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The Study and the Method: The locomotor activity of adult male Sprague-Dawley was automatically recorded in a circular corridor - circadian changes are described as well as the response to the novel situation and its habituation over three hours. Four groups of animals were compared, - those with sham/vehicle operations and those with 6-OHDA dopamine (DA) depleting lesions in - the frontal cortex, the limbic septum, and the ventral tegmental area (VTA - A10). Results: 1/ Lesions of the VTA resulted in increased dark-phase activity, - and a large response to an apomorphine challenge in comparison to other lesion and control groups: 2/ Septal 6-OHDA lesions did not alter locomotion: 3/ After frontal DA depletion there was a small increase of locomotion after the apomorphine challenge, that might reflect increased receptor sensitivity in cortical or sub-cortical areas: (Table 1: HPLC measures of NA, DA and DOPAC for each group in the prefrontal cortex, septum and N. accumbens) Figure 1 illustrates the cumulative photocell counts per hour over 24 hours for the 4 groups:. Figure 2 illustrates the cumulative photocell counts every 10 minutes over 90 minutes post-apomorphine treatment - maximal at 20-30 minutes and habituating over 60 minutes (90 minutes for the VTA group): overall activity VTA >> Frontal > Septal > Controls. Conclusions: Along with correlations found for motor activity with cortical levels of DA and NA, these results are interpreted to support a role for DA, NA and the region of the frontal cortex in modulating locomotion that is primarily mediated by mesolimbic VTA - accumbens - DA activity.

The performance of rats on the conditioned blocking test (CB) of learned inattention was measured in a two-way shuttle avoidance task after sham and dopamine (DA) - depleting lesions of the frontal cortex, the limbic septum, and the ventral tegmental area (VTA - A10). Methods: Animals were trained on two sessions with tone and / or light as conditioned stimuli. One group was trained with both stimuli on both sessions. A second group was trained on the first session with one stimulus and on the second with both stimuli. The blocking of conditioning to the added stimulus (b) was tested by presenting the stimuli (a and b) separately and measuring the blocking ration (avoidance to b/a + b) and response latencies. Results: 1/ No deficits were recorded on tests of sensory and motor ability; 2/ The VTA group alone showed a hyperlocomotor response to apomorphine treatment, - and did not acquire the avoidance response (i.e. did not learn the active avoidance task); 3/ The appearance of blocking in the septally lesioned group was delayed until the end of the 20-trial test session - then it was exaggerated; 4/ Blocking was mildly attenuated in the frontally lesioned group. 5/ Dopamine (DA) levels were depleted by about 80% and noradrenaline (NA) levels by, respectively, 20% and 50% in the frontal and septal regions. Figure 2 illustrates a) the CB impairment in the frontal group relative to sham controls, and b) the late development of "supr-blocking" in septally-damage animals. Figure 3 illustrates the results of the HPLC analysis for NA, DA and DOPAC in frontal cortex, septum, N. accumbens and striatum after 6-OHDA lesions (& vehicle treatment) in the frontal, septal, and VTA areas. Conclusions: The results show that the levels of DA activity, or rather the balance between the activity of DA and NA in frontal and limbic regions can contribute to efficient associative conditioning and / or the normal ability of rats not to attend to a redundant stimulus.

