Laser heated emissive probe (LHEP) for plasma potential measurement in the ADITYA-U tokamak
This article reports the first direct measurement of plasma potential, ϕ p l in the Last Closed Flux Surface (LCFS) of Ohmically heated Hydrogen plasma of ADITYA-U tokamak using Laser heated emissive probe (LHEP). Experiments have been conducted using the especially developed reciprocating diagnostic system with probe-holder assembly containing two identical planar disk-probes, one is heated with an IR laser (carbon-dioxide laser) and serves as an emissive probe, and the other is used as a cold Langmuir probe to facilitate statistical comparison of the measured parameters. The engineering design has been optimized with careful considerations of technical challenges, space constraints for the laser placement near the tokamak port and the alignment of the laser beam onto the probe-tip. The system is portable, compact, and can measure plasma potential at different radial locations in the Scrape Off-Layer (SOL)/edge region and LCFS of the Aditya-U tokamak on a shot-to-shot basis. Design, installation and evolution of the LHEP diagnostic system on the Aditya-U tokamak is presented in this paper. This work represents significant progress in plasma diagnostics by demonstrating the reliable operation of LHEP and the direct measurement of plasma potential in a tokamak environment.
Authors
- Santosh Dubey (ORCID: https://orcid.org/0000-0003-3169-1599)
- Sharvil Patel (ORCID: https://orcid.org/0000-0002-3112-7114)
- Dinesh Rathod (ORCID: https://orcid.org/0000-0002-0037-6468)
- Ankit Kumar (ORCID: https://orcid.org/0000-0003-4953-1614)
- Komal Yadav (ORCID: https://orcid.org/0009-0004-0588-5407)
- Minsha Shah (ORCID: https://orcid.org/0000-0002-4600-1354)
- Santosh P. Pandya (ORCID: https://orcid.org/0000-0002-4672-7083)
- Kalpesh Galodiya
- P. K. Srivastava (ORCID: https://orcid.org/0000-0002-6652-5948)
- K. Premjit Singh (ORCID: https://orcid.org/0000-0002-3549-9820)
- Laxmikanta Pradhan
- Tanmay Macwan (ORCID: https://orcid.org/0000-0002-9767-0830)
- Suman Aich (ORCID: https://orcid.org/0000-0003-3561-9180)
- Abha Kanik (ORCID: https://orcid.org/0009-0001-1906-7438)
- Pramila Gautam (ORCID: https://orcid.org/0009-0003-2187-6925)
- Rakesh L. Tanna (ORCID: https://orcid.org/0000-0003-4613-7072)
- Prabal Kumar Chattopadhyay (ORCID: https://orcid.org/0009-0008-6886-2789)
- Ramesh Kumar Buddu
- Harshita Raj (ORCID: https://orcid.org/0000-0001-6778-1292)
- Subhojit Bose (ORCID: https://orcid.org/0000-0003-3763-2071)
- M.B. Chowdhuri (ORCID: https://orcid.org/0000-0001-8313-1089)
- Amulya Kumar Sanyasi (ORCID: https://orcid.org/0000-0002-5454-9053)
- N. Ramaiya (ORCID: https://orcid.org/0000-0002-4668-4087)
- Injamul Hoque (ORCID: https://orcid.org/0009-0002-9667-7747)
- Soumitra Banerjee (ORCID: https://orcid.org/0000-0002-7223-1436)
- Bharat Hegde (ORCID: https://orcid.org/0009-0001-9674-8552)
- Arun Sarma
- Bhoomi Khodiyar (ORCID: https://orcid.org/0009-0006-9205-7611)
- Rohit Kumar (ORCID: https://orcid.org/0000-0001-9776-0468)
- Ankit Patel
- Suraj Gupta
- Sudhir Kumar Sharma
- Vipul Tanna
- Bharat Verma
- Kumarpal Jadeja
- Kaushal Patel
- Mayank Niman
- K.P. Singh
- Shwetang Pandya
- Payal Pandit
Publication Details
- Journal
- Fusion Engineering and Design
- Published
- 2026-10-06
- DOI
- https://doi.org/10.1016/j.fusengdes.2026.116080
- Primary Topic
- Magnetic confinement fusion research
- Type
- article
- Field-Weighted Citation Impact
- 0.00