A Proposal for a Ton Scale Bubble Chamber for Dark Matter Detection

PDF Version Also Available for Download.

Description

The nature of non-baryonic dark matter is one of the most intriguing questions for particle physics at the start of the 21st century. There is ample evidence for its existence, but almost nothing is known of its properties. WIMPs are a very appealing candidate particle and several experimental campaigns are underway around the world to search for these particles via the nuclear recoils that they should induce. The COUPP series of bubble chambers has played a significant role in the WIMP search. Through a sequence of detectors of increasing size, a number of R&D issues have arisen and been solved, ... continued below

Physical Description

36 pages

Creation Information

Collar, Juan; Dahl, C.Eric; Fustin, Drew; Robinson, Alan; U., /Chicago; Behnke, Ed et al. October 7, 2010.

Context

This report 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 report can be viewed below.

Who

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

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 report. Follow the links below to find similar items on the Digital Library.

Description

The nature of non-baryonic dark matter is one of the most intriguing questions for particle physics at the start of the 21st century. There is ample evidence for its existence, but almost nothing is known of its properties. WIMPs are a very appealing candidate particle and several experimental campaigns are underway around the world to search for these particles via the nuclear recoils that they should induce. The COUPP series of bubble chambers has played a significant role in the WIMP search. Through a sequence of detectors of increasing size, a number of R&D issues have arisen and been solved, and the technology has now been advanced to the point where the construction of large chambers requires a modest research effort, some development, but mostly just engineering. It is within this context that we propose to build the next COUPP detector - COUPP-500, a ton scale device to be built over the next three years at Fermilab and then deployed deep underground at SNOLAB. The primary advantages of the COUPP approach over other technologies are: (1) The ability to reject electron and gamma backgrounds by arranging the chamber thermodynamics such that these particles do not even trigger the detector. (2) The ability to suppress neutron backgrounds by having the radioactively impure detection elements far from the active volume and by using the self-shielding of a large device and the high granularity to identify multiple bubbles. (3) The ability to build large chambers cheaply and with a choice of target fluids. (4) The ability to increase the size of the chambers without changing the size or complexity of the data acquisition. (5) Sensitivity to spin-dependent and spin-independent WIMP couplings. These key advantages should enable the goal of one background event in a ton-year of exposure to be achieved. The conceptual design of COUPP-500 is scaled from the preceding devices. In many cases all that is needed is a simple scaling up of components previously used. Calibration and R&D are still needed on some aspects of the system. We know we have the ability to distinguish alpha-induced events from nuclear recoils, but we do not yet know whether the combination of material purity and rejection are good enough to run for a year with no alpha background. We also need to have more detailed measurements of the detector threshold and a better understanding of its high gamma rejection. In addition, there are important checks to make on the longevity of the detector components in the hydraulic fluid and on the chemistry of the active fluid. The 2009 PASAG report explicitly supported the construction of the COUPP-500 device in all funding scenarios. The NSF has shown similar enthusiasm. It awarded one of its DUSEL S4 grants to assist in the engineering needed to build COUPP-500. The currently estimated cost of COUPP-500 is $8M, about half the $15M-$20M price tag expected by the PASAG report for a next generation dark matter search experiment. The COUPP-500 device will have a spin independent WIMP-nucleus cross-section sensitivity of 6 x 10{sup -47} cm{sup 2} after a background-free year of running. This device should then provide the benchmark against which all other WIMP searches are measured.

Physical Description

36 pages

Language

Item Type

Identifier

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

  • Report No.: FERMILAB-PROPOSAL-1009
  • Grant Number: AC02-07CH11359
  • DOI: 10.2172/992651 | External Link
  • Office of Scientific & Technical Information Report Number: 992651
  • Archival Resource Key: ark:/67531/metadc1014351

Collections

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

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this report?

When

Dates and time periods associated with this report.

Creation Date

  • October 7, 2010

Added to The UNT Digital Library

  • Oct. 14, 2017, 8:36 a.m.

Description Last Updated

  • Oct. 24, 2017, 3:17 p.m.

Usage Statistics

When was this report last used?

Congratulations! It looks like you are the first person to view this item online.

Interact With This Report

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

Citations, Rights, Re-Use

Collar, Juan; Dahl, C.Eric; Fustin, Drew; Robinson, Alan; U., /Chicago; Behnke, Ed et al. A Proposal for a Ton Scale Bubble Chamber for Dark Matter Detection, report, October 7, 2010; Batavia, Illinois. (digital.library.unt.edu/ark:/67531/metadc1014351/: accessed December 11, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.