Context. Based on the V-shape search method, two families, Athor and Zita, have been identified within the X-complex population of asteroids located in the inner main belt. The Athor family is ~3 Gyr old while the Zita family could be as old as the Solar System. Both families were found to be capable of delivering near-Earth asteroids (NEAs). Moreover, the Athor family was linked to the low-iron enstatite (EL) meteorites. Aims. The aim of our study is to characterise the spin states of the members of the Athor and Zita collisional families and test whether these members have a spin distribution consistent with a common origin from the break up of their respective family parent asteroids. Methods. To perform this test, our method is based on the well-established asteroid family evolution, which indicates that there should be a statistical predominance of retrograde-rotating asteroids on the inward side of family's V-shape, and prograde-rotating asteroids on the outward side of family's V-shape. To implement the method, we used photometric data from our campaign and the literature in order to reveal the spin states, and hence their rotation sense (prograde or retrograde), of the asteroids belonging to these families. We combined dense and sparse-in-time photometric data in order to construct asteroid rotational light curves; we performed the light curve inversion method to estimate the sidereal period and 3D convex shape along with the spin axis orientation in space of several family member asteroids. Results. We obtained 34 new asteroid models for Athor family members and 17 for Zita family members. Along with the literature and revised models, the Athor family contains 60% (72% considering only the family's core) of retrograde asteroids on the inward side and, conversely, 76% (77% considering only the family's core) of prograde asteroids on the outward side. We also found that the Zita family exhibits 80% of retrograde asteroids on the inward side. In addition, the Zita family presents an equal amount of prograde and retrograde rotators (50% each) on the outward side. However, when we applied Kernel density estimation (KDE), we also found a clear peak for prograde asteroids on the outward side, as expected from the theory. Conclusions. The spin states of these asteroids validate the existence of both families, with the Athor family exhibiting a stronger signature for the presence of retrograde-rotating and prograde-rotating asteroids on the inner and outer side of the family, respectively. Our work provides an independent confirmation and characterisation of these very old families, whose presence and characteristics offer constraints for theories and models of the Solar System's evolution. [ABSTRACT FROM AUTHOR]

We present relative astrometric and photometric measurements of visual double stars made in 2013–2015, with PISCO2 installed at the 76‐cm refractor of Côte d'Azur Observatory in Nice (France). Our observing list contains orbital couples as well as double stars whose motion is still uncertain. Most of the observations were done in 2015, but some other observations of wide couples were done in 2013–2014 (0.3% of the total of the observations). Three different techniques were used for obtaining measurements: lucky imaging, speckle interferometry and the direct vector autocorrelation method. From our observations of 2837 multiple stars, we obtained 5182 new measurements with angular separations in the range of 0″$$ {}^{{\prime\prime} } $$.1–32″$$ {}^{{\prime\prime} } $$ and an average accuracy of 0″.018$$ {0}^{{\prime\prime} }.018 $$. The mean error on the position angles is 0°.8. Most of the position angles were determined without the usual 180° ambiguity with the application of the direct vector autocorrelation technique and/or by inspection of the Lucky images or the long integration files. We managed to routinely monitor faint systems (mV≈9−11$$ {m}_V\approx 9-11 $$) with large magnitude difference (up to ΔmV≈4.5$$ \Delta {m}_V\approx 4.5 $$). We have thus been able to measure 21 systems containing red dwarf stars that had been poorly monitored since their discovery, from which we estimated the stellar masses thanks to Gaia measurements. We also measured the magnitude difference of the two components of 1079 double stars with an estimated error of 0.2 mag. Except for a few objects that are discussed, our measurements are in good agreement with the ephemerides computed with published orbital elements, even for the double stars whose separation is smaller than the diffraction limit. Thanks to good seeing images and with the use of high‐contrast numerical filters, we have also been able to obtain 196 measurements with an angular separation smaller than the diffraction limit of our instrumentation, and consistent with those obtained with larger telescopes. We also report measurements of the 164 new double stars that we found in the files obtained during the observations. Finally, from a study of the DR3 Gaia release, it is shown that all the objects of the Tycho Double Star Catalog that we did not resolve in 2015 are probably false detections by Tycho. [ABSTRACT FROM AUTHOR]

We present new speckle measurements of the position of Linus, the satellite of the asteroid (22) Kalliope, obtained at the 1 m Centre Pédagogique Planètes et Univers -Epsilon telescope on the Plateau de Calern , France. Observations were made in the visible domain with the speckle camera Pupil Interferometry Speckle camera and COronagraph. We obtained 122 measurements in February–March 2022 and April 2023, with a mean uncertainty close to 10 milliarcsec on the angular separation. [ABSTRACT FROM AUTHOR]

