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A recent DIII-D experiment investigating the impact of electron cyclotron heating (ECH) on neutral beam driven reversed shear Alfvén eigenmode (RSAE) activity is presented. The experiment includes variations of ECH injection location and timing, current ramp rate, beam injection geometry (on/off-axis), and neutral beam power. Essentially all variations carried out in this experiment were observed to change the impact of ECH on AE activity significantly. In some cases, RSAEs were observed to be enhanced with ECH near the off-axis minimum in magnetic safety factor (), in contrast to the original DIII-D experiments where the modes were absent when ECH was deposited near . It is found that during intervals when the geodesic acoustic mode (GAM) frequency at is elevated and the calculated RSAE minimum frequency, including contributions from thermal plasma gradients, is very near or above the nominal TAE frequency (f TAE), RSAE activity is not observed or RSAEs with a much reduced frequency sweep range are found. This condition is primarily brought about by ECH modification of the local electron temperature (T e) which can raise both the local T e at as well as its gradient. A q-evolution model that incorporates this reduction in RSAE frequency sweep range is in agreement with the observed spectra and appears to capture the relative balance of TAE or RSAE-like modes throughout the current ramp phase of over 38 DIII-D discharges. Detailed ideal MHD calculations using the NOVA code show both modification of plasma pressure and pressure gradient at play an important role in modifying the RSAE activity. Analysis of the ECH injection near the case where no frequency sweeping RSAEs are observed shows the typical RSAE is no longer an eigenmode of the system. What remains is an eigenmode with poloidal harmonic content reminiscent of the standard RSAE, but absent of the typical frequency sweeping behavior. The remaining eigenmode is also often strongly coupled to gap TAEs. Analysis with the non-perturbative gyro fluid code TAEFL confirms this change in RSAE activity and also shows a large drop in the resultant mode growth rates.

Recent results from the DIII-D tokamak have provided significant contributions to the understanding of many of the elements of tokamak physics and the application of this understanding to the design of next generation devices including ITER and CIT. The limitations of magnetohydrodynamic stability on the values of plasma beta (the ratio of kinetic pressure to the containing pressure of the magnetic field) that can be attained has been experimentally demonstrated and found to be described by existing theory. Values of beta (10.7%) well in excess of those required for proposed devices (ITER and CIT) have been demonstrated. Regimes of confinement (H-mode) have been established that scale favorably to proposed next generation devices, and experiments demonstrating the dependence of the energy confinement on plasma size have been completed. Understanding of confinement is rapidly developing especially in the areas of bulk transport and the role of turbulence in the plasma edge. Key experimental results in areas of plasma transport and edge plasma phenomena are in agreement with theories based on short wavelength turbulence. Control of the divertor heat loads and impurity influx has been demonstrated, and new progress has been made in the understanding of plasma edge phenomena. Experiments with ion Bernstein wave heating have not found regimes in which these waves can produce effective central ion heating. Electron cyclotron current drive experiments have demonstrated 70 kA of driven current in 400 kA discharges.

Joseph Biederman,1,2 Thomas J Spencer,1,2 Carter Petty,1 Laran L Hyder,1 Katherine B O’Connor,1 Craig BH Surman,1,2 Stephen V Faraone31Clinical and Research Program in Pediatric Psychopharmacology and Adult ADHD, Massachusetts General Hospital, Pediatric Psychopharmacology Unit, Yawkey Center for Outpatient Care, Boston, MA, 2Department of Psychiatry, Harvard Medical School, Cambridge, MA, 3Departments of Psychiatry and of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, NYBackground: While symptoms of deficient emotional self-regulation (DESR) have been long associated with attention-deficit/hyperactivity disorder (ADHD), there has been limited investigation of this aspect of the clinical picture of the disorder. The main aim of this study was to examine the predictive utility of DESR in moderating the course of ADHD children into adolescence.Methods: Subjects comprised 177 children with and 204 children without ADHD followed for an average of 4 years (aged 6–18 years at baseline, 54% male). Subjects were assessed with structured diagnostic interviews and measures of psychosocial functioning. DESR was defined by the presence (n = 79) or absence (n = 98) of Child Behavior Checklist (CBCL)-DESR profile (score ≥ 180 < 210 total of Attention, Aggression, and Anxious/Depressed subscales) at the baseline assessment.Results: Of subjects with DESR at baseline, 57% had DESR at follow-up. Persistent ADHD was significantly associated with DESR at follow-up (χ2(1) = 15.37, P < 0.001). At follow-up, ADHD + DESR subjects had significantly more comorbidities (z = 2.55, P = 0.01), a higher prevalence of oppositional defiant disorder (z = 3.01, P = 0.003), and more impaired CBCL social problems t-score (t(227) = 2.41, P = 0.02) versus ADHD subjects.Conclusion: This work suggests that a positive CBCL-DESR profile predicts subsequent psychopathology and functional impairments in children with ADHD suggesting that it has the potential to help identify children with ADHD at high risk for compromised outcomes.Keywords: attention-deficit/hyperactivity disorder, emotion, regulation, longitudinal, youth

This work provides a first experimental measurement of broadened ECH deposition on the DIIID tokamak. As seen in theory[1] and simulation[2], refraction by edge density fluctuations shifts the path of RF waves, altering ECH and ECCD deposition. This paper reports on an initial experimental confirmation of broadened ECH deposition on DIII-D tokamak. Te measurements from a 48 channel 2nd Harmonic ECE Radiometer digitized at 500 kHz are used with a set of broadened trial ECH deposition functions to calculate time-dependent, modulation-induced heat fluxes. The fitting of convective and diffusive transport to these fluxes allows different ECH deposition profiles to be compared. The best-fit ECH deposition produces reasonable transport coefficients which compare favorably with simulation. This method is applied to a set of L- and H- mode DIII-D discharges. Accounting for diffusive, convective, and coupled transport, the ECH deposition profile is found to be 2 to 3 times wider than predicted by TORAY-GA ray tracing.

The design, manufacture and concepts behind a modular diode-pump source for lasers based on microchannel cooling technology are presented. The proposed pump packages were developed for direct high power pumping of slab lasers. They were tested for performance and efficiency on a neodymium-doped ytrrium aluminum garnet slab laser using a 20% subset of the 80 pump diode packages. It yielded 70 W of average power at 100 microsecond pulsewidths.