P. S. Cooper
A5070518531- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Atomic and Subatomic Physics Research
- Particle Detector Development and Performance
- Neuropeptides and Animal Physiology
- Nuclear Physics and Applications
- Radiation Detection and Scintillator Technologies
- Computational Physics and Python Applications
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Receptor Mechanisms and Signaling
- Pharmacological Receptor Mechanisms and Effects
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Cosmology and Gravitation Theories
- Astrophysics and Cosmic Phenomena
- Advanced SAR Imaging Techniques
- Chemical Synthesis and Analysis
- Muon and positron interactions and applications
- Black Holes and Theoretical Physics
- Drug Transport and Resistance Mechanisms
- Nuclear physics research studies
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2017-2024
Roma Tre University
2024
George Mason University
2017-2024
Centre National de la Recherche Scientifique
2024
Aix-Marseille Université
2024
UCLouvain
2022-2023
Fermi National Accelerator Laboratory
2009-2022
Joint Institute for Nuclear Research
2020
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2018
University of Pisa
2018
The Basic Local Alignment Search Tool (BLAST) website at the National Center for Biotechnology (NCBI) is an important resource searching and aligning sequences.A new BLAST report allows faster loading of alignments, adds navigation aids, easy downloading subject sequences reports has improved usability.Here, we describe these improvements to report, discuss design decisions, other search page database documentation outline plans future development.
An experiment has been performed to search for the muon- and electron-number nonconserving decay μ+→e+γ. The upper limit branching ratio is found be Γ(μ+→e+γ)/ Γ(μ+→e+ν¯ν)<1.2×10−11 with 90% confidence.Received 10 May 1999DOI:https://doi.org/10.1103/PhysRevLett.83.1521©1999 American Physical Society
We observe a signal for the doubly charmed baryon Xi(+)(cc) in charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) data from SELEX, charm hadroproduction experiment at Fermilab. an excess of 15.9 events over expected background 6.1+/-0.5 events, statistical significance 6.3sigma. The observed mass this state is 3519+/-1 MeV/c(2). Gaussian width 3 MeV/c(2), consistent with resolution; its lifetime less than 33 fs 90% confidence.
Experiment E949 at Brookhaven National Laboratory has observed three new events consistent with the decay K+→π+ν¯ν in pion momentum region 140<Pπ<199 MeV/c an exposure of 1.71×1012 stopped kaons estimated total background 0.93±0.17(stat)+0.32−0.24(syst) events. This brings number to seven. Combining this observation previous results, assuming spectrum predicted by standard model, results a branching ratio B(K+→π+ν¯ν)=(1.73+1.15−1.05)×10−10. An interpretation for alternative models...
New data are reported from the operation of a 4.0 kg CF$_{3}$I bubble chamber in 6800-foot-deep SNOLAB underground laboratory. The effectiveness ultrasound analysis discriminating alpha-decay background events single nuclear recoils has been confirmed, with lower bound $>$99.3% rejection events. Twenty recoil event candidates and three multiple were observed during total exposure 553 kg-days distributed over different nucleation thresholds. effective for recoil-like was 437.4 kg-days. A...
New results are reported from the operation of PICO-60 dark matter detector, a bubble chamber filled with 52 kg C_{3}F_{8} located in SNOLAB underground laboratory. As previous PICO chambers, exhibits excellent electron recoil and alpha decay rejection, observed multiple-scattering neutron rate indicates single-scatter background less than one event per month. A blind analysis an efficiency-corrected 1167-kg day exposure at 3.3-keV thermodynamic threshold reveals no single-scattering nuclear...
New data are reported from the operation of a 2 liter ${\mathrm{C}}_{3}{\mathrm{F}}_{8}$ bubble chamber in SNOLAB underground laboratory, with total exposure 211.5 kg days at four different energy thresholds below 10 keV. These show that provides excellent electron-recoil and alpha rejection capabilities very low thresholds. The exhibits an sensitivity $<3.5\ifmmode\times\else\texttimes\fi{}1{0}^{\ensuremath{-}10}$ factor $>98.2%$. also include first observation dependence acoustic signal on...
Final results are reported from operation of the PICO-60 C$_3$F$_8$ dark matter detector, a bubble chamber filled with 52 kg located in SNOLAB underground laboratory. The was operated at thermodynamic thresholds as low 1.2 keV without loss stability. A new blind 1404-kg-day exposure 2.45 threshold acquired approximately same expected total background rate previous 1167-kg-day 3.3 keV. This increased is enabled part by optical tracking analysis to better identify events near detector walls,...
Three events for the decay K+→π+ν¯ν have been observed in pion momentum region below K+→π+π0 peak, 140<Pπ<199 MeV/c, with an estimated background of 0.93±0.17(stat.)+0.32−0.24(syst.) events. Combining this observation previously reported results yields a branching ratio B(K+→π+ν¯ν)=(1.73+1.15−1.05)×10−10 consistent standard model prediction.Received 18 August 2008DOI:https://doi.org/10.1103/PhysRevLett.101.191802©2008 American Physical Society
Bubble Chambers provided the dominant particle detection technology in accelerator experiments for several decades, eventually falling into disuse with advent of other techniques. We report here on first period operation an ultra-clean, room-temperature bubble chamber containing 1.5 kg superheated CF$_{3}$I, a target maximally sensitive to spin-dependent and -independent Weakly Interacting Massive Particle (WIMP) couplings. An exposure excess 250 kg-days is obtained, live-time fraction...
