Jose A. Boedo is a Spanish plasma

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

and a researcher at

University of California, San Diego The University of California, San Diego (UC San Diego in communications material, formerly and colloquially UCSD) is a public university, public Land-grant university, land-grant research university in San Diego, California, United States. Es ...

. He was elected as a fellow of the

American Physical Society The American Physical Society (APS) is a not-for-profit membership organization of professionals in physics and related disciplines, comprising nearly fifty divisions, sections, and other units. Its mission is the advancement and diffusion of ...

in 2016 for "his ground-breaking contributions to the studies of plasma drifts and intermittent plasma transport in the peripheral region of

tokamak A tokamak (; ) is a device which uses a powerful magnetic field generated by external magnets to confine plasma (physics), plasma in the shape of an axially symmetrical torus. The tokamak is one of several types of magnetic confinement fusi ...

s". Boedo is known for pioneering work in the characteristics, particle and energy transport, and dynamics of the edge and scrape-off layer and

divertor In magnetic confinement fusion, a divertor is a magnetic field configuration which diverts the heat and particles escaped from the magnetically confined plasma to dedicated plasma-facing components, thus spatially separating the region plasma ...

s of tokamaks, the leading candidate device for fusion energy. These works have focused on intermittent transport and the role of cross-phase in transport modulation by velocity shear.

Early life and career

Boedo received his Ph.D. from the

University of Texas at Austin The University of Texas at Austin (UT Austin, UT, or Texas) is a public university, public research university in Austin, Texas, United States. Founded in 1883, it is the flagship institution of the University of Texas System. With 53,082 stud ...

. In 1990, he joined

UCLA The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California, United States. Its academic roots were established in 1881 as a normal school then known as the southern branch of the C ...

as a researcher in the mechanical and aerospace engineering department. In 1995, he moved to the

and has been there ever since.

Scientific contributions

Early in his career, Boedo investigated the role of externally imposed electric fields on tokamak plasmas and the corresponding velocity shear in the suppression of turbulence. Until then, the observed effect of velocity shear on reducing turbulence was consistent with theoretical expectations, but causality had not been demonstrated. It was the existence under externally applied

electric field An electric field (sometimes called E-field) is a field (physics), physical field that surrounds electrically charged particles such as electrons. In classical electromagnetism, the electric field of a single charge (or group of charges) descri ...

s and concomitant velocity shear, that closed the causality loop. Boedo characterized the reduction of transport and compared the scaling of the suppression with known theories. Additionally, he was the first to show that velocity shear also reduced temperature fluctuations, and therefore, the conductive

heat flux In physics and engineering, heat flux or thermal flux, sometimes also referred to as heat flux density, heat-flow density or heat-flow rate intensity, is a flow of energy per unit area per unit time (physics), time. Its SI units are watts per sq ...

. Boedo investigated the effect that injected impurities on tokamak plasmas in producing enhanced energy confinement, known as the I-mode. He was the first to show that the enhancement in performance was due to reduction in transport and turbulence due to ITG mode suppression. Boedo has also done pioneering work on the role of flows and drifts in the edge, SOL (scrape-off layer), and divertor of tokamaks. He was the first to experimentally demonstrate that once the divertor plasma is detached, there is a considerable residual heat flux that is convected by the plasma to the walls via large,

Mach The Mach number (M or Ma), often only Mach, (; ) is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a Boundary (thermodynamic), boundary to the local speed of sound. It is named after the Austrian physi ...

=1 large scale flows. Boedo has shown that the effect of ExB drifts in the SOL and divertor plasmas is significant, and therefore edge simulation codes such as UEDGE and SOLPS should include drifts to properly model the boundary plasma. Boedo worked closely with modelers in experiment-modeling efforts to demonstrate the relevance of the drifts. In the late 1990s, it was found in the

Alcator C-Mod Alcator C-Mod was a tokamak (a type of magnetically confined fusion device) that operated between 1991 and 2016 at the Massachusetts Institute of Technology (MIT) Plasma Science and Fusion Center (PSFC). Notable for its high toroidal magnetic ...

tokamak that plasma-wall contact was much larger than expected, revealing missing transport mechanism/physics in the edge/SOL in tokamaks. Boedo and his colleagues then quantified, characterized and experimentally demonstrated that plasma was carried form the plasma edge towards the SOL and the chamber walls by intermittent, convective transport that was subsequently identified as resulting from the

interchange instability The interchange instability, also known as the Kruskal–Schwarzschild instability or flute instability, is a type of plasma instability seen in magnetic fusion energy that is driven by the gradients in the magnetic pressure in areas where the c ...

. As theoretical understanding of the subject improves, Boedo has continued to research the topic, particularly on the scaling of intermittent transport with plasma parameters. Boedo also developed tools to study and characterize Edge Localized Modes (ELMs) at high time resolution. The heat released by ELMs towards the walls of fusion devices is a major concern for future devices. Boedo quantified the ELM-mediated particle and heat transport that among other results, highlighted the two-dimensional nature of the phenomena as filaments and discovered that such filaments have a complex structure. Boedo's recent work has been focused on the physics of intrinsic rotation in tokamaks and the realization that asymmetric, thermal ion loss is a significant mechanism in determining a source of rotation at the edge of the plasma that is then transported into the core. Boedo identified and characterized the edge rotation from a theoretical point of view and compared it to existing models. Boedo has also made contributions towards the diagnostic development for plasmas. He has developed high heat flux, fixed and reciprocating, scanning probes, such as that built for the NSTX tokamak, a rotating

Langmuir probe A Langmuir probe is a device used to determine the electron temperature, electron density, and electric potential of a plasma. It works by inserting one or more electrodes into a plasma, with a constant or time-varying electric potential between ...

, and also a diagnostic to measure electron temperature with better than 400 kHz bandwidth. Between 1999 and 2014, Boedo gave 5 invited talks at international plasma physics conferences.

Early life and career

Scientific contributions

References

Further reading