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A primary goal of general education introductory astronomy courses often is to provide students with examples of how science is actually done. Low to nonexistent mathematical prerequisites in some courses can make useful exercises difficult to find, and sometimes very difficult for students, especially if the exercises feature quantitative components. What follows describes an attempt to meet this goal through the use of actual exoplanet data, available online, from the NASA Kepler Mission. The exercise described guides the students through an aspect of scientific investigation that they may otherwise not experience, the handling and analysis of a large set of actual scientific data. [ABSTRACT FROM AUTHOR]

The article presents the author's observation on the development of space program in the U.S. He observes that development of space capabilities during the past decade has opened altogether new vistas to science and to new and powerful technologies. He states that the case for the conquest of space can be classified under three major headings in order of their ultimate contribution to the growth of man's welfare and to the rise of his stature as a civilized being which include science in space, technology in space for advancement of man's civil pursuits and military technologies.

Abstract We are pushing forward with the GRAINE project, a 10-MeV to 100-GeV cosmic γ -ray observation project that uses an emulsion telescope with high angular resolution (0.08° at 1–2 GeV) and polarization sensitivity, and a large aperture area (∼10 m2), by repeating long-duration balloon flights. Through various ground experiments, a balloon-borne experiment in 2011, and a balloon-borne experiment in 2015, the feasibility of cosmic γ -ray observations with a balloon-borne emulsion telescope was pioneered. Through scientific balloon-borne experiments, we can attempt to achieve the following: pioneering polarization observations for high-energy γ rays from pulsars, active galactic nuclei, flares, and γ -ray bursts; direct probing of proton acceleration by π 0 feature detection and approaching an emission mechanism with a spatial structure for supernova remnants; resolving GeV γ -ray excess at the galactic center region; probing new physics beyond the Planck scale by polarization observations with high-energy γ rays propagating over cosmological distances; observing transient sources, e.g. γ -ray bursts and flares, with a high sensitivity, high photon statistics and polarization sensitivity. Developments in scientific balloon-borne experiments are ongoing. [ABSTRACT FROM AUTHOR]

We present a new method for interferometric imaging that is ideal for the large fields of view and compact arrays common in 21 cm cosmology. We first demonstrate the method with the simulations for two very different low-frequency interferometers, the Murchison Widefield Array and the MIT Epoch of Reionization (MITEoR) experiment. We then apply the method to the MITEoR data set collected in 2013 July to obtain the first northern sky map from 128 to 175 MHz at ~2° resolution and find an overall spectral index of -2.73 ± 0.11. The success of this imaging method bodes well for upcoming compact redundant low-frequency arrays such as Hydrogen Epoch of Reionization Array. Both the MITEoR interferometric data and the 150 MHz sky map are available at http://space.mit.edu/home/tegmark/omniscope.html. [ABSTRACT FROM AUTHOR]

The project in process that illustrates below, it is framed in two bigs axis that have been building according with the needs of classroom teaching of physics in Colombia, while the purpose arises is offer conceptual tools in the light of experimentation or the construction of mounts which give reference of eclipses as observable astronomical phenomena. The first of them, historical and cultural with which searches a strengthening to imagination, retaking the worldviews that allowed, essentially, the construction and rise of astronomy. Anda experimental axes from which is approached the question: ¿Why there aren't eclipses every 14 days? And exposes some didactic proposals of experimental order focused to answer, and framed within study of geometry, the optics and celestial mechanics, the latter still being in state of development. [ABSTRACT FROM AUTHOR]

The article focuses on the efforts of the National Aeronautics and Space Administration in the U.S. that are largely concentrated on its manned space flight program, projects Mercury, Gemini and Apollo which hopes to land American explorers on the moon by 1970. Project Mercury is to culminate in a one-day multi-orbital flight in spring 1963, while project Gemini is being developed for two-man earth-orbital missions lasting as long as two weeks and project Apollo's objective is the actual moon flight, landing men on the moon, and returning them safely to earth.

Lunar subsurface sampling is one of the critical technologies in the advancement of space exploration, and a lunar sampler with low weight, small volume, and low power consumption would significantly reduce the cost of space exploration. Thus, this paper proposes a novel miniature lunar sampler which adopts a flexible tape spring as its sampling arm. Compared with existing rigid-arm samplers, the proposed sampler has the merits of very low weight, reduced volume, and little power consumption. The mechanical design is illustrated in detail, the corresponding flexible kinematics model is built by considering flexibility compensation, and the working space of the sampler is depicted. The performance, e.g. the maximum acceleration, the maximum load capacity, and the sampling depth of the flexible arm, is analyzed through experiments, and each limit is established. In addition, the sampling process is demonstrated with the lab-based experiments, and the feasibility of the sampler is verified. [ABSTRACT FROM AUTHOR]

