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Full-Text Articles in Physics

First Measurement Of Hard Exclusive 𝛑⁻Δ⁺⁺ Electroproduction Beam-Spin Asymmetries Off The Proton, S. Diehl, N. Trotta, K. Joo, P. Achenbach, Z. Akbar, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, A. Bianconi, A. S. Biselli, F. Bossù, K.-T. Brinkman, M. Zurek, Et Al., Clas Collaboration Jan 2023

First Measurement Of Hard Exclusive 𝛑⁻Δ⁺⁺ Electroproduction Beam-Spin Asymmetries Off The Proton, S. Diehl, N. Trotta, K. Joo, P. Achenbach, Z. Akbar, W. R. Armstrong, H. Atac, H. Avakian, L. Baashen, N. A. Baltzell, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, F. Benmokhtar, A. Bianconi, A. S. Biselli, F. Bossù, K.-T. Brinkman, M. Zurek, Et Al., Clas Collaboration

Physics Faculty Publications

The polarized cross-section ratio σLT′/σ0 from hard exclusive πΔ++ electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2  GeV/10.6  GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5  GeV2 up to 7  GeV2. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ++ transition generalized parton …


Dirac Dark Matter, Neutrino Masses, And Dark Baryogenesis, Diego Restrepo, Andrès Rivera, Walter Tangarife Sep 2022

Dirac Dark Matter, Neutrino Masses, And Dark Baryogenesis, Diego Restrepo, Andrès Rivera, Walter Tangarife

Physics: Faculty Publications and Other Works

We present a gauged baryon number model as an example of models where all new fermions required to cancel out the anomalies help to solve phenomenological problems of the standard model (SM). Dark fermion doublets, along with the isosinglet charged fermions, in conjunction with a set of SM-singlet fermions, participate in the generation of small neutrino masses through the Dirac-dark Zee mechanism. The other SM-singlets explain the dark matter in the Universe, while their coupling to an inert singlet scalar is the source of the CP violation. In the presence of a strong first-order electroweak phase transition, this “dark” CP …


Measurement Of The B± Meson Nuclear Modification Factor In Pb-Pb Collisions At Snn =5.02 Tev, A. M. Sirunyam, A. R. Tumasyan, Adam Wolfgang, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Toohin S. Roy, Francisco X. Yumiceva Oct 2017

Measurement Of The B± Meson Nuclear Modification Factor In Pb-Pb Collisions At Snn =5.02 Tev, A. M. Sirunyam, A. R. Tumasyan, Adam Wolfgang, Marc M. Baarmand, Vallary Bhopatkar, Stefano Colafranceschi, Marcus Hohlmann, Daniel Noonan, Toohin S. Roy, Francisco X. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

The differential production cross sections of B± mesons are measured via the exclusive decay channels B±→J/ψK±→μ+μ-K± as a function of transverse momentum in pp and Pb-Pb collisions at a center-of-mass energy sNN=5.02 TeV per nucleon pair with the CMS detector at the LHC. The pp(Pb-Pb) data set used for this analysis corresponds to an integrated luminosity of 28.0 pb-1 (351 μb-1). The measurement is performed in the B± meson transverse momentum range of 7 to 50 GeV/c, in the rapidity interval |y|<2.4. In this kinematic range, a strong suppression of the production cross section by about a factor of 2 is observed in the Pb-Pb system in comparison to the expectation from pp reference data. These results are found to be roughly compatible with theoretical calculations incorporating beauty quark diffusion and energy loss in a quark-gluon plasma. © 2017 CERN, for the CMS Collaboration. Published by the American Physical Society under the terms of the «https://creativecommons.org/licenses/by/4.0/» Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.


A Proposal On Culling & Filtering A Coxeter Group For 4d, N = 1 Spacetime Susy Representations: Revised, D. E. A. Gates, S. James Gates, Kory Stiffler Aug 2016

A Proposal On Culling & Filtering A Coxeter Group For 4d, N = 1 Spacetime Susy Representations: Revised, D. E. A. Gates, S. James Gates, Kory Stiffler

Dartmouth Scholarship

We present an expanded and detailed discussion of the mathematical tools required to cull and filter representations of the Coxeter Group BC 4 into providing bases for the construction of minimal off-shell representations of the 4D, N" role="presentation" style="box-sizing: border-box; display: inline-table; line-height: normal; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">NN = 1 spacetime supersymmetry algebra.


