WWW.DIS.XLIBX.INFO
FREE ELECTRONIC LIBRARY - Thesis, dissertations, books
 
<< HOME
CONTACTS



Pages:     | 1 ||

«AB-Note-2005-030 BDI On the Potential Use of Zero Degree Calorimeters for LHC Luminosity Monitoring H. Schmickler – CERN 1211 Geneva 23 - CH S. ...»

-- [ Page 2 ] --

Due to the coincidence technique the background rates can be measured and corrected to a high precision, provided the machine is stable enough to have long integration times.

The feature of theZDCs of being linear of 5 orders of magnitude offers the possibility to convey absolute luminosity calibrations from TOTEM like measurements at very low luminosities to operational luminosities up to 1033.

It should be kept in mind that during Pb-Pb running periods of LHC the ZDC’s record a calculable cross section, as described in ref.1. This provides a potentially very useful calibration of the absolute luminosity determination by other means.

2.6 Role of Timing Measurements 2.6.1 Beam Profile The intrinsic timing resolution of the ZDC is of order 150 psec. Since we digitize the time over threshold for each bunch crossing we can use this to calculate the location along the beam axis of a collision and in real time produce a distribution of the luminous region.

–  –  –

This real-time plot is often used at RHIC during r.f. commissioning, for example.

2.6.2 Commissioning Beam Crossing Angle The longitudinal profile of the luminous region has several other potential roles in commissioning. For example, at some point during commissioning a finite crossing angle (150µrad) between beams will be introduced to prevent parasitic collisions between bunches outside the IR. It would be nice to have a commissioning tool that measures the actual angle.

Several times during RHIC operation a finite crossing angle was (unintentionally) introduced. This angle was seen very easily as soon as either beam underwent a displacement. This happened during vernier scans or simple luminosity tweaking.

Since under a transverse displacement of x cms the Zinteraction moves by

–  –  –

References [1] A. J. Baltz, C. Chasman and S. White, Nucl. Instr. And Meth. A417, 1 (1998).

[2] C. Adler et al., Nucl. Instr. And Meth. A470, 488 (2001).

[3] M. Chiu et al. Phys. Rev. Lett. 89 (2002) 012302, nucl-ex/0109018.

[4] A discussion of the role of ZDC in diffractive measurements at RHIC and LHC can be found in S.White, ”Inelastic Diffraction at Heavy Ion Colliders” - http://www.arxiv.org/pdf/nuclex/0501004 and to be published in Nucl. Phys. B..



Pages:     | 1 ||


Similar works:

«THE CITY OF NEW YORK DEPARTMENT OF CITYWIDE R EQ UIR ED FO RM S ADMINISTRATIVE SERVICES APPLICATION UNIT 1 CENTRE STREET, 14TH FLOOR APPLICATION FORM NEW YORK, NY 10007 NOTICE MICHAEL R. BLOOMBERG OF Mayor EXAMINATION EDNA WELLS HANDY Commissioner PROMOTION TO MOTOR VEHICLE SUPERVISOR (For Agencies Under the Jurisdiction of DCAS Only) Exam No. 1517 Second Amended Notice: April 6, 2011 WHEN TO APPLY: From: April 6, 2011 APPLICATION FEE: $61.00 To: April 26, 2011 If you pay online by credit card,...»

«DEVELOPING DATABASE ON SECURITIES HOLDERS INFORMATION: THE CASE OF JAPAN Prepared for the WPFS Workshop on Securitization held on 27-28 May 2010 Yoshiko Sato Research and Statistics Department Bank of Japan ABSTRACT Identifying the exact holder or the holding sector of securities is always one of the most challenging tasks for statistical compilers. Recently, some central banks and statistical authorities have started projects to build up securities databases in which securities holders’...»

«2009 Fundación IASC: Material de formación sobre la NIIF para las PYMES Módulo 17: Propiedades, Planta y Equipo Fundación IASC: Material de formación sobre la NIIF para las PYMES que incluye el texto completo de la Sección 17 Propiedades, Planta y Equipo de la Norma Internacional de Información Financiera para Pequeñas y Medianas Entidades (NIIF para las PYMES) publicado por el Consejo de Normas Internacionales de Contabilidad el 9 de julio de 2009 con explicaciones amplias, preguntas...»

«Honan insurancegroup Residential Landlords Property Insurance Product Disclosure Statement (PDS) This PDS is dated 01 July 2015 Issued by Chubb Insurance Company of Australia Limited ABN 69 003 710 647 AFSL No. 239778 Promoted by Honan Insurance Group Pty Ltd ABN 67 005 372 396 AFSL No. 246749 www.honan.com.au Table Of Contents Part 1 About Our Residential Landlords Property Insurance 1. Introduction 2 2. Words with a special meaning 2 3. Who is the insurer 2 4. About Honan Insurance Group 3 5....»





 
<<  HOME   |    CONTACTS
2016 www.dis.xlibx.info - Thesis, dissertations, books

Materials of this site are available for review, all rights belong to their respective owners.
If you do not agree with the fact that your material is placed on this site, please, email us, we will within 1-2 business days delete him.