Related papers: The Mira Distance Ladder

A number of recent technical developments, including the Hipparcos satellite, the Hubble Space Telescope fine guidance sensors and long base line near-IR interferometry has made it possible to employ several largely geometrical methods to…

A globular cluster distance scale based on Hipparcos parallaxes of subdwarfs has been used to derive estimates of M_K for cluster Miras, including one in the SMC globular cluster NGC121. These lead to a zero-point of the Mira infrared…

Using a mid-infrared calibration of the Cepheid distance scale based on recent observations at 3.6 um with the Spitzer Space Telescope, we have obtained a new, high-accuracy calibration of the Hubble constant. We have established the mid-IR…

The final efforts of the HST Key Project on the Extragalactic Distance Scale are presented. Four distance indicators, the Surface Brightness Fluctuation method, the Fundamental Plane for early-type galaxies, the Tully-Fisher relation and…

Persistent tension between low-redshift observations and the Cosmic Microwave Background radiation (CMB), in terms of two fundamental distance scales set by the sound horizon $r_d$ and the Hubble constant $H_0$, suggests new physics beyond…

The subject of micro-variability among Mira stars has received increased attention since DeLaverny et al. (1998) reported short-term brightness variations in 15 percent of the 250 Mira or Long Period Variable stars surveyed using the…

The group of Mira-type and semi-regular variables with similar periodicity (multiperiodicty) is analyzed. They have periods of 230-260 days and 140-150 days and show intervals of periodical (Mira-type) variability with relatively high…

We have investigated the mass loss processes in Long Period Variables, by combining radiative transfer modeling with mid-IR imaging and spectroscopic observations. We find a correlation between variability type and temporal variations in…

The local determination of the Hubble Constant sits at a crossroad. Current estimates of the local expansion rate of the Universe differ by about 1.7-sigma, derived from the Cepheid and TRGB based calibrations, applied to type Ia…

We present a new calibration of the peak absolute magnitude of SNe Type Ia based on the Surface Brightness Fluctuations (SBF) method, aimed at measuring the value of the Hubble constant. We build a sample of calibrating anchors consisting…

Mid-infrared bright objects in the direction of the Galactic Bulge were investigated using time series photometry from the MACHO data archive, which led to the discovery of a large number of long-period variables. Among these, a total of…

We report results of our near-IR survey for variables in a field of view of 20 arcmin by 30 arcmin towards the Galactic Center (GC), where we detected 1364 long-period variables. We have established a method for the simultaneous estimation…

The separation between RR Lyrae (RRLs) and Type II Cepheid (T2Cs) variables based on their period is debated. Both types of variable stars are distance indicators and we aim to promote the use of T2Cs as distance indicators in synergy with…

The goal of this paper is to characterise the light variation properties of Mira variables in the Small Magellanic Cloud. We have investigated a combined optical and near infrared multi-epoch dataset of Mira variables based on our…

In this paper, we make a comprehensive determination of the Hubble constant $H_0$ by using two parameters - the B-V color and the rate of decline $\Delta m_{15}$ - to simultaneously standardize the luminosities of all nearby…

There is a persistent tension of about $5\sigma-6\sigma$ between the value of the Hubble constant, as derived from the local distance ladder vs. the cosmic microwave background, signaling either unaccounted for systematics in the…

Type Ia supernovae (SNe\,Ia) serve as crucial cosmological distance indicators because of their empirical consistency in peak luminosity and characteristic light curve decline rates. These properties facilitate them to be standardized…

We carried out a new and sensitive search for long-period variability in the prototype of the Mira class of long-period pulsating variables, o Ceti (Mira A), the closest and brightest Mira variable. We conducted this search using an…

We present an analysis of Type Ia Supernovae (SNe~Ia) from both the Carnegie Supernova Project~I (CSP-I) and II (CSP-II), and extend the Hubble diagram from the optical to the near-infrared wavelengths ($uBgVriYJH$). We calculate the Hubble…

We present an improved measurement of the Hubble constant (H_0) using the 'inverse distance ladder' method, which adds the information from 207 Type Ia supernovae (SNe Ia) from the Dark Energy Survey (DES) at redshift 0.018 < z < 0.85 to…