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Murray Moinester

Publications and source records attributed to Murray Moinester.

18 recordsLinked to original sources
arXiv2025

Disentangling the soil and atmospheric stress on carbon sequestration in a Mediterranean pine forest

Sequestration of atmospheric CO$_2$ in a Mediterranean semi-arid Aleppo Pine Forest (Pinus halepensis) close to the border of the semi-arid timberline was characterized and quantified under field conditions. Measurements of organic and inorganic CO$_2$ sequestration with gas exchange and stock counting approaches were made in both rainfed control (approximately 12$\%$ average annual soil moisture) and summer irrigated plots (approximately 24$\%$ annual average soil moisture), providing the opportunity to separate the effects of atmospheric water demand from soil water stress on the atmospheric CO$_2$ sequestration responses. Measurements yield an organic carbon sequestration (OCS) rate of approximately 550 g CO$_2$ m$^{-2}$ yr$^{-1}$, two-thirds in soil and one-third in biomass. In addition, measurements yield an inorganic carbon sequestration (ICS) rate of approximately 216 g CO$_2$ m$^{-2}$ yr$^{-1}$; via calcite (CaCO$_3$) precipitation in the soil due to root exhalation of CO$_2$ (60$\%$) and microbial activity (40$\%$). The drip irrigated plot showed approximately 3 times higher organic CO$_2$ sequestration than the control plot. The organic sequestration is divided equally between the soil and the biomass. For the irrigated plot, the inorganic CO$_2$ was approximately 1.8 times higher than that of the control plot. However, for inorganic CO$_2$ sequestration, the soil moisture would need to be maintained lower than that of the study plot to preclude dissolving precipitated calcite. For many drylands, irrigation could be achieved by using fossil water reserves. These measured values demonstrate the relatively high potential carbon sequestration in Mediterranean drylands forests under irrigated and non-irrigated conditions.

physics.geo-ph↗
arXiv2025

Tribute to Henry Primakoff: Chiral Perturbation Theory Tests via Primakoff Reactions

Consider high energy (GeV) beam particles scattering from the Coulomb field of a target nucleus (Z, A). The Coulomb field acts as a target of $\gamma^*$ virtual photons, with the target density proportional to Z$^2$. Henry Primakoff was the first to propose determining the lifetime of the $\pi^0$ meson by measuring the production cross section for the reaction $\gamma\gamma^* \rightarrow \pi^0$. This process occurs when a high-energy gamma-ray interacts with the Coulomb field. Quasi real exchanged photons ($\gamma^*$) are identified by isolating the sharp Coulomb peak at very low values of the squared four momentum transfer t to the target nucleus. The scattering cross section via one-photon exchange is proportional to the fine-structure constant $\alpha$ and inversely proportional to t$^2$. Since t is inversely related to the squared center-of-mass energy (s), it decreases rapidly as s increases. Consequently, despite the weakness of the electromagnetic interaction, the interaction amplitude can still be significant. We will first discuss Primakoff's scientific career and personal life. Next, we will review the Primakoff scattering experiments that measured the pion polarizability and the $\gamma\rightarrow\pi\pi\pi$ chiral anomaly amplitude at CERN COMPASS and the $\pi^0$ lifetime at Jefferson Laboratory (JLab). The data from these experiments are in good agreement with two-flavor (u, d) Chiral Perturbation Theory (ChPT) predictions. We explain that additional Primakoff measurements with kaons and $\eta$ mesons are needed to test how well three flavor (u, d, s) ChPT captures strange quark effects.

hep-ph↗
arXiv2024

Tests of Three-Flavor Chiral Perturbation Theory

We review experimental tests of three-flavor (u,d,s) chiral perturbation theory (ChPT). These include measurements of pion and kaon polarizabilities, the chiral anomaly amplitudes for processes such as $\gamma \rightarrow \pi\pi\pi$, $\gamma \rightarrow \pi\pi\eta$, and $\gamma \rightarrow KK\pi$; as well as the lifetimes of the neutral pion and eta. These observables are extracted primarily through ultra-peripheral Primakoff scattering of high-energy particles from virtual photons in the Coulomb field of nuclei. Comparing data to two-flavor and three-flavor predictions allows us to evaluate how well ChPT describes light meson dynamics and the role of the strange quark in spontaneous chiral symmetry breaking.

