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GHαFaS, a new Fabry-Perot system, is now available at the William Herschel Telescope (WHT). It was mounted, for the first time, at the Nasmyth focus of the 4.2-m WHT on La Palma in 2007 July. Using modern technology, with a spectral resolution of the order R ~ 15,000, and with a seeing-limited spatial resolution, GHαFaS will provide a new look at the Hα-emitting gas over a 4.8' circular field in the nearby universe. Many science programs can be done on a 4.2-m class telescope in world-class seeing conditions with a scanning Fabry-Perot. Not only galaxies but H II regions, planetary nebulae, supernova remnants, and the diffuse interstellar medium are subjects for which unique data can be aquired rapidly. Astronomers from the Laboratoire d'Astrophysique Experimentale (LAE) in Montreal, the Laboratoire d'Astrophysique de Marseille (LAM-OAMP), and the Instituto de Astrofisica de Canarias (IAC), have inaugurated GHαFaS by studying in detail the dynamics of some nearby spiral galaxies. A robust set of state-of-the-art tools for reducing and analyzing the data cubes obtained with GHαFaS has also been developed.

Gas reservoirs, internal or acquired, play an important role in the secular evolution of interacting galaxies, since they are able to enhance/trigger star formation episodes and, probably, feed the activity of active galactic nuclei. Using Fabry‐Perot observations, we have mapped, in the Hα line, the warm (T ≈ 10 4 )g as distribution and the velocity fields of the galaxy members of five interacting, gas-rich galaxy systems. We investigated two M51-like systems (Arp 70 and Arp 74), two systems containing highly disrupted members (WBL 366 and RR 24) and a case of merging in progress (Arp 299, one of the nearest luminous infrared objects). We detected gas motions following the elongated arm/tail of Arp 70b, while in the fainter member of the pair of galaxies, Arp 70a, the gas distribution is off-centred with respect to the stellar isophotes, suggesting an external acquisition. Our kinematic data highlighted noncircular motions in the velocity field of one of the members of Arp 74 (Arp 74a). The two galaxies of the RR 24 system are connected by one tidal tail, through which the kinematically disturbed component RR 24b seems to supply warm gas to RR 24a. In spite of the nearly irregular gas distribution and perturbed morphology, WBL 366a (the star-forming galaxy VV523) and WBL 366b have nearly regular velocity fields. The velocity field in the Arp 299 system is irregular, and gas flow between the two nuclei is detected. The present observations, discussed in the light of model predictions and complementary observations from the literature, suggest that all these systems are still probably in an early phase of the encounter. However, the ionized gas distribution and kinematics are strongly influenced by tidal forces. In particular, cross-fuelling mechanisms between galaxies are in action. In Arp 299 the warm and cold gaseous components show similar kinematic properties, although the cold gas seems to maintain a still better organized motion with respect to the warm gas. Ke yw ords: galaxies: general ‐ galaxies: interactions ‐ galaxies: kinematics and dynamics.

We present the results of imaging and scanning Fabry-Perot interferometry of the cometary nebula GM 3-12 (RNO 124) and Herbig-Haro object HH 376A. The nebula is cone-shaped with the star IRAS 20359+6745 at the apex, straight walls and two probable helical arms. HH 376A is the bow shock structure in the collimated high velocity flow, directed by the axis of the cone nebula, with shock velocity about 70-80 km s - 1 . The spatial and kinematical separation between bow shock and Mach disk in HH 376A was not detected, which makes this object similar to HH 111. The Ha profiles in the vicinity of the source are double peaked. The high velocity component can be attributed to the collimated flow.

Shells are interpreted as debris from interaction/acquisition episodes that occur in a galaxy. We present a study of the warm (T≈ 104 K) gas component in a sample of five shell galaxies belonging to the Malin & Carter compilation. Hα observations have been obtained at the ESO 3.6-m telescope equipped with a CIGALE scanning Fabry–Perot interferometer coupled with a new IPCS camera. Most of our sample galaxies show disturbed/irregular gaseous velocity fields. The gas distribution in NGC 7070A and 7135 shows elongated, asymmetric structure relative to the stellar body. The continuum and line maps for ESO 2400100 show a double nucleus. The nuclei are slightly off-centre with respect to the barycentre of the pair, a deformation that cannot arise from projection effects and that suggests a strong on-going tidal interaction. Kinematics of the stellar and gas component derived for NGC 1553 are similar, although the gas component shows evidence for non-circular motion. In most of our objects the gas and the stellar kinematics appear decoupled, but no rings of gas nor diffuse gas shells are detected. If shell galaxies form through an acquisition/merging event, the general hypothesis according to which the gas in Es is accreted from outside the galaxy is further supported by these data. We speculate concerning shell galaxy evolution using additional information coming from studies of line-strength indices.

