107 research outputs found
Innovative Configuration for a Far Infrared Space Interferometer
In the last ten years many proposals and studies have been advanced for a far-IR kilometer baseline interferometer. This paper shows the results of FISICA (Far Infrared Space Interferometer Critical Assessment), an FP7 program of the European Community. In particular, we focus on an innovative strategy to cover the plane of observation with a minimal propellant consumption. Results of some numerical simulations, carried out for a three-booms configuration, are provided
Testing the Equivalence Principle in an Einstein Elevator: Detector Dynamics and Gravity Perturbations
We discuss specific, recent advances in the analysis of an experiment to test the Equivalence Principle (EP) in free fall. A differential accelerometer detector with two proof masses of different materials free falls inside an evacuated capsule previously released from a stratospheric balloon. The detector spins slowly about its horizontal axis during the fall. An EP violation signal (if present) will manifest itself at the rotational frequency of the detector. The detector operates in a quiet environment as it slowly moves with respect to the co-moving capsule. There are, however, gravitational and dynamical noise contributions that need to be evaluated in order to define key requirements for this experiment. Specifically, higher-order mass moments of the capsule contribute errors to the differential acceleration output with components at the spin frequency which need to be minimized. The dynamics of the free falling detector (in its present design) has been simulated in order to estimate the tolerable errors at release which, in turn, define the release mechanism requirements. Moreover, the study of the higher-order mass moments for a worst-case position of the detector package relative to the cryostat has led to the definition of requirements on the shape and size of the proof masses
Rapporto sull’attività 29 Giugno – 6 Luglio 2013
In questo lavoro viene descritta la campagna geofisica e idro-oceanografica ‘GARGANO2013’
effettuata grazie ad una collaborazione tra INGV e Marina Militare Italiana nell’ambito di un accordo di
collaborazione denominato CONAGEM (Coordinamento Nazionale per la Geofisica Marina). Tale accordo, siglato nel 2005 fra i principali enti pubblici di ricerca che operano in mare, prevede infatti la possibilità di attuare congiuntamente campagne di ricerca marine condividendone dati e risultati.
La campagna è stata organizzata con la finalità di raccogliere quanti più possibili elementi utili a
caratterizzare l’area marina del Gargano sotto un profilo ambientale predisponendone un quadro di
riferimento per successive attività di monitoraggio delle fenomenologie presenti nell’area di indagine. In quest’ottica, l’obiettivo prefissato era la mappatura di eventuali affioramenti di acque dolci in mare.
Contestualmente, è stata eseguita la sperimentazione di prototipi strumentali per future applicazioni a bordo nave: in particolare, sono state eseguite misure di tipo accelerometrico al fine di caratterizzare le sollecitazioni dinamiche cui sono sottoposti gli strumenti a bordonave ottenendo così utili informazioni per lo sviluppo di nuove tecnologie quali piattaforme inerziali per uso scientifico e strumentazione per prospezioni gravimetriche da utilizzare su nave
Multiparametric seafloor exploration: the Marsili Basin and Volcanic Seamount case (Tyrrhenian Sea, Italy)
Exploration of ocean seafloor is of paramount importance for a better understanding of the
geodynamic evolution of our Planet. The pilot experiment of ORION-GEOSTAR 3 EC project was the first
long-term continuous geophysical and oceanographic experiment of an important seafloor area of Southern
Tyrrhenian Sea, the Marsili abyssal plain. The latter hosts the Marsili Seamount which is Europe’s one of the
largest underwater volcano of Plio-Pleistocenic age. In spite of its dimensions, it is rather unknown about the
present characteristics and activity. For this reason, we deployed a deep-sea observatory network, composed
by two bottom observatories, on the seafloor at the base of the seamount at 3320 m b.s.l., in the period
December 2003-May 2005. Some of the instruments on board the observatory were: broad-band
seismometers, hydrophones, gravity meter, two magnetometers (scalar and vectorial), 3D single-point
current meter, ADCP, CTD, automatic pH analyser and off-line water sampler for laboratory analyses. The
first successful scientific objective was to obtain long-term continuous recordings under a unique time
reference. The data analysis shows that they are generally of good quality and really continuous (only a few
gaps). As a first step we performed a classification of seismic waveforms, a first inversion of magnetic
variational data, and a first analysis of gravity meter, chemical and oceanographic data. Analysis of
individual time series has shown interesting results, i.e. depth of the magnetic Moho under the Marsili,
attenuation of recorded seismic body waves and clues of hydrothermal circulation. We show examples of the
preliminary data analysis together with first results and comparisons among data coming from different
sensors.PublishedCambridge, UK, February 24-26, 20091.8. Osservazioni di geofisica ambientale3.8. Geofisica per l'ambienteope
Towards a permanent deep sea observatory,: the GEOSTAR European Experiment.
