English
Related papers

Related papers: Discovery of non-radial pulsations in the spectros…

200 papers

We present the discovery of a further five recycled pulsar systems in the mid-Galactic latitude portion of the High Time Resolution Universe (HTRU) Survey. The pulsars have rotational periods ranging from 2 ms to 66 ms, and four are in…

We obtained time-resolved optical photometry and spectroscopy of the nova-like variable KR Aurigae in the low state. The spectrum reveals a DAB white dwarf and a mid-M dwarf companion. Using the companion star's $i$-band ellipsoidal…

A star's rotation rate is difficult to estimate without surface inhomogeneities such as dark or bright spots. This paper presents asteroseismic results to determine the rotation rates of $\delta$ Sct-type pulsating primary stars in two…

Solar and Stellar Astrophysics · Physics 2023-05-10 Seung-Lee Kim

We present the first X-ray observation of the energetic millisecond pulsar binary PSR J1431-4715, performed with XMM-Newton and complemented with fast optical multi-band photometry acquired with the ULTRACAM instrument at ESO-NTT. It is…

High Energy Astrophysical Phenomena · Physics 2024-09-04 D. de Martino , A. Phosrisom , V. S. Dhillon , D. F. Torres , F. Coti Zelati , R. P. Breton , T. R. Marsh , A. Miraval Zanon , N. Rea , A. Papitto

Thanks to the space missions CoRoT and Kepler new oscillation frequencies have been discovered in the Fourier spectra of Blazhko RR Lyrae stars. The period doubling (PD) yields half-integer frequencies between the fundamental mode and its…

Solar and Stellar Astrophysics · Physics 2015-06-17 József M. Benkő , Róbert Szabó

The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (muchfuss) aims to discover subdwarf-B stars with massive compact companions such as overmassive white dwarfs (M > 1.0 M_sun), neutron stars or black holes.…

We have examined high accuracy radial velocities of Cepheids to determine the binary frequency. The data are largely from the CORAVEL spectrophotometer and the Moscow version, with a typical uncertainty of $\leq1$~km~s$^{-1}$, and a time…

We report the detection of periodic variations on the T_eff ~32 000 K DA white dwarf star HE 1017-1352. We obtained time series photometry using the 4.1 m SOAR telescope on three separate nights for a total of 16.8 h. From the frequency…

Solar and Stellar Astrophysics · Physics 2020-06-10 Alejandra D. Romero , L. Antunes Amaral , S. O. Kepler , L. Fraga , D. Kurtz , H. Shibahashi

We report the phase-connected timing ephemeris, polarization pulse profiles, Faraday rotation measurements, and Rotating-Vector-Model (RVM) fitting results of twelve millisecond pulsars (MSPs) discovered with the Five-hundred-meter Aperture…

We have investigated the F0V star V398\,Aurigae (= 9 Aur) under the assumption that it is undergoing non-radial gravity mode oscillations and that the two principal periods given by Krisciunas et al. (1995) are correct. We find that the two…

Astrophysics · Physics 2015-06-24 Conny Aerts , Kevin Krisciunas

Pulsating stars in eclipsing binary systems play an important role in asteroseismology. The combination of their spectroscopic and photometric orbital solutions can be used to determine, or at least to constrain, the masses and radii of…

Solar and Stellar Astrophysics · Physics 2014-03-05 D. Drobek , A. Pigulski

HR 1217 is a prototypical rapidly oscillating Ap star that has presented a test to the theory of nonradial stellar pulsation. Prior observations showed a clear pattern of five modes with alternating frequency spacings of 33.3 microHz and…

Astrophysics · Physics 2009-11-07 D. W. Kurtz , S. D. Kawaler , R. L. Riddle et al.

Systematic search for multiperiodicity in the LMC Cepheids (Moskalik, Kolaczkowski & Mizerski 2004) has led to discovery of low amplitude nonradial modes in a substantial fraction of overtone pulsators. We present detailed discussion of…

Astrophysics · Physics 2008-07-04 P. Moskalik , Z. Kolaczkowski

PSR J1744-3922 is a binary pulsar exhibiting highly variable pulsed radio emission. We report on a statistical multi-frequency study of the pulsed radio flux variability which suggests that this phenomenon is extrinsic to the pulsar and…

In the first spectroscopic campaign for a PG 1716 variable (or long-period pulsating subdwarf B star), we succeeded in detecting velocity variations due to g-mode pulsations at a level of 1.0-1.5 km/s.The observations were obtained during…

On the basis of our new simultaneous photometry and spectroscopy (885 uvby differential measurements in 11 nights and 154 spectrograms of the FeII 4508 A region in 5 nights), we can detect 12 probable periodicities in the variability…

Astrophysics · Physics 2007-05-23 M. Bossi , L. Mantegazza , N. S. Nunez

A search was carried out for pulsars with periods (P) from 2 to 90 s in daily observations carried out over an interval of 5 years in a area measuring 6300 sq.deg. The data was obtained on a Large Phased Array (LPA) at a frequency of 111…

High Energy Astrophysical Phenomena · Physics 2025-04-22 S. A. Tyul'bashev , G. E. Tyul'basheva

We analyze data on pulsation amplitudes and phases for two $\beta$ Cephei stars, $\delta$ Cet and $\nu$ Eri. Str\"omgren photometry and radial velocity measurements are used simultaneously to obtain constraints on mean parameters of the…

Astrophysics · Physics 2009-11-11 J. Daszynska-Daszkiewicz , W. A. Dziembowski , A. A. Pamyatnykh

Exoplanet properties crucially depend on their host stars' parameters. In case the exoplanet host star shows pulsations, asteroseismology can be used for an improved description of the stellar parameters. We aim to revisit the pulsational…

We have detected significant Rotation Measure variations for 9 bright pulsars, as a function of pulse longitude. An additional sample of 10 pulsars showed a rather constant RM with phase, yet a small degree of RM fluctuation is visible in…

Astrophysics of Galaxies · Physics 2015-05-13 A. Noutsos , A. Karastergiou , M. Kramer , S. Johnston , B. W. Stappers
‹ Prev 1 4 5 6 7 8 10 Next ›