Related papers: A New Cepheid Distance Measurement and Method for …
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 present new near-IR light curves for six Cepheids in the young blue LMC cluster NGC1866 as well as high precision radial velocity curves for ten Cepheids in NGC1866 and two in NGC2031. For the six Cepheids in NGC1866 with new J and K…
We report a new geometric maser distance estimate to the active galaxy NGC 4258. The data for the new model are maser line-of-sight velocities and sky positions from 18 epochs of Very Long Baseline Interferometry observations, and…
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…
We report observations of two nearby Type Ia supernovae (SNe Ia) for which observations of Cepheid variables in the host galaxies have been obtained with the Hubble Space Telescope: SN 1994ae in NGC 3370 and SN 1998aq in NGC 3982. For NCG…
In Yoshii et al. (2014), we described a new method for measuring extragalactic distances based on dust reverberation in active galactic nuclei (AGNs), and we validated our new method with Cepheid variable stars. In this paper, we validate…
We present the first Herschel PACS and SPIRE images of the low-metallicity galaxy NGC6822 observed from 70 to 500 mu and clearly resolve the HII regions with PACS and SPIRE. We find that the ratio 250/500 is dependent on the 24 mu surface…
We identify and phase a sample of 81 Cepheids in the maser-host galaxy NGC 4258 using the Large Binocular Telescope (LBT), and obtain calibrated mean magnitudes in up to 4 filters for a subset of 43 Cepheids using archival HST data. We…
Using the Hubble Space Telescope (HST) 37 long-period Cepheid variables have been discovered in the Fornax Cluster spiral galaxy NGC 1365. The resulting V and I period-luminosity relations yield a true distance modulus of 31.35 +/- 0.07…
Stellar distance is an important basic parameter in stellar astrophysics. Stars in a cluster are thought to be formed coevally from the same interstellar cloud of gas and dust. They are therefore expected to have common properties. These…
The Carnegie-Chicago Hubble Program (CCHP) is re-calibrating the extragalactic SN Ia distance scale using exclusively Population II stars. This effort focuses on the Tip of the Red Giant Branch (TRGB) method, whose systematics are entirely…
The Carnegie Hubble Program (CHP) is designed to improve the extragalactic distance scale using data from the post-cryogenic era of Spitzer. The ultimate goal is a determination of the Hubble constant to an accuracy of 2%. This paper is the…
The distance to NGC3982, host galaxy to the Type Ia supernova SN1998aq, is derived using 32 Cepheids discovered in archival multi-epoch Hubble Space Telescope observations. Employing recent Large Magellanic Cloud Cepheid period-luminosity…
We report BV(RI)c CCD photometric data for a group of seven Cepheid variables in the young, rich cluster NGC 1866 in the Large Magellanic Cloud. The photometry was obtained as part of a program to determine accurate distances to these…
We present a measurement of the Hubble Constant based on Cepheid distances to 27 galaxies within 20 Mpc. We take the Cepheid data from published measurements by the Hubble Telescope Key Project on the Distance Scale (H0KP). We calibrate the…
Mass loss shapes the fate of massive stars; however, the physical mechanism causing it remains uncertain. We present a comprehensive analysis of seven red supergiants, for which we searched evidence of episodic mass loss, in three…
Cepheids have been observed in NGC 5236 (M 83) using the ANTU (UT1) 8.2 meter telescope of the ESO VLT with FORS1. Observations over 34 epochs in V and I have been made between January 2000 and July 2001. Twelve Cepheid candidates have…
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…
We present a complete theoretical scenario for classical Cepheids in the most commonly used HST/WFC3 filters, going from optical (F555W, F606W and F814W) to near-infrared (F160W) bands. The importance of such a study is related to the…
We present Period-Luminosity-Color and Period-Luminosity relations of classical Cepheids constructed for about 1280 Cepheids from the LMC and 2140 from the SMC. High quality BVI observations (120-360 epochs in the I-band and 15-40 in the…