Transverse Momentum Dependent (Tmd) Parton Distribution Functions: Status And Prospects, R. Angeles-Martinez, A. Bacchetta, I. I. Balitsky, D. Boer, M. Boglione, R. Boussarie, F. A. Ceccopieri, I. O. Cherednikov, P. Connor, M. G. Echevarria, G. Ferrera, J. Grados Luyando, F. Hautmann, H. Jung, T. Kasemets, K. Kutak, J. P. Lansberg, A. Lelek, G. Lykasov, J. D. Madrigal Martinez, P. J. Mulders, E. R. Nocera, E. Petreska, C. Pisano, R. Plaċakyte, V. Radescu, M. Radici, G. Schnell, I. Scimemi, A. Signori, L. Szymanowski, S. Taheri Monfared, F.F. Van Der Veken, H. J. Van Haevermaet, P. Van Mechelen, A. A. Vladimirov, S. Wallon Jan 2015

Transverse Momentum Dependent (Tmd) Parton Distribution Functions: Status And Prospects, R. Angeles-Martinez, A. Bacchetta, I. I. Balitsky, D. Boer, M. Boglione, R. Boussarie, F. A. Ceccopieri, I. O. Cherednikov, P. Connor, M. G. Echevarria, G. Ferrera, J. Grados Luyando, F. Hautmann, H. Jung, T. Kasemets, K. Kutak, J. P. Lansberg, A. Lelek, G. Lykasov, J. D. Madrigal Martinez, P. J. Mulders, E. R. Nocera, E. Petreska, C. Pisano, R. Plaċakyte, V. Radescu, M. Radici, G. Schnell, I. Scimemi, A. Signori, L. Szymanowski, S. Taheri Monfared, F.F. Van Der Veken, H. J. Van Haevermaet, P. Van Mechelen, A. A. Vladimirov, S. Wallon

Physics Faculty Publications

We review transverse momentum dependent (TMD) parton distribution functions, their application to topical issues in high-energy physics phenomenology, and their theoretical connections with QCD resummation, evolution and factorization theorems. We illustrate the use of TMDs via examples of multi-scale problems in hadronic collisions. These include transverse momentum qT spectra of Higgs and vector bosons for low qT, and azimuthal correlations in the production of multiple jets associated with heavy bosons at large jet masses. We discuss computational tools for TMDs, and present the application of a new tool, TMDLIB, to parton density fits and parameterizations.


Measurement Of The Emc Effect In The Deuteron, K. A. Griffioen, J. Arrington, M. E. Christy, R. Ent, N. Kalantarians, C. E. Keppel, S E. Kuhn Jan 2015

Measurement Of The Emc Effect In The Deuteron, K. A. Griffioen, J. Arrington, M. E. Christy, R. Ent, N. Kalantarians, C. E. Keppel, S E. Kuhn

Physics Faculty Publications

We determined the structure function ratio RdEMC=Fd2/(Fn2+Fp2) from recently published Fn2/Fd2 data taken by the BONuS experiment using CLAS at Jefferson Lab. This ratio deviates from unity, with a slope dRdEMC/dx=−0.10 ± 0.05 in the range of Bjorken x from 0.35 to 0.7, for invariant mass W>1.4 GeV and Q2>1 GeV2 . The observed EMC effect for these kinematics is consistent with conventional nuclear physics models that include off-shell corrections, as well as with empirical analyses …


Gravitational Origin Of The Weak Interaction's Chirality, Stephon Alexander, Antonino Marcianò, Lee Smolin Mar 2014

Gravitational Origin Of The Weak Interaction's Chirality, Stephon Alexander, Antonino Marcianò, Lee Smolin

