The giant anteater Myrmecophaga tridactyla is categorized as Vulnerable on the IUCN Red List, and is extinct in several locations as a result of environmental pressures. We present the first records of the giant anteater in the largest continuous expanse of the Atlantic Forest biome, in southern Brazil, highlighting its occurrence in the highlands of the Serra do Mar mountain range. During a camera-trapping survey of medium and large mammals we obtained two records of the species, one in 2013 and the other in 2014. These records from dense rainforest highlands indicate the importance of this environment for the giant anteater and highlight these areas as possible foci for future studies of the species. In addition, we present a review of the species’ occurrence in protected areas in Brazil, to provide a resource for the conservation of this species and for future re-evaluations.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Magnetic fields of cool stars can be directly investigated through the study of the Zeeman effect on photospheric spectral lines using several approaches. With spectroscopic measurement in unpolarised light, the total magnetic flux averaged over the stellar disc can be derived but very little information on the field geometry is available. Spectropolarimetry provides a complementary information on the large-scale magnetic topology. With Zeeman-Doppler Imaging (ZDI), this information can be retrieved to produce a map of the vector magnetic field at the surface of the star, and in particular to assess the relative importance of the poloidal and toroidal components as well as the degree of axisymmetry of the field distribution.

The development of high-performance spectropolarimeters associated with multi-lines techniques and ZDI allows us to explore magnetic topologies throughout the Hertzsprung-Russel diagram, on stars spanning a wide range of mass, age and rotation period. These observations bring novel constraints on magnetic field generation by dynamo effect in cool stars. In particular, the study of solar twins brings new insight on the impact of rotation on the solar dynamo, whereas the detection of strong and stable dipolar magnetic fields on fully convective stars questions the precise role of the tachocline in this process.

Among the A/B stars, about 5% host large-scale organised magnetic fields. These magnetic stars show also abundance anomalies in their spectra, and are therefore called the magnetic Ap/Bp stars. Most of these stars are also slow rotators compared to the normal A and B stars. Today, one of the greatest challenges concerning the Ap/Bp stars is to understand the origin of their slow rotation and their magnetic fields. The favoured hypothesis for the latter is that the fields are fosils, which implies that the magnetic fields subsist throughout the different evolutionary phases, and in particular during the pre-main sequence phase. The existence of magnetic fields at the pre-main sequence phase is also required to explain the slow rotation of Ap/Bp stars. 
During the last 3 years we performed a spectropolarimetric survey of the Herbig Ae/Be stars in the field and in young clusters, in order to investigate their magnetism and rotation. These investigations have resulted in the detection and/or confirmation of magnetic fields in 8 Herbig Ae/Be stars, ranging in mass from 2 to nearly 15 solar masses. In this paper I will present the results of our survey, as well as their implications for the origin and evolution of the magnetic fields and rotation of the A and B stars.

Sun-like stars are able to continuously generate a large-scale magnetic field through the action of a dynamo. Various physical parameters of the star are able to affect the dynamo output, in particular the rotation and mass. Using the NARVAL spectropolarimeter (Observatoire du Pic du Midi, France), it is now possible to measure the large-scale magnetic field of solar analogues (i.e. stars very close to the Sun in the mass-rotation plane, including strict solar twins). From spectropolarimetric time-series, tomographic inversion enables one to reconstruct the field geometry and its progressive distortion under the effect of surface differential rotation. We show the first results obtained on a sample of main-sequence dwarfs, probing masses between 0.7 and 1.4 solar mass and rotation rates between 1 and 3 solar rotation rate.

Cyclical wind variability is an ubiquitous but as yet unexplained feature among OB stars. The O7.5 III(n)((f)) star ξ Persei is the brightest representative of this class on the Northern hemisphere. As its prominent cyclical wind properties vary on a rotational time scale (2 or 4 days) the star has been already for a long time a serious magnetic candidate. As the cause of this enigmatic behavior non-radial pulsations and/or a surface magnetic field are suggested. We present a preliminary report on our attempts to detect a magnetic field in this star with high-resolution measurements obtained with the spectropolarimeter Narval at TBL, France during 2 observing runs of 5 nights in 2006 and 5 nights in 2007. Only upper limits could be obtained, even with the longest possible exposure times. If the star hosts a magnetic field, its surface strength should be less than about 300 G. This would still be enough to disturb the stellar wind significantly. From our new data it seems that the amplitude of the known non-radial pulsations has changed within less than a year, which needs further investigation.

