Time has come to implement a new way to study the stellar physics from the ground with long-term uninterrupted time series, multi-color photometry, flexibility during observing runs and all for less money. PAIX, Photometer AntarctIca eXtinction, gives new insight to cope with unresolved stellar enigma and stellar oscillation challenges and bears witness, for the first time, to a new technology of the polar instrumental robotization under extreme human and weather conditions in the heart of Antarctica. In fact, the stellar pulsation plays a crucial role in understanding the Universe, however progress is limited by the data accuracy needed to detect numerous modes of oscillations with small amplitudes and by the discontinuous nature of typical ground-based data strings which often introduce ambiguities in the determination of oscillation frequencies. The recent space missions enable to overcome both difficulties, However, the outcome of the space missions shows large gaps in terms of flexibility during the observing runs, the choice of targets, the repair of failures and the inexorable high costs. We present here the new technology from Antarctica, in particular from South Polar Site Dome C that benefits from great image quality and 150 days high time coverage, where the seeing reaches a median value of 1 arcsec during the polar night. We briefly describe the instrumental performances of PAIX, its low-cost commercial components, robotic telescope, multi-band photometer and automatic control, working under harsh weather conditions, even when the temperature reach values as low as -80°C. The polar mission PAIX challenges the space missions and even has more advantages than CoRoT and KEPLER in observing in UBVRI bands and then collecting multicolor light curves simultaneously of several targets. We discuss here the first outcomes of stellar physics from the heart of Antarctica during 10 polar nights and PAIX new results and perspectives on the pulsating stars from Antarctica, especially the connection between the stellar pulsation enigma and the Universe mysteries. Finally, we highlight the impact of PAIX -the robotic Antarctica photometer- on the Astronomy development.
In this invited paper, we implement a new way to study the stellar oscillations, pulsations and their evolutionary properties with long uninterrupted and continuous precision observations over 150 days from the ground, and without the regular interruptions imposed by the earth rotation. PAIX–First Robotic Antarctica Polar Mission– gives a new insight to cope with unresolved stellar enigma and stellar oscillation challenges and offers a great opportunity to benefit from an access to the best astronomical site on Earth –DomeC–. The project is made of low cost commercial components, and achieves astrophysical measurement time-series of stellar physics fields, challenging photometry from space that shows large gaps in terms of flexibility during the observing runs, the choice of targets, the repair of failures and the inexorable high costs. PAIX has yet more advantages than space missions in observing in UBV RI bands and then collecting unprecedented simultaneous multicolor light curves of several targets. We give a brief history of the Astronomy in Antarctica and describe the first polar robotized mission PAIX and the outcome of stellar physics from the heart of Antarctica during several polar nights. We briefly discuss our first results and perspectives on the pulsating stars and its evolution from Antarctica, especially the connection between temporal hydrodynamic phenomena and cyclic modulations. Finally, we highlight the impact of PAIX on the stellar physics study and the remaining challenges to successfully accomplish the Universe explorations under extreme conditions.
The atmospheric turbulence characteristics are important to evaluate the quality of ground-based astronomical
observatory. In order to characterize Ali observatory, Tibet. we have developed a single star Scidar (SSS) system,
which is able to continuously monitor the vertical profiles of both optical turbulence and wind speed. The main
SSS configuration includes a 40cm telescope and a CCD camera for fast sampling the star scintillation pattern.
The SSS technique analyzes the scintillation patterns in real time, by computing the spatial auto-correlation and
at least two cross-correlation images, and retrieves both C2n (h) and V (h) vertical profiles from the ground up to
30km. This paper presents the first turbulence measurements with SSS at Ali observatory in October, 2011. We
have successfully obtained the profiles of optical turbulence and wind speed, as well as the key parameters for
adaptive optics, such as seeing, coherence time, and isoplanatic angle. The favourable results indicate that Ali
observatory can be an excellent astronomical observatory.
Here we present the first photometric extinction measurements in the visible range performed at Dome C in
Antarctica, using PAIX photometer (Photometer AntarctIca eXtinction). It is made with "off the shelf" components,
Audine camera at the focus of Blazhko telescope, a Meade M16 diaphragmed down to 15 cm. For an
exposure time of 60 s without filter, a 10th V-magnitude star is measured with a precision of 1/100 mag. A first
statistics over 16 nights in August 2007 leads to a 0.5 magnitude per air mass extinction, may be due to high
altitude cirrus. This rather simple experiment shows that continuous observations can be performed at Dome C,
allowing high frequency resolution on pulsation and asteroseismology studies. Light curves of one of RR Lyrae
stars: SAra were established. They show the typical trend of a RRLyrae star.
A recent sophisticated photometer, PAIX II, has been installed recently at Dome C during polar summer
2008, with a ST10 XME camera, automatic guiding, auto focusing and Johnson/Bessel UBVRI filter wheels.