91 citations · 474 across the 32 of their papers we have counts for
18 papers · 1 filter
High- Treatment of CEBAF 1.5 GHz SRF Cavities
Pashupati Dhakal
The Continuous Electron Beam Accelerator Facility (CEBAF) was the first large-scale accelerator to employ superconducting radiofrequency (SRF) cavities for continuous-wave operatio…
Role of microstructure on flux expulsion of superconducting radio frequency cavities
B. D. Khanal, S. Balachandran, S. Chetri +8
The trapped residual magnetic flux during the cool-down due to the incomplete Meissner state is a significant source of radio frequency losses in superconducting radio frequency (S…
Impact of medium temperature heat treatment on flux trapping sensitivity in SRF cavities
Pashupati Dhakal, Bashu Dev Khanal, Eric Lechner +1
The effect of mid-T heat treatment on flux trapping sensitivity was measured on several 1.3 GHz single cell cavities subjected to vacuum annealing at temperature of 150 - 400 $^\ci…
Evaluation of flux expulsion and flux trapping sensitivity of srf cavities fabricated from cold work Nb sheet with successive heat treatment
B. D. Khanal, P. Dhakal
The main source of RF losses leading to lower quality factor of superconducting radio-frequency cavities is due to the residual magnetic flux trapped during cool-down. The loss due…
Development of a prototype superconducting radio-frequency cavity for conduction-cooled accelerators
G. Ciovati, J. Anderson, S. Balachandran +18
The higher efficiency of superconducting radio-frequency (SRF) cavities compared to normal-conducting ones enables the development of high-energy continuous-wave linear accelerator…
RF Accelerator Technology R&D: Report of AF7-rf Topical Group to Snowmass 2021
Sergey Belomestnykh, Emilio A. Nanni, Hans Weise +18
Accelerator radio frequency (RF) technology has been and remains critical for modern high energy physics (HEP) experiments based on particle accelerators. Tremendous progress in ad…
Medium-Grain Niobium SRF Cavity Production Technology for Science Frontiers and Accelerator Applications
G. Myneni, Hani E. Elsayed-Ali, Md Obidul Islam +15
We propose cost-effective production of medium grain (MG) niobium (Nb) discs directly sliced from forged and annealed billet. This production method provides clean surface conditio…
Nitrogen Doping and Infusion in SRF Cavities: A Review
Pashupati Dhakal
Advances in SRF technology over the last 40 years allowed achieving accelerating gradients ~ 50 MV/m corresponding to peak surface magnetic field close to the theoretical limit of…
Effect of Low Temperature Baking in Nitrogen on the Performance of a Niobium Superconducting Radio Frequency Cavity
Pashupati Dhakal, Santosh Chetri, Shreyas Balachandran +2
We report the rf performance of a single-cell superconducting radiofrequency cavity after low temperature baking in a nitrogen environment. A significant increase in quality factor…
Role of Thermal Resistance on the Performance of Superconducting Radio Frequency Cavities
Pashupati Dhakal, Gianluigi Ciovati, Ganapati Rao Myneni
Thermal stability is an important parameter for the operation of the superconducting radio frequency (SRF) cavities used in particle accelerators. The rf power dissipated on the in…
Enhancement in Quality Factor of SRF Niobium Cavities by Material Diffusion
Pashupati Dhakal, Gianluigi Ciovati, Peter Kneisel +1
An increase in the quality factor of superconducting radiofrequency cavities is achieved by minimizing the surface resistance during processing steps. The surface resistance is the…
Reply to "Comment on the 'Decrease of the surface resistance in superconducting niobium resonator cavities by the microwave field'"
G. Ciovati, P. Dhakal, A. Gurevich
In a recent comment [arXiv:1405.2978v1 (2014)] Romanenko and Grassellino made unsubstantiated statements about our work [Appl. Phys. Lett. 104, 092601 (2014)] and ascribed to us wr…
Analysis of post wet chemistry heat treatment effects on Nb SRF surface resistance
Pashupati Dhakal, Gianluigi Ciovati, Peter Kneisel +1
Most of the current research in superconducting radio frequency (SRF) cavities is focused on ways to reduce the construction and operating cost of SRF based accelerators as well as…
The Rise of Ingot Niobium as a Material for Superconducting Radiofrequency Accelerating Cavities
P. Kneisel, G. Ciovati, P. Dhakal +4
As a result of a collaboration between Jefferson Lab and niobium manufacturer CBMM, ingot niobium was explored as a possible material for superconducting radiofrequency (SRF) cavit…
Comment on "Proximity breakdown of hydrides in superconducting niobium cavities" [arXiv:1212.3384]
G. Ciovati, P. Dhakal, G. R. Myneni
Comment on Proximity breakdown of hydrides in superconducting niobium cavities [arXiv:1212.3384].
A Path to Higher Q0 with Large Grain Niobium Cavities
Pashupati Dhakal, Gianluigi Ciovati, Ganapati Rao Myneni
The improvement of the quality factor Q0 of superconducting radio-frequency (SRF) cavities at medium accelerating gradients (20-25 MV/m) is important in order to reduce the cryogen…
Superconducting DC and RF Properties of Ingot Niobium
Pashupati Dhakal, Gianluigi Ciovati, Peter Kneisel +1
The thermal conductivity, DC magnetization and penetration depth of large-grain niobium hollow cylindrical rods fabricated from ingots, manufactured by CBMM subjected to chemical a…
Flux pinning characteristics in cylindrical ingot niobium used in superconducting radio frequency cavity fabrication
Asavari S. Dhavale, Pashupati Dhakal, Anatolii A. Polyanskii +1
We present the results of from DC magnetization and penetration depth measurements of cylindrical bulk large-grain (LG) and fine-grain (FG) niobium samples used for the fabrication…