First results from HIPPARCOS trigonometrical parallaxes of Mira-type variables

Leeuwen, F. van; Feast, M. W.; Whitelock, P. A.; Yudin, B. F.

doi:10.1093/mnras/287.4.955

Cited by 126 publications

(91 citation statements)

References 17 publications

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“…As discussed in vL00, the size of U Her indicates that it pulsates in fundamental mode. R Cas is also thought to be a fundamental mode pulsator as shown in van Leeuwen (1997). This was determined by observations of the stellar radius, which seemed to be smaller than expected for overtone pulsators.…”

Section: Distancesmentioning

confidence: 93%

“…At the moment these investigations are based on Hipparcos distances, which excludes the stars with high mass-loss because they tend to be too obscured in the optical. A similar outstanding debate considers the precise pulsation mode of Mira variables; this requires the conversion of IR interferometry data into absolute diameters and hence distances (van Leeuwen et al 1997;Wood 1998). …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

VLBI astrometry of circumstellar OH masers: Proper motions and parallaxes of four AGB stars

Vlemmings

Langevelde

Diamond

et al. 2003

A&A

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Abstract. The main-line OH masers around 4 AGB stars have been observed with the NRAO Very Long Baseline Array (VLBA) at 8 epochs over a period of 2.5 yrs. Using a phase referencing technique, the position of the most compact maser spot of each star was monitored with respect to two extragalactic reference sources. For U Her and W Hya, we observe the most blue-shifted maser spot, while for R Cas and S CrB we only detect a compact red-shifted maser spot. We managed to determine an accurate proper motion and parallax for U Her, R Cas and S CrB, while additional motion of the compact blue-shifted maser of W Hya is shown to possibly be related to the stellar pulsation. The motion and radio position are compared with the stellar trajectory and absolute optical position determined by the Hipparcos satellite. For U Her and W Hya, the most blue-shifted maser is consistent with the amplified stellar image. The new distances are compared with several published P−L relations, and in this respect the VLBI distances seem an improvement upon the Hipparcos distances.

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Section: Distancesmentioning

confidence: 93%

Section: Introductionmentioning

confidence: 99%

VLBI astrometry of circumstellar OH masers: Proper motions and parallaxes of four AGB stars

Vlemmings

Langevelde

Diamond

et al. 2003

A&A

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“…the period-radius relationship for Mira stars pulsating in the fundamental mode (van Leeuwen et al 1997), a radius of 258 R is inferred from the 222-d period, assuming a mass of 1.5 M . Adopting a mass of 1 M for the companion, for the Roche radius to be larger than the stellar radius requires an orbital period of at least 1130 d, which is inconsistent with the observed value of 576 d. What then is the origin of this 576 d period?…”

Section: Fig 12mentioning

confidence: 99%

Spectroscopic binaries among Hipparcos M giants

Famaey¹,

Pourbaix²,

Frankowski³

et al. 2009

A&A

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Context. This paper is a follow-up on the vast effort to collect radial velocity data for stars belonging to the Hipparcos survey. Aims. We aim at extending the orbital data available for binaries with M giant primaries. The data presented in this paper will be used in the companion papers of this series to (i) derive the binary frequency among M giants and compare it to that of K giants (Paper II); and (ii) analyse the eccentricity -period diagram and the mass-function distribution (Paper III). Methods. Keplerian solutions are fitted to radial-velocity data. However, for several stars, no satisfactory solution could be found, even though the radial-velocity standard deviation is greater than the instrumental error, because M giants suffer from intrinsic radialvelocity variations due to pulsations. We show that these intrinsic radial-velocity variations can be linked with both the average spectral-line width and the photometric variability. Results. We present an extensive collection of spectroscopic orbits for M giants with 12 new orbits, plus 17 from the literature. On top of these, 1 preliminary orbit yielded an approximate value for the eccentricity and the orbital period. Moreover, to illustrate how the large radial-velocity jitter present in Mira and semi-regular variables may easily be confused with orbital variations, we also present examples of pseudo-orbital variations (in S UMa, X Cnc, and possibly in HD 115 521, a former IAU radial-velocity standard). Because of this difficulty, M giants involving Mira variables were excluded from our monitored sample. We finally show that the majority of M giants detected as X-ray sources are actually binaries. Conclusions. The data presented in this paper considerably increase the orbital data set for M giants, and will allow us to conduct a detailed analysis of the eccentricity -period diagram in a companion paper (Paper III).

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“…Long noted for its peculiar elliptical visible nebulosity extending up to 2@ (Ðrst reported in Lampland 1923), this star has recently been subject to intense scrutiny with the latest generation of astronomical instrumentation both on the ground and in space. Much of this attention can be traced to the detection in the optical (Wallerstein 1980 ;Herbig 1980) and radio (Sopka et al 1982) of what is believed to be the nearest astrophysical jet to the Earth (D200 pc ; Van Leeuwen et al 1997 ;Hollis, Pedelty, & Lyon 1997). Thought to originate in the accretion disk around an unseen hot subdwarf, this jet has been studied extensively at UV, optical, and radio wavelengths (e.g., Burgarella, Vogel, & Paresce 1992 ;Paresce & Hack 1994 ;Lehto & Johnson 1992).…”

Section: Introductionmentioning

confidence: 99%

Near‐ and Mid‐Infrared Subarcsecond Structure of the Dusty Symbiotic Star R Aquarii

Tuthill

Danchi

Hale

et al. 2000

ApJ

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The results of a high-resolution interferometric campaign targeting the symbiotic long-period variable (LPV) R Aqr are reported. With both near-infrared measurements on baselines out to 10 m and midinfrared data extending to 32 m, we have been able to measure the characteristic sizes of regions from the photosphere of the LPV and its extended molecular atmosphere out to the cooler circumstellar dust shell. The near-infrared data were taken using aperture-masking interferometry on the Keck I telescope and show R Aqr to be partially resolved for wavelengths out to 2.2 km but with a marked enlargement, possibly due to molecular opacity, at 3.1 km. Mid-infrared interferometric measurements were obtained with the Univeristy of California, Berkeley, infrared spatial interferometer (ISI) operating at 11.15 km from 1992 to 1999. Although this data set is somewhat heterogeneous with incomplete coverage of the Fourier plane and sampling of the pulsation cycle, clear changes in the mid-infrared brightness distribution were observed, both as a function of position angle on the sky and as a function of pulsation phase. Spherically symmetric radiative transfer calculations of uniform-outÑow dust shell models produce brightness distributions and spectra which partially explain the data ; however, limitations to this approximation are noted. Evidence for signiÐcant deviation from circular symmetry was found in the mid-infrared and more tentatively at 3.08 km in the near-infrared ; however, no clear detection of binarity or of non-LPV elements in the symbiotic system is reported.

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First results from HIPPARCOS trigonometrical parallaxes of Mira-type variables

Cited by 126 publications

References 17 publications

VLBI astrometry of circumstellar OH masers: Proper motions and parallaxes of four AGB stars

VLBI astrometry of circumstellar OH masers: Proper motions and parallaxes of four AGB stars

Spectroscopic binaries among Hipparcos M giants

Near‐ and Mid‐Infrared Subarcsecond Structure of the Dusty Symbiotic Star R Aquarii

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