2,142 research outputs found
Transitions Induced by the Discreteness of Molecules in a Small Autocatalytic System
Autocatalytic reaction system with a small number of molecules is studied
numerically by stochastic particle simulations. A novel state due to
fluctuation and discreteness in molecular numbers is found, characterized as
extinction of molecule species alternately in the autocatalytic reaction loop.
Phase transition to this state with the change of the system size and flow is
studied, while a single-molecule switch of the molecule distributions is
reported. Relevance of the results to intracellular processes are briefly
discussed.Comment: 5 pages, 4 figure
Drawing on LGB Identity to Encourage Participation and Disclosure of Sexual Orientation in Surveys
This paper reports an experiment that tested how three survey cover designs—images of traditional families and individuals displaying themselves in typical gender ways; images of lesbian, gay, and bisexual (LGB) and heterosexual individuals and families; and no cover images—affected LGB people’s participation and disclosure of LGB identity and non-LGB people’s participation. Analyses showed the LGB-inclusive cover led to significantly more LGB respondents than the other designs, without significantly affecting the demographic, political, and religious makeup of the completed sample. We discuss what these findings mean for addressing two challenges: getting LGB people to respond to surveys and to disclose their LGB identity
The importance of tau leptons for supersymmetry searches at the Tevatron
Supersymmetry is perhaps most effectively probed at the Tevatron through
production and decay of weak gauginos. Most of the analyses of weak gaugino
observables require electrons or muons in the final state. However, it is
possible that the gauginos will decay primarily to tau leptons, thus
complicating the search for supersymmetry. The motivating reasons for high tau
multiplicity final states are discussed in three approaches to supersymmetry
model building: minimal supergravity, gauge mediated supersymmetry breaking,
and more minimal supersymmetry. The concept of ``e/mu/tau candidate'' is
introduced, and an observable with three e/mu/tau candidates is defined in
analog to the trilepton observable. The maximum mass reach for supersymmetry is
then estimated when gaugino decays to tau leptons have full branching fraction.Comment: 9 pages, latex, 2 figures. Presented at the D0 New Phenomena
Workshop, UC Davis, 26-28 March 199
New antlion records (Neuroptera: Myrmeleontidae) from Paraguay
New records of Myrmeleontidae from Paraguay are presented: Dimares elegans (Perty, 1833), Glenurus croesus Banks, 1922, Glenurus penningtoni (Navás, 1918a) and Vella fallax (Rambur, 1842). The total number of species now recorded from the country is fourteen among 11 genera. Specimens of Dimares elegans from east (Cerrado) and west (Chaco) of the Paraguay River are phenotypically distinct; those west of the Paraguay River are assigned to the form “lepida” Navás, 1912. More research is required to understand the taxonomic limits in this genus
New antlion records (Neuroptera: Myrmeleontidae) from Paraguay
New records of Myrmeleontidae from Paraguay are presented: Dimares elegans (Perty, 1833), Glenurus croesus Banks, 1922, Glenurus penningtoni (Navás, 1918a) and Vella fallax (Rambur, 1842). The total number of species now recorded from the country is fourteen among 11 genera. Specimens of Dimares elegans from east (Cerrado) and west (Chaco) of the Paraguay River are phenotypically distinct; those west of the Paraguay River are assigned to the form “lepida” Navás, 1912. More research is required to understand the taxonomic limits in this genus
New antlion records (Neuroptera: Myrmeleontidae) from Paraguay
New records of Myrmeleontidae from Paraguay are presented: Dimares elegans (Perty, 1833), Glenurus croesus Banks, 1922, Glenurus penningtoni (Navás, 1918a) and Vella fallax (Rambur, 1842). The total number of species now recorded from the country is fourteen among 11 genera. Specimens of Dimares elegans from east (Cerrado) and west (Chaco) of the Paraguay River are phenotypically distinct; those west of the Paraguay River are assigned to the form “lepida” Navás, 1912. More research is required to understand the taxonomic limits in this genus
Standard Model Higgs Physics at a 4 TeV Upgraded Tevatron
We compute an array of Standard Model Higgs boson (\hsm) signals and
backgrounds for a possible upgrade of the Tevatron to E_{\rm cm}=4\tev.
Taking \mt\geq 140\gev, and assuming a total accumulated luminosity of
L=30\fbi, we find that a Standard Model Higgs boson with \mhsm\lsim 110\gev
could almost certainly be detected using the \wpm\hsm\rta l\nu b\anti b mode.
A Higgs boson with mass between \sim 120\gev and \sim 140\gev or above
\sim 230-250\gev almost certainly would not be seen. A Higgs boson with
\mhsm\sim 150\gev or 200\lsim\mhsm\lsim 230-250\gev has a decent chance of
being detected in the ZZ\rta 4l mode. There would also be some possibility of
discovering the \hsm in the WW\rta l\nu jj mode for 150\lsim\mhsm\lsim
200\gev. Finally, hints of an event excess in the WW\rta ll \nu\nu mode due
to the \hsm might emerge for 140\lsim\mhsm\lsim 180\gev. Given the
difficult nature of the Higgs boson signals for \mhsm values beyond the reach
of LEP-200, and the discontinuous \mhsm range that could potentially be
probed, justification of an upgrade of the Tevatron to 4\tev on the basis of
its potential for Standard Model Higgs boson discovery would seem
inappropriate.Comment: 21 pages; requires phyzzx.tex and tables.tex; full postscript file
including embedded figures available via anonymous ftp at ucdhep.ucdavis.edu
as [anonymous.gunion]4tev.ps, preprint UCD-94-1
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