hep-ph↗
arXiv2024

Concrete and Lead Shielding Requirements for PET Facilities

We investigate shielding thickness requirements in concrete and lead walls for positron emission tomography (PET) facilities. F\textsuperscript{18}, the most commonly used PET radiotracer, emits two back-to-back 511 keV photons, necessitating effective shielding to protect hospital staff while patients are in treatment rooms and during their hospital stay. Photon transmission measurements were conducted through a standard Israeli B30 concrete wall (3 m high, 20 cm thick) using photons from an F\textsuperscript{18} source. A narrow-beam transmission coefficient of \( T = (3.0 \pm 1.0)\% \) was recorded with the source positioned 0.05 m from the wall, and the detector at distances of 0.05--3.0 m on the opposite side. When the source is 3 meters from the wall, photons within a 0.64 m radius circular disk (wide-beam) strike the wall. This produces a dose ``buildup'' effect, whereby photons striking within the disk reach the dosimeter after Compton scattering within the wall. The wide-beam transmission coefficient was measured as \( T = (8.8 \pm 1.8)\% \), corresponding to a buildup factor \( B = 4.0 \pm 0.8 \), consistent with Monte Carlo (MC) simulations \( B = 3.9 \pm 0.6 \), validating the simulation reliability for this specific setup. Note however that reliance solely on thick concrete walls presents construction challenges due to weight, space, and cost inefficiency. Since ordinary concrete effectively interacts only through Compton scattering, while lead walls interact via the photoelectric effect, lead is preferable for shielding. A 3.3 cm lead wall results in \( < 0.5\% \) transmission, and lead sheets can be supported by a 5 cm gypsum wall, optimizing shielding design. However, considering the environmental toxicity of lead, note that recent studies advocate the use of tungsten carbide.

physics.med-ph↗
arXiv2022

Potential Global Sequestration of Atmospheric Carbon Dioxide by Drylands Forestation

Drylands forestation offers the potential for significant long-term sequestration of atmospheric CO$_2$. We consider sequestration of organic and inorganic carbon by a planted semi-arid forest, based on carbon that originates from atmospheric CO$_2$. Measurements at Israels Yatir forest give a sequestration rate of $\sim$550 g CO$_2$ m$^{-2}$ yr$^{-1}$ as organic carbon in the trees biomass. The inorganic carbon precipitation rate gives an additional 216 g CO$_2$ m$^{-2}$ yr$^{-1}$ globally, via calcite (CaCO$_3$) precipitation in soil. This sequestration is due to a combination of microbial activity on organic soil carbon, and the formation of soil carbonic acid (H$_2$CO$_3$) that arises from the reaction of soil water with CO$_2$ exhaled from tree roots. Published estimates restrict the potential drylands surface available for sustainable forestation to $\sim$4.5 million km$^2$, only $\sim$10$\%$ of the global drylands. The dominant limitation is the apparent lack of water. However, immediately under many drylands, there are paleowaters (fossil water) that had recharged underlying aquifers during prior wetter climatic regimes. Conservatively, including fossil water, at least $\sim$9.0 million km$^2$ is available for afforestation. Measurements at Yatir show that drip irrigation to $\sim$18$\%$ average Soil Moisture (higher than the rainfed $\sim$12$\%$ SM) would double the organic carbon sequestration rate. In addition, the tree density could be increased, which would independently double the organic carbon sequestration rate. The potential total annual sequestration rate is then estimated as 20.0 Gt CO$_2$. Measurements at Israels Yatir forest give a sequestration rate of $\sim$20.0 Gt CO$_2$ yr$^{-1}$, divided between 14.0 Gt CO$_2$ yr$^{-1}$ (organic) and 6.0 Gt CO$_2$ yr$^{-1}$ (inorganic). This corresponds to $\sim$100$\%$ of the annual rate of atmospheric CO$_2$ increase.

