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Title: A Proposal to Search for Charmed Particle Production Near Threshold

Abstract

We propose to search for charmed particle production thresholds by looking for anomalies in the ratio of K{sup -}/{pi}{sup -} production at P{sub T} {approx} 1 GeV/c as the incident energy is varied. Any anomalous behavior will be further investigated using a two arm effective mass spectrometer.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
910472
Report Number(s):
FERMILAB-PROPOSAL-0363
TRN: US200724%%181
DOE Contract Number:
AC02-07CH11359
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; EFFECTIVE MASS; PARTICLE PRODUCTION; PRODUCTION; SPECTROMETERS; KAONS

Citation Formats

Gross, D., Nitz, D., Olsen, S., /Rochester U., Abe, K., Bomberowitz, R., Cohen, K., Margulies, M., Sannes, F., /Rutgers U., Piscataway, Colleraine, A., /Florida State U., Siotis, I., and /Imperial Coll., London. A Proposal to Search for Charmed Particle Production Near Threshold. United States: N. p., 1974. Web. doi:10.2172/910472.
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Gross, D., Nitz, D., Olsen, S., /Rochester U., Abe, K., Bomberowitz, R., Cohen, K., Margulies, M., Sannes, F., /Rutgers U., Piscataway, Colleraine, A., /Florida State U., Siotis, I., & /Imperial Coll., London. A Proposal to Search for Charmed Particle Production Near Threshold. United States. doi:10.2172/910472.
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Gross, D., Nitz, D., Olsen, S., /Rochester U., Abe, K., Bomberowitz, R., Cohen, K., Margulies, M., Sannes, F., /Rutgers U., Piscataway, Colleraine, A., /Florida State U., Siotis, I., and /Imperial Coll., London. Fri . "A Proposal to Search for Charmed Particle Production Near Threshold". United States. doi:10.2172/910472. https://www.osti.gov/servlets/purl/910472.
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@article{osti_910472,
title = {A Proposal to Search for Charmed Particle Production Near Threshold},
author = {Gross, D. and Nitz, D. and Olsen, S. and /Rochester U. and Abe, K. and Bomberowitz, R. and Cohen, K. and Margulies, M. and Sannes, F. and /Rutgers U., Piscataway and Colleraine, A. and /Florida State U. and Siotis, I. and /Imperial Coll., London},
abstractNote = {We propose to search for charmed particle production thresholds by looking for anomalies in the ratio of K{sup -}/{pi}{sup -} production at P{sub T} {approx} 1 GeV/c as the incident energy is varied. Any anomalous behavior will be further investigated using a two arm effective mass spectrometer.},
doi = {10.2172/910472},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Nov 01 00:00:00 EST 1974},
month = {Fri Nov 01 00:00:00 EST 1974}
}
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DOI:  10.2172/910472
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  • Experimental results on a search for charmed particle production in proton-proton collisions at the center of mass energy (..sqrt..s) of 53 GeV are presented. A search was made for evidence of electron-strange particle coincidences, a signature of charmed particle production. The inclusive e/..pi.. ratio was measured with a magnetic spectrometer located at 32/sup 0/ from Beam 1 of Intersection 16 of the CERN Intersecting Storage Rings (ISR). The e/..pi.. ratio from direct (unknown) sources was found to rise from 1.06 x 10/sup -4/ at p/sub perpendicular to/ = 1.5 GeV/c to 5.53 x 10/sup -4/ at p/sub perpendicular to/ =more » 0.25 GeV/c. One possible source for this signal is the semi-leptonic decay of charmed particles (e.g. D ..-->.. K/sup 0/ev). If so, then electron-strange particle (e.g., ..lambda../sup 0/,K/sup 0/) coincidences are expected. The charged decay products of ..lambda../sup 0/ and K/sup 0/ were detected in a multiparticle spectrometer surrounding Beam 1 downstream of the intersection. To determine if there is an electron-strange particle correlation, the number of ..lambda../sup 0/'s (K/sup 0/'s) in coincidence with an electron in the 32/sup 0/ spectrometer was compared with the number of ..lambda..'s (K/sup 0/'s) in coincidence with a hadron in the same kinematic range. No evidence for an enhanced production of strange particles with electrons relative to hadrons was found. However, given the acceptance of the apparatus, the absence of a signal is consistent with current models of charmed particle production and decay.« less

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