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Related papers: Pulsating B and Be stars in the Magellanic Clouds

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We present an analysis of high-resolution FLAMES spectra of approximately 50 early B-type stars in three young clusters at different metallicities, NGC6611 in the Galaxy, N11 in the Large Magellanic Cloud (LMC) and NGC346 in the Small…

Spectroscopic observations of hot stars belonging to the young cluster LMC-NGC 2004 and its surrounding region were carried out with the VLT-GIRAFFE facilities in MEDUSA mode. We determine fundamental parameters (Teff, logg, vsini, and…

Pulsating variable stars can be powerful tools to study the structure, formation and evolution of galaxies. I discuss the role that the Magellanic Clouds' pulsating variables play in our understanding of the whole Magellanic System, in…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Gisella Clementini

We report on the study of the population of B and Be stars in SMC young clusters, performed with the Wide Field Imager in slitless spectroscopic mode at ESO/T2.2m with a filter centered at Halpha. First, we explain the reduction methods we…

I present measurements of the projected rotational velocities of a sample of 100 early B-type main-sequence stars in the Large Magellanic Cloud. This is the first extragalactic study of the distribution of stellar rotational velocities. The…

Astrophysics · Physics 2009-11-10 Stefan C. Keller

Recent theoretical predictions for low metallicity massive stars predict that these stars should have drastically reduced equatorial winds (mass loss) while on the main sequence, and as such should retain most of their angular momentum.…

Astrophysics · Physics 2009-11-10 Laura R. Penny , Amanda J. Sprague , George Seago , Douglas R. Gies

We present ultraviolet spectra from the Space Telescope Imaging Spectrograph (STIS) of 12 early B-type stars in the Small Magellanic Cloud (SMC), comprising 9 supergiants and 3 giants. A morphological comparison with Galactic analogues is…

Astrophysics · Physics 2009-11-10 C. J. Evans , D. J. Lennon , N. R. Walborn , C. Trundle , S. A. Rix

A thorough analysis of the OGLE-II time-series photometry of the Large Magellanic Cloud bar supplemented by similar data from the MACHO database led us to the discovery of three Beta Cephei-type stars. These are the first known…

Astrophysics · Physics 2009-11-07 A. Pigulski , Z. Kolaczkowski

We present a proper motion investigation of a sample of Be star candidates towards the Magellanic Clouds, which has resulted in the identification of separate populations, in the Galactic foreground and in the Magellanic background. Be…

Astrophysics of Galaxies · Physics 2017-06-28 Katherine Vieira , Alejandro García-Varela , Beatriz Sabogal

We present the properties of the recently discovered class of variable stars, Blue Large-Amplitude Pulsators (BLAPs). These extremely rare, short-period pulsating objects were detected thanks to regular, high-cadence observations of…

Solar and Stellar Astrophysics · Physics 2018-02-14 Pawel Pietrukowicz

To study the effects of metallicity and evolution on the appearance of the Be phenomenon in the B stars population, we observed several fields in the Large and Small Magellanic Clouds (LMC and SMC, respectively) which have different…

The stability of retrograde mixed modes in rotating B-type stars is investigated. It is found that these modes are susceptible to kappa-mechanism excitation, due to the iron opacity bump at log T ~ 5.3. The findings are discussed in the…

Astrophysics · Physics 2007-05-23 Rich Townsend

Mass loss through a stellar wind is an important physical process that steers the evolution of massive stars and controls the properties of their end-of-life products, such as the supernova type and the mass of compact remnants. For an…

The Hubble Space Telescope has provided the first clear evidence for weaker winds of metal-poor massive stars in the Small Magellanic Cloud, confirming theoretical predictions of the metallicity dependence of mass-loss rates and wind…

Astrophysics · Physics 2017-03-14 Daniel J. Lennon

We present the results of a study of a large sample of A and Am stars with spectral types from LAMOST and light curves from WASP. We find that, unlike normal A stars, $\delta$ Sct pulsations in Am stars are mostly confined to the effective…

Analysis of the longterm photometric variability of 7 Be/X-ray-pulsar systems in the Small Magellanic Cloud has been carried out. We find a variety of types of variability are present, including: longterm irregular changes, periodic orbital…

Astrophysics · Physics 2008-11-26 P. C. Schmidtke , A. P. Cowley

Following the discovery of blue large-amplitude pulsators (BLAPs) by the OGLE survey, additional hot, high-amplitude pulsating stars have been discovered by the Zwicky Transient Facility. It has been proposed that all of these objects are…

Solar and Stellar Astrophysics · Physics 2019-12-11 Conor M. Byrne , C. Simon Jeffery

The long-time photometric surveys in a few young open clusters allowed to identify the light variability in stars located on the HR diagram between the well defined $\delta$ Scuti variables and Slowly Pulsating B-type stars. Several objects…

Solar and Stellar Astrophysics · Physics 2017-11-08 Jadwiga Daszynska-Daszkiewicz , Przemyslaw Walczak , Alexey Pamyatnykh

The analysis of the light curves of 48 B-type stars observed by Kepler is presented. Among these are 15 pulsating stars, all of which show low frequencies characteristic of SPB stars. Seven of these stars also show a few weak, isolated high…

Analyzing IUE ultraviolet spectra of beta Cep pulsating stars we have noticed that multiperiodic variables have a larger mean metal abundance in the photosphere, [m/H], than monoperiodic ones. We apply statistical tests to verify this…

Astrophysics · Physics 2009-11-10 J. Daszynska-Daszkiewicz , E. Niemczura