Richard Irving Anderson

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We have estimated relativistic corrections for cosmic distance estimates based on stellar standard candles such as classical Cepheids and stars near the tip of the red giant branch (TRGB stars) with the goal of enabling a future unbiased 1% measurement of ...

Gaia Data Release 3 provides novel flux-calibrated low-resolution spectrophotometry for similar or equal to 220 million sources in the wavelength range 330 nm

Context. Di ffuse interstellar bands (DIBs) are common interstellar absorption features in spectroscopic observations but their origins remain unclear. DIBs play an important role in the life cycle of the interstellar medium (ISM) and can also be used to t ...

The Gaia Galactic survey mission is designed and optimized to obtain astrometry, photometry, and spectroscopy of nearly two billion stars in our Galaxy. Yet as an all-sky multi-epoch survey, Gaia also observes several million extragalactic objects down to ...

We report the discovery of a surprising binary configuration of the double-mode Cepheid OGLE-LMC-CEP-1347 pulsating in the first (P-1= 0.690 days) and second-overtone (P-2= 0.556 days) modes. The orbital period (P-orb= 59 days) of the system is five times ...

We investigated the occurrence of classical (type-I) Cepheid variable stars (henceforth Cepheids) in dynamically evolving star clusters from birth to an age of approximately 300 Myr. The clusters are modelled by the Aarseth code NBODY6, and they feature a ...

Context. The photometric observations from the recent decade revolutionized our view on classical pulsators. Low-amplitude signals have been detected photometrically in addition to the dominant high-amplitude radial mode pulsations in many RR Lyrae stars a ...

The tip of the red giant branch (TRGB) provides a luminous standard candle for constructing distance ladders to measure the Hubble constant. In practice, its measurements via edge-detection response (EDR) are complicated by the apparent fuzziness of the ti ...

Classical Cepheids provide valuable insights into the evolution of stellar multiplicity among intermediate-mass stars. Here, we present a systematic investigation of single-lined spectroscopic binaries (SB1s) based on high-precision velocities measured by ...

Context. Some of the youngest stars (age less than or similar to 10 Myr) are clustered, while many others are observed scattered throughout star forming regions or in complete isolation. It has been intensively debated whether such scattered or isolated st ...

Context. The Gaia DR3 catalogue contains, for the first time, about 800 000 solutions with either orbital elements or trend parameters for astrometric, spectroscopic, and eclipsing binaries, and combinations of these three.Aims. With this paper, we aim to ...

Known for their large amplitude radial pulsations, classical Cepheids are critical standard candles in astrophysics. However, they also exhibit various pulsational irregularities and additional signals that provide deeper insights into their structure and ...

The tip of the red giant branch (TRGB) is an important standard candle for determining luminosity distances. Although several 105 small-amplitude red giant stars (SARGs) have been discovered, variability was previously considered irrelevant for the TRGB as ...

We have conducted a search for open clusters in the vicinity of classical Galactic Cepheids based on high-quality astrometry from the third data release (DR3) of the ESA mission Gaia to improve the calibration of the Leavitt law (LL). Our approach requires ...

Context. Classical Cepheids are primary distance indicators and a crucial stepping stone in determining the present-day value of the Hubble constant H-0 to the precision and accuracy required to constrain apparent deviations from the ACDM Concordance Cosmo ...

Context. The third Gaia data release provides photometric time series covering 34 months for about 10 million stars. For many of those stars, a characterisation in Fourier space and their variability classification are also provided. This paper focuses on ...

Context. The motion of stars has been used to reveal details of the complex history of the Milky Way, in constant interaction with its environment. Nevertheless, to reconstruct the Galactic history puzzle in its entirety, the chemo-physical characterisatio ...

We investigate the absolute calibration of the tip of the red giant branch (TRGB) in the Small Magellanic Cloud (SMC) using small amplitude red giant stars (SARGs) classified by the Optical Gravitational Lensing Experiment (OGLE). We show that all stars ne ...

In this paper, we describe the wide-field spectroscopic survey telescope (WST) project. WST is a 12-metre wide-field spectroscopic survey telescope with simultaneous operation of a large field-of-view (3 sq. degree), high-multiplex (20,000) multi-object sp ...

Context. Gaia Data Release 3 (DR3) provides a wealth of new data products for the astronomical community to exploit, including astrophysical parameters for half a billion stars. In this work, we demonstrate the high quality of these data products and illus ...

Richard Irving Anderson

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Relativistic corrections for measuring Hubble's constant to 1% using stellar standard candles

The Galaxy in your preferred colours: Synthetic photometry from Gaia low-resolution spectra

Exploring and mapping the diffuse interstellar band at 862nm

Gaia Data Release 3: The extragalactic content

Discovery of a Binary-origin Classical Cepheid in a Binary System with a 59 day Orbital Period

On the dynamical evolution of Cepheids in star clusters & x22c6

The VELOCE modulation zoo I. Spectroscopic detection of non-radial modes in the first-overtone Cepheids BG Crucis, QZ Normae, V0391 Normae, and V0411 Lacertae

CATS: The Hubble Constant from Standardized TRGB and Type Ia Supernova Measurements

VELOcities of CEpheids (VELOCE): II. Systematic search for spectroscopic binary cepheids

Do the majority of stars form as gravitationally unbound?

Gaia Data Release 3 Stellar multiplicity, a teaser for the hidden treasure

The VELOCE modulation zoo III. Detecting additional pulsation modes in optical spectra of classical Cepheids using semi-partial distance correlation periodograms

Small-amplitude Red Giants Elucidate the Nature of the Tip of the Red Giant Branch as a Standard Candle

A 0.9% calibration of the Galactic Cepheid luminosity scale based on Gaia DR3 data of open clusters and Cepheids

The iron and oxygen content of LMC Classical Cepheids and its implications for the extragalactic distance scale and Hubble constant Equivalent width analysis with Kurucz stellar atmosphere models

Pulsations in main sequence OBAF-type stars

Chemical cartography of the Milky Way

Calibrating and Standardizing the Tip of the Red Giant Branch in the Small Magellanic Cloud Using Small-amplitude Red Giants

WST - Widefield Spectroscopic Telescope: Motivation, science drivers and top-level requirements for a new dedicated facility

A golden sample of astrophysical parameters