Engineering topics

Kumar, J.

Publications and source records attributed to Kumar, J..

4 records

DOE OSTI2022

B-flavor tagging at Belle II

We report on new flavor tagging algorithms developed to determine the quark-flavor content of bottom (B) mesons at Belle II. The algorithms provide essential inputs for measurements of quark-flavor mixing and charge-parity violation. We validate and evaluate the performance of the algorithms using hadronic B decays with flavor-specific final states reconstructed in a data set corresponding to an integrated luminosity of 62.8fb -1 , collected at the Υ(4S) resonance with the Belle II detector at the SuperKEKB collider. We measure the total effective tagging efficiency to be ε eff = (30.0 ± 1.2(stat) ± 0.4(syst))% for a category-based algorithm and ε eff = (28.8 ± 1.2(stat) ± 0.4(syst))% for a deep learning-based algorithm.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

Snowmass2021 Cosmic Frontier: The landscape of low-threshold dark matter direct detection in the next decade

The search for particle-like dark matter with meV-to-GeV masses has developed rapidly in the past few years. We summarize the science case for these searches, the recent progress, and the exciting upcoming opportunities. Funding for Research and Development and a portfolio of small dark matter projects will allow the community to capitalize on the substantial recent advances in theory and experiment and probe vast regions of unexplored dark-matter parameter space in the coming decade.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

Status of the PIP-II Cryoplant

The Proton Improvement Plan-II (PIP-II) is an essential upgrade to the Fermilab accelerator complex featuring a new 800-MeV Superconducting Radio-Frequency (SRF) linear accelerator (Linac). The Linac contains 23 SRF cryomodules with the SRF cavities operating at 2 K, a high temperature thermal shield at 40 K and low temperature intercepts at 4.5 K. The PIP-II cryoplant will provide the necessary cooling for the cryomodules and the cryogenic distribution system interconnecting cryoplant and cryomodules. This paper describes the evolution of the PIP-II cryoplant conceptual design and specifications, including the expected heat loads, required cooling features and the integrated design. The cryoplant capacity margin analysis and fast cool-down mode will also be discussed.

43 PARTICLE ACCELERATORS↗

DOE OSTI2021

Jaynesian Analysis of Environmental Chemistry: Systems Model Component Integration via the Arctic Aquatic Carbon Cycle

Focal Areas: All three are touched upon from the OBER call. We will consider formal logical inference and entropic information analysis for sparse but intensive chemical measurements, as optimal drivers for managing process complexity. As a centerpiece for the discussion we take soil-to-sea organic structural evolution within the Arctic hydro-geochemosphere, assessing detrital negentropy then algorithmic greed to generate ranked, reduced mechanisms for system integration.

54 ENVIRONMENTAL SCIENCES↗