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Due to the popularity and flexibility of Minecraft, educators have used this game to develop instructional materials and activities to cultivate student interests in science, technology, engineering and mathematics (STEM). One example of such an initiative is the What-If Hypothetical Implementations in Minecraft (WHIMC) project of the University of Illinois Urbana Champaign. The study reported in this paper describes a WHIMC deployment in the Philippines and the effects this deployment had on student STEM interest. The study used quantitative and qualitative methods to determine the effect of WHIMC on the STEM interest of Filipino students. We performed quantitative analysis of the pre- and post-STEM Interest Questionnaire (SIQ) ratings and Game Experience Questionnaire (GEQ) ratings of the high- and low-performers to determine the effect of using WHIMC in the students’ STEM interest and the difference between the game experience of high- and low-performers, respectively. Qualitative analysis of the answers to the open-ended questions about the attributes of the module was also conducted to determine the relationship between the module attributes and student performance. The analysis of the aggregated SIQ ratings before and after using the WHIMC-based modules revealed only a minimal effect on the STEM interests of the students. However, there was a significant effect in the Choice Actions construct, which implies that students recognize the importance of studying hard if they want to pursue STEM-related careers. Further, the analysis of the overall GEQ of high-performers and low-performers also revealed no significant difference. Although no significant difference was observed in the overall GEQ, high-performers had significantly higher GEQ ratings in the Immersion dimension. This result suggested that high-performers had a more positive, engaging, and enjoyable learning experience. Moreover, the findings on the favorite module attributes suggested that students perform better in the out-of-game assessments when they like all the module attributes. This implies that students must be engaged in the game and learning task aside from being interested in the learning topic to have better assessment scores. The study also showed that open-ended learning environments coupled with tasks that demand exploration, observation, and higher-ordered thinking are demanding even on high-performers.

This research aims to develop a game that accurately simulates situations that would cause cognitive dissonance to the player. Cognitive dissonance is a psychological concept that involves situations of conflicting attitudes, beliefs, or behaviors that result in feelings of mental discomfort. The game is a visual novel with choice-based decisions that will influence the ending of the story. The player will have to make choices that will satisfy either their family for their happiness or their boss for money to spend on their family. In order to assess and measure the player’s cognitive dissonance, the investigators used a modified scale derived from Sweeney, Hausknecht, and Soutar’s research which uses three dimensions to measure dissonance after a major decision. The questions were in the form of a 7-point Likert scale and were integrated within the game itself and presented after the participant makes a major decision. The data was averaged for analysis. Results had shown that the game developed was only able to simulate average levels of cognitive dissonance.

Embodied cognition posits that the development of thinking skills is distributed among mind, senses, and the environment. Research in this field has resulted into the development of applications in different areas including mathematics. This paper reports one part of a larger series of studies on the design and implementation of embodied cognition-based mathematics educational systems. We describe the evaluation of a game called Estimate It!, a wearable-based game for teaching measurement estimation and geometry. Experts were invited to evaluate the game, resulting in a generally positive rating. The game’s collaborative nature, its hands-on way of teaching estimation, and the incorporation of technology were seen as promising points. Infrastructure readiness, classroom control, and adjustment to the new technology were areas of concern.

We present a new technology-based paradigm to support embodied mathematics educational games, using wearable devices in the form of SmartPhones and SmartWatches for math learning, for full classes of students in formal in-school education settings. The Wearable Learning Games Engine is web based infrastructure that enables students to carry one mobile device per child, as they embark on math team-based activities that require physical engagement with the environment. These Wearable Tutors serve as guides and assistants while students manipulate, measure, estimate, discern, discard and find mathematical objects that satisfy specified constraints. Multi-player math games that use this infrastructure have yielded both cognitive and affective benefits. Beyond math game play, the Wearable Games Engine Authoring Tool enables students to create games themselves for other students to play; in this process, students engage in computational thinking and learn about finite-state machines. We present the infrastructure, games, and results for a series of experiments on both game play and game creation.