physics.geo-ph↗
arXiv2022

Pion Polarizability 2022 Status Report

The electric ${\alpha}_{\pi}$ and magnetic ${\beta}_{\pi}$ charged pion Compton polarizabilities are of fundamental interest in the low-energy sector of quantum chromodynamics (QCD). They characterize the induced dipole moments of the pion during ${\gamma}{\pi}$ Compton scattering. Pion polarizabilities affect the shape of the ${\gamma}{\pi}$ Compton scattering angular distribution.The combination $({\alpha}_{\pi} - {\beta}_{\pi})$ was measured by: (1) CERN COMPASS via ${\pi} Z \rightarrow {\pi} Z {\gamma}$ radiative pion Primakoff scattering in the nuclear Coulomb field, (2) SLAC PEP Mark-II via two-photon production of pion pairs, ${\gamma} {\gamma} \rightarrow {\pi}^+ {\pi}^-$, and (3) Mainz Microtron MAMI via radiative pion photoproduction from the proton, ${\gamma} p \rightarrow {\gamma} {\pi}^+ n$. Ongoing and planned pion polarizability experiments (CERN COMPASS, BESIII at Beijing, JLab at Newport News) are also described. The Mark-II pion polarizability 95% confidence interval is approximately $0-11 \times 10^{-4} {fm}^{3}$, based on $({\alpha}_{\pi} - {\beta}_{\pi}) = (4.4 \pm 3.2) \times 10^{-4} {fm}^{3}$. The Mainz value $({\alpha}_{\pi} - {\beta}_{\pi}) = 11.6 \times 10^{-4} {fm}^{3}$ is excluded on the basis of a dispersion relations calculation which uses the Mainz value as input, and gives significantly too large ${\gamma} {\gamma} \rightarrow {\pi}^{0} {\pi}^{0}$ cross sections compared to DESY Crystal Ball data. To date, only the COMPASS polarizability measurement has acceptably small uncertainties. Its value $({\alpha}_{\pi} - {\beta}_{\pi}) = (4.0 \pm 1.8) \times 10^{-4} {fm}^{3}$ agrees well with the two-loop ChPT prediction $({\alpha}_{\pi} - {\beta}_{\pi}) = (5.7 \pm 1.0) \times 10^{-4} {fm}^{3}$, thereby strengthening the identification of the pion with the Goldstone boson of QCD.

hep-ph↗
arXiv2019

Compton Scattering off Pions and Electromagnetic Polarizabilities

The electric ($α_π$) and magnetic ($β_π$) Compton polarizabilities of both the charged and the neutral pion are of fundamental interest in the low-energy sector of quantum chromodynamics (QCD). Pion polarizabilities affect the shape of the $γπ\toγπ$ Compton scattering angular distribution at back scattering angles and $γγ\toππ$ absolute cross sections. Theory derivations are given of the $γπ\toγπ$ Compton scattering differential cross section, dispersion relations, and sum rules in terms of the polarizabilities. We review experimental charged and neutral polarizability studies and theoretical predictions. The $π^0$ polarizabilities were deduced from DESY Crystal Ball $γγ\toπ^0π^0$ data, but with large uncertainties. The charged pion polarizabilities were deduced most recently from (1) radiative pion Primakoff scattering $π^- Z \to π^-Zγ$ at CERN COMPASS, (2) two-photon pion pair production $γγ\toπ^+π^-$ at SLAC Mark II, and (3) radiative pion photoproduction $γp\toγπ^+ n$ from the proton at MAMI in Mainz. A stringent test of chiral perturbation theory (ChPT) is possible based on comparisons of precision experimental charged pion polarizabilities with ChPT predictions. Only the CERN COMPASS charged pion polarizability measurement has acceptably small uncertainties. Its value $α_{π^\pm}-β_{π^\pm} = (4.0\pm 1.8)\times 10^{-4}\,\text{fm}^3$ agrees well with the two-loop ChPT prediction $α_{π^\pm}-β_{π^\pm}=(5.7\pm 1.0)\times 10^{-4}\,\text{fm}^3$, strengthening the identification of the pion with the Goldstone boson of chiral symmetry breaking in QCD.