In this study, ignition schemes of the rearwall-expansion cavity in a model scramjet combustor were investigated under inflow conditions of Ma =2.52 with stagnation pressure P 0 =1.6 Mpa and stagnation temperature T 0 =1486 K. It is concluded that under the current experimental condition, it is necessary to apply combined injection setups to achieve a successful ignition process for the rearwall-expansion cavity, including the cavity upstream transverse injection and direct spanwise injection setups. Compared with the cavity direct injection on the rear wall, the cavity direct injection on the leading edge is more beneficial for the formation and propagation of the initial flame and it will performs a more robust combustion in the combustor. For the rearwall-expansion cavity, the combined injection (cavity upstream transverse injection and cavity direct spanwise injection on the leading edge) is an optimized injection setup during the ignition and flame stabilization processes. Due to the configuration characteristics of rearwall-expansion cavity, the wall-pressure distribution in the isolator will not be affected substantially by the heat release in the combustor during a robust combustion process, which is important for the prevention of thermal choking and the unstart of scramjet inlet. [ABSTRACT FROM AUTHOR]

An experimental technique is carried out to demonstrate the measurement of planar Sauter Mean Diameter (SMD or D 32 ) distribution in a liquid centered swirl coaxial injector (LCSC) using simultaneous measurements of Mie scattering, Planar Laser-Induced Fluorescence (PLIF) and Laser diffraction technique (LDT). Here water is used as the test fluid with addition of optimized quantities of the organic dye (Rhodamine 6 g) for PLIF measurements. Experiments are carried out at three experimental conditions with momentum flux ratios of 6.25, 12.14, and 19.95 respectively. Experiments are carried out to study the effect of dye concentration in LDT. LDT (line of sight) is corrected for multiple scattering effects. The SMD distribution obtained from Liquid Sheet Drop Sizing (LSDS) technique is calibrated using LDT (Malvern particle analyzer) that utilizes the principle of diffraction; the results obtained from both the methods are compared and analyzed using the respective histograms. The variations in the distribution of droplet diameter along the axial and radial locations in the spray field are also studied in detail. [ABSTRACT FROM AUTHOR]

Experiments that pursue detection of signals from the Epoch of Reionization (EoR) are relying on spectral smoothness of source spectra at low frequencies. This article empirically explores the effect of foreground spectra on EoR experiments by measuring high-resolution full-polarization spectra for the 586 brightest unresolved sources in one of the Murchison Widefield Array (MWA) EoR fields using 45 h of observation. A novel peeling scheme is used to subtract 2500 sources from the visibilities with ionospheric and beam corrections, resulting in the deepest, confusion-limited MWA image so far. The resulting spectra are found to be affected by instrumental effects, which limit the constraints that can be set on source-intrinsic spectral structure. The sensitivity and power-spectrum of the spectra are analysed, and it is found that the spectra of residuals are dominated by point spread function sidelobes from nearby undeconvolved sources. We release a catalogue describing the spectral parameters for each measured source. [ABSTRACT FROM AUTHOR]

H I intensity mapping is a new observational technique to map fluctuations in the large-scale structure of matter using the 21 cm emission line of atomic hydrogen (H I). Sensitive H I intensity mapping experiments have the potential to detect Baryon Acoustic Oscillations at low redshifts (z ≲ 1) in order to constrain the properties of dark energy. Observations of the H I signal will be contaminated by instrumental noise and, more significantly, by astrophysical foregrounds, such as Galactic synchrotron emission, which is at least four orders of magnitude brighter than the HI signal. Foreground cleaning is recognized as one of the key challenges for future radio astronomy surveys. We study the ability of the Generalized Needlet Internal Linear Combination (GNILC) method to subtract radio foregrounds and to recover the cosmological HI signal for a general H I intensity mapping experiment. The GNILC method is a new technique that uses both frequency and spatial information to separate the components of the observed data. Our results show that the method is robust to the complexity of the foregrounds. For simulated radio observations including H I emission, Galactic synchrotron, Galactic free- free, radio sources, and 0.05mKthermal noise, we find that the GNILC method can reconstruct the H I power spectrum for multipoles 30 < l < 150 with 6 per cent accuracy on 50 per cent of the sky for a redshift z ~ 0.25. [ABSTRACT FROM AUTHOR]

