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Padamsee, H.

Publications and source records attributed to Padamsee, H..

8 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Superconducting radio frequency linear collider HELEN

This article discusses a proposed Higgs-Energy LEptoN (HELEN) $e^+e^-$ linear collider based on advanced traveling wave superconducting radio frequency technology. Here, the proposed collider offers cost and AC power savings, smaller footprint (relative to the ILC), and could be built at Fermilab. After the initial physics run at 250 GeV, the collider could be upgraded either to higher luminosity or to higher, up to 500 GeV, energies.

43 PARTICLE ACCELERATORS↗
DOE OSTI2023

An 8 GeV linac as the Booster replacement in the Fermilab Power Upgrade

Increasing the Main Injector beam power above ~ 1.2 MW requires replacement of the 8 GeV Booster by a higher intensity alternative. In this paper, we consider an 8 GeV linac Booster replacement that produces 8 GeV H$^{-}$ beam for injection into the Recycler Ring or Main Injector. This upgrade will maximize the beam available for neutrino production for the long baseline DUNE experiment to greater than 2.5 MW and enable a next generation frontier experiments. The 8 GeV linac takes ~ 1 GeV beam from the PIP-II Linac and accelerates it to ~ 2 GeV in a650 MHz superconducting RF linac, followed by a ~ 2 to 8 GeV pulsed linac using 1300 MHz cryomodules. The linac components incorporate recent improvements in superconducting RF technology. The linac configuration and beam dynamics requirements are presented. Injection options are discussed, including use of an8 GeV Accumulator Ring. Foil-based injection is the present standard but R&D toward implementing laser-assisted injection could enable a significant improvement. Research needed to implement the Booster replacement is described.

43 PARTICLE ACCELERATORS↗
DOE OSTI2023

HELEN: Traveling Wave SRF Linear Collider Higgs Factory

Traveling wave SRF accelerating structures offer several advantages over the traditional standing wave structures: substantially lower $H_pk/E_acc$ and lower $E_pk/E_acc$, ratios of peak magnetic field and peak electric field to the accelerating gradient, respectively, together with substantially higher $R/Q$. In this paper we discuss how a linear collider Higgs Factory HELEN can be built using TW-based SRF linacs. We cover a plan to address technological challenges and describe ways to upgrade the collider luminosity and energy.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

HELEN: A Linear Collider Based On Advanced SRF Technology

This paper discusses recently proposed Higgs Energy LEptoN (HELEN) $e+e-$ linear collider based on advances in superconducting radio frequency technology. The collider offers cost and AC power savings, smaller footprint (relative to the ILC), and could be built at Fermilab with an interaction region within the site boundaries. After the initial physics run at 250 GeV, the collider could be upgraded either to higher luminosity or to higher (up to 500 GeV) energies.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

Higgs-Energy LEptoN (HELEN) Collider based on advanced superconducting radio frequency technology

This Snowmass 2021 contributed paper discusses a Higgs-Energy LEptoN (HELEN) e⁺e⁻ linear collider based on advances superconducting radio frequency technology. The proposed collider offers cost and AC power savings, smaller footprint (relative to the ILC), and could be built at Fermilab with an Interaction Region within the site boundaries. After the initial physics run at 250 GeV, the collider could be upgraded either to higher luminosity or to higher (up to 500 GeV) energies. If the ILC could not be realized in Japan in a timely fashion, the HELEN collider would be a viable option to build a Higgs factory in the U.S.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

Optimization of a traveling wave superconducting radiofrequency cavity for upgrading the International Linear Collider

The standing wave TESLA niobium-based superconducting radio frequency structure is limited to an accelerating gradient of about 50 MV/m by the critical rf magnetic field. To break through this barrier, we explore the option of niobium-based traveling wave (TW) structures. Optimization of TW structures was done considering experimentally known limiting electric and magnetic fields. It is shown that a TW structure can have an accelerating gradient above 70 MeV/m that is about 1.5 times higher than contemporary standing wave structures with the same critical magnetic field. The other benefit of TW structures shown is R/Q about 2 times higher than the TESLA structure that reduces the dynamic heat load by a factor of 2. A method is proposed how to make TW structures multipactor-free. Some design proposals are offered to facilitate fabrication. Further increase of the real-estate gradient (equivalent to 80 MV/m active gradient) is also possible by increasing the length of the accelerating structure because of higher group velocity and cell-to-cell coupling. Realization of this work opens paths to International Linear Collider energy upgrades beyond 1 to 3 TeV in competition with CLIC. The paper will discuss corresponding opportunities and challenges.

43 PARTICLE ACCELERATORS↗