A5018016903- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Particle physics theoretical and experimental studies
- Nuclear physics research studies
- Atomic and Subatomic Physics Research
- Nuclear reactor physics and engineering
- Photoreceptor and optogenetics research
- Stochastic processes and statistical mechanics
- Quantum, superfluid, helium dynamics
- Particle Accelerators and Free-Electron Lasers
- Photosynthetic Processes and Mechanisms
- Particle Detector Development and Performance
- Statistical Methods and Bayesian Inference
- Markov Chains and Monte Carlo Methods
- Advanced NMR Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Dark Matter and Cosmic Phenomena
- Atomic and Molecular Physics
- Laser-Matter Interactions and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Superconducting Materials and Applications
- Mechanical and Optical Resonators
- CCD and CMOS Imaging Sensors
- Spectroscopy and Laser Applications
- Fusion materials and technologies
Argonne National Laboratory
2020-2025
Brookhaven National Laboratory
2023-2025
Ball State University
2023-2024
Forschungszentrum Jülich
2014-2024
Wuhan University of Science and Technology
2024
Variable Energy Cyclotron Centre
2020-2024
Wayne State University
2020-2024
Yale University
2020-2024
Frankfurt Institute for Advanced Studies
2021-2024
Central China Normal University
2020-2024
A next-generation medium-energy gamma-ray telescope targeting the MeV range would address open questions in astrophysics regarding how extreme conditions accelerate cosmic-ray particles, produce relativistic jet outflows, and more. One concept, AMEGO-X, relies upon mission-enabling CMOS Monolithic Active Pixel Sensor silicon chip AstroPix. AstroPix is designed for space-based use, featuring low noise, power consumption, high scalability. Desired performance of device include an energy...
This paper presents the successful application of a phase-lock feedback system to maintain resonance condition radio frequency (rf) spin rotator (specifically, an rf Wien filter) with respect 120 kHz precession in Cooler Synchrotron (COSY) storage ring. Real-time monitoring and filter signal allows relative phase between two be stabilized at arbitrary setpoint. The compensates for deviations by adjusting and/or as needed. With this method, variation demand standard deviation...
This Letter reports the successful use of feedback from a spin polarization measurement to revolution frequency $0.97\text{ }\text{ }\mathrm{GeV}/c$ bunched and polarized deuteron beam in Cooler Synchrotron (COSY) storage ring order control both precession rate ($\ensuremath{\approx}121\text{ }\mathrm{kHz}$) phase horizontal component. Real time synchronization with radio (rf) solenoid made possible rotation out plane, yielding demonstration method manipulate polarization. In particular,...
We report on a high-statistics measurement of the most basic double pionic fusion reaction $\vec{n}p \to d\pi^0\pi^0$ over energy region $d^*(2380)$ resonance by use polarized deuteron beam and observing in quasifree scattering mode. The measurements were performed with WASA detector setup at COSY. data reveal substantial analyzing powers confirm conclusions about $d^*$ obtained from unpolarized measurements. also previous under complementary kinematic conditions.
The stable spin direction of polarized particles in a storage ring was determined first experimentally, through an accurate measurement the tune and its response to longitudinal magnetic fields.
Time-resolved pump-and-probe experiments of reaction centers the purple bacterium Rhodobacter sphaeroides (R26) in mid-IR region between 1000 and 1800 cm-1 are recorded with a time resolution 300-400 fs. The difference spectra states P*, P+HA-, P+QA- respect to ground state P predominantly reflect changes special pair. They show positive negative bands due distinct vibrational modes superimposed on broad background enhanced absorption. A number certain can be assigned pair P,...
Exclusive measurements of the quasi-free pn→ppπ− and pp→ppπ0 reactions have been performed by means pd collisions at Tp=1.2 GeV using WASA detector setup COSY. Total differential cross sections obtained covering energy region Tp=0.95–1.3GeV (s=2.3–2.46 GeV), which includes regions Δ(1232), ⁎N⁎(1440) ⁎d⁎(2380) resonance excitations. From these isoscalar single-pion production has extracted, for data existed so far only below Tp=1 GeV. We observe a substantial increase this section around 1...
The proposed method exploits charged particles confined as a storage ring beam (proton, deuteron, possibly $^3$He) to search for an intrinsic electric dipole moment (EDM) aligned along the particle spin axis. Statistical sensitivities could approach 10$^{-29}$ e$\cdot$cm. challenge will be reduce systematic errors similar levels. adjusted preserve polarisation, initially parallel velocity, times in excess of 15 minutes. Large radial fields, acting through EDM, rotate polarisation from...
A spectrometer system is presented for time-resolved probing in the midinfrared between 5 and 11 microm with a temporal resolution of better than 400 fs. Multichannel detection HgCdTe detector arrays consisting ten elements combination high repetition rate permits one to record weak absorbance changes an accuracy 0.1 mOD.
The WASA-at-COSY experiment has collected $3\ifmmode\times\else\texttimes\fi{}{10}^{7}$ events with $\ensuremath{\eta}$ mesons produced via the reaction $pd\ensuremath{\rightarrow}^{3}\mathrm{He}\phantom{\rule{0.16em}{0ex}}\ensuremath{\eta}$ at $\mathrm{T}=1.0\phantom{\rule{4pt}{0ex}}\mathrm{GeV}$. Using this data set, we evaluate branching ratios of decays $\ensuremath{\eta}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}\ensuremath{\gamma}$,...
The light induced isomerisation reaction of the protonated Schiff base retinal with butylamine was studied in solution by subpicosecond infrared spectroscopy spectral range CC, CC and CNH+ stretching modes. Upon heating internal S1 → S0 conversion process, vibrationally hot molecules are formed which characterized pronounced red-shifts frequency shifts can be used to estimate an intramolecular temperature chromophore 550 K immediately after transition.