We investigate interstellar extinction curve variations towards ~4 deg² of the inner MilkyWay in VIJKs photometry from the OGLE-III (third phase of the Optical Gravitational Lensing Experiment) and VVV (VISTA Variables in the Via Lactea) surveys, with supporting evidence from diffuse interstellar bands and F435W, F625W photometry. We obtain independent measurements towards ~2000 sightlines of AI, E(V - I), E(I - J) and E(J - Ks), with median precision and accuracy of 2 per cent. We find that the variations in the extinction ratios AI/E(V - I), E(I - J)/E(V - I) and E(J - Ks)/E(V - I) are large (exceeding 20 per cent), significant and positively correlated, as expected. However, both the mean values and the trends in these extinction ratios are drastically shifted from the predictions of Cardelli and Fitzpatrick, regardless of how RV is varied. Furthermore, we demonstrate that variations in the shape of the extinction curve have at least two degrees of freedom, and not one (e.g. RV), which we confirm with a principal component analysis. We derive a median value of (AV/AKs) = 13.44, which is ~60 per cent higher than the 'standard' value. We show that theWesenheit magnitude WI = I - 1.61(I - J) is relatively impervious to extinction curve variations. Given that these extinction curves are linchpins of observational cosmology, and that it is generally assumed that RV variations correctly capture variations in the extinction curve, we argue that systematic errors in the distance ladder from studies of Type Ia supernovae and Cepheids may have been underestimated. Moreover, the reddening maps from the Planck experiment are shown to systematically overestimate dust extinction by ~100 per cent and lack sensitivity to extinction curve variations. [ABSTRACT FROM AUTHOR]

Results of the experiments on model impact vaporization of peridotite, a mineral analogue of stony asteroids, in a nitrogen-methane atmosphere are presented. Nd-glass laser (γ = 1.06 µm) was used for simulation. Pulse energy was ~600-700 J, pulse duration ~10 s, vaporization tempereature ~4000-5000 K. The gaseous medium (96% vol. of N and 4% vol. of CH, P = 1 atm) was a possible analogue of early atmospheres of terrestrial planets and corresponded to the present-day atmosphere composition of Titan, a satellite of Saturn. By means of pyrolytic gas chromatography/mass spectrometry, it is shown that solid condensates obtained in laser experiments contain relatively complex lowand high-molecular weight (kerogen-like) organic compounds. The main products of condensate pyrolysis were benzene and alkyl benzenes (including long-chain ones), unbranched aliphatic hydrocarbons, and various nitrogen-containing compounds (aliphatic and aromatic nitriles and pyrrol). It is shown that the nitrogen-methane atmosphere favors the formation of complex organic compounds upon hypervelocity impacts with the participation of stony bodies even with a small methane content in it. In this process, falling bodies may not contain carbon, hydrogen, and other chemical elements necessary for the formation of the organic matter. In such conditions, a noticeable contribution to the impact-induced synthesis of complex organic substances is probably made by heterogeneous catalytic reactions, in particular, Fischer-Tropsch type reactions. [ABSTRACT FROM AUTHOR]

The Large European Array for Pulsars (LEAP) is an experiment that harvests the collectivepower of Europe's largest radio telescopes in order to increase the sensitivity of high-precision pulsar timing. As part of the ongoing effort of the European Pulsar Timing Array, LEAP aims to go beyond the sensitivity threshold needed to deliver the first direct detection of gravitational waves. The five telescopes presently included in LEAP are the Effelsberg Telescope, the Lovell Telescope at Jodrell Bank, the Nançay Radio Telescope, theSardinia Radio Telescope and the Westerbork Synthesis Radio Telescope. Dual polarization,Nyquist-sampled time series of the incoming radio waves are recorded and processed offline to form the coherent sum, resulting in a tied-array telescope with an effective aperture equivalent to a 195-m diameter circular dish. All observations are performed using a bandwidth of 128 MHz centred at a frequency of 1396 MHz. In this paper, we present the design of the LEAP experiment, the instrumentation, the storage and transfer of data and the processing hardware and software. In particular, we present the software pipeline that was designed to process the Nyquistsampled time series, measure the phase and time delays between each individual telescope and a reference telescope and apply these delays to formthe tied-array coherent addition. The pipeline includes polarization calibration and interference mitigation. We also present the first results from LEAP and demonstrate the resulting increase in sensitivity, which leads to an improvement in the pulse arrival times. [ABSTRACT FROM AUTHOR]

The non-Gaussian nature of the epoch of reionization (EoR) 21-cm signal has a significant impact on the error variance of its power spectrum P(k). We have used a large ensemble of seminumerical simulations and an analytical model to estimate the effect of this non- Gaussianity on the entire error-covariance matrix Cij. Our analytical model shows that Cij has contributions from two sources. One is the usual variance for a Gaussian random field which scales inversely of the number of modes that goes into the estimation of P(k). The other is the trispectrum of the signal. Using the simulated 21-cm Signal Ensemble, an ensemble of the Randomized Signal and Ensembles of Gaussian Random Ensembles we have quantified the effect of the trispectrum on the error variance Cii. We find that its relative contribution is comparable to or larger than that of the Gaussian term for the k range 0.3 ≤ k ≤ 1.0 Mpc-1, and can be even ~200 times larger at k ~ 5Mpc-1. We also establish that the off-diagonal terms of Cij have statistically significant non-zero values which arise purely from the trispectrum. This further signifies that the error in different k modes are not independent. We find a strong correlation between the errors at large k values (≥0.5 Mpc-1), and a weak correlation between the smallest and largest k values. There is also a small anticorrelation between the errors in the smallest and intermediate k values. These results are relevant for the k range that will be probed by the current and upcoming EoR 21-cm experiments. [ABSTRACT FROM AUTHOR]