[EN] The MOSCAB experiment (Materia OSCura A Bolle) uses the Geyser technique for dark matter search. The results of the first 0.5 kg mass prototype detector using superheated C3F8 liquid were very encouraging, achieving a 5 keV nuclear recoil threshold with high insensitivity to gamma radiation. Additionally, the technique seems to be easily scalable to higher masses for both in terms of complexity and costs, resulting in a very competitive technique for direct dark matter search, especially for the spin dependent case. Here, we report as well in the construction and commissioning of the big detector of 40 kg at the Milano-Bicocca University. The detector, the calibration tests and the evaluation of the background will be presented. Once demonstrated the functionality of the detector, it will be operated at the Gran Sasso National Laboratory in 2015., We acknowledge the financial support of the Spanish Ministerio de Ciencia e Innovación (MICINN) and Ministerio de Economía y Competitividad (MINECO), Grants FPA2012-37528-C02-02, and Consolider MultiDark CSD2009-00064, and of the Generalitat Valenciana, Grants ACOMP/2014/153 and PrometeoII/2014/079.

We present observations of Hα emission of Stephan's Quintet obtained with a scanning Fabry-Perot interferometer and samplings of ~11 km s-1 and ~1''. Our observations show an intragroup arclike feature formed of bright Hα knots and diffuse gas distributed along tidal tails associated with NGC 7318B and possibly also NGC 7318A. New velocities for 23 emitting regions detected along the Hα structure are presented. South of NGC 7318B, along a path covering ~12 h−175 kpc, H II regions with velocities ranging from 5540 to 6700 km s-1 are detected, suggesting that two or more overlapping tidal tails and/or a bow-shock region may have been formed through several interaction events within the group.

For the last ten years faint ionized gas detec- tion has been carried out for elliptical galaxies with suc- cess. The kinematics is essential to understand galaxy gas origin and fate. Here we present a sample of 11 elliptical and lenticular galaxies observed with the \Cigale" scan- ning Perot-Fabry instrument. For each galaxy monochro- matic and velocity map of ionized gas is presented. Geometrical properties such as viewing angles and axis ratios are also derived from observations. Double gaseous components are found in 3 galaxies of our sample, imply- ing an external origin for at least part of the observed gas.

We present results from an ongoing survey dedicated to the ionized gas kinematics of Virgo cluster spiral galaxies using Fabry-Perot interferometry. Our goal is to study the environmental effects on galaxy evolution in the Virgo cluster. We report here on the Halpha distribution map and velocity field of NGC 4438, the prototype of an interacting galaxy near the centre of the cluster., Comment: 2 pages, 1 figure, to be published in "IAU Symposium 217, Recycling intergalactic and interstellar matter", ASP Conf Series

During the summer of 1985, the CIGALE Perot-Fabry scanning interferometer of Marseilles Observatory was installed at the prime focus of the 2.6 m telescope of Byurakan Observatory. The long run (two new moons) was successful and gave matereial for numerous publications.

We present the observations of the BCDG IZW18 performed with a Fabry-Perot interferometer at the CFH 3.6 m telescope and with a multi-pupil spectrograph at the SAO (Russia) 6 m telescope. The morphological structure of the galaxy in emission lines and in continuum, the velocity field of the ionized gas, and [OIII]/H β ratio distribution along the NW component have been investigated. Besides the NW and SE HII components, we find a population of small HII regions. Continuum maps show that the peaks of the stellar light distribution are displaced with respect to the emission lines maxima. the velocity field shows peculiar motions superposed on an approximately regular background implying solid body rotation. Emission line profiles exhibit an asymmetric structure, except for the NW compact component. The [OIII]/H β ratio decreases from the center of the NW component to its edge with the gradient of 1.86 kpc−1.

H α-interferometric observations of the HII-regions Sh2-152 and Sh2-153 are carried out with a high resolution (1 pixel=2.13×2.13 arcsec). They confirm the results on the structure of those formations obtained earlier. Individual radial velocities determined in different points for each of these HII-regions show that the inner motions of ionized matter relative to the exciting stars are, in general, of expanding character. It gives ground to assume that in both these star forming regions the dissipation of matter takes place.

