The CO2 Gas Cherenkov Detectors for the Jefferson Lab Hall A Spectrometers

PDF Version Also Available for Download.

Description

Two threshold gas Cherenkov counters have been constructed for the electron and hadron High Resolution Spectrometers (HRS) of the Jefferson Lab Experimental Hall A. These counters are intended to separate electrons/positrons from other particles up to 4 GeV/c. The counters are operated at atmospheric pressure with CO2. Each counter is equipped with ten mirrors. Lightweight, thin, spherical mirrors (5.5 + 10{sup {minus}3} radiation lengths) have been employed resulting in a total thickness of 1.4 + 10{sup {minus}2} radiation lengths crossed by the particles. A prototype of the counter has been tested at CERN with a mixed beam of positrons, pions, ... continued below

Physical Description

725 Kilobytes pages

Creation Information

Iodice, M.; Cisbani, E.; Colilli, S.; Crateri, R.; Frullani, S.; Garibaldi, F. et al. June 1, 1998.

Context

This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this article can be viewed below.

Who

People and organizations associated with either the creation of this article or its content.

Sponsor

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this article. Follow the links below to find similar items on the Digital Library.

Description

Two threshold gas Cherenkov counters have been constructed for the electron and hadron High Resolution Spectrometers (HRS) of the Jefferson Lab Experimental Hall A. These counters are intended to separate electrons/positrons from other particles up to 4 GeV/c. The counters are operated at atmospheric pressure with CO2. Each counter is equipped with ten mirrors. Lightweight, thin, spherical mirrors (5.5 + 10{sup {minus}3} radiation lengths) have been employed resulting in a total thickness of 1.4 + 10{sup {minus}2} radiation lengths crossed by the particles. A prototype of the counter has been tested at CERN with a mixed beam of positrons, pions, and protons from 1 to 4 GeV/c. Its detection efficiency for positrons and the rejection ratios for pions and protons have been measured as a function of the pulse height response (or equivalently the number of photoelectrons). An improvement of 34% in the number of photoelectrons has been obtained by using a wavelength shifter coated on the photocathode glass window. With such an improvement in 1 m long radiator, an inefficiency for positrons less than 10{sup {minus}3} and rejection ratios pi/e at the level of few 10{sup {minus}3} and p/e smaller than 10{sup {minus}3} have been obtained for pulse heights above 2 photoelectrons. Contaminations of particles below the Cherenkov threshold is fully understood considering delta-rays production.

Physical Description

725 Kilobytes pages

Source

  • Journal Name: NIM (1998), p. 223-237; Journal Volume: A; Journal Issue: 411; Other Information: Submitted to NIM, Volume A: No.411

Language

Item Type

Identifier

Unique identifying numbers for this article in the Digital Library or other systems.

  • Report No.: JLAB-PHY-98-06
  • Report No.: DOE/ER/40150-1719
  • Grant Number: AC05-84ER40150
  • Office of Scientific & Technical Information Report Number: 765743
  • Archival Resource Key: ark:/67531/metadc724611

Collections

This article is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

What responsibilities do I have when using this article?

When

Dates and time periods associated with this article.

Creation Date

  • June 1, 1998

Added to The UNT Digital Library

  • Sept. 29, 2015, 5:31 a.m.

Description Last Updated

  • Feb. 5, 2016, 8:42 p.m.

Usage Statistics

When was this article last used?

Yesterday: 1
Past 30 days: 1
Total Uses: 7

Interact With This Article

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Iodice, M.; Cisbani, E.; Colilli, S.; Crateri, R.; Frullani, S.; Garibaldi, F. et al. The CO2 Gas Cherenkov Detectors for the Jefferson Lab Hall A Spectrometers, article, June 1, 1998; Newport News, Virginia. (digital.library.unt.edu/ark:/67531/metadc724611/: accessed September 22, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.