky Way Cepheid RS Puppis is a particularly important calibrator for the Leavitt law (the Period-Luminosity relation). It is a rare, long period pulsator (P=41.5 days), and a good analog of the Cepheids observed in distant galaxies.…
(abridged) Recent investigations aimed at estimating the distance to the young LMC cluster NGC1866 have made use of Red Clump stars in the surrounding LMC field, together with empirical and theoretical Main-Sequence fitting methods, and…
We have identified 82 short-period variable stars in Sextans A from deep WFPC2 observations. All of the periodic variables appear to be short-period Cepheids, with periods as small as 0.8 days for fundamental-mode Cepheids and 0.5 days for…
We present measurements of 68 classical Cepheids with periods from 10 to 78 days observed in the near-infrared by the PHAT Program using the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). The combination of HST's resolution…
Polaris is the nearest and brightest classical Cepheid, and pulsates with a period of about 4 days. It has long been known as a single-lined spectroscopic binary with an orbital period of 30 yr. Historical photometric and spectroscopic…
Comparison of the old observations of Cepheids in the Small Magellanic Cloud from the Harvard data archive, with the recent OGLE and ASAS observations allows an estimate of their period changes. All of matched 557 Cepheids are still…
Cepheid masses are particularly necessary to help solving the mass discrepancy, while independent distance determinations provide crucial test of the period-luminosity relation and Gaia parallaxes. We used CHARA/MIRC to measure the…
We performed a new and accurate fit of light and radial velocity curves of the Large Magellanic Cloud (LMC) Cepheid --OGLE-LMC-CEP-0227-- belonging to a detached double-lined eclipsing binary system. We computed several sets of nonlinear,…
Context: The bright southern Cepheid RS Pup is surrounded by a circumstellar nebula reflecting the light from the central star. The propagation of the light variations from the Cepheid inside the dusty nebula creates spectacular light…
We report on a first application of the infrared surface brightness technique on a Cepheid in the Large Magellanic Cloud, the variable HV 12198 in the young globular cluster NGC 1866. From this one star, we determine a distance modulus of…
Employing \emph{VI} images of NGC 2419 acquired over 17 years, light curves for most of the known variables in the field of the cluster are produced. A cluster membership analysis for about 3100 stars in the cluster field with proper…
The rationale behind recent calibrations of the Cepheid PL relation using the Wesenheit formulation is reviewed and reanalyzed, and it is shown that recent conclusions regarding a possible change in slope of the PL relation for short-period…