We present Fabry-Perot observations obtained in the frame of the GHASP survey (Gassendi HAlpha survey of SPirals). We have derived the Halpha map, the velocity field and the rotation curve for a new set of 44 galaxies. The data presented in this paper are combined with the data published in the three previous papers providing a total number of 85 of the 96 galaxies observed up to now. This sample of kinematical data has been divided into two groups: isolated (ISO) and softly interacting (SOFT) galaxies. In this paper, the extension of the Halpha discs, the shape of the rotation curves, the kinematical asymmetry and the Tully-Fisher relation have been investigated for both ISO and SOFT galaxies. The Halpha extension is roughly proportional to R25 for ISO as well as for SOFT galaxies. The smallest extensions of the ionized disc are found for ISO galaxies. The inner slope of the rotation curves is found to be correlated with the central concentration of light more clearly than with the type or the kinematical asymmetry, for ISO as well as for SOFT galaxies. The outer slope of the rotation curves increases with the type and with the kinematical asymmetry for ISO galaxies but shows no special trend for SOFT galaxies. No decreasing rotation curve is found for SOFT galaxies. The asymmetry of the rotation curves is correlated with the morphological type, the luminosity, the (B-V) colour and the maximal rotational velocity of galaxies. Our results show that the brightest, the most massive and the reddest galaxies, which are fast rotators, are the least asymmetric, meaning that they are the most efficient with which to average the mass distribution on the whole disc. Asymmetry in the rotation curves seems to be linked with local star formation, betraying disturbances of the gravitational potential. The Tully-Fisher relation has a smaller slope for ISO than for SOFT galaxies.

The results of the scientific cooperation between astronomers of the Byurakan and Marseille observatories on the study of diffuse matter in the Galaxy are presented.Hα-emission is discovered in the direction of h and x Per. Fabry-Perot observations of three HII-regions, Sh2-152, 153, and 106, show the expansion of the diffuse matter relative to the exciting stars. In the Sh2-106 region a probable jet is found. It is shown that in star forming regions the diffuse matter takes part in expansion motions together with stars.

We present results from a Fabry-Perot study of the Hα velocity fields and morphologies of a sample of luminous blue compact galaxies. We estimate masses from photometry and kinematics and show that many of these BCGs are not rotationally supported. Mergers or strong interactions appear to be the triggering mechanism of the extreme starbursts seen in these galaxies.

The Sc galaxy NGC 6181 was observed at the 6m telescope of SAO RAS with the scanning Perot-Fabry interferometer in the H-alpha emission line and at the 1m telescope of SAO RAS in BVRI broadband filters with CCD. Subtraction of the mean circular rotation curve from the two-dimensional velocity field has revealed a ring-like zone with a diameter about of 2 kpc where strong radial gas motions are present. The form of the ring is almost perfectly circular in the plane of the galaxy. It is located closer to the center than the beginning of the well-defined spiral structure, but outside of the central bulge-dominated region. The detected radial velocity reduced to the plane of the galaxy is about 100 km/sec and probably is azimuthally dependent. The very inner region of the galaxy, r < 3 arcsec or 0.5 kpc, shows a turn of the dynamical major axis by about 30 deg. Central continuum isophotes are also twisted which suggests the presence of small nuclear bar., Latex, 9 pages, 6 Postscript figures, 6 GIF figures (+ Fig2. which must be requested by e-mail from olga@sai.msu.su). Accepted for publication in the Astronomy and Astrophysics Supplement Series

In 1990 we began an Hα survey of the Milky Way and the Magellanic clouds at ESO La Silla with a 36 cm telescope. The main goal of this survey is to study in detail complexes of HII regions, as well as the global spiral structure of our Galaxy.

The radial velocities of the ionized gas in the double system of galaxies NGC 2535-36 (Arp 82) have been measured with a scanning Perot-Fabry interferometer and a two-dimensional photon counting system (the CIGALE equipment). Some 3200 velocity points cover the whole galaxy and its companion with a spatial resolution of 1″5 and a velocity accuracy better than 19 km s−1. The redshifts are found to be 4095 km s−1 ± 10 km s−1 for NGC 2535 and 4085 km s−1 ± 10 km s−1 for NGC 2536 (heliocentric radial velocities). Assuming a distance of 41 Mpc the masses are found to be around 3 1010 M⊙ for the main galaxy and 109 M⊙ for its companion.

