BEGIN:VCALENDAR VERSION:2.0 PRODID:-//linuxsoftware.nz//NONSGML Joyous v1.4//EN BEGIN:VEVENT SUMMARY:Dynamics of the inboard and outboard density profile at ASDEX Upgr ade DTSTART:20240216T090000Z DTEND:20240216T110000Z DTSTAMP:20260929T165956Z UID:c428eed0-bff8-48e7-9831-d8f58be69a31 SEQUENCE:2 CREATED:20240209T104322Z DESCRIPTION:We present our studies of the scrape-off layer (SOL) at ASDEX Upgrade\, focusing on the behavior of the inboard SOL in different magneti c configurations and the dynamics of the high-density region near the inbo ard plasma edge. Understanding SOL behavior is essential to manage heat ex haust and achieve a detached operation in current and future reactors. We investigate the existence of hollow density profiles at the inboard midpla ne SOL by combining several diagnostics and using a novel interpretation o f reflectometry data that relies on analyzing the spectral signatures of t he beat signal. We show that the poloidal density asymmetry can influence line-integrated measurements\, such as interferometry\, and should be incl uded in an integrated data analysis. We investigate the role of the magnet ic configuration in shaping the inboard SOL profile\, particularly as the plasma approaches a double-null configuration typical of many reactor desi gns. Our investigations reveal a narrowing of the inboard SOL profile\, dr iven by the magnetic disconnection from the outboard SOL\, underscoring th e importance of magnetic topology and parallel heat conduction in determin ing the inboard SOL properties. We see a steep density gradient at the sec ondary separatrix in both the midplane and divertor regions\, which we att ribute to the presence of the inboard high-density region\, observable usi ng reflectometry and Thomson scattering diagnostics. Near double-null\, a drastic reduction in conducted heat to the inboard SOL leads to decreased electron and neutral density in the inboard divertor. Lastly\, we observe that the high-density region is significantly suppressed in unfavorable fi eld configurations. We use these scenarios to measure the edge density dec ay length at the inboard and outboard midplane. We estimate a consistently larger outboard decay length than the inboard side\, with an average rati o of 1.7\, corroborating the expected ballooning nature of radial transpor t in tokamaks. LAST-MODIFIED:20240216T102408Z LOCATION:Anfiteatro PA-3 (Piso -1 do Pavilhão de Matemática) URL:http://df.vps.tecnico.ulisboa.pt/pt/eventos/dynamics-of-the-inboard-an d-outboard-density-profile-at-asdex-upgrade/ X-ALT-DESC;FMTTYPE=text/html:

We present our stud ies of the scrape-off layer (SOL) at ASDEX Upgrade\, focusing on the behav ior of the inboard SOL in different magnetic configurations and the dynami cs of the high-density region near the inboard plasma edge. Understanding SOL behavior is essential to manage heat exhaust and achieve a detached op eration in current and future reactors.

We investigate the exist ence of hollow density profiles at the inboard midplane SOL by combining s everal diagnostics and using a novel interpretation of reflectometry data that relies on analyzing the spectral signatures of the beat signal. We sh ow that the poloidal density asymmetry can influence line-integrated measu rements\, such as interferometry\, and should be included in an integrated data analysis.

We investigate the role of the magnetic configur ation in shaping the inboard SOL profile\, particularly as the plasma appr oaches a double-null configuration typical of many reactor designs. Our in vestigations reveal a narrowing of the inboard SOL profile\, driven by the magnetic disconnection from the outboard SOL\, underscoring the importanc e of magnetic topology and parallel heat conduction in determining the inb oard SOL properties.

We see a steep density gradient at the seco ndary separatrix in both the midplane and divertor regions\, which we attr ibute to the presence of the inboard high-density region\, observable usin g reflectometry and Thomson scattering diagnostics. Near double-null\, a d rastic reduction in conducted heat to the inboard SOL leads to decreased e lectron and neutral density in the inboard divertor.

Lastly\, we observe that the high-density region is significantly suppressed in unfav orable field configurations. We use these scenarios to measure the edge de nsity decay length at the inboard and outboard midplane. We estimate a con sistently larger outboard decay length than the inboard side\, with an ave rage ratio of 1.7\, corroborating the expected ballooning nature of radial transport in tokamaks.

END:VEVENT END:VCALENDAR