hep-ph↗
arXiv2018

Pion Polarizability Status Report

The electric $α_π$ and magnetic $β_π$ charged pion Compton polarizabilities are of fundamental interest in the low-energy sector of quantum chromodynamics (QCD).They are directly linked to the phenomenon of spontaneously broken chiral symmetry within QCD and to the dynamics of the pion-photon interaction.The combination ($α_π-β_π$) was measured by:(1) CERN COMPASS via radiative pion Primakoff scattering (Bremsstrahlung) in the nuclear Coulomb field, $π^- Z \rightarrow π^-Z γ$, (2) SLAC PEP Mark-II via two-photon production of pion pairs, $γγ\rightarrowπ^+π^-$, and (3) Mainz Microtron via radiative pion photoproduction from the proton, $γp\rightarrowγπ^+n$. COMPASS and Mark-II agree with one another:(1) $α_π-β_π=4.0\times 10^{-4}fm^3$, (2) $α_π-β_π=4.4 \times 10^{-4}fm^3$. The Mainz value (3) $α_π-β_π=11.6 \times 10^{-4}fm^3$ is excluded here because a dispersion relations calculation using the Mainz value as input gives significantly too large $γγ \rightarrow π^0π^0$ cross sections compared to DESY Crystal Ball data. COMPASS and Mark-II values agree well with the two-loop chiral perturbation theory ChPT prediction $α_π-β_π=5.7\times10^{-4}fm^3$, thereby strengthening the identification of the pion with the Goldstone boson of QCD.

hep-ph↗
arXiv2017

Sequestration of atmospheric carbon dioxide as inorganic carbon in the unsaturated zone under semi-arid forests

Inorganic carbon, in the form of allogenic (transported) and pedogenic (soil) carbonates in semi-arid soils, may comprise an important carbon sink. Carbon dioxide, CO2, originating from the atmosphere and exhaled by tree roots into the soil, may be hydrated by soil water within the unsaturated zone (USZ) of semi-arid soils to produce the carbonic acid (H2CO3) solutes HCO3- bicarbonate and H+ Hydrogen ion. This H+ may then dissolve relict soil CaCO3 carbonate (calcite), to release Ca+2 calcium cations and more HCO3- bicarbonate. When conditions allow, one mole of Ca+2 and two moles of HCO3- combine to precipitate one mole of calcite, and to release one mole of CO2: Ca+2 + 2HCO3- --> CaCO3 + CO2 + H2O. However, it has been claimed that such carbonates do not sequester significant amounts of present day atmospheric CO2. The reasons given were that they originate in part from the pre-existing limestone; and that for every mole of calcite precipitated, one mole of CO2 may be liberated to the atmosphere. It was argued that only if the Ca+2 cation is derived from a non-carbonate source can sequestration be assumed. We have tested these assumptions under field conditions at two semi-arid sites in Israel. We found that bicarbonate, originating from root exhalation, is depleted and is incorporated within the USZ as carbonates precipitate. Thus, a net sequestration of atmospheric CO2 does occur under semi-arid forests. Moreover, most of the CO2 liberated in the precipitation reaction may remain in the soil. And Ca+2 in the sediment may also be supplied from sources other than pre-existing calcite. Forestation can therefore augment pedogenic carbonate formation. By extrapolating our data globally, we suggest that worldwide semi-arid forests (existing and to be planted) may sequester 5-20% of the current annual anthropogenic increase of atmospheric carbon dioxide as pedogenic carbonate.