The velocity field of the nearby Seyfert galaxy Markarian 1040 = NGC 931 has been investigated using the CIGALE instrument [1] at the prime focus of the 6-m Telescope. The Hα- image of the galaxy shows a well developed two-armed spiral pattern (Fig.1a) in the extended (size ≈ 55 kpc, assuming Ho=50 km/s Mpc) gaseous disc. In the velocity field two local velocity maxima at a distance of 20″ from the center are evident relative to the systemic velocity of 4930 ± 5 km/s (Fig.1b) which are located nonsymmetrically to the line of nodes. This results in a decrease of the rotation velocity as a function of radius two times faster than keplerian in the interval between 6 and 12 kpc at the Markarian 1040 rotation curve along the line of nodes (Fig.2). The local maximum at 1 kpc is caused by the compact bulge. The analysis of the velocity field shows strong deviations from an azimuthal symmetry in the mentioned distance interval. Velocities are subtracted from the observed radial velocity field according to an azimuthally symmetric rotation curve defined for each distance interval by the amplitude of the sinus-like dependence on the position angle. It has been found that the rotation curve determined in such a way is in agreement with the rotation curve of an exponential disc with a scale length of 7.5 kpc derived from the galaxy photometry in the continuum.

The velocity field of the giant H II complex NGC 2363 in the SBm galaxy NGC 2366 has been mapped in the forbidden O III 5007 A line using a scanning Fabry-Perot interferometer. The forbidden O III line profiles correspond to symmetrical and single component profiles in most of the nebulae of NGC 2366, except in the bright core of the giant H II NGC 2363 where strong splitting of the line occurs. This splitting is consistent with a bubble 200 pc in diameter expanding with a velocity of 45 km/s. The total kinetic energy of the bubble is 2 x 10 to the 52nd ergs; the kinematic age of the bubble is less than or equal to two million yr. The bubble could be produced by the sole action of combined stellar winds from the central clusters of OB stars. A well-defined sector, 150 pc wide, of the H II complex originating at the bubble shows systematic receding velocities; it is suggested that this region acts as a vent through which gas escape into the halo of the galaxy. Large H-alpha shells are observed in the surroundings of NGC 2363. There is also evidence for a very broad andmore » low-entensity forbidden O III high-velocity component associated with the bubble. 50 refs.« less

The galaxy NGC5128, better known as the powerful radio source Centaurus A, is a puzzling object appearing as an elliptical galaxy crossed by a dense lane of dust and gas. Its structure and evolution are not well understood, although this object is quite near (we shall adopt 5 Mpc following Burbidge and Burbidge1), bright, and has been widely observed in the past few years. We have obtained the first complete velocity field of the ionized gas in NGC5128, with a 10-kms−1 precision, from Perot–Fabry interferometry with the ESO 3.6-m telescope. It shows that the gas is rotating in a thick disk (∼1 kpc thickness), without any evidence of the perturbations expected from the encounter of an elliptical and a spiral galaxy. Our observations favour the hypothesis of the evolution of a spiral galaxy in which the formation of the disk is very late compared with the bulge.

Large aperture telescopes usually have an unavoidably long focal length so that stellar image diameters are often much larger than the resolution of the detector. The detection of extended sources can take advantage of a faster focal ratio and both stellar and extended monochromatic sources can be detected with great sensitivity by using interference filters and a focal reducer, without much loss in resolution. Extragalactic results obtained with the 6 meter telescope at focal ratio f/1 are given as examples.

The bridge of matter connecting the Small Magellanic Cloud (SMC) with the Large Magellanic Cloud (LMC) was first detected thanks to radio observations, and detailed maps of this H I bridge are now available1. Observations of the Magellanic system at Hα wavelength reported by Johnson et al.2 in 1982 seem to show a diffuse Hα emission associated with the H I bridge. As they suggested, it is necessary to confirm this association by obtaining Hα profiles in the direction of this bridge. We did this in February 1984 with the help of a scanning Perot–Fabry interferometer and a photon-counting system at the 1.5-m European Space Observatory (ESO) telescope. The choice of the area to be observed was based on recent observations3 with the Very Wide Field Camera (VWFC) on board Spacelab 1 (November 1983) showing an extension of the SMC towards the LMC at wavelengths of 1,930 and 1,650 A. Detection of Hα emission would check that the ultraviolet emission was emanating from the bridge connecting the two galaxies by showing that the cloud of hot stars giving rise to this ultraviolet emission was ionizing part of the H I bridge.

In 2005, the ANTARES Collaboration deployed and operated at a depth of 2500 m a so-called Mini Instrumentation Line equipped with Optical Modules (MILOM) at the ANTARES site. The various data acquired during the continuous operation from April to December 2005 of the MILOM confirm the satisfactory performance of the Optical Modules, their front-end electronics and readout system, as well as the calibration devices of the detector. The in-situ measurement of the Optical Module time response yields a resolution better than 0.5 ns. The performance of the acoustic positioning system, which enables the spatial reconstruction of the ANTARES detector with a precision of about 10 cm, is verified. These results demonstrate that with the full ANTARES neutrino telescope the design angular resolution of better than $0.3^\circ$ can be realistically achieved., Comment: 18 pages, 12 figures, submitted to Astroparticle Physics