The slowly pulsating B3V star 16 Pegasi was discovered by Hubrig et al. (2006) to be magnetic, based on low-resolution spectropolarimetric observations with FORS1 at the VLT. We have confirmed the presence of a magnetic field with new measurements with the spectropolarimeters Narval at TBL, France and Espadons at CFHT, Hawaii during 2007. The most likely period is about 1.44 d for the modulation of the field, but this could not be firmly established with the available data set. No variability has been found in the UV stellar wind lines. Although the star was reported once to show Hα in emission, there exists at present no confirmation that the star is a Be star.

Studies of stellar magnetism at the pre-main sequence phase can provide important new insights into the detailed physics of the late stages of star formation, and into the observed properties of main sequence stars. This is especially true at intermediate stellar masses, where magnetic fields are strong and globally organised, and therefore most amenable to direct study. This talk reviews recent high-precision ESPaDOnS observations of pre-main sequence Herbig Ae-Be stars, which are yielding qualitatively new information about intermediate-mass stars: the origin and evolution of their magnetic fields, the role of magnetic fields in generating their spectroscopic activity and in mediating accretion in their late formative stages, and the factors influencing their rotational angular momentum.

Accurate observational data are available for the eclipsing double-lined spectroscopic binary system RS Cha, composed of two stars in the pre-main sequence stage of evolution: masses, radii, luminosities and effective temperatures of each component and metallicity of the system. This allows to build pre-main sequence stellar models representing the components of RS Cha and to constrain them in terms of physical ingredients, initial chemical composition and age.

We present stellar models we have calculated using the CESAM stellar evolution code for different sets of physical inputs (opacities, nuclear reaction rates, etc.) and different initial parameters (global metallicity, helium abundance, individual abundances of heavy elements). We discuss their ability to reproduce the observational constraints simultaneously for the two components. We focus on the impact on the models of the chemical mixture adopted and we propose a calibration for the RS Cha system providing an estimate of its age and initial helium abundance.

We report the discovery, using FORS1 at the ESO-VLT and ESPaDOnS at the Canada-France-Hawaii Telescope, of magnetic fields and chemical peculiarities in the Herbig Ae/Be stars HD 72106 and HD 101412. These stars may well represent pre-main sequence progenitors of the magnetic Ap/Bp stars. At the same time, we fail to confirm claims by Hubrig et al. (2004) of the presence of magnetic fields in the Herbig Ae star HD 139614.

We discuss in this paper the new science perspectives that a near infrared (NIR) spectropolarimeter installed on a 4 m class telescope at Dome C in Antartica would offer to the astrophysics community worldwide, in very diverse research fields such as stellar formation, extra solar planets, stellar magnetism and activity, asteroseismology, circumstellar environments, interstellar medium, galactic and extragalactic physics. We also propose an instrument concept with estimated performances, as well as an example 2-step scenario for the construction of this instrument.

We present a short synthetic summary of prospects for stellar astrophysics from Dome C. We conclude that a progressive strategy could be defined, giving access to a 2 m-class telescope, equipped with a highly efficient optical/infrared spectrograph/spectropolarimeter and a wide-field infrared imager, in the 2008 timeframe, then evolving toward a larger telescope with integral field spectroscopic capabilities, and finally to more ambitious instruments, such as interferometers.

