32 research outputs found
Design, status and perspective of the Mu2e crystal calorimeter
The Mu2e experiment at Fermilab will search for the charged lepton flavor
violating process of neutrino-less coherent conversion in the field
of an aluminum nucleus. Mu2e will reach a single event sensitivity of about
that corresponds to four orders of magnitude improvements
with respect to the current best limit. The detector system consists of a straw
tube tracker and a crystal calorimeter made of undoped CsI coupled with Silicon
Photomultipliers. The calorimeter was designed to be operable in a harsh
environment where about 10 krad/year will be delivered in the hottest region
and work in presence of 1 T magnetic field. The calorimeter role is to perform
/e separation to suppress cosmic muons mimiking the signal, while
providing a high level trigger and a seeding the track search in the tracker.
In this paper we present the calorimeter design and the latest RD results.Comment: 4 pages, conference proceeding for a presentation held at TIPP'2017.
To be published on Springer Proceedings in Physic
Limit on the production of a new vector boson in , U with the KLOE experiment
The recent interest in a light gauge boson in the framework of an extra U(1)
symmetry motivates searches in the mass range below 1 GeV.
We present a search for such a particle, the dark photon, in , U based on 28 million
events collected at DANE
by the KLOE experiment. The production by initial-state radiation
compensates for a loss of sensitivity of previous KLOE , searches due to the small branching ratios in
the resonance region. We found no evidence for a signal and set a
limit at 90\% CL on the mixing strength between the photon and the dark photon,
, in the U mass range between and ~MeV. Above 700 MeV
this new limit is more stringent than previous ones.Comment: 6 pages, 9 figures, 1 table, submitted to Phys. Lett.
Measurement of the transition form factor with the KLOE detector
A measurement of the vector to pseudoscalar conversion decay with the KLOE experiment is presented. A sample of signal
events was selected from a data set of 1.7 fb of collisions at
collected at the DANE collider. These
events were used to obtain the first measurement of the transition form factor
and a new measurement of the branching ratio of the
decay: . The result improves
significantly on previous measurements and is in agreement with theoretical
predictions.Comment: 13 pages, 4 figures; matches published versio
Precision measurement of the Dalitz plot distribution with the KLOE detector
Using fb of data collected with
the KLOE detector at DANE, the Dalitz plot distribution for the decay is studied with the world's largest sample of events. The Dalitz plot density is parametrized as a polynomial
expansion up to cubic terms in the normalized dimensionless variables and
. The experiment is sensitive to all charge conjugation conserving terms of
the expansion, including a term. The statistical uncertainty of all
parameters is improved by a factor two with respect to earlier measurements.Comment: 11 pages, 9 figures, supplement: an ascii tabl
Search for light vector boson production in interactions with the KLOE experiment
We have searched for a light vector boson , the possible carrier of a
"dark force", with the KLOE detector at the DANE \epm\ collider,
motivated by astrophysical evidence for the presence of dark matter in the
universe. Using \epm\ collisions collected with an integrated luminosity of
~pb, we look for a dimuon mass peak in the reaction \epm\to\gam, corresponding to the decay . We find no evidence
for a vector boson signal. We set a 90\% CL upper limit for the mixing
parameter squared between the photon and the boson of 1.610
to 8.610 for the mass region MeV.Comment: 12 pages, 7 figures, version accepted for publication in Physics
Letters
Quantum mechanics and CPT tests with neutral kaons at the KLOE experiment
Neutral kaons produced in the correlated pairs at the DAΦNE -factory offer unique possibilities to perform fundamental tests of CPT invariance, as well as of the basic principles of quantum mechanics. The analysis of the data collected by the KLOE experiment allows to improve results on several parameters describing CPT violation and decoherence, and to measure the regeneration cross section on the beam pipe materials
Search for dark Higgsstrahlung in e + e − → μ + μ − and missing energy events with the KLOE experiment KLOE-2 Collaboration
We searched for evidence of a Higgsstrahlung process in a secluded sector, leading to a final state with a dark photon U and a dark Higgs boson h , with the KLOE detector at DA NE. We investigated the case of h lighter than U , with U decaying into a muon pair and h producing a missing energy signature. We found no evidence of the process and set upper limits to its parameters in the range 2m μ < m U < 1000 MeV, m h < m U