Dartmouth Scholarship

We present a new unification of the electro-weak and gravitational interactions based on the joining the weak SU(2) gauge fields with the left handed part of the space- time connection, into a single gauge field valued in the complexification of the local Lorentz group. Hence, the weak interactions emerge as the right handed chiral half of the space-time connection, which explains the chirality of the weak interaction. This is possible, because, as shown by Plebanski, Ashtekar, and others, the other chiral half of the space-time connection is enough to code the dynamics of the gravitational degrees of freedom. This unification …


Beam-Spin Asymmetries From Semi-Inclusive Pion Electroproduction, K. P. Adhikari, M. J. Amaryan, C. Hyde, S. Koirala, S. E. Kuhn, L. B. Weinstein, Et Al., The Clas Collaboration Jan 2014

Beam-Spin Asymmetries From Semi-Inclusive Pion Electroproduction, K. P. Adhikari, M. J. Amaryan, C. Hyde, S. Koirala, S. E. Kuhn, L. B. Weinstein, Et Al., The Clas Collaboration

Physics Faculty Publications

We have measured the moment Asin ɸLU corresponding to the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering. Asin ɸLU is a twist-3 quantity providing information about quark-gluon correlations. Data were taken with the CLAS Spectrometer at Jefferson Lab using a 5.498 GeV longitudinally polarized electron beam and an unpolarized liquid hydrogen target. All three pion channels (π+0 and π-) were measured simultaneously over a large range of kinematics within the virtuality range Q2 ≈ 1.0- 4.5 GeV2. The observable was measured with better than 1% statistical …


Inflation In (Super-)Renormalizable Gravity, Fabio Briscese, Antonino Marcianò, Leonardo Modesto, Emmanuel N. Saridakis Apr 2013

Inflation In (Super-)Renormalizable Gravity, Fabio Briscese, Antonino Marcianò, Leonardo Modesto, Emmanuel N. Saridakis

Dartmouth Scholarship

We investigate a (super-)renormalizable and ghost-free theory of gravity, showing that under a natural (exponential) ansatz of the form factor and a suitable truncation it can give rise to the Starobinsky inflationary theory in cosmological frameworks, and thus offering a theoretical justification of its origin. We study the corresponding inflationary evolution and we examine the generation of curvature perturbations, adapting the f(R)-like equations in a symmetry-reduced FLRW metric. Furthermore, we analyze how the ultraviolet regime of a simply renormalizable and unitary theory of gravity is also compatible with the Starobinsky action, and hence we show that such a theory could …


Gauge Field Preheating At The End Of Inflation, J. Tate Deskins, John T. Giblin Jr., Robert R. Caldwell Jan 2013

Gauge Field Preheating At The End Of Inflation, J. Tate Deskins, John T. Giblin Jr., Robert R. Caldwell

Dartmouth Scholarship

Here we consider the possibility of preheating the Universe via the parametric amplification of a massless, U(1) abelian gauge field. We assume that the gauge field is coupled to the inflaton via a conformal factor with one free parameter. We present the results of high-resolution three-dimensional simulations of this model and show this mechanism efficiently preheats the Universe to a radiation-dominated final state.


Information Content Of Spontaneous Symmetry Breaking, Marcelo Gleiser, Nikitas Stamatopoulos Aug 2012

Information Content Of Spontaneous Symmetry Breaking, Marcelo Gleiser, Nikitas Stamatopoulos

Dartmouth Scholarship

We propose a measure of order in the context of nonequilibrium field theory and argue that this measure, which we call relative configurational entropy (RCE), may be used to quantify the emergence of coherent low-entropy configurations, such as time-dependent or time-independent topological and nontopological spatially extended structures. As an illustration, we investigate the nonequilibrium dynamics of spontaneous symmetry breaking in three spatial dimensions. In particular, we focus on a model where a real scalar field, prepared initially in a symmetric thermal state, is quenched to a broken-symmetric state. For a certain range of initial temperatures, spatially localized, long-lived structures known …


Deformed Lorentz Symmetry And Relative Locality In A Curved/Expanding Spacetime, Giovanni Amelino-Camelia, Antonino Marcianò, Marco Matassa, Giacomo Rosati Jun 2012

Deformed Lorentz Symmetry And Relative Locality In A Curved/Expanding Spacetime, Giovanni Amelino-Camelia, Antonino Marcianò, Marco Matassa, Giacomo Rosati

