Operations aspects of the Fermilab Central Helium Liquefier Facility

The Fermilab Central Helium Liquefier (CHL) facility consists of helium and nitrogen reliquefier plants operated 24 hours-a-day to supply LHe at 4.6{degrees}K and LN{sub 2} for the Fermilab Tevatron superconducting proton-antiproton collider ring and to recover warm return gases. Operating aspects of CHL, including different equipment and systems reliability, availability, maintenance experience, safety concerns, and economics aspects are discussed

Operations aspects of the Fermilab Central Helium Liquefier facility

The Fermilab Central Helium Liquefier (CHL) facility consists of helium and nitrogen reliquefier plants operated 24 hours-a-day to supply LHe at 4.6 K and LN{sub 2} for the Fermilab Tevatron superconducting proton-antiproton collider ring and to recover warm return gases. Operating aspects of CHL, including different equipment and systems reliability, availability, maintenance experience, safety concerns, and economics aspects are discussed

A Proposal for a Three Detector Short-Baseline Neutrino Oscillation Program in the Fermilab Booster Neutrino Beam

A Short-Baseline Neutrino (SBN) physics program of three LAr-TPC detectors located along the Booster Neutrino Beam (BNB) at Fermilab is presented. This new SBN Program will deliver a rich and compelling physics opportunity, including the ability to resolve a class of experimental anomalies in neutrino physics and to perform the most sensitive search to date for sterile neutrinos at the eV mass-scale through both appearance and disappearance oscillation channels. Using data sets of 6.6e20 protons on target (P.O.T.) in the LAr1-ND and ICARUS T600 detectors plus 13.2e20 P.O.T. in the MicroBooNE detector, we estimate that a search for muon neutrino to electron neutrino appearance can be performed with ~5 sigma sensitivity for the LSND allowed (99% C.L.) parameter region. In this proposal for the SBN Program, we describe the physics analysis, the conceptual design of the LAr1-ND detector, the design and refurbishment of the T600 detector, the necessary infrastructure required to execute the program, and a possible reconfiguration of the BNB target and horn system to improve its performance for oscillation searches.Comment: 209 pages, 129 figure

Design and construction of the MicroBooNE detector

This paper describes the design and construction of the MicroBooNE liquid argon time projection chamber and associated systems. MicroBooNE is the first phase of the Short Baseline Neutrino program, located at Fermilab, and will utilize the capabilities of liquid argon detectors to examine a rich assortment of physics topics. In this document details of design specifications, assembly procedures, and acceptance tests are reported

General P-T fit construction for He, N sub 2 , Ar, H sub 2 and Ne VPT used at Fermilab

Polynomial fits are constructed for Fermilab Tevatron vapor pressure thermometers (VPT) for use with ACNET database. Fit coefficients and P-T graphs are included. Fits cover the VPT saturation region and the gas region. The thermodynamic analysis of VPT bulb is used to define transition points for each cryogenic VPT with given geometry and charge'' conditions. The methodology is described to repeat fit construction calculations for any geometry and charge'' conditions if required

Mathematical modeling of a Fermilab helium liquefier coldbox

Fermilab Central Helium Liquefier (CHL) facility is operated 24 hours-a-day to supply 4.6{degrees}K for the Fermilab Tevatron superconducting proton-antiproton collider Ring and to recover warm return gases. The centerpieces of the CHL are two independent cold boxes rated at 4000 and 5400 liters/hour with LN{sub 2} precool. These coldboxes are Claude cycle and have identical heat exchangers trains, but different turbo-expanders. The Tevatron cryogenics demand for higher helium supply from CHL was the driving force to investigate an installation of an expansion engine in place of the Joule-Thompson valve. A mathematical model was developed to describe the thermo- and gas-dynamic processes for the equipment included in the helium coldbox. The model is based on a finite element approach, opposite to a global variables approach, thus providing for higher accuracy and conversion stability. Though the coefficients used in thermo- and gas-dynamic equations are unique for a given coldbox, the general approach, the equations, the methods of computations, and most of the subroutines written in FORTRAN can be readily applied to different coldboxes. The simulation results are compared against actual operating data to demonstrate applicability of the model

Cryogenic system for the Tevatron

Supporting the world`s highest energy proton/antiproton collider in high energy physics research, the Fermilab Tevatron cryogenic system consists of a hybrid system of a Central Helium Liquefier feeding twenty-four 1 kW satellite refrigerators through a 6.5 km transfer line and supplying the liquid helium for the superconducting magnets of the accelerator and liquid nitrogen for the thermal shielding. Tevatron upgrades have been completed by 1996 and resulted in more than doubling the CHL liquefaction capacity, potential decrease of magnet operating temperatures from 4.9 K to 3.9 K and proven increase of Tevatron energy from 900 GeV to 990 GeV without losing operational stability