In this paper, we report on spatial intensity interferometry measurements within the  Hα line on two stars: the Luminous Blue Variable supergiant P Cygni and the late-type B supergiant Rigel. The experimental setup was upgraded to allow simultaneous measurement of two polarization channels, instead of one in our previous setup, and the zero baseline correlation function on-sky to validate independent estimates obtained from the stellar spectrum and the instrumental spectral throughput. Combined with simultaneous spectra measurements and based on radiative transfer models calculated with the code CMFGEN, we were able to fit our measured visibility curves to extract the stellar distances. Our distance determinations for both P Cygni (1.61 ± 0.18 kpc) and Rigel (0.26 ± 0.02 kpc) agree very well with the values provided by astrometry with the Gaia and Hipparcos missions, respectively. This result for Rigel was obtained by adopting a stellar luminosity of L ⋆ = 123 000 L⊙, which is reported in the literature as being consistent with the Hipparcos distance to Rigel. However, due to the lack of consensus on Rigel's luminosity, we also explore how the adoption of the stellar luminosity in our models affects our distance determination for Rigel. In conclusion, we support, in an independent way, the distance to Rigel as the one provided by the Hipparcos mission, when taking the luminosity of 123 000 L⊙ at face value. This study is the first successful step towards extending the application of the Wind Momentum Luminosity Relation method for distance calibration from an LBV supergiant to a more normal late-type B supergiant. [ABSTRACT FROM AUTHOR]

Primary cutaneous T-cell lymphomas showing Gamma-Delta ( ) phenotype and predominantly Epidermotropic pattern are clinicopathologically distinct from classic primary cutaneous T-cell lymphomas. The last patient (n°4) experienced an ENT relapse (palate ulceration) after 42 months of remission under methotrexate. Cutaneous gamma delta T-cell lymphomas (CGDTCL) are rare lymphomas representing <1% of all cutaneous lymphomas, globally associated with a decreased overall survival.1,2 CGDTCL are a defined entity of the 2018 EORTC-WHO classification, most often presenting as nodules or infiltrated plaques, but mycosis fungoides-like3 and pagetoid reticulosis-like presentations have also been reported.4 The prognosis is generally poor.5,6 A few indolent cases have been reported.1,7-9 The clinical presentation of such indolent PCGDTCL has been poorly described. [Extracted from the article]

The ASTEP project (Antarctic Search for Transiting ExoPlanets), aims at testing the quality of the Dome C site in Antarctica for photometry in the visible, as well as detecting and characterizing transiting exoplanets. A dedicated telescope, ASTEP400, has been developped and installed at Concordia. The first campaign took place during the winter 2010, and the telescope functionned nominally during all the winter. A first analysis of the data leads to a precision of 189 and 205 ppm for WASP-19 and WASP-18 respectively, for continuous observations during 1 month. This shows that extremely high precision photometry is achievable from Dome C.

We present intensity interferometry of the luminous blue variable P Cyg in the light of its H α emission performed with 1 m-class telescopes. We compare the measured visibility points to synthesized interferometric data based on the CMFGEN physical modelling of a high-resolution spectrum of P Cyg recorded almost simultaneously with our interferometry data. Tuning the stellar parameters of P Cyg and its H α linear diameter, we estimate the distance of P Cyg as 1.56 ± 0.25 kpc, which is compatible within 1σ with 1.36 ± 0.24 kpc reported by the Gaia DR2 catalogue of parallaxes recently published. Both the values are significantly smaller than the canonic value of 1.80 ± 0.10 kpc usually adopted in literature. Our method used to calibrate the distance of P Cyg can apply to very massive and luminous stars both in our Galaxy and neighbouring galaxies, and can improve the so-called wind momentum–luminosity relation that potentially applies to calibrate cosmological candles in the local Universe. [ABSTRACT FROM AUTHOR]