physics.geo-ph↗
arXiv2003

Hybrid Meson Production via Pion Scattering from the Nuclear Coulomb Field

The CERN COMPASS experiment can use 100-280 GeV pion and kaon beams and magnetic spectrometers and calorimeters to measure Hybrid (mixed quark-gluon) meson production cross sections in the Primakoff scattering of high energy pions and kaons from virtual photons in the Coulomb field of High-Z targets. There are many advantages to studying such processes via the Primakoff reactions pi- gamma --> Hybrid --> rho pi, eta pi, eta' pi, pi b1, pi f1, and similar reactions with a K- beam. Such data should provide significant input for gaining a better understanding of non-perturbative QCD. A brief description and update of this program is presented.

hep-ex↗
arXiv2003

Pion and Kaon Polarizabilities at CERN COMPASS

The electric alpha and magnetic beta pion Compton polarizabilities characterize the pion's deformation in the electromagnetic field of the gamma during gamma-pi Compton scattering. The pion polarizabilities are key observables, and provide stringent tests of our understanding of chiral symmetry, its spontaneous breakdown, the role of explicit symmetry breaking in QCD. The chi_PT effective Lagrangian, using data from radiative pion beta decay, predicts the pion electric and magnetic polarizabilities alpha = -beta = 2.7 +- 0.4, in standard polarizability units. The polarizabilities deduced by Antipov et al. in their low statistics Primakoff experiment (~ 7000 events) were about three times larger than this prediction. For pion polarizability, gamma-pi scattering will be measured in CERN COMPASS via radiative pion Primakoff scattering (pion Bremsstrahlung) in the nuclear Coulomb field: pi + Z --> pi' + gamma + Z; equivalent to gamma + pi --> gamma + pi Compton scattering for laboratory gamma's of order 1 GeV incident on a target pion at rest. The pion polarizabilities are determined by their effect on the shape of the measured gamma-pi Compton scattering angular distribution. One can expect from COMPASS a total measurement uncertainty for alpha of order 0.4 for the pion polarizability. COMPASS can also carry out a first measurement of Kaon ploarizabilities. New high precision pion and Kaon polarizability measurements via radiative pion and Kaon scattering data from COMPASS will provide important new tests of the QCD chiral dynamics polarizability prediction.

hep-ex↗
arXiv2002

First Observation of Doubly Charmed Baryons

The SELEX experiment (E781) at Fermilab has observed two statistically compelling high mass states near 3.6 GeV/c^2, decaying to Lambda_c+ K- pi+ and Lambda_c+ K- pi+ pi+. These final states are Cabibbo-allowed decay modes of doubly charmed baryons $Ξ_{cc}^+$ and $Ξ_{cc}^{++}$, respectively. The masses are in the range expected from theoretical considerations, but the spectroscopy is surprising. SELEX also has weaker preliminary evidence for a state near 3.8 GeV/$\rm{c}^2$, a high mass state decaying to Lambda_c+ K- pi+ pi+, possibly an excited $Ξ_{cc}^{++}$ (ccu*). Data are presented and discussed.

hep-ex↗
arXiv2002

Pion Polarizabilities at CERN COMPASS

The electric alpha and magnetic beta pion Compton polarizabilities characterize the pion's deformation in the electromagnetic field of the gamma during gamma-pi Compton scattering. The chi_PT effective Lagrangian, using data from radiative pion beta decay, predicts the pion electric and magnetic polarizabilities alpha = -beta = 2.7 +- 0.4. The polarizabilities deduced by Antipov et al. in their low statistics Primakoff experiment (~ 7000 events) were about three times larger than this prediction. For pion polarizability, gamma-pi scattering will be measured in CERN COMPASS via radiative pion Primakoff scattering (pion Bremsstrahlung) in the nuclear Coulomb field: pi + Z --> pi' + gamma + Z; equivalent to gamma + pi --> gamma + pi Compton scattering for laboratory gamma's of order 1 GeV incident on a target pi at rest. The pion polarizabilities are determined by their effect on the shape of the measured gamma-pi Compton scattering angular distribution. One can expect from COMPASS a total measurement uncertainty for alpha, of order 0.4. New high precision pion polarizability measurements via radiative pion scattering data from COMPASS will provide important new tests of the QCD chiral dynamics polarizability prediction.

