Heavy quark production in ep collisions at HERA. [None] Page: 1 of 5
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
This report was prepared as an account of work sponsored by an agency of the United States
Government. Neither the United States Government nor any agency thereof, nor any of their
employees, makes any warranty, express or implied, or assumes any legal liability or responsi-
bility for the accuracy, completeness, or usefulness of any information, apparatus, product, or
process disclosed, or represents that its use would not infringe privately owned rights. Refer-
ence herein to any specific commercial product, process, or service by trade name, trademark,
manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom-
mendation, or favoring by the United States Government or any agency thereof. The views
and opinions of authors expressed herein do not necessarily state or reflect those of the
United States Government or any agency thereof.
HEAVY QUARK PRODUCTION IN ep COLLISIONS AT HERA
Argonne National Laboratory
Argonne, IL 60439
There are substantial production rates of heavy quarks from ep collisions
at HERA. The center of mass energy of about 300 GeV is well above any b-quark
threshold effects, and for b5 production, the cross section is estimated to be
3.3 nb per event, leading to rates approaching 106 b mesons per year. The
rates for cc production are about two orders of magnitude greater. Two major
detectors are under construction and a program of heavy quark physics will
start in 1990.
Almost all of our information on the properties of heavy quarks has come
from e+e- experiments since, although the data rates are low, 40% of the cross
section is represented by the cc and bE final states. In hadronic collisions,
the signal-to-noise is at least one thousand times worse and experimental
difficulties have, so far, not allowed the much higher rate of heavy quark
production to be fully exploited. Photoproduction is somewhere between e+e-
and hadronic collisions, both in rate and in signal to noise. The success of
the tagged photon beam program at Fermilab, following the introduction of a
silicon vertex detector, shows that charm physics can be done at a hadron
machine, using yp collisions, that is fully competitive with the e+e
experiments. Although the rate is very low in in neutrino bubble chamber
experiments, a few fully-reconstructed charm events have been seen.
In the next generation of facilities, these experiments will be continued
using ep collisions. A 30-GeV electron beam colliding with an 820-GeV proton
beam gives a center of mass energy equivalent to a 52-TeV photon beam on a
The submitted manuscript has been authored
by a contractor of the U S. Government
under contract No. W-31-109ENG-38.
Accordingly, the U. S. Government retains a
nonexclusive, royalty-free license to publish
or reproduce the published form of this
contribution, or allow others to do so, for
U. S. Government purposes.
DISTRIBUTON GF T1, 'Zl 2 C U LUTED
~k~- grjiih2~.5- /6)
Here’s what’s next.
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Derrick, M. Heavy quark production in ep collisions at HERA. [None], article, December 22, 1987; Illinois. (https://digital.library.unt.edu/ark:/67531/metadc1056034/m1/1/: accessed April 24, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.