We measured the bidirectional reflectance in the VIS–NIR spectral range of different surfaces prepared from small-grained spherical water–ice particles over a wide range of incidence and emission geometries, including opposition. We show that coherent backscattering is dominating the opposition effect on fresh sample material, but its contribution decreases when particles become more irregularly shaped and the bulk porosity increases. Strong temporal evolution of the photometric properties of icy samples, caused by particle sintering and resulting in a decrease of backscattering, is shown. The sintering of the ice particles is documented using cryo-SEM micrographs of fresh and evolved samples. To complement the photometric characterization of ices, multiple high albedo laboratory analogs were investigated to study the effects of shape, grain size distribution, wavelength and surface roughness. In addition to the main backscattering peak, the phase curves also display the effect of glory in the case of surfaces of granular surfaces formed by either spherical ice or glass particles. We show that the angular position of the glory can be used to determine accurately the average size of the particles. Reflectance data are fitted by the Hapke photometric model, the Minnaert model and three morphological models. The resulting parameters can be used to reproduce our data and compare them to the results of other laboratory experiments and astronomical observations. [ABSTRACT FROM AUTHOR]

We report periods and JHKL observations for 643 oxygen-rich Mira variables found in two outer bulge fields at b = -7° and l = ±8° and combine these with data on 8057 inner bulge Miras from the Optical Gravitational Lensing Experiment, MACHO and Two Micron All Sky Survey surveys, which are concentrated closer to the Galactic Centre. Distance moduli are estimated for all these stars. Evidence is given showing that the bulge structure is a function of age. The longer period Miras (log P > 2.6, age ~5 Gyr and younger) show clear evidence of a bar structure inclined to the line of sight in both the inner and outer regions. The distribution of the shorter period (metal-rich globular cluster age) Miras appears spheroidal in the outer bulge. In the inner region these old stars are also distributed differently from the younger ones and possibly suggest a more complex structure. These data suggest a distance to the Galactic Centre, R0, of 8.9 kpc with an estimated uncertainty of ~0.4 kpc. The possible effect of helium enrichment on our conclusions is discussed. [ABSTRACT FROM AUTHOR]

Recent measurements of the cosmic microwave background (CMB) B-mode polarization power spectrum by the BICEP2 and POLARBEAR experiments have demonstrated new precision tools for probing fundamental physics. Regardless of origin, the detection of sub-µK CMB polarization represents a technological tour de force. Yet more information may be latent in the CMB's polarization pattern. Because of its tensorial nature, CMB polarization may also reveal parity-violating physics via a detection of cosmic polarization rotation. Although current CMB polarimeters are sensitive enough to measure one degree-level polarization rotation with >5s statistical significance, they lack the ability to differentiate this effect from a systematic instrumental polarization rotation. Here, we motivate the search for cosmic polarization rotation from current CMB data as well as independent radio galaxy and quasar polarization measurements. We argue that an improvement in calibration accuracy would allow the unambiguous measurement of parity- and Lorentz-violating effects. We describe the CalSat space-based polarization calibrator that will provide stringent control of systematic polarization angle calibration uncertainties to 0.05? - an order of magnitude improvement over current CMB polarization calibrators. CalSat-based calibration could be used with current CMB polarimeters searching for B-mode polarization, effectively turning them into probes of cosmic parity violation, 'for free' - i.e. without the need to build dedicated instruments. [ABSTRACT FROM AUTHOR]

We have estimated a metallicity map of the Large Magellanic Cloud (LMC) using the Magellanic Cloud Photometric Survey (MCPS) and Optical Gravitational Lensing Experiment (OGLE III) photometric data. This is a first of its kind map of metallicity up to a radius of 4°-5°, derived using photometric data and calibrated using spectroscopic data of Red Giant Branch (RGB) stars. We identify the RGB in the V, (V - I) colour-magnitude diagrams of small subregions of varying sizes in both data sets. We use the slope of the RGB as an indicator of the average metallicity of a subregion, and calibrate the RGB slope to metallicity using spectroscopic data for field and cluster red giants in selected subregions. The average metallicity of the LMC is found to be [Fe/H] = -0.37 dex (σ[Fe/H] = 0.12) from MCPS data, and [Fe/H] = -0.39 dex (σ[Fe/H] = 0.10) from OGLE III data. The bar is found to be the most metal-rich region of the LMC. Both the data sets suggest a shallow radial metallicity gradient up to a radius of 4 kpc (-0.049 ± 0.002 dex kpc-1 to -0.066 ± 0.006 dex kpc-1). Subregions in which the mean metallicity differs from the surrounding areas do not appear to correlate with previously known features; spectroscopic studies are required in order to assess their physical significance. [ABSTRACT FROM AUTHOR]

