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ToMCCA-3: A realistic 3-body coalescence model
Authors:
Maximilian Mahlein,
Bhawani Singh,
Michele Viviani,
Francesca Bellini,
Laura Fabbietti,
Alejandro Kievsky,
Laura Elisa Marcucci
Abstract:
The formation of light nuclei in high-energy collisions provides valuable insights into the underlying dynamics of the strong interaction and the structure of the particle-emitting source. Understanding this process is crucial not only for nuclear physics but also for astrophysical studies, where the production of rare antinuclei could serve as a probe for new physics. This work presents a three-b…
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The formation of light nuclei in high-energy collisions provides valuable insights into the underlying dynamics of the strong interaction and the structure of the particle-emitting source. Understanding this process is crucial not only for nuclear physics but also for astrophysical studies, where the production of rare antinuclei could serve as a probe for new physics. This work presents a three-body coalescence model based on the Wigner function formalism, offering a refined description of light-nucleus production. By incorporating realistic two- and three-body nuclear interaction potentials constrained by modern scattering and femtoscopic correlation data, our approach improves on traditional coalescence models. The framework is validated using event generators applied to proton-proton collisions at $\sqrt{s}=13$ TeV to predict the momentum spectra of light (anti) nuclear nuclei with mass number $A=3$, which are then compared with the experimental data from ALICE. Our results demonstrate the sensitivity of light nucleus yields to the choice of nuclear wave functions, emphasizing the importance of an accurate description of the coalescence process. This model lays the foundation for the extension of coalescence studies of $A=3$ light nuclei to a wider range of collision systems and energies.
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Submitted 3 April, 2025;
originally announced April 2025.
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Fundamental Symmetries, Neutrons, and Neutrinos (FSNN): Whitepaper for the 2023 NSAC Long Range Plan
Authors:
B. Acharya,
C. Adams,
A. A. Aleksandrova,
K. Alfonso,
P. An,
S. Baeßler,
A. B. Balantekin,
P. S. Barbeau,
F. Bellini,
V. Bellini,
R. S. Beminiwattha,
J. C. Bernauer,
T. Bhattacharya,
M. Bishof,
A. E. Bolotnikov,
P. A. Breur,
M. Brodeur,
J. P. Brodsky,
L. J. Broussard,
T. Brunner,
D. P. Burdette,
J. Caylor,
M. Chiu,
V. Cirigliano,
J. A. Clark
, et al. (154 additional authors not shown)
Abstract:
This whitepaper presents the research priorities decided on by attendees of the 2022 Town Meeting for Fundamental Symmetries, Neutrons and Neutrinos, which took place December 13-15, 2022 in Chapel Hill, NC, as part of the Nuclear Science Advisory Committee (NSAC) 2023 Long Range Planning process. A total of 275 scientists registered for the meeting. The whitepaper makes a number of explicit recom…
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This whitepaper presents the research priorities decided on by attendees of the 2022 Town Meeting for Fundamental Symmetries, Neutrons and Neutrinos, which took place December 13-15, 2022 in Chapel Hill, NC, as part of the Nuclear Science Advisory Committee (NSAC) 2023 Long Range Planning process. A total of 275 scientists registered for the meeting. The whitepaper makes a number of explicit recommendations and justifies them in detail.
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Submitted 6 April, 2023;
originally announced April 2023.
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Neutrinoless Double Beta Decay
Authors:
C. Adams,
K. Alfonso,
C. Andreoiu,
E. Angelico,
I. J. Arnquist,
J. A. A. Asaadi,
F. T. Avignone,
S. N. Axani,
A. S. Barabash,
P. S. Barbeau,
L. Baudis,
F. Bellini,
M. Beretta,
T. Bhatta,
V. Biancacci,
M. Biassoni,
E. Bossio,
P. A. Breur,
J. P. Brodsky,
C. Brofferio,
E. Brown,
R. Brugnera,
T. Brunner,
N. Burlac,
E. Caden
, et al. (207 additional authors not shown)
Abstract:
This White Paper, prepared for the Fundamental Symmetries, Neutrons, and Neutrinos Town Meeting related to the 2023 Nuclear Physics Long Range Plan, makes the case for double beta decay as a critical component of the future nuclear physics program. The major experimental collaborations and many theorists have endorsed this white paper.
This White Paper, prepared for the Fundamental Symmetries, Neutrons, and Neutrinos Town Meeting related to the 2023 Nuclear Physics Long Range Plan, makes the case for double beta decay as a critical component of the future nuclear physics program. The major experimental collaborations and many theorists have endorsed this white paper.
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Submitted 21 December, 2022;
originally announced December 2022.
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On coalescence as the origin of nuclei in hadronic collisions
Authors:
Francesca Bellini,
Kfir Blum,
Alexander Phillip Kalweit,
Maximiliano Puccio
Abstract:
The origin of weakly-bound nuclear clusters in hadronic collisions is a key question to be addressed by heavy-ion collision (HIC) experiments. The measured yields of clusters are approximately consistent with expectations from phenomenological statistical hadronisation models (SHMs), but a theoretical understanding of the dynamics of cluster formation prior to kinetic freeze out is lacking. The co…
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The origin of weakly-bound nuclear clusters in hadronic collisions is a key