A theory of cognition called embodied cognition believes that the development of thinking skills is distributed among mind, senses and the environment. Research into this field has resulted into the development of applications in different areas including Mathematics. This paper reports one part of a larger series of studies on the design and implementation of embodied cognition of Mathematics educational systems. We describe the migration and evaluation of a game called "Estimate It", a wearables-based game for teaching measurement estimation and geometry. Teachers and students were invited to evaluate the game. The students found it to be generally fun and expressed their concerns with the game's usability in the smartwatch as a point of improvement. The teachers noted that the game's collaborative nature, its hands-on way of teaching estimation, and the incorporation of technology were seen as promising points. Infrastructure readiness, classroom control and adjustment to the new technology were areas of concern.

Beam asymmetry and differential cross section for the reaction gamma+p->eta+p were measured from production threshold to 1500 MeV photon laboratory energy. The two dominant neutral decay modes of the eta meson, eta->2g and eta->3pi0, were analyzed. The full set of measurements is in good agreement with previously published results. Our data were compared with three models. They all fit satisfactorily the results but their respective resonance contributions are quite different. The possible photoexcitation of a narrow state N(1670) was investigated and no evidence was found., 18 pages, 14 figures, 4 tables Submitted to EPJA

International audience; Meson photoproduction with polarized photons has proved to be a powerful tool to identify contributions of baryon resonances that are not evident in the differential cross-sections. It provides information that are complementary to those extracted using pion-nucleon scattering data. Extensive results have been produced in the past on beam asymmetries by the Graal collaboration for η and $\pi ^0$ on the proton. New results are now available for the same reactions on the quasi-free neutron and for the K+ photoproduction on the proton. Contributions from hitherto undetected baryon resonances may be important to understand the results.

Using a Deuterium target, the GRAAL experiment has collected meson photoproduction data. The data have been analysed in the quasi free regime. The results of the quasi free process on the proton reproduce quite well the results previously obtained with a Hydrogen target. The preliminary results on the quasi free neutron for π0 and η photoproduction are presented and discussed.

Beam asymmetries and hyperon recoil polarizations for the reactions γp → K +Λ and γp → K +Σ0 have been measured from the threshold production to 1500MeV with the GRAAL facility located at the ESRF in Grenoble. These results complement the database for the beam asymmetry, covering for the first time the production threshold region. Recent theoretical analyses are presented for which the beam asymmetry data bring interesting new information and allow to better determine some resonance parameters. Most importantly, these results strengthen the need of a new D13 state around 1900MeV.

Disintegration of C-12 nuclei by tagged photons of 700-1500 MeV energy at the GRAAL facility has been studied by means of the LAGRAN gamma E detector with a wide angular acceptance. The energy and momentum distributions of produced neutrons and protons as well as their multiplicity distributions were measured and compared with corresponding distributions calculated with the RELDIS model based on the intranuclear cascade and Fermi break-up models. It was found that eight fragments are created on average once per about 100 disintegration events, while a complete fragmentation of C-12 into 12 nucleons is observed typically only once per 2000 events. Measured multiplicity distributions of produced fragments are well described by the model. The measured total photoabsorption cross section on C-12 in the same energy range is also reported. (C) 2015 Elsevier B.V. All rights reserved.

We report on new measurements of the beam asymmetry for. photoproduction on protons and neutrons in hydrogen and deuterium targets from the GRAAL Collaboration. The beam asymmetry values are extracted from the reaction threshold (E-gamma = 1.1 GeV in the free nucleon kinematics) up to 1.5 GeV of incoming photon energy. For the first time both the radiative and the three-pion decay channels are simultaneously investigated on the free proton. Results from the two decay channels are in agreement, leading to the world's most precise measurements of the beam asymmetry for omega photoproduction off free protons. First experimental results on the deuteron allow the extraction of the Sigma beam asymmetry on quasifree nucleons. The beam asymmetry angular distributions obtained for the free and the quasifree kinematics show the same behavior, similar to the findings in pseudoscalar meson photoproduction reactions. First results of the beam asymmetry on the quasifree neutrons are presented, showing different strengths and angular distributions from the results on the proton target.

Neutral pion photoproduction has been measured from 550 to 1500 MeV with the GRAAL facility, located at the ESRF in Grenoble. Differential cross-section and beam asymmetry have been measured over a wide angular range. These high-precision data improve significantly the database for the beam asymmetry in the second and third resonance regions covering for the first time the energy domain 1100-1500 MeV. New partial-wave analyses including these data are presented for which the beam asymmetry brings crucial constraints.