The laser-tracked geodetic satellites LAGEOS, LAGEOS II and LARES are currently employed, among other things, to measure the general relativistic Lense–Thirring effect in the gravitomagnetic field of the spinning Earth with the hope of providing a more accurate test of such a prediction of the Einstein’s theory of gravitation than the existing ones. The secular decay a ̇ of the semimajor axes a of such spacecrafts, recently measured in an independent way to a σ a ̇ ≈ 0.1 – 0.01 m yr −1 accuracy level, may indirectly impact the proposed relativistic experiment through its connection with the classical orbital precessions induced by the Earth’s oblateness J 2 . Indeed, the systematic bias due to the current measurement errors σ a ̇ is of the same order of magnitude of, or even larger than, the expected relativistic signal itself; moreover, it grows linearly with the time span T of the analysis. Therefore, the parameter-fitting algorithms must be properly updated in order to suitably cope with such a new source of systematic uncertainty. Otherwise, an improvement of one-two orders of magnitude in measuring the orbital decay of the satellites of the LAGEOS family would be required to reduce this source of systematic uncertainty to a percent fraction of the Lense–Thirring signature. [ABSTRACT FROM AUTHOR]

At the Institute of Space Systems (IRS), experiments have been performed using the high enthalpy, inductively heated plasma generator (IPG) in plasma wind tunnel 3 (PWK3), in order to assess the catalytic behaviour of different materials. Utilising the Upwind Relaxation Algorithm for Non-equilibrium Flows of the University of Stuttgart (URANUS), a methodology for determining catalytic efficiencies by obtaining atomic recombination probabilities γ for high temperature materials, has been developed. This method eliminates the inherent uncertainties produced when using catalytic properties of previously tested materials to infer those of new materials. In this work, eight different candidates for the Thermal Protection System (TPS) of an entry vehicle have been studied, of which six are ceramic materials and the other two are metallic alloys. Thermochemical properties of these specimens are given for surface temperatures between 1000 and 2000 K in pure oxygen and pure nitrogen plasmas. The high enthalpies and relatively low pressure conditions in which these material samples have been tested in PWK3 are relevant for entry applications from Low Earth Orbit (LEO). [ABSTRACT FROM AUTHOR]

We develop a formalism for calculating probabilities for the outcomes of stellar dynamical interactions, based on results from N-body scattering experiments. We focus here on encounters involving up to six particles and calculate probabilities for direct stellar collisions; however our method is in principle valid for larger particle numbers. Our method relies on the binomial theorem, and is applicable to encounters involving any combination of particle radii. We further demonstrate that our base model is valid to within a few per cent for any combination of particle masses, provided the minimum mass ratio is within a factor of a few from unity. This method is particularly suitable for models of collisional systems involving large numbers of stars, such as globular clusters, old open clusters and galactic nuclei, where small subsets of stars may regularly have very close encounters, and the direct integration of all such encounters is computationally expensive. Variations of our method may also be used to treat other encounter outcomes, such as ejections and exchanges. [ABSTRACT FROM AUTHOR]

The article focuses on the clashes between the indigenous people and the modern-day astronomers. It discusses how local indigenous people would be distracted while the astronomers built Thirty Meter Telescope (TMT) and Square Kilometer Array (K), particularly in Hawaii, which may even result in environmental degradation.

We present a code to generate mock observations of 21 cm intensity mapping experiments. The emphasis of the code is on reducing the computational cost of running a full-blown simulation, trading computational time for accuracy. The code can be used to generate independent realizations of the cosmological signal and foregrounds, which are necessary, for instance, in order to obtain realistic forecasts for future intensity mapping experiments. The code is able to reproduce the correct angular and radial clustering pattern for the cosmological signal, including redshift-space distortions, lightcone evolution and bias. Furthermore, it is possible to simulate a variety of foregrounds, including the potentially problematic polarized synchrotron emission. [ABSTRACT FROM AUTHOR]

The Milky Way is expected to host an accreted disc of stars and dark matter. This forms as massive ≳1 : 10 mergers are preferentially dragged towards the disc plane by dynamical friction and then tidally shredded. The accreted disc likely contributes only a tiny fraction of the Milky Way's thin and thick stellar disc. However, it is interesting because (i) its associated ‘dark disc’ has important implications for experiments hoping to detect a dark matter particle in the laboratory; and (ii) the presence or absence of such a disc constrains the merger history of our Galaxy. In this work, we develop a chemodynamical template to hunt for the accreted disc. We apply our template to the high-resolution spectroscopic sample from Ruchti et al., finding at present no evidence for accreted disc stars. Our results are consistent with a quiescent Milky Way with no ≳1 : 10 mergers since the disc formed and a correspondingly light ‘dark disc’. However, we caution that while our method can robustly identify accreted stars, our incomplete stellar sample makes it more challenging to definitively rule them out. Larger unbiased stellar samples will be required for this. [ABSTRACT FROM PUBLISHER]