Summary: The erythrodermic ulcerated form of mycosis fungoides (MF) is exceptional, and treatment of refractory cases is challenging. Brentuximab vedotin (BV) is a monoclonal antibody combined with monomethyl auristatin E, recently approved for the treatment of refractory CD30+ cutaneous T‐cell lymphoma. We report a case of refractory MF in a 56‐year‐old man with a long history of large‐plaque parapsoriasis, as revealed by psoriasiform erythroderma, treated initially with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) polychemotherapy, inducing a 2‐year complete response. After relapse, interferon and gemcitabine were unsuccessful. Finally, treatment with BV was decided upon, despite the absence of CD30 expression. After three infusions of BV 1·8 mg kg−1, we achieved a complete and stable response, allowing an allogeneic stem cell transplant. The patient is still in complete remission, 19 months after the graft. This case illustrates the possibility of using BV in refractory CD30–MF as a salvage therapy. What's already known about this topic? The efficiency of brentuximab vedotin in refractory CD30+ cutaneous T‐cell lymphoma is well established.Erythrodermic forms of MF are challenging to treat, and allogeneic stem cell transplant is sometimes required. What does this study add? This psoriasiform, ulcerated and erythrodermic clinical presentation of MF is exceptional, and the response to brentuximab vedotin, despite the absence of CD30 expression on skin biopsy, allowed us to perform an allogeneic stem cell transplant, inducing long‐term complete remission. Linked Comment: Sun and Wang. Br J Dermatol 2019; 180:1300–1301. [ABSTRACT FROM AUTHOR]

The so-called Barbarian asteroids [from the name of the prototype of this class, asteroid (234) Barbara] are extremely interesting objects because they might be the survivors of a very early generation of planetesimals. We have identified in the past the first case of an asteroid family (the Watsonia family) whose members are Barbarians, all issued from the collisional disruption of a sizeable parent body. Here we report on the identification of another family, called after the name of its biggest member, asteroid (606) Brangäne, consisting of objects displaying the polarimetric properties characterizing the Barbarian behaviour. This is the first recognized case of a swarm of small Barbarians issued from a quite recent cratering event. [ABSTRACT FROM AUTHOR]

Context. Dome C in Antarctica is a promising site for photometric observations thanks to the continuous night during the Antarctic winter and favorable weather conditions. Aims.We developed instruments to assess the quality of this site for photometry in the visible and to detect and characterize variable objects through the Antarctic Search for Transiting ExoPlanets (ASTEP) project. Methods. Here, we present the full analysis of four winters of data collected with ASTEP South, a 10 cm refractor pointing continuously toward the celestial south pole. We improved the instrument over the years and developed specific data reduction methods. Results. We achieved nearly continuous observations over the winters. We measure an average sky background of 20 mag arcsec−2 in the 579–642 nm bandpass. We built the lightcurves of 6000 stars and developed a model to infer the photometric quality of Dome C from the lightcurves themselves. The weather is photometric 67.1 ± 4.2% of the time and veiled 21.8 ± 2.0% of the time. The remaining time corresponds to poor quality data or winter storms. We analyzed the lightcurves of σ Oct and HD 184465 and find that the amplitude of their main frequency varies by a factor of 3.5 and 6.7 over the four years, respectively. We also identify 34 new variable stars and eight new eclipsing binaries with periods ranging from 0.17 to 81 days. Conclusion. The phase coverage that we achieved with ASTEP South is exceptional for a ground-based instrument and the data quality enables the detection and study of variable objects. These results demonstrate the high quality of Dome C for photometry in the visible and for time series observations in general. [ABSTRACT FROM AUTHOR]

The present article reports on the first spatial intensity interferometry measurements on stars since the observations at Narrabri Observatory by Hanbury Brown et al. in the 1970s. Taking advantage of the progresses in recent years on photon-counting detectors and fast electronics, we were able to measure the zero-time delay intensity correlation g (2)(τ = 0, r) between the light collected by two 1-m optical telescopes separated by 15 m. Using two marginally resolved stars (α Lyr and β Ori) with R magnitudes of 0.01 and 0.13, respectively, we demonstrate that 4-h correlation exposures provide reliable visibilities, whilst a significant loss of contrast is found on α Aur, in agreement with its binary-star nature. [ABSTRACT FROM AUTHOR]