We have designed, built and tested a gas threshold Cherenkov counter as prototype for a larger counter foreseen for use in the DIRAC experiment, at CERN. We describe the performances of the counter on a test beam.

We present new Sigma beam asymmetry data for eta meson photoproduction on the proton, using a novel tagged, laser backscattered, linearly polarized photon beam up to 1.1 GeV. The data show large, positive asymmetries, at all incident photon energies. In addition to the S-11(1535) and D-13(1520) resonances necessary to reproduce the cross sections, P-13(1720) and D-15(1675) "four stars" resonances contribute to the Sigma observable, but cannot reproduce the strong forward asymmetries measured at energies higher than 900 MeV.

Compton backscattering gamma ray beams are characterized by a high degree of linear and circular polarization with low unpolarized backgrounds and have proven to provide very precise measurements of polarization observables. Latest results from LEGS and GRAAL experiments on proton and deuteron targets are presented. The Σ beam asymmetry for ω photoproduction has been measured by the GRAAL collaboration for both the ω→π0γ and the ω→π+π−π0 decay channels on the proton target; single and double polarization asymmetries have been provided also for the K photoproduction channel. E and G double polarization asymmetries for single pion photoproduction on the proton and deuteron have been measured at LEGS using a frozen spin HD target.

Monochromatic photon beams have been used to investigate the photofission of 27Al at 69 MeV with plastic nuclear-track detectors. The measured fissility was found to be (5.7+or-1.1)*10-2. This result, along with the available data for 154Sm and 174Yb nuclei taken at the same energy, has been interpreted within the framework of a two-step model for the photofission reaction. According to this model the incoming photon is considered to be absorbed by a neutron-proton pair, and then followed by an evaporation-fission competition for the excited residual nucleus. The measured fissility values are seen to be in satisfactory agreement with the calculated ones, and the predictions from the model are confirmed, specially in the region of light fissioning systems.

An experimental investigation has been carried out on the properties of electromagnetic shower detectors composed of a uniform array of plastic scintil

A study of photofission on natTa, natW and natPt nuclei induced by monochromatic photons of 69 MeV has been performed. The fission yields have been measured by using makrofoil sheets as fission-track detectors, in thick-target 2 pi geometry. The absolute photofission cross sections for the tantalum, tungsten and platinum targets are found, respectively, to be 4.8+or-1.0 mu b, 5.2+or-1.2 mu b and 10+or-2 mu b, and the corresponding deduced fissilities are (3.2+or-0.7)*10-4, (3.4+or-0.8)*10-4 and (6.4+or-1.3)*104-4.

The -beam asymmetry {Sigma} in the photoproduction of negative pions on quasi-free neutrons in a deuterium target was measured at the Grenoble Anneau Accelerateur Laser in the energy interval 700-1500 MeV and over a wide angular range, using polarized and tagged photons. Results are compared with recent partial-wave analyses.

Based on the high sensitivity of Compton scattering off ultra relativistic electrons, the possibility of anisotropies in the speed of light is investigated. The result discussed in this contribution is based on the gamma-ray beam of the ESRF's GRAAL facility (Grenoble, France) and the search for sidereal variations in the energy of the Compton-edge photons. The absence of oscillations yields the two-sided limit of 1.6 x 10^{-14} at 95 % confidence level on a combination of photon and electron coefficients of the minimal Standard Model Extension (mSME). This new constraint provides an improvement over previous bounds by one order of magnitude., Comment: Talk presented at the Fifth Meeting on CPT and Lorentz Symmetry, University of Indiana, June 28-July 2, 2010

The preliminary results obtained by the GRAAL collaboration for the π0π+ photoproduction on the free and quasi-free proton (deuteron) at Eγ = 0.7-1.5 GeV are presented. The total cross section of the γp → π0π+n reaction and invariant mass spectra for the π+π0, π+n and π0n systems are presented in the photon energy range from 0.7 to 1.5 GeV. These results are in good agreement with the 2π-MAID calculations.