In this paper we review the main theoretical and experimental achievements in the field of dark matter from the cosmological and astrophysical point of view. We revisit it from the very first surveys of local astrophysical matter, up to the stringent constraints on matter properties, coming from the last release of data on cosmological scales. To bring closer and justify the idea of dark matter, we will go across methods and tools for measuring dark matter characteristics, and in some cases a combination of methods that provide one of the greatest direct proofs for dark matter, such as Bullet cluster. [ABSTRACT FROM AUTHOR]

The Materia OSCura A Bolle (MOSCAB) experiment uses a new technique for Dark Matter search. The Geyser technique is applied to the construction of a prototype detector with a mass of 0.5 kg and the encouraging results are reported here; an accent is placed on a big detector of 40 kg in construction at the Milano Bicocca University and INFN. [ABSTRACT FROM AUTHOR]

In the last decade direct detection Dark Matter (DM) experiments have increased enormously their sensitivity and ton-scale setups have been proposed, especially using germanium and xenon targets with double readout and background discrimination capabilities. In light of this situation, we study the prospects for determining the parameters of Weakly Interacting Massive Particle (WIMP) DM (mass, spin-dependent (SD) and spin-independent (SI) cross-section off nucleons) by combining the results of such experiments in the case of a hypothetical detection. In general, the degeneracy between the SD and SI components of the scattering cross-section can only be removed using targets with different sensitivities to these components. Scintillating bolometers, with particle discrimination capability, very good energy resolution and threshold and a wide choice of target materials, are an excellent tool for a multitarget complementary DM search. We investigate how the simultaneous use of scintillating targets with different SD-SI sensitivities and/or light isotopes (as the case of 2 and ) significantly improves the determination of the WIMP parameters. In order to make the analysis more realistic we include the effect of uncertainties in the halo model and in the spin-dependent nuclear structure functions, as well as the effect of a thermal quenching different from 1. [ABSTRACT FROM AUTHOR]

We study the spin-dependent WIMP scattering off nuclei for a variety of targets of experimental interest. In evaluating the spin structure functions, we have included the recently proposed leading long-range two-body currents in the most important isovector contribution. We show, however, that such effects are essentially independent of the target nucleus and, as a result, they can be treated as a mere renormalization of the effective nucleon cross-section or, equivalently, of the corresponding effective coupling, with reduction factors around 25%. Using these effects in the spin structure functions, we compute the relevant event rates due to the spin for various targets of experimental interest. [ABSTRACT FROM AUTHOR]

In order to reach the sensitivity required to detect gravitational waves, pulsar timing array experiments need to mitigate as much noise as possible in timing data. A dominant amount of noise is likely due to variations in the dispersion measure. To correct for such variations, we develop a statistical method inspired by the maximum likelihood estimator and optimal filtering. Our method consists of two major steps. First, the spectral index and amplitude of dispersion measure variations are measured via a time-domain spectral analysis. Second, the linear optimal filter is constructed based on the model parameters found in the first step, and is used to extract the dispersion measure variation waveforms. Compared to current existing methods, this method has better time resolution for the study of short time-scale dispersion variations, and generally produces smaller errors in waveform estimations. This method can process irregularly sampled data without any interpolation because of its time-domain nature. Furthermore, it offers the possibility to interpolate or extrapolate the waveform estimation to regions where no data are available. Examples using simulated data sets are included for demonstration. [ABSTRACT FROM AUTHOR]

Coronal radio-sounding experiments were carried out using two-way coherent dual-frequency carrier signals of the ESA spacecraft Rosetta (ROS) in 2006. Frequency measurements recorded at both NASA and ESA tracking stations (sample rate: 1 Hz) are analyzed in this work. Spectral analysis of the S-band, X-band, and differential frequency records has shown that the mean frequency fluctuation of each signal can be described by a radial power-law function of the form σ= A( R/R), where i=x,s,sx. The ratio of the coefficients A and A is not the expected theoretical value A/ A= f/ f. This occurs because the X-band fluctuations underlie a two-way propagation mode while the S-band fluctuations are essentially the product of a one-way propagation experiment. Results are compared with similar, but not identical, two-way radio propagation experiments performed during the 1991 solar conjunction of the Ulysses spacecraft. [ABSTRACT FROM AUTHOR]