Asteroid (3200) Phaethon is a Near-Earth Apollo asteroid with an unusual orbit that brings it closer to the Sun than any other known asteroid. Its last close approach to the Earth was in 2017 mid-December and the next one will be on 2026 October. Previous rotationally time-resolved spectroscopy of Phaethon showed that its spectral slope is slightly bluish, in agreement with its B/F taxonomic classification, but at some rotational phases, it changes to slightly reddish. Motivated by this result, we performed time-resolved imaging polarimetry of Phaethon during its recent close approach to the Earth. Phaethon has a spin period of 3.604 h, and we found a variation of the linear polarization with rotation. This seems to be a rare case in which such variation is unambiguously found, also a consequence of its fairly large amplitude. Combining this new information with the brightness and colour variation as well as previously reported results from Arecibo radar observations, we conclude that there is no variation of the mineralogy across the surface of Phaeton. However, the observed change in the linear polarization may be related to differences in the thickness of the surface regolith in different areas or local topographic features. [ABSTRACT FROM AUTHOR]

A multicolour phase-polarization curve of asteroid (3200) Phaethon has been obtained during the 2017 December apparition by merging measurements taken at the observing station of Calern (France) and at the Rozhen observatory (Bulgaria). All the observations were obtained in the positive polarization branch, the phase angle ranging from 36° to 116°. The measured values of linear polarization are among the highest ever observed for a Solar system body. The covered interval of phase angle was not sufficiently extended to derive a firm determination of the P max parameter, but this appears to occur at a phase angle around 130° and reaches more than 45 per cent of linear polarization. Phaethon is the parent body of the Geminid meteor shower, and the real physical nature of this object (asteroid or comet) has been a long-debated subject. Our polarimetric measurements seem to support the asteroid hypothesis with a phase-polarization curve similar to the asteroid (2) Pallas, but further observations at smaller phase angles are needed to draw definitive conclusions. [ABSTRACT FROM AUTHOR]

We report the first intensity correlationmeasured with starlight since the historical experiments of Hanbury Brown and Twiss. The photon bunching g(2)(τ , r = 0), obtained in the photoncounting regime, was measured for three bright stars: α Boo, α CMi and β Gem. The light was collected at the focal plane of a 1-m optical telescope, transported by a multi-mode optical fibre, split into two avalanche photodiodes and correlated digitally in real time. For total exposure times of a few hours, we obtained contrast values around 2 × 10-3, in agreement with the expectation for chaotic sources, given the optical and electronic bandwidths of our set-up. Comparing our results with the measurement of Hanbury Brown et al. for α CMi, we argue for the timely opportunity to extend our experiments to measuring the spatial correlation function over existing and/or foreseen arrays of optical telescopes diluted over several kilometres. This would enable microarcsec long-baseline interferometry in the optical, especially in the visible wavelengths, with a limiting magnitude of 10. [ABSTRACT FROM AUTHOR]

Context: Polarimetry is a powerful remote sensing tool to characterise solar system planets and, potentially, to detect and characterise exoplanets. The linear polarisation of a planet as a function of wavelength and phase angle is sensitive to the cloud and haze particle properties in planetary atmospheres, as well as to their altitudes and optical thicknesses. Aims: We present for the first time polarimetric signals of Jupiter mapped over the entire disk, showing features such as contrasts between the belts and zones, the polar regions, and the Great Red Spot. We investigate the use of these maps for atmospheric characterisation and discuss the potential application of polarimetry to the study of the atmospheres of exoplanets. Methods: We have obtained polarimetric images of Jupiter, in the B, V, and R filters, over a phase angle range of α = 4°-10.5°. In addition, we have obtained two spectropolarimetric datasets, over the wavelength range 500-850 nm. An atmospheric model was sought for all of the datasets, which was consistent with the observed behaviour over the wavelength and phase angle range. Results: The polarimetric maps show clear latitudinal structure, with increasing polarisation towards the polar regions, in all filters. The spectropolarimetric datasets show a decrease in polarisation as a function of wavelength along with changes in the polarisation in methane absorption bands. A model fit was achieved by varying the cloud height and haze optical thickness; this can roughly produce the variation across latitude for the V and R filters, but not for the B filter data. The same model particles are also able to produce a close fit to the spectropolarimetric data. The atmosphere of Jupiter is known to be complex in structure, and data taken at intermediate phase angles (unreachable for Earth-based telescopes) seems essential for a complete characterisation of the atmospheric constituents. Because exoplanets orbit other stars, they are observable at intermediate phase angles and thus promise to be better targets for Earth-based polarimetry. [ABSTRACT FROM AUTHOR]