Using the production reactions $pd\to {}^3\mbox{He}\,\omega$ and $pp\to pp\omega$, Dalitz plot distribution for $\omega \to \pi^+ \pi^- \pi^0$ decay is studied with WASA detector at COSY, based on a combined data sample of $ (4.408\pm 0.042) \times 10^4$ events. The density parametrised by product $P$-wave phase space polynomial expansion in normalised polar variables $Z$ $\phi$. For first time, deviation from pure observed significance $4.1\sigma$. linear term $1+2\alpha Z$, $\alpha$...
Exclusive measurements of the quasifree pp→ppπ+π− reaction have been carried out at WASA@COSY by means pd collisions Tp=1.2 GeV. Total and differential cross sections extracted covering energy region Tp=1.08–1.36 GeV, which is N∗(1440) Δ(1232)Δ(1232) resonance excitations. Calculations describing these excitations t-channel meson exchange are variance with measured underpredict substantially experimental total section. An isotensor ΔN dibaryon I(JP)=2(1+) produced associatedly a pion able to...
In this paper, we demonstrate the connection between a magnetic storage ring with additional sextupole fields set so that x and y chromaticities vanish maximizing of lifetime in-plane polarization (IPP) for 0.97-GeV/c deuteron beam. The IPP magnitude was measured by continuously monitoring down-up scattering asymmetry (sensitive to sideways polarization) in an in-beam, carbon-target polarimeter unfolding precession due anomaly deuteron. optimum operating conditions long were made scanning...
Various theoretical calculations based on QCD or hadronic interactions predict that in addition to the recently observed dibaryon resonance ⁎d⁎(2380) with I(JP)=0(3+) there should also exist a mirrored quantum numbers I(JP)=3(0+). We report here search for such NN-decoupled state data pp→ppπ+π+π−π− reaction. Since no clear-cut evidence has been found, we give upper limits production cross section of mass range 2280–2500 MeV.
New data on both total and differential cross sections of the production η mesons in proton–deuteron fusion to He3η excess energy region 13.6MeV≤Qη≤80.9MeV are presented. These have been obtained with WASA-at-COSY detector setup located at Forschungszentrum Jülich, using a proton beam 15 different momenta between pp=1.60GeV/c pp=1.74GeV/c. While significant structure section is observed 20MeV≲Qη≲60MeV, previously reported sharp variation around Qη≈50MeV cannot be confirmed. Angular...
The excitation function for the $pd\rightarrow$ $d p \pi^{0}$ reaction has been measured by WASA-at-COSY experiment with aim of searching $^{3}\hspace{-0.03cm}\mbox{He}$-$\eta$ mesic nuclei. measurement in vicinity $\eta$ meson production was performed using a ramped proton beam. data analysis and interpretation carried out assumption that $\eta$-mesic Helium decays via formation an intermediate N$^{*}$(1535) resonance. No direct signal nucleus is observed function. We determine new improved...
We report on the investigation of rare decay $\eta\rightarrow\pi^0+\text{e}^++\text{e}^-$ which is interest to study both $C$ violation in electromagnetic interaction and search for contributions from physics beyond Standard Model, since allowed via a two-photon intermediate state strongly suppressed. The experiment has been performed using WASA-at-COSY installation, located at COSY accelerator Forschungszentrum J\"ulich, Germany. In total $3\times10^7$ events reaction...
This paper reports the first simultaneous measurement of horizontal and vertical components polarization vector in a storage ring under influence radio frequency (rf) solenoid. The experiments were performed at Cooler Synchrotron COSY J\"ulich using polarized, bunched $0.97\,\textrm{GeV/c}$ deuteron beam. Using new spin feedback system, we set initial phase difference between solenoid field precession to predefined value. system was then switched off, allowing change over time, on rotate...
We report on the experimental search for bound state of an η meson and He3 nucleus performed using WASA-at-COSY detector setup. In order to η-mesic decay, pd→3He2γ pd→3He6γ channels have been analysed. These reactions manifest direct decay in a nucleus. This non-mesonic channel has considered first time. When taking into account only statistical errors, obtained excitation functions reveal slight indication possible signal corresponding 3He-η width Γ above 20 MeV binding energy Bs between 0...
We investigated coherent betatron oscillations of a deuteron beam in the storage ring cooler synchrotron and ring, excited by detuned rf Wien filter (WF). The were detected conventional position monitors. With currently available apparatus, we show that oscillation amplitudes down to $1\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ can be detected. interpretation response stored WF is based on simulations evolution lattice realistic time-dependent 3D field maps WF. Future measurements electric...
Abstract A measurement of vector analyzing powers in elastic deuteron-carbon scattering has been performed at the Cooler Synchrotron COSY Forschungszentrum Jülich, Germany. Seven kinetic beam energies between 170 and 380 MeV have used. vector-polarized from a polarized deuteron source was injected, accelerated to final desired energy stored COSY. thin needle-shaped diamond strip used as carbon target, onto which slowly steered. Elastically scattered deuterons were identified forward...
A calorimetric polarimeter based on inorganic LYSO scintillators is described. It has been designed for use in a storage ring to search electric dipole moments (EDM) of charged particles such as the proton and deuteron. Its development first was Cooler Synchrotron (COSY) at Forschungszentrum Jülich with 0.97 GeV/c polarized deuterons, particle energy suitable an EDM search. The requires high efficiency, large analyzing power, stable operating characteristics. With typical beam momenta about...