FAST(The Five-Hundred-Meter Aperture Spherical Radio Telescope) is an under-building radio telescope which will be the largest single dish in the world. Through the study of the central control system, in accordance with the actual operation of the telescope and observation process, this article introduces the physical models for engineers and observers, the central control system architecture design, basic support modules and the necessary interfaces. We simulated observation control process and telescopes monitoring and control process, and took Active Reflector System as a subsystem example to complete the control system design and implementation using EPICS (Experimental Physics and Industrial Control System). The Central control system, with active reflector systems, feed supporting system has been taken to an integration test at Miyun model. In the case of the normal operation of the various sub-systems of the Miyun model by the central control system, a coordinated control is achieved. [ABSTRACT FROM AUTHOR]

The Zooniverse projects turn everyday people into "citizen scientists" who work online with real data to assist scientists in conducting research on a variety of topics related to galaxies, exoplanets, lunar craters, and solar flares, among others. This paper describes our initial study to assess the conceptual knowledge and reasoning abilities of citizen scientists participating in two Zooniverse projects: Galaxy Zoo and Moon Zoo. In order to measure their knowledge and abilities, we developed two new assessment instruments, the Zooniverse Astronomical Concept Survey (ZACS) and the Lunar Cratering Concept Inventory (LCCI). We found that citizen scientists with the highest level of participation in the Galaxy Zoo and Moon Zoo projects also have the highest average correct scores on the items of the ZACS and LCCI. However, the limited nature of the data provided by Zooniverse participants prevents us from being able to evaluate the statistical significance of this finding, and we make no claim about whether there is a causal relationship between one's participation in Galaxy Zoo or Moon Zoo and one's level of conceptual understanding or reasoning ability on the astrophysical topics assessed by the ZACS or the LCCI. Overall, both the ZACS and the LCCI provide Zooniverse's citizen scientists with items that offer a wide range of difficulties. Using the data from the small subset of participants who responded to all items of the ZACS, we found evidence suggesting the ZACS is a reliable instrument (α=0.78), although twenty-one of its forty items appear to have point biserials less than 0.3. The work reported here provides significant insight into the strengths and limitations of various methods for administering assessments to citizen scientists. Researchers who wish to study the knowledge and abilities of citizen scientists in the future should be sure to design their research methods to avoid the pitfalls identified by our initial findings. [ABSTRACT FROM AUTHOR]

Citizen science, in which volunteers work with professional scientists to conduct research, is expanding due to large online datasets. To plan projects, it is important to understand volunteers' motivations for participating. This paper analyzes results from an online survey of nearly 11 000 volunteers in Galaxy Zoo, an astronomy citizen science project. Results show that volunteers' primary motivation is a desire to contribute to scientific research. We encourage other citizen science projects to study the motivations of their volunteers, to see whether and how these results may be generalized to inform the field of citizen science. [ABSTRACT FROM AUTHOR]

Abstract: The low-energy astrophysical S factors of the reaction have been investigated on a 320 kV platform at the Institute of Modern Physics in Lanzhou. The experimental S factor of this reaction shows an interesting sizable drop contrary to any existing theoretical expectations at energies below 200 keV. Such drop has not been fully understood yet and may reflect a novel reaction mechanism. The appearance of an interesting new positive-parity or resonance at is discussed. This study shows the danger of extrapolating experimental data over too large an energy range and demonstrates the need for careful direct experimental studies of reaction cross sections at or near stellar energies. In addition, our new results are discussed in the framework of a SUSY assisted Big-Bang Nucleosynthesis (BBN) model. [Copyright &y& Elsevier]

Abstract: Recently, three reactor neutrino experiments, Daya Bay, Double Chooz and RENO have directly measured the neutrino mixing angle . In this Letter, another important oscillation parameter, effective ( ) is measured using baseline dependence of the reactor neutrino disappearance. A global fit is applied to publicly available data and , are obtained by setting both parameters free. This result is complementary to to be measured by spectrum shape analysis. The measured is consistent with measured by disappearance in MINOS, T2K and atmospheric neutrino experiments within errors. The minimum is small, which means the results from the three reactor neutrino experiments are consistent with each other. [Copyright &y& Elsevier]

Abstract: Several experiments (e.g., Milagro and IceCube) have reported the presence in the sky of regions with significant excess in the arrival direction distributions of Galactic cosmic rays in the TeV-to-PeV energy range. Here we study the possibility that these hotspots are a manifestation of the peculiar nature of these cosmic rays, and of the presence of molecular clouds near the sources. We propose that stable quark matter lumps or so-called strangelets can be emitted in the course of the transition of a neutron star to a more compact astrophysical object. A fraction of these massive particles would lose their charge by spallation or electron capture in molecular clouds located in the immediate neighborhood of their source, and propagate rectilinearly without decaying further, hence inducing anisotropies of the order of the cloud size. With reasonable astrophysical assumptions regarding the neutron star transition rate, strangelet injection and neutralization rates, we can reproduce successfully the observed hotspot characteristics and their distribution in the sky. [Copyright &y& Elsevier]