Dartmouth Scholarship

The interest of part of the quantum-gravity community in the possibility of Planck-scale-deformed Lorentz symmetry is also fueled by the opportunities for testing the relevant scenarios with analyses, from a signal-propagation perspective, of observations of bursts of particles from cosmological distances. In this respect the fact that so far the implications of deformed Lorentz symmetry have been investigated only for flat (Minkowskian) spacetimes represents a very significant limitation, since for propagation over cosmological distances the curvature/expansion of spacetime is evidently tangible. We here provide a significant step toward filling this gap by exhibiting an explicit example of Planck-scale-deformed relativistic symmetries …


Could Any Black Holes Be Produced At The Lhc?, Jonas R. Mureika, Piero Nicolini, Euro Spallucci Apr 2012

Could Any Black Holes Be Produced At The Lhc?, Jonas R. Mureika, Piero Nicolini, Euro Spallucci

Physics Faculty Works

We introduce analytical quantum gravity modifications of the production cross section for terascale black holes by employing an effective ultraviolet cut off l. We find the new cross sections approach the usual "black disk" form at high energy, while they differ significantly near the fundamental scale from the standard increase with respect to s. We show that the heretofore discontinuous step function used to represent the cross section threshold can realistically be modeled by two functions representing the incoming and final parton states in a high energy collision. The growth of the cross section with collision energy is …


Measurement Of Exclusive Πº Electroproduction Structure Functions And Their Relationship To Transverse Generalized Parton Distributions, Clas Collaboration, K. P. Adhikari, M. J. Amaryan, R. P. Bennett, S. Koirala, S. E. Kuhn, M. Mayer, L. B. Weinstein, I. Bedlinsky, V. Kubarovsky Jan 2012

Measurement Of Exclusive Πº Electroproduction Structure Functions And Their Relationship To Transverse Generalized Parton Distributions, Clas Collaboration, K. P. Adhikari, M. J. Amaryan, R. P. Bennett, S. Koirala, S. E. Kuhn, M. Mayer, L. B. Weinstein, I. Bedlinsky, V. Kubarovsky

Physics Faculty Publications

Exclusive π0 electroproduction at a beam energy of 5.75 GeV has been measured with the Jefferson Lab CLAS spectrometer. Differential cross sections were measured at more than 1800 kinematic values in Q2, xB , t , and ϕπ , in the Q2 range from 1.0 to 4.6  GeV2 , −t up to 2  GeV2 , and xB from 0.1 to 0.58. Structure functions σT+ϵσL , σTT , and σLT were extracted as functions of t for each of 17 combinations of Q2 and xB . …


Double Ionization Of Helium By Highly-Charged-Ion Impact Analyzed Within The Frozen-Correlation Approximation, Marcelo F. Ciappina, Tom Kirchner, Michael Schulz Sep 2011

Double Ionization Of Helium By Highly-Charged-Ion Impact Analyzed Within The Frozen-Correlation Approximation, Marcelo F. Ciappina, Tom Kirchner, Michael Schulz

Physics Faculty Research & Creative Works

We apply the frozen-correlation approximation (FCA) to analyze double ionization of helium by energetic highly charged ions. In this model the double ionization amplitude is represented in terms of single ionization amplitudes, which we evaluate within the continuum distorted wave-eikonal initial state (CDW-EIS) approach. Correlation effects are incorporated in the initial and final states, but are neglected during the time the collision process takes place. We implement the FCA using the Monte Carlo event generator technique, which allows us to generate theoretical event files and to compare theory and experiment using the same analysis tools. The comparison with previous theoretical …


Measurement Of The Isolated Prompt Photon Production Cross Section In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain Feb 2011

Measurement Of The Isolated Prompt Photon Production Cross Section In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain

Aerospace, Physics, and Space Science Faculty Publications

The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E T in pp collisions at ffiffi s p ¼ 7 TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2:9 pb 1. Photons are required to have a pseudorapidity j j < 1:45 and E T > 21 GeV, covering the kinematic region 0:006 < xT < 0:086. The measured cross section is found to be in agreement with nextto-leading-order perturbative QCD calculations.