hep-ex↗
arXiv2001

Color Transparency at COMPASS - Feasibility Study

We examine the potential of the COMPASS experiment at CERN to study color transparency via exclusive vector meson production in hard muon-nucleus scattering. It is demonstrated that COMPASS has high sensitivity to test this important prediction of perturbative QCD.

hep-ex↗
arXiv2000

Pion Polarizabilities and Hybrid Meson Structure at CERN COMPASS

CERN COMPASS can investigate pion-photon interactions, to achieve a unique Primakoff Coulomb physics program, centered on pion polarizability and hybrid meson structure studies. COMPASS uses 100-280 GeV beams (muon, pion) and a virtual photon target, and magnetic spectrometers and calorimeters to measure the complete kinematics of pion-photon reactions. The COMPASS experiment is scheduled to begin data runs in 2001. Pion polarizabilities and hybrid mesons can be studied via the Primakoff reactions pion + gamma ---> pion + gamma and pion + gamma ---> Hybrid. The electric (alpha) and magnetic (beta) pion and Kaon polarizabilities characterize their deformation in an electromagnetic field, as occurs during gamma-pion Compton scattering. They depend on the rigidity of their internal structures as composite particles, and are therefore important quantities to test the validity of theoretical models. The polarizability measurement will provide an important new test of QCD chiral dynamics. The studies of quark-antiquark-gluon hybrid mesons would improve our understanding of these exotic mesons. COMPASS may improve previous Primakoff polarizability and Hybrid studies by two to three orders of magnitude. Appendixes A (Pion and Kaon Polarizabilities at COMPASS) and B (Hybrid Meson Structure at COMPASS) of this contribution include evaluations submitted to the APS DNP Town Meeting White Paper Committee. These summarize (1) the fundamental scientific issues addressed, (2) major achievements since the last DNP long range plan, (3) the short and long term U.S. outlook, (4) comparison of U.S. and global effort, (5) other issues.

hep-ex↗
arXiv2000

Hybrid Meson Structure at COMPASS

We describe a pion physics program attainable with the CERN COMPASS spectrometer, involving tracking detectors and an electromagnetic calorimeter. COMPASS can realize state-of-the-art pion beam hybrid meson and meson radiative transition studies. We review here the physics motivation for this program. We describe the beam, detector, trigger requirements, and hardware/software requirements for this program. The triggers for all this hybrid meson physics can be implemented for simultaneous data taking. We will investigate hybrid meson production via pion-photon Primakoff and pion-Pomeron diffractive interactions. We will determine new properties of quark-antiquark-gluon hybrid mesons, using unique production methods, to improve our understanding of these exotic mesons. The CERN COMPASS experiment uses 100-280 GeV beams (muon, pion), and magnetic spectrometers and calorimeters, to measure the complete kinematics of pion-photon and pion-Pomeron reactions. The COMPASS experiment is currently under construction, and scheduled to begin data runs in 2001. We carry out simulation studies to optimize the beam, detector, trigger, and hardware/software for achieving high statistics data with low systematic uncertainties in the hybrid meson component of this program. We will improve previous Primakoff Hybrid studies by three orders of magnitude. We implement special detectors and triggers for hybrid meson production reactions. We propose to prepare for these COMPASS pion beam hybrid studies by setting up with muon beam tests.

hep-ex↗
arXiv1999

Exclusive meson production at COMPASS

We explore the feasibility to study exclusive meson production (EMP) in hard muon-proton scattering at the COMPASS experiment. These measurements constrain the off-forward parton distributions (OFPD's) of the proton, which are related to the quark orbital contribution to the proton spin.

hep-ph↗