Abstract: We report in this paper the test results of the Langmuir Probes (LPs) that have been used on several Korean low earth orbit (LEO) satellites since 1999. The probes were designed to measure the electrons in the density range of ∼104 to ∼106/cm3 and temperatures less than ∼104 K, which are the typical characteristics of the upper ionosphere. Careful considerations were given to the probe design to reduce many error sources. For example, a 10 Hz fast voltage sweep was applied to the probe to minimize measurement errors caused by probe contaminations. An electron temperature probe was installed in addition to the LP on the KOMPSAT-1, and the electron temperatures measured simultaneously and independently by the two instruments were compared. The results showed good agreement, which confirms the validity of the LP data obtained from these Korean satellites. [Copyright &y& Elsevier]

We describe goals and principles for the realization the Lyra-B space experiment onboard the International Space Station, which is currently being prepared at the Sternberg Astronomical Institute. The main goal of the experiment is to carry out a high-accuracy, multicolor all-sky survey of stars down to 16-17. The detailed structure of the expected observational data, their possible scientific use, and a number of technical problems are discussed. [ABSTRACT FROM AUTHOR]

The growing field of exoplanetary atmospheric modelling has seen little work on standardized benchmark tests for its models, limiting understanding of the dependence of results on specific models and conditions. With spatially resolved observations as yet difficult to obtain, such a test is invaluable. Although an intercomparison test for models of tidally locked gas giant planets has previously been suggested and carried out, the data provided were limited in terms of comparability. Here, the shallow Portable University Model of the Atmosphere model is subjected to such a test, and detailed statistics produced to facilitate comparison, with both time means and the associated standard deviations displayed, removing the time dependence and providing a measure of the variability. Model runs have been analysed to determine the variability between resolutions, and the effect of resolution on the energy spectra studied. Superrotation is a robust and reproducible feature at all resolutions. [ABSTRACT FROM AUTHOR]

Abstract: Detection of a signal hidden by noise within a time series is an important problem in many astronomical searches, i.e. for light curves containing the contributions of periodic/semi-periodic components due to rotating objects and all other astrophysical time-dependent phenomena. One of the most popular tools for use in such studies is the periodogram, whose use in an astronomical context is often not trivial. The optimal statistical properties of the periodogram are lost in the case of irregular sampling of signals, which is a common situation in astronomical experiments. Parts of these properties are recovered by the Lomb–Scargle (LS) technique, but at the price of theoretical difficulties, that can make its use unclear, and of algorithms that require the development of dedicated software if a fast implementation is necessary. Such problems would be irrelevant if the LS periodogram could be used to significantly improve the results obtained by approximated but simpler techniques. In this work we show that in many astronomical applications, simpler techniques provide results similar to those obtainable with the LS periodogram. The meaning of the Nyquist frequency is also discussed in the case of irregular sampling. [Copyright &y& Elsevier]

In this paper we present the various concepts behind the Astro-WISE Information System. The concepts form a blueprint for general scientific information systems (WISE) which can satisfy a wide and challenging range of requirements for the data dissemination, storage and processing for various fields in science. We review the main features of the information system and its practical implementation. [ABSTRACT FROM AUTHOR]

Understanding the difference between data objects is a major problem especially in a scientific collaboration which allows scientists to collectively reuse data, modify and adapt scripts developed by their peers to process data while publishing the results to a centralized data store. Although data provenance has been significantly studied to address the origins of a data item, it does not however address changes made to the source code. Systems often appear as a large number of modules each containing hundreds of lines of code. It is, in general, not obvious which parts of source code contributed to the change in data object. The paper introduces the Class-Based Object Versioning framework, which overcomes some of the shortcomings of popular versioning systems (e.g. CVS, SVN) in maintaining data and code provenance information in scientific computing environments. The framework automatically identifies and captures useful fine-grained changes in the data and code of scripts that perform scientific experiments so that important information about intermediate stages (i.e. unrecorded changes in experiment parameters and procedures) can be identified and analyzed. The benefits of such a system include querying specific methods and code attributes for data items of interest, finding missing gaps of data lineage and implicit storage of intermediate data. [ABSTRACT FROM AUTHOR]

The paper reviews the Astro-WISE infrastructure and demonstrates that the Astro-WISE Information System provides a Grid itself. We describe the integration of Astro-WISE with an external Grid infrastructure (BiGGrid). The integration is performed on all infrastructural layers (data storage, metadata and processing layers) with Astro-WISE as a 'master' infrastructure. We report the use of the integrated infrastructure for the processing of Astro-WISE hosted data and for the future development of Astro-WISE and Target projects. [ABSTRACT FROM AUTHOR]