The frequency of the protonium annihilation channel
pp → K
SK
L
has been measured at three different target densities: liquid hydrogen (
LH), gaseous hydrogen at NTP conditions and gaseous hydrogen ...at low pressure (5 mbar). The obtained results are:
f(
pp → K
SK
L, LH) = (7.8 ± 0.7
stat
± 0.3
sys
) × 10
−4
,
f(
pp → K
SK
L, NTP) = (3.5 ± 0.5
stat
± 0.2
sys) × 10
−4
and
f(
pp → K
SK
L, 5
mbar) = (1.0 ± 0.3
stat
± 0.1
sys
) × 10
−4
. Since the
K
S
K
L
final stat and be originated only from the
3
S
1 initial state, these values give direct information on the scaling of the protonium spin-triplet S-wave annihilation probability with the density.
We describe the possibilities of signal processing allowed by the new fully numerical data analysis system developed for the 100
mK resonant gravitational wave antenna AURIGA. We summarize some new ...ideas, in different stages of practical implementation, which have relevant consequences for the simultaneous analysis of the data coming from detectors located at different sytes. Among these a self consistency test on signal amplitudes for two or more parallel detectors.
To assess reliability of information about nutritional facts stated on labels of foods marketed.
A total of 153 industrialized foods, usually consumed by children and adolescents and marketed in the ...city of São Paulo, Southeastern Brazil, between 2001 and 2005, were analyzed. Nutrient contents stated on labels were compared to the results obtained from official (physical-chemical) analytical methods, considering the 20% variability tolerated by the current legislation to approve or reject samples. Means, standard deviations, 95% confidence intervals for the nutrients analyzed, and the distribution of percentage frequency of samples rejected were calculated.
All salty products analyzed showed non-compliance of dietary fiber, sodium and saturated fat content. Sweet products showed variation between zero and 36% of rejection due to their dietary fiber content. More than half (52%) of cookies were rejected due to their saturated fat content. Nutrients associated with obesity and its health problems were those showing the highest proportions of non-compliance. Lack of reliability of label information in the samples analyzed violates the regulations of the Resolution of the Collegiate Board of Directors RDC 360/03 and the rights guaranteed by the Nutritional and Food Safety Law and Consumer Protection Code.
High indices of non-compliance of nutritional data were found on labels of foods aimed at children and adolescents, indicating the urgent need for surveillance practices and other nutritional labeling measures.
A VME based multiprocessor system for on-line data analysis is presented. The system is based on a master CPU board that distributes incoming event buffers to several slave CPUs running the same ...analysis program. A large shared memory is provided to hold final histograms. A Vaxstation, linked to the system via Ethernet, provides control and graphics management of the analyzed data. A numerical simulation of the system is described and results are compared with real performance obtained using a prototype of the system.
Resonant detectors for gravitational waves Baggio, L.; Bonaldi, M.; Cerdonio, M. ...
Advances in space research,
2000, 2000-1-00, 20000101, Letnik:
25, Številka:
6
Journal Article
Recenzirano
For the first time a number of cryogenic resonant bar detectors of gravitational waves — ALLEGRO, AURIGA, EXPLORER, NAUTILUS, NIOBE — are on the air, in a continuous search for impulsive events. We ...present their capabilities, the foreseen upgrades and their role in a future global network with interferometric detectors.
In this work, we use the coherent WaveBurst (cWB) pipeline enhanced with machine learning (ML) to search for binary black hole (BBH) mergers in the Advanced LIGO-Virgo strain data from the third ...observing run (O3). We detect, with equivalent or higher significance, all gravitational-wave (GW) events previously reported by the standard cWB search for BBH mergers in the third GW Transient Catalog (GWTC-3). The ML-enhanced cWB search identifies five additional GW candidate events from the catalog that were previously missed by the standard cWB search. Moreover, we identify three marginal candidate events not listed in GWTC-3. For simulated events distributed uniformly in a fiducial volume, we improve the detection efficiency with respect to the standard cWB search by approximately \(20\%\) for both stellar-mass and intermediate mass black hole binary mergers, detected with a false-alarm rate less than \(1\,\mathrm{yr}^{-1}\). We show the robustness of the ML-enhanced search for detection of generic BBH signals by reporting increased sensitivity to the spin-precessing and eccentric BBH events as compared to the standard cWB search. Furthermore, we compare the improvement of the ML-enhanced cWB search for different detector networks.
Gravitational wave astronomy is established with direct observation of gravitational wave from merging binary black holes and binary neutron stars during the first and second observing run of LIGO ...and Virgo detectors. The gravitational-wave transient searches mainly categories into two families: modeled and modeled-independent searches. The modeled searches are based on matched filtering techniques and model-independent searches are based on the extraction of excess power from time-frequency representations. We have proposed a hybrid method, called wavegraph that mixes the two approaches. It uses astrophysical information at the extraction stage of model-independent search using a mathematical graph. In this work, we assess the performance of wavegraph clustering in real LIGO and Virgo noises (the sixth science run and the first observing run) and using the coherent WaveBurst transient search as a backbone. Further, we propose a new signal consistency test for this algorithm. This test uses the amplitude profile information to distinguish between the gravitational wave transients from the noisy glitches. This test is able to remove a large fraction of loud glitches, which thus results in additional overall sensitivity in the context of searches for binary black-hole mergers in the low-mass range.
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