A new polarimeter based on the wedged double Wollaston concept has been built at the Torino Observatory and installed on a 1-m telescope at the Calern observing station of the Observatoire de la Côte d'Azur, France. Its main purpose is to carry out a polarimetric survey of minor Solar system objects, which is called the Calern Asteroid Polarimetric Survey. In this paper, we describe the new Torino polarimeter and the results of preliminary scientific validation tests. A number of standard stars with known polarization states, as well as a number of asteroids for which the polarimetric properties are known, have been observed in order to assess the instrument's accuracy. The instrumental polarization has been found to be stable within a few 10-4 units. A total of 124 new polarimetric observation of 78 asteroids are presented. In the case of asteroids already observed in the past, the new data are in agreement with available phase-polarization curves with error bars smaller than most previously published data. We also present data for 21 asteroids that have never been observed before in polarimetry. [ABSTRACT FROM AUTHOR]

The article offers information related to primary cutaneous follicle center B-cell lymphoma (PCFCL). Topics discussed include occurrence of the disease with erythematous papules, plaques and tumors that predominate on the head, neck and upper trunk; CD10 and Ki67 staining's were performed on paraffin embedded biopsies. It notes that the patients who had recurrent disease relapsed after treatment with rituximab, radiation therapy, and topical steroids.

ASTEP 400, the main instrument of the ASTEP (Antarctica Search for Transiting ExoPlanets) programme, is a 40 cm telescope, designed to withstand the harsh conditions in Antarctica, achieving a photometric accuracy of a fraction of millimagnitude on hourly time-scales for planet-hosting southern bright (R ~ 12 mag) stars. We review the performances of this instrument, describe its operating conditions, and present results from the analysis of observations obtained during its first three years (2010–2012) of operation, before its repatriation in 2014. During this time, we observed a total of 22 stellar fields (1° × 1° field of view). Each field, in which we measured stars up to magnitude R = 18 mag, was observed continuously during ~ 7 to ~ 30 d. More than 200 000 frames were recorded and 310 000 stars processed, using an implementation of the optimal image subtraction photometry algorithm. We found 43 planetary transit candidates. 20 of these candidates were observed using spectroscopic follow-ups including four targets classified as good planet candidates. Our results demonstrate that accurate near-continuous photometric observations are achievable from the Concordia station at Dome C in Antarctica, even if we were not able to reach the nominal photometric precision of the instrument. We conducted a correlation analysis between the rms noise and a large number of external parameters and found that source of the ~1 mmag correlated noise is not obvious and does not depend on a single parameter. However, our analysis provided some hints and guidance to increase the photometric accuracy of the instrument. These improvements should equip any future telescope operating in Antarctica. [ABSTRACT FROM AUTHOR]

Dear Editor, The early diagnosis of cutaneous T-cell lymphoma (CTCL) may be challenging and based on a combination of clinical, biological, histological and molecular criteria.1 High-throughput sequencing (HTS) of the T-cell receptor genes allows identification and quantification of each T-cell clone through the recognition of CDR3 (complementarity-determining region 3) sequences in tissue samples.2 It can be used for the sensitive monitoring of CTCL minimal residual disease.3,4 It has also been shown that tumour clone frequency (TCF, defined as the frequency of the top T-cell clone as the percentage of all T cells in a skin sample) > 25% was an independent prognostic factor of progression-free and overall survival in early-stage mycosis fungoides (MF),5 and that it correlated with the degree of skin involvement in CTCL.6 Some studies suggested that HTS was more sensitive than standard polymerase chain reaction (PCR) for the identification of a dominant T-cell clone in early MF,2,7 whereas others found a similar sensitivity.8 However, the interpretation of HTS clonality data remains subjective, as internationally validated thresholds for the definition of a dominant T-cell clone by HTS have not been published. Diagnostic performance of high-throughput sequencing of the T-cell receptor beta gene for the diagnosis of cutaneous T-cell lymphoma Both techniques identified an identical T-cell clone in all blood-skin couples of samples, except in one blood sample in which a dominant T-cell clone was identified by HTS I TRB i , identical to the skin, but no dominant T-cell clone was identified by PCR. [Extracted from the article]

