The d+d -> 4He+pi0 reaction is forbidden by charge symmetry,
and is therefore sensitive to the difference in the masses
of the up and down quarks.
Experiment CE-82
at
IUCF
was designed to measure its cross section near threshold.
In order to extract information about the quark mass difference,
one needs to calculate the effects of the isospin-conserving
dynamics, and estimate the size of other isospin-breaking effects.
A collaboration of theorists has been formed to tackle these issues.
This web page contains postings relevant to this effort.
If you want something posted, please send it to
Bira van Kolck.
Relevant papers:
Proposal for the first workshop,
"Computing sigma (d d --> 4He pi0) and Charge Symmetry Breaking",
held at the
INT, Seattle, August 23-25, 2001:
ps,
by Jerry Miller and Bira van Kolck
Report on our first workshop:
ps,
by Jerry Miller and Bira van Kolck
Homework problem:
ps,
by Jerry Miller and Antonio Fonseca
Schedule of the second workshop,
held at the Hyatt Regency Hotel, Albuquerque, April 19, 2002:
ps,
by Jerry Miller and Bira van Kolck
List of tasks assigned at our second workshop:
ps,
by Jerry Miller, Andy Bacher and Bira van Kolck
Results of Fonseca's new code at 6.1 MeV:
ps,
by Antonio Fonseca (May 28, 2002)
Phase space for the dd --> 4He pi0 reaction:
ps,
by Jerry Miller (July 03, 2002)
Partial decomposition of the isospin-breaking pion production operator
at threshold:
ps,
by Andreas Nogga (July 23, 2002)
Schedule of the third workshop,
held at
IUCF,
Bloomington, August 24-25, 2002:
ps,
by Chuck Horowitz, edited by Bira van Kolck (August 23, 2002)
Informal report on the third workshop:
ps,
by Chuck Horowitz, edited by Bira van Kolck (August 26, 2002)
Second homework problem:
ps,
by Chuck Horowitz (August 26, 2002)
Gardestig's talk at the third workshop:
ps,
by Anders Gardestig (August 26, 2002)
List of pion production operators:
ps,
by Chuck Horowitz and Jerry Miller (August 29, 2002)
Huge effect of initial-state interactions:
ps,
by Jerry Miller (September 13, 2002)
Leading and next-to-leading CSB operators:
ps,
by Chris Hanhart (September 26, 2002)
List of operators:
ps,
by Chris Hanhart (January 16, 2003)
Allena's results:
ps,
by Allena Opper (April 14, 2003)
Informal report on the fourth meeting:
ps,
by Jerry Miller, edited by Bira van Kolck (April 21, 2003)
How to antisymmetrize scattering states:
pdf,
by Andreas Nogga (April 22, 2003)
Heavy meson exchange operators:
ps,
by Chuck Horowitz (April 22, 2003)
Observation of the Charge Symmetry Breaking d + d -> 4He + pi0 Reaction Near Threshold:
nucl-ex/0305032,
by Ed Stephenson et al (June 02, 2003)
Revised Weinberg operator:
ps,
by Jerry Miller (June 16, 2003)
Charge symmetry breaking in n p -> d pi0:
nucl-ex/0306027,
by Allena Opper et al (June 20, 2003)
Horowitz's talk at the 2003 Gordon Conference on Nuclear Physics:
pdf
and
accompanying note,
by Chuck Horowitz (July 26, 2003)
First paper:
abstract, ps, pdf, etc.,
by Anders Gardestig et al. (February 04, 2004)
Trento proposal:
ps,
by Chuck Horowitz et al. (May 27, 2004)
Minutes of 10/27 Meeting:
ps,
by Jerry Miller (November 08, 2004)
CHARGE SYMMETRY VIOLATION IN P N ---> D PI0 AS A
TEST OF CHIRAL EFFECTIVE FIELD THEORY.
By U. van Kolck (Caltech, Kellogg Lab & Washington U., Seattle),
J.A. Niskanen (Helsinki U.), G.A. Miller (Washington U., Seattle).
KRL-MAP-267, NT-UW-00-15, Jun 2000. 10pp.
Published in Phys.Lett.B493:65-72,2000
e-Print Archive: nucl-th/0006042
EFFECTIVE FIELD THEORY CONTRIBUTION TO CHARGE SYMMETRY BREAKING N N SCATTERING.
By J.A. Niskanen (Helsinki U.). Aug 2001. 8pp.
Published in Phys.Rev.C65:037001,2002
e-Print Archive: nucl-th/0108015
PHENOMENOLOGICAL ASPECTS OF ISOSPIN VIOLATION IN THE NUCLEAR FORCE.
By U. van Kolck (Washington U., Seattle), J.L. Friar, T. Goldman (Los Alamos). Jan 1996. 10pp.
Published in Phys.Lett.B371:169-174,1996
e-Print Archive: nucl-th/9601009
COMPLETE NEXT-TO-LEADING ORDER CALCULATION FOR PION PRODUCTION IN NUCLEON-NUCLEON COLLISIONS AT THRESHOLD.
By C. Hanhart (Julich, Forschungszentrum), N. Kaiser (Munich, Tech. U.). Aug 2002. 9pp.
Published in Phys.Rev.C66:054005,2002
e-Print Archive: nucl-th/0208050
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