GEOSTAR is the prototype of the first European long-term, multidisciplinary deep sea observatory for continuous monitoring of geophysical, geochemical and oceanographic parameters. Geostar is the example of a strong synergy between science and tecnology addressed to the development of new technological solutions for the observatory realisation and management. The GEOSTAR system is described outlining the enhancements introduced during five years of project activity. An example of data retrieved from the observatory being the deep sea mission running is also given.Published111-1202.5. Laboratorio per lo sviluppo di sistemi di rilevamento sottomarinireserve
Multiparametric seafloor exploration: the Marsili Basin and Volcanic Seamount case (Tyrrhenian Sea, Italy)
Exploration of ocean seafloor is of paramount importance for a better understanding of the
geodynamic evolution of our Planet. The pilot experiment of ORION-GEOSTAR 3 EC project was the first
long-term continuous geophysical and oceanographic experiment of an important seafloor area of Southern
Tyrrhenian Sea, the Marsili abyssal plain. The latter hosts the Marsili Seamount which is Europe’s one of the
largest underwater volcano of Plio-Pleistocenic age. In spite of its dimensions, it is rather unknown about the
present characteristics and activity. For this reason, we deployed a deep-sea observatory network, composed
by two bottom observatories, on the seafloor at the base of the seamount at 3320 m b.s.l., in the period
December 2003-May 2005. Some of the instruments on board the observatory were: broad-band
seismometers, hydrophones, gravity meter, two magnetometers (scalar and vectorial), 3D single-point
current meter, ADCP, CTD, automatic pH analyser and off-line water sampler for laboratory analyses. The
first successful scientific objective was to obtain long-term continuous recordings under a unique time
reference. The data analysis shows that they are generally of good quality and really continuous (only a few
gaps). As a first step we performed a classification of seismic waveforms, a first inversion of magnetic
variational data, and a first analysis of gravity meter, chemical and oceanographic data. Analysis of
individual time series has shown interesting results, i.e. depth of the magnetic Moho under the Marsili,
attenuation of recorded seismic body waves and clues of hydrothermal circulation. We show examples of the
preliminary data analysis together with first results and comparisons among data coming from different
sensors
Precision measurement of and determination of the contribution to the muon anomaly with the KLOE detector
We have measured the ratio
, with the KLOE detector at DANE for a total integrated
luminosity of 240 pb. From this ratio we obtain the cross section
. From the cross section we determine the
pion form factor and the two-pion contribution to the muon anomaly
for GeV, = . This result confirms the
current discrepancy between the Standard Model calculation and the experimental
measurement of the muon anomaly.Comment: 18 pages, 8 figures, minor text corrections, one table added, version
to appear on Physics Letters
Measurement of {\eta} meson production in {\gamma}{\gamma} interactions and {\Gamma}({\eta}-->{\gamma}{\gamma}) with the KLOE detector
We present a measurement of {\eta} meson production in photon-photon
interactions produced by electron-positron beams colliding with \sqrt{s}=1 GeV.
The measurement is done with the KLOE detector at the \phi-factory DA{\Phi}NE
with an integrated luminosity of 0.24 fb^{-1}. The e^+e^- --> e^+e^-{\eta}
cross section is measured without detecting the outgoing electron and positron,
selecting the decays {\eta}-->{\pi}^+{\pi}^-{\pi}^0 and
{\eta}-->{\pi}^0{\pi}^0{\pi}^0. The most relevant background is due to e^+e^-
--> {\eta}{\gamma} when the monochromatic photon escapes detection. The cross
section for this process is measured as {\sigma}(e^+e^- -->{\eta}{\gamma}) =
(856 \pm 8_{stat} \pm 16_{syst}) pb. The combined result for the e^+e^-
-->e^+e^-{\eta} cross section is {\sigma}(e^+e^- -->e^+e^-{\eta}) = (32.72 \pm
1.27_{stat} \pm 0.70_{syst}) pb. From this we derive the partial width
{\Gamma}({\eta}-->{\gamma}{\gamma}) = (520 \pm 20_{stat} \pm 13_{syst}) eV.
This is in agreement with the world average and is the most precise measurement
to date.Comment: Version accepted by JHE
A new limit on the CP violating decay KS -> 3pi0 with the KLOE experiment
We have carried out a new direct search for the CP violating decay KS -> 3pi0
with 1.7 fb^-1 of e+e- collisions collected by the KLOE detector at the
phi-factory DAFNE. We have searched for this decay in a sample of about 5.9 x
10^8 KS KL events tagging the KS by means of the KL interaction in the
calorimeter and requiring six prompt photons. With respect to our previous
search, the analysis has been improved by increasing of a factor four the
tagged sample and by a more effective background rejection of fake KS tags and
spurious clusters. We find no candidates in data and simulated background
samples, while we expect 0.12 standard model events. Normalizing to the number
of KS -> 2pi0 events in the same sample, we set the upper limit on BR(KS ->
3pi0 < 2.6 x 10^-8 at 90% C.L., five times lower than the previous limit. We
also set the upper limit on the eta_000 parameter, |eta_000 | < 0.0088 at 90%
C.L., improving by a factor two the latest direct measurement.Comment: Accepted for publication in Physics Letters B (15 pages, 13 figures
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