HD 34282 has been found to pulsate during a systematic search for short-term photometric variability in Herbig Ae/Be stars with the goal of determining the position and size of the pre-Main Sequence instability strip. Simultaneous Strömgren photometry is used in the frequency analysis, yielding two frequencies with values of $\nu_1 = 79.5$ and $\nu_2 = 71.3$ cycle ${\rm d}^{-1}$. The main period, with a value of 18.12 min, represents the shortest period observed up to now for a $\delta$ Scuti-type pulsator. A preliminary seismic modelling, including instability predictions and rotation effects, has been attempted. Both, Main Sequence and pre-Main Sequence models predict modes in the range of 56 to 82 cycle ${\rm d}^{-1}$ (between 648 and 949 $\mu{\rm Hz}$), corresponding to oscillations of radial order n from 6 to 8. The mode identification is not discriminating due to the large error bars attached to the data, therefore, all possible non-radial and radial modes up to $\ell = 3$ are compatible with the observed oscillations.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Eddington is a space mission for extrasolar planet finding and for asteroseismic observations. It has been selected by ESA as an F2/F3 reserve mission with a potential implementation in 2008-13. Here we describe Eddington's capabilities to detect extrasolar planets, with an emphasis on the detection of habitable planets. Simulations covering the instrumental capabilities of Eddington and the stellar distributions in potential target fields lead to predictions of about 10,000 planets of all sizes and temperatures, and a few tens of terrestrial planets that are potentially habitable. Implications of Eddington for future larger scale missions are briefly discussed.

As potential progenitors of the Ap stars, the pre-main sequence intermediate mass Herbig Ae/Be stars present us with the opportunity to investigate the early history of magnetic fields at these masses. Although we have no direct evidence for the presence of magnetic fields in these stars (except in one case), many clues for such fields have been identified in the past years. They include active phenomena which are often attributed to surface magnetic fields. Rotational modulation of spectral lines formed at the photosphere and in the wind of these stars constitutes yet another indication for the presence of such fields. Future prospects for the detection and mapping of hypothetical magnetic fields in Herbig Ae/Be stars are very encouraging, and in particular spectropolarimetric observations of these stars with instruments like Espadons on CFHT will allow us to test the hypothesis that magnetic fields similar to those found on Ap stars are indeed present in these pre-main sequence objects.

The COROT project, developed in the framework of the CNES small satellite programme with a wide European cooperation, will be launched in 2004. It is dedicated to seismology and the detection of telluric planets. It will perform relative broad-band photometry in visible light, during very long (150 days) observing runs in the same direction. Both programmes are working simultaneously on the same region of the sky. The seismology programme aims at mapping the HR diagram and study in detail 50 targets brighter than 9th magnitude. Another 50 will also be observed with a lower accuracy. The exoplanet programme will search for telluric planets slightly larger than the Earth, in the habitable zone and closer. Its data will also address many seismology problems.

New circular spectropolarimetric observations of the B1 IIIe star β Cep (υsini = 25 km s−1) show a sinusoidally varying weak longitudinal magnetic field (~ 200 G peak-to-peak). The period corresponds to the 12 day period in the stellar wind variations observed in ultraviolet spectral lines. Maximum field occurs at maximum emission in the UV wind lines. This gives compelling evidence for a magnetic-rotator model for this star, with an unambiguous rotation period of 12 days.

The similarity between the Hα emission phases in β Cep and in Be stars suggests that the origin of the Be phenomenon does not have to be rapid rotation: we propose that in β Cep the velocity to bring material in (Keplerian) orbit is provided by the high corotation velocity at the Alfvén radius (~10 R*), whereas in Be stars this is done by the rapid rotation of the surface. In both cases the cause of the emission phases has still to be found. Weak temporary magnetic fields remain the strongest candidate.

A full paper, with results including additional measurements in June and July 1999, will appear in A & A.

COROT is a high precision wide field photometry experiment from space, funded in the framework of the CNES “Petites Missions” program (the PI is A. Baglin). It will observe approximately 30000 objects with mV between 4.5 and 15.5 over long observational periods (up to 150 d), with a time sampling between 1 s and 16 min, a precision of the order of 10−4 per measurement. The scientific objectives are stellar seismology and the search for telluric planets. The instrument and the core program have already been presented in several places. We here focus on a description of the characteristics of the data to be obtained with COROT. The large amount of high quality data collected by COROT will constitute rich material for several research programs beyond the core program as already defined (http://www.astrsp-mrs.fr/www/corot.html). A call for proposal of additional programs will be made during Northern Spring 2000.