Data from the operation of a bubble chamber filled with 3.5 kg CF3I in shallow underground site are reported. An analysis ultrasound signals accompanying nucleations confirms that alpha decays generate significantly louder acoustic emission than single nuclear recoils, leading to an efficient background discrimination. Three dark matter candidate events were observed during effective exposure 28.1 day, consistent neutron background. This observation provides strong direct detection...
New data are reported from the operation of PICO-60 dark matter detector, a bubble chamber filled with 36.8 kg CF$_3$I and located in SNOLAB underground laboratory. is largest to search for date. With an analyzed exposure 92.8 livedays, exhibits same excellent background rejection observed smaller chambers. Alpha decays exhibit frequency-dependent acoustic calorimetry, similar but not identical that recently C$_3$F$_8$ chamber. also observes large population unknown events, exhibiting...
Evidence of a heavy neutrino, $\nu_H$, in the $K^+\to\mu^+\nu_H$ decays was sought using E949 experimental data with an exposure $1.70\times 10^{12}$ stopped kaons. With major background from radiative $K^+\to\mu^+\nu_\mu\gamma$ decay understood and suppressed, upper limits (90% C.L.) on neutrino mixing matrix element between muon $|U_{\mu H}|^2$, were set at level $10^{-7}$ to $10^{-9}$ for mass region 175 300 MeV/$c^2$.
An additional event near the upper kinematic limit for K+-->pi(+)nunu; has been observed by experiment E949 at Brookhaven National Laboratory. Combining previously reported and new data, branching ratio is B(K+-->pi(+)nunu;)=(1.47(+1.30)(-0.89))x10(-10) based on three events in pion momentum region 211<P<229 MeV/c. At measured central value of ratio, had a signal-to-background 0.9.
We have observed six trimuon events produced by neutrinos in the new large-angle neutrino detector (NEULAND) at Fermilab with momenta and charges of almost all muons determined. The properties these strongly suggest that their origin is not hadronic but may be lepton sector.
We report the first observation of a charm-strange meson D(+)(sJ)(2632) at mass 2632.5+/-1.7 MeV/c(2) in data from SELEX, charm hadro-production experiment E781 Fermilab. This state is seen two decay modes, D(+)(s)eta and D0K+. In mode we observe peak with 101 events over combinatoric background 54.9 2635.4+/-3.3 MeV/c(2). There corresponding 21 6.9 2631.5+/-2.0 The width this <17 90% confidence level. relative branching ratio Gamma(D0K+)/Gamma(D(+)(s)eta) 0.14+/-0.06. mechanism that keeps...
Experiment E949 at Brookhaven National Laboratory studied the rare decay \$K^+\to\pi^+\nu\bar{\nu}$ and other processes with an exposure of $1.77\times 10^{12}$ $K^+$'s. The data were analyzed using a blind analysis technique yielding one candidate event estimated background $0.30\pm0.03$ events. Combining this result observation two events by predecessor experiment E787 gave branching ratio ${\calB}(K^+\to\pi^+\nu\bar{\nu})=(1.47^{+1.30}_{-0.89})\times 10^{-10}$, consistent Standard Model...
The characteristics of six trimuon events observed in the new large-angle neutrino detector at Fermilab are described. leptonic system appears to take an inordinate fraction incident energy if hadrons presumed be origin these events. A similar effect seems present dimuon previously observed. find a natural interpretation as products cascade decay lepton (the $M$ particle) through lower-mass neutral ${L}^{0}$ particle).
The MEGA experiment, which searched for the muon- and electron-number violating decay μ+→e+γ, is described. spectrometer system, calibrations, data taking procedures, analysis, sensitivity of experiment are discussed. most stringent upper limit on branching ratio, B(μ+→e+γ)<1.2×10−11 with 90% confidence, derived from a likelihood analysis.Received 6 November 2001DOI:https://doi.org/10.1103/PhysRevD.65.112002©2002 American Physical Society
The δ opioid antagonist H-Dmt-Tic-OH (2',6'-dimethyl-l-tyrosyl-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid) exhibits extraordinary receptor binding characteristics [Kiδ = 0.022 nM; Kiμ/Kiδ 150 000] and antagonism (pA2 8.2; Ke 5.7 nM). A change in chirality of Dmt at Cα (1, 2, 6, 8, 10, 13) curtailed parameters, while replacement its α-amino function by a methyl group (3) led to inactivity; Tyr-Tic analogues 4 11 weakly interacted with receptors. N-Alkylation H-Dmt-Tic-Ala-OH groups...
Twenty N- and/or C-modified Dmt-Tic analogues yielded similar K(i) values with either [(3)H]DPDPE (delta(1) agonist) or [(3)H]N, N(Me)(2)-Dmt-Tic-OH (delta antagonist). N-Methylation enhanced delta antagonism while N-piperidine-1-yl, N-pyrrolidine-1-yl, and N-pyrrole-1-yl were detrimental. Dmt-Tic-X (X = -NHNH(2), -NHCH(3), -NH-1-adamantyl, -NH-tBu, -NH-5-tetrazolyl) had high affinities (K(i) 0.16 to 1 nM) variable mu yield nonselective weakly mu-selective analogues. N,...