Photometric light-curve inversion of minor planets has proven to produce a unique model solution only under the hypothesis that the asteroid is convex. However, it was suggested that the resulting shape model, for the case of non-convex asteroids, is the convex-hull of the true asteroid non-convex shape. While a convex shape is already useful to provide the overall aspect of the target, much information about real shapes is missed, as we know that asteroids are very irregular. It is a commonly accepted evidence that large flat areas sometimes appearing on shapes derived from light curves correspond to concave areas, but this information has not been further explored and exploited so far. We present in this paper a method that allows to predict the presence of concavities from such flat regions. This method analyses the distribution of the local normals to the facets composing shape models to predict the presence of abnormally large flat surfaces. In order to test our approach, we consider here its application to a large family of synthetic asteroid shapes, and to real asteroids with large-scale concavities, whose detailed shape is known by other kinds of observations (radar and spacecraft encounters). The method that we propose has proven to be reliable and capable of providing a qualitative indication of the relevance of concavities on well-constrained asteroid shapes derived from purely photometric data sets. [ABSTRACT FROM AUTHOR]

ASTEP (Antarctic Search for Transiting Exo Planets) is a research program funded mainly by French ANR grants and by the French Polar Institute (IPEV), dedicated to the photometric study of exoplanetary transits from Antarctica.The preliminary “pathfinder” instrument ASTEP–South is described in another communication (Crouzet et al., these proceedings), and we focus in this presentation on the main instrument of the ASTEP program: “ASTEP–400”, a 40 cm robotized and thermally-controlled photometric telescope operated from the French-Italian Concordia station (Dome C, Antarctica).ASTEP–400 has been installed at Concordia during the 2009-2010 summer campaign. Since, the telescope has been operated in nominal conditions during 2010 and 2011 winters, and the 2012 winterover is presently in progress. Data from the first two winter campaigns are available and processed. We give a description of the ASTEP–400 telescope from the mechanical, optical and thermal point of view. Control and software issues are also addressed. We end with a discussion of some astronomical results obtained with ASTEP–400. [ABSTRACT FROM PUBLISHER]

The ASTEP project aims at detecting and characterizing transiting planets from Dome C, Antarctica, and qualifying this site for photometry in the visible. The first phase of the project, ASTEP South, is a fixed 10 cm diameter instrument pointing continuously towards the celestial South Pole. Observations were made almost continuously during 4 winters, from 2008 to 2011. The point-to-point RMS of 1-day photometric lightcurves can be explained by a combination of expected statistical noises, dominated by the photon noise up to magnitude 14. This RMS is large, from 2.5 mmag at R = 8 to 6% at R = 14, because of the small size of ASTEP South and the short exposure time (30 s). Statistical noises should be considerably reduced using the large amount of collected data. A 9.9-day period eclipsing binary is detected, with a magnitude R = 9.85. The 2-season lightcurve folded in phase and binned into 1,000 points has a RMS of 1.09 mmag, for an expected photon noise of 0.29 mmag. The use of the 4 seasons of data with a better detrending algorithm should yield a sub-millimagnitude precision for this folded lightcurve. Radial velocity follow-up observations reveal a F-M binary system. The detection of this 9.9-day period system with a small instrument such as ASTEP South and the precision of the folded lightcurve show the quality of Dome C for continuous photometric observations, and its potential for the detection of planets with orbital periods longer than those usually detected from the ground. [ABSTRACT FROM PUBLISHER]