An overview of recent results from the MST programme on physics important for the advancement of the reversed field pinch (RFP) as well as for improved understanding of toroidal magnetic confinement more generally is reported. Evidence for the classical confinement of ions in the RFP is provided by analysis of impurity ions and energetic ions created by 1 MW neutral beam injection (NBI). The first appearance of energetic-particle-driven modes by NBI in a RFP plasma is described. MST plasmas robustly access the quasi-single-helicity state that has commonalities to the stellarator and 'snake' formation in tokamaks. In MST the dominant mode grows to 8% of the axisymmetric field strength, while the remaining modes are reduced. Predictive capability for tearing mode behaviour has been improved through nonlinear, 3D, resistive magnetohydrodynamic computation using the measured resistivity profile and Lundquist number, which reproduces the sawtooth cycle dynamics. Experimental evidence and computational analysis indicates two-fluid effects, e.g., Hall physics and gyro-viscosity, are needed to understand the coupling of parallel momentum transport and current profile relaxation. Large Reynolds and Maxwell stresses, plus separately measured kinetic stress, indicate an intricate momentum balance and a possible origin for MST's intrinsic plasma rotation. Gyrokinetic analysis indicates that micro-tearing modes can be unstable at high beta, with a critical gradient for the electron temperature that is larger than for tokamak plasmas by roughly the aspect ratio.

We present new X-ray timing and spectral results on the 8.0 s X-ray pulsar CXOU J010043.1Ϫ721134 from a series of observations using the Chandra X-Ray Observatory. We found a P p (1.88 ‫ע‬ 0.08) # 10 3.9 # 10 spectrum is well fit to an absorbed blackbody of temperature keV with a power-law tail of kT p 0.38 ‫ע‬ 0.02 photon index . We find that the source has an unabsorbed X-ray flux (0.5-10 keV) of ϩ2 G p 2.0 ‫ע‬ 0.6 4 # Ϫ1 ergs cm Ϫ2 s Ϫ1 and a corresponding X-ray luminosity of ∼ ergs s Ϫ1 for a distance of 60 kpc. These Ϫ13 35 10 2 # 10 properties support the classification of CXOU J010043.1Ϫ721134 as the seventh confirmed anomalous X-ray pulsar, the eleventh confirmed magnetar, and the first magnetar to be identified in the Small Magellanic Cloud.

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As nuclear power expands, technical, economic, political, and environmental analyses of nuclear fuel cycles by simulators increase in importance. To date, however, current tools are often fleet-based rather than discrete and restrictively licensed rather than open source. Each of these choices presents a challenge to modeling fidelity, generality, efficiency, robustness, and scientific transparency. The Cyclus nuclear fuel cycle simulator framework and its modeling ecosystem incorporate modern insights from simulation science and software architecture to solve these problems so that challenges in nuclear fuel cycle analysis can be better addressed. A summary of the Cyclus fuel cycle simulator framework and its modeling ecosystem are presented. Additionally, the implementation of each is discussed in the context of motivating challenges in nuclear fuel cycle simulation. Finally, the current capabilities of Cyclus are demonstrated for both open and closed fuel cycles.

We present follow-up optical g 0 , r 0 , and i 0 imaging and spectroscopy of serendipitous X-ray sources detected in six archival Chandra images included in the Chandra Multiwavelength Project (ChaMP). Of the 486 X-ray sources detected between 3  10 À16 and 2  10 À13 (with a median flux of 3  10 À15 ) ergs cm À2 s À1 , we find optical counterparts for 377 (78%), or 335 (68%) counting only unique counterparts. We present spectroscopic classifications for 125 objects, representing 75% of sources with r à < 21 optical counterparts (63% to r à ¼ 22). Of all classified objects, 63 (50%) are broad-line active galactic nuclei (AGNs), which tend to be blue in (g*Àr*) colors. X-ray information efficiently segregates these quasars from stars, which otherwise strongly overlap in these SDSS colors until z > 3:5. We identify 28 sources (22%) as galaxies that show narrow emission lines, while 22 (18%) are absorption line galaxies. Eight galaxies lacking broad-line emission have X-ray luminosities that require they host an AGN (log L X > 43). Half of these have hard X-ray emission suggesting that high gas columns obscure both the X-ray continuum and the broad emission line regions. We find objects in our sample that show signs of X-ray or optical absorption, or both, but with no strong evidence that these properties are coupled. ChaMP's deep X-ray and optical imaging enable multiband selection of small and/or high-redshift groups and clusters. In these six fields we have discovered three new clusters of galaxies, two with z > 0:4, and one with photometric evidence for a similar redshift.