The possibility of anisotropies in the speed of light relative to the limiting speed of electrons is considered. The absence of sidereal variations in the energy of Compton-edge photons at the ESRF's GRAAL facility constrains such anisotropies representing the first non-threshold collision-kinematics study of Lorentz violation. When interpreted within the minimal Standard-Model Extension, this result yields the two-sided limit of 1.6 x 10^{-14} at 95% confidence level on a combination of the parity-violating photon and electron coefficients kappa_{o+} and c. This new constraint provides an improvement over previous bounds by one order of magnitude., Comment: 4 pages, 4 figures

International audience; In the framework of investigation of meson photo-production on proton and neutron in a deuterium target at the GRAAL experiment, we present a method to identify the vertex of interaction when in reaction products there are at least two charged particles, by the information provided by the cylindrical multiwire proportional chambers. By this device, we are able to obtain the direction of charged particles that leave the target after a photo-production reaction. For each charged particle, the device provides the coordinates of two points in the laboratory reference system, and the z-axis represents the beam direction. We calculate the trajectory of each charged particle and its cross point, representing the vertex of the reaction.

The $ \Sigma$ beam asymmetry in the photoproduction of neutral pions from quasi-free nucleons in a deuteron target was measured for the first time between 0.60 and 1.50GeV, with the GRAAL polarized and tagged photon beam. The asymmetry values from the quasi-free proton were found equal to the ones extracted from a pure proton target. The asymmetries from quasi-free proton and quasi-free neutron were found equal up to 0.82GeV and substantially different at higher energies. The results are compared with recent partial-wave analyses.

Absolute cross-section measurements for the photofission reactions of $^{197}\mathrm{Au}$, $^{\mathrm{nat}}\mathrm{Pb}$, $^{209}\mathrm{Bi}$, $^{232}\mathrm{Th}$, $^{238}\mathrm{U}$, and $^{235}\mathrm{U}$ nuclei have been performed at an incident photon energy of 69 MeV using monochromatic and polarized photon beams and dielectric fission-track detectors. Nuclear fissility values have been obtained and results are in agreement with those from other laboratories, although in some cases discrepancies are observed between one other. For nuclei in the region of the actinides the fissility result is \ensuremath{\gtrsim}0.4, while for Au, Pb, and Bi nuclei it only is \ensuremath{\sim}${10}^{\mathrm{\ensuremath{-}}3}$--${10}^{\mathrm{\ensuremath{-}}2}$. Results have been interpreted in terms of the primary Levinger's quasideuteron nuclear photoabsorption followed by a mechanism of evaporation-fission competition for the excited nuclei. Shell effects have been taken into account, and they are clearly manifested when fissility is evaluated. The influence of photon polarization on photofission of $^{238}\mathrm{U}$ also has been investigated, and results have shown isotropy in the fragment azimuthal distribution.

We present the first measurements of the gamma-ray beam energy resolution obtained with a new tagging system for the Ladon facility on the storage ring Adone at Frascati. A resolution of the order of 3% in the energy region of 30–80 MeV is obtained in accordance with predictions.

We present the first measurement of the {sigma} beam asymmetry in {eta} photoproduction on the neutron in the photon energy range from threshold to 1.5 GeV. Data have been collected by using the tagged and linearly polarized photon beam and the large solid angle apparatus of the GRAAL facility. Neutron data have been selected among {eta} photoproduction events on the deuteron in the quasi-free kinematics approximation. Proton data, extracted in the same way, are within errors identical to those previously obtained on free protons at the GRAAL facility, except for a few points falling in certain energy bins. This difference is, however, well understood in terms of the Fermi motion of the nucleons in the deuteron. We take the consistency of free and quasi-free proton data as an indication that nuclear effects are negligible also for neutron data. The ETAMAID model, in which a strong coupling of the D{sub 15}(1675) resonance to the {eta}-neutron channel is introduced, can explain the proton data very well, but it cannot describe the beam asymmetry for the neutron.

Backward Compton scattering of laser light against the high-energy electrons circulating in storage rings has produced tagged beams of fully polarized high-energy gamma-rays with an intensity useful for the study of photoreactions. At the ESRF this technique will produce a beam of 1.5 GeV and an intensity of 107 photons per second. We discuss the technical characteristics of such a project and the scientific goals which can be achieved in the study of the electromagnetic transitions of the hardrons and the photoproduction of isobars and strange particles in nucleons and nuclei.

Backward Compton scattering of Laser light against the high energy electrons circulating in storage rings has produced tagged beams of fully polarized high energy gamma rays with an intensity useful for the study of photoreactions. We review the facilities now in operation and those under study and the scientific goals which they can achieve in the study of the electromagnetic transitions of the hadrons and the photoproduction of isobars and strange particles in nucleons and nuclei.

Differential cross sections and beam asymmetries of Compton scattering from He-4 have been measured with linearly polarized photons in the energy range from 206 to 310 MeV . The quality of the results has the potential to provide strong constraints on the understanding of the reaction mechanism in the Delta resonance region. A phenomenological analysis of the experimental results has been performed fitting the data to a multipole expansion including dipole and quadrupole scatterings in the impulse approximation. Results indicate that quadrupole contributions should not be neglected to reproduce the general trend of the experimental results. Comparison with predictions from recent theoretical models shows that important discrepancies exist particularly at backward angles. The additional information carried by the incident photon spin increases the difficulty in achieving a comprehensive description of experimental data.

The GRAAL tagged and polarized γ beam has been operating with a maximum energy of 1100 MeV. For the first time asymmetry results in ν photoproduction were obtained and will be shown. Interesting results have also been obtained for π0 and π+ photo-production, that largely confirm the already existing ones, but also extend in not yet explored angular and energetic regions, especially for backward scattering and energies greater than 900 MeV.

The reaction d(\vec\gamma,np) has been studied using the tagged and polarised LADON gamma ray beam at an energy 30 - 50 MeV to investigate the existence of narrow dibaryonic resonances recently suggested from the experimental measurements in a different laboratory. The beam was obtained by Compton back-scattering of laser light on the electrons of the storage ring ADONE. Photo-neutron yields were measured at five neutron angle \vartheta_n = 22, 55.5, 90, 125 and 157 degrees in the center of mass system.Our results do not support the existence of such resonances., Comment: 16 pages, Latex, 22 figures, 1 table. Nucl. Phys. A to appear

We describe the electromagnetic calorimeter built for the GRAAL apparatus at the ESRF. Its monitoring system is presented in detail. Results from tests and the performance obtained during the first GRAAL experiments are given. The energy calibration accuracy and stability reached is a small fraction of the intrinsic detector resolution., 19 pages, 14 figures, submitted to Nuclear Instruments and Methods

The GRAAL facility produces a highly polarized gamma-ray beam by Compton scattering of laser photons on the electrons of the European Synchrotron Radiation Facility (ESRF) at Grenoble. Preliminary results have been obtained with the LAGRANGE detector showing its excellent performances.

The {sup 28}Si({gamma}{searrow},{ital np}){ital X} reaction has been studied using the Ladon polarized and tagged {gamma}-ray beam, in the energy region between 50 and 75 MeV. The data have been compared with the {ital quasideuteron} mechanism. At the highest photon energy the applied model leads to a satisfactory description of both the unpolarized cross section and beam polarization asymmetry. {copyright} {ital 1996 The American Physical Society.}

We have measured, for the first time, the differential cross section of and the parameter of asymmetry for the reactions 4He ( \(\vec{\gamma }\), γ)4He with linearly polarized photon. The LEGS polarized and tagged gamma-ray beam of Brookhaven National Laboratory has been used in the energy region 180–310 MeV. Data are colleted for five laboratory angles 30°, 45°, 72.5°, 110° and 130°.

We simulate an experiment of ν photoproduction on the nucleon performed with a 4 π BGO electromagnetic calorimeter and a Compton backscattering tagged beam of 1.5 GeV maximum energy to extract information on background suppression and trigger settings. The simulation is possible by the application of an event generator that reproduces the photon-nucleon interaction from the pion threshold up to 4 GeV.

The behaviour of BGO sectors, designed for an electromagnetic calorimeter to be operated at up to 2 GeV, is considered in relation to the different terms that contribute to the overall BGO resolution and to the techniques that can be adopted to reduce them to a minimum. In particular, the measurements of light collection uniformity and energy resolution obtained on a large number of sectors are reported, and their effect on the overall BGO resolution analyzed.

The response to monoenergetic protons of 24 cm long pyramidal BGO sectors, designed for a 4π spectrometer, was measured up to 173 MeV by scattering 200 MeV protons off a polyethylene target. The experimental results are compared with lower energy results and Monte Carlo calculations performed with a modified version of the GEANT code.