Does Entropic Gravity Bound The Masses Of The Photon And Graviton?, Jonas R. Mureika, R. B. Mann Dec 2010

Does Entropic Gravity Bound The Masses Of The Photon And Graviton?, Jonas R. Mureika, R. B. Mann

Physics Faculty Works

If the information transfer between test particle and holographic screen in entropic gravity respects both the uncertainty principle and causality, a lower limit on the number of bits in the universe relative to its mass may be derived. Furthermore, these limits indicate particles that putatively travel at the speed of light -- the photon and/or graviton -- have a non-zero mass m≥10−68 kg. This result is found to be in excellent agreement with current experimental mass bounds on the graviton and photon, suggesting that entropic gravity may be the result of a (recent) softly-broken local symmetry. Stronger bounds emerge …


Reaction Dynamics In Double Ionization Of Helium By Electron Impact, Marcelo F. Ciappina, Michael Schulz, Tom Kirchner Dec 2010

Reaction Dynamics In Double Ionization Of Helium By Electron Impact, Marcelo F. Ciappina, Michael Schulz, Tom Kirchner

Physics Faculty Research & Creative Works

We present theoretical fully differential cross sections (FDCS) for double ionization of helium by 500 eV and 2 keV electron impact. Contributions from various reaction mechanisms to the FDCS were calculated separately and compared to experimental data. Our theoretical methods are based on the first Born approximation. Higher-order effects are incorporated using the Monte Carlo event generator technique. Earlier, we successfully applied this approach to double ionization by ion impact, and in the work reported here it is extended to electron impact. We demonstrate that at 500 eV impact energy, double ionization is dominated by higher-order mechanisms. Even at 2 …


Triple-Differential Cross Sections For Target Ionization With Simultaneous Projectile Detachment In 200-Kev H⁻ + He Collisions, T. Ferger, Michael Schulz, Daniel Fischer, B. Najjari, R. Moshammer, J. D. Ullrich Oct 2007

Triple-Differential Cross Sections For Target Ionization With Simultaneous Projectile Detachment In 200-Kev H⁻ + He Collisions, T. Ferger, Michael Schulz, Daniel Fischer, B. Najjari, R. Moshammer, J. D. Ullrich

Physics Faculty Research & Creative Works

We have performed a kinematically complete experiment for target ionization with simultaneous projectile detachment (TIPD) in 200-keV H + He collisions. From the data we extracted triple-differential cross sections (TDCSs) for each electron separately. These TDCSs closely resemble corresponding data for single ionization by charged-particle impact. Surprisingly, the contributions from higher-order processes to TIPD, proceeding through two independent interactions of each electron with the core of the respective other collision partner, are found to be somewhat larger than the first-order process proceeding through the electron-electron interaction.


Casimir Forces And Non-Newtonian Gravitation, Roberto Onofrio Oct 2006

Casimir Forces And Non-Newtonian Gravitation, Roberto Onofrio

Dartmouth Scholarship

The search for non-relativistic deviations from Newtonian gravitation can lead to new phenomena signalling the unification of gravity with the other fundamental interactions. Various recent theoretical frameworks indicate a possible window for non-Newtonian forces with gravitational coupling strength in the micrometre range. The major expected background in the same range is attributable to the Casimir force or variants of it if dielectric materials, rather than conducting ones, are considered. Here we review the measurements of the Casimir force performed so far in the micrometre range and how they determine constraints on non-Newtonian gravitation, also discussing the dominant sources of false …


Mutual Ionization In 200-Kev H⁻+ He Collisions, T. Ferger, Daniel Fischer, Michael Schulz, R. Moshammer, A. B. Voitkiv, B. Najjari, J. Ullrich Dec 2005

Mutual Ionization In 200-Kev H⁻+ He Collisions, T. Ferger, Daniel Fischer, Michael Schulz, R. Moshammer, A. B. Voitkiv, B. Najjari, J. Ullrich

Physics Faculty Research & Creative Works

We studied mutual ionization in 200-keV H-+He collisions in a kinematically complete experiment by measuring the fully momentum-analyzed recoil ions and both active electrons in coincidence. Comparison of the data to our calculations, based on various theoretical models, show that mutual ionization proceeds predominantly through the interaction between both electrons. The post-collision interaction between the outgoing ejected electrons as well as higher order processes involving the interaction between the core of both collision partners are also important.


Role Of The Ground State In Electron-Atom Double Ionization, Stephenie J. Jones, Don H. Madison Aug 2003

Role Of The Ground State In Electron-Atom Double Ionization, Stephenie J. Jones, Don H. Madison

Physics Faculty Research & Creative Works

Recently, absolute measurements have been reported for double ionization of helium by 5.6 keV electron-impact. At this high energy, one would think that the first Born approximation for the interaction of the projectile with the atom would be valid. However, on the basis of a lowest-order implementation of a Faddeev-type approach, Berakdar concluded that the approximation was not valid. Here we argue that (i) it is valid at this energy and (ii) the previous discrepancy between calculations in the first Born approximation and the overall magnitude of the measurements was due to a poor description of the ground state.


Black Hole Attractor Varieties And Complex Multiplication, Monika Lynker, Vipul Periwal, Rolf Schimmrigk Jun 2003

Black Hole Attractor Varieties And Complex Multiplication, Monika Lynker, Vipul Periwal, Rolf Schimmrigk

Faculty and Research Publications

Black holes in string theory compactified on Calabi-Yau varieties a priori might be expected to have moduli dependent features. For example the entropy of the black hole might be expected to depend on the complex structure of the manifold. This would be inconsistent with known properties of black holes. Supersymmetric black holes appear to evade this inconsistency by having moduli fields that flow to fixed points in the moduli space that depend only on the charges of the black hole. Moore observed in the case of compactifications with elliptic curve factors that these fixed points are arithmetic, corresponding to curves …


Affinity For Scalar Fields To Dissipate, Arjun Berera, Rudnei O. Ramos Apr 2001

Affinity For Scalar Fields To Dissipate, Arjun Berera, Rudnei O. Ramos

Dartmouth Scholarship

The zero-temperature effective equation of motion is derived for a scalar field interacting with other fields. For a broad range of cases, involving interaction with as few as one or two fields, dissipative regimes are found for the scalar field system. The zero-temperature limit constitutes a baseline effect that will be prevalent in any general statistical state. Thus, the results found here provide strong evidence that dissipation is the norm not the exception for an interacting scalar field system. For application to inflationary cosmology, this provides convincing evidence that warm inflation could be a natural dynamics once proper treatment of …


Fully Differential Cusp Electron Production Cross Sections For 75-Kev H₂⁺ + He Collisions, L. An, Kh Khayvat, Michael Schulz Feb 2001

Fully Differential Cusp Electron Production Cross Sections For 75-Kev H₂⁺ + He Collisions, L. An, Kh Khayvat, Michael Schulz

Physics Faculty Research & Creative Works

A kinematically complete experiment on single ionization for 75-keV H2+ + H e collisions was performed by measuring the fully momentum analyzed projectiles and recoil ions in coincidence. The electron momentum was deduced from momentum conservation. Clear signatures of the postcollision interaction between the outgoing projectiles and the electrons were observed in the momentum spectra of all collision products simultaneously.


Inhomogeneous Nucleation In A Quark-Hadron Pphase Transition, P. Shukla, A. K. Mohanty, S. K. Gupta, Marcelo Gleiser Oct 2000

Inhomogeneous Nucleation In A Quark-Hadron Pphase Transition, P. Shukla, A. K. Mohanty, S. K. Gupta, Marcelo Gleiser

Dartmouth Scholarship

The effect of subcritical hadron bubbles on a first-order quark-hadron phase transition is studied. These subcritical hadron bubbles are created due to thermal fluctuations, and can introduce a finite amount of phase mixing (quark phase mixed with hadron phase) even at and above the critical temperature. For reasonable choices of surface tension and correlation length, as obtained from the lattice QCD calculations, we show that the amount of phase mixing at the critical temperature remains below the percolation threshold. Thus, as the system cools below the critical temperature, the transition proceeds through the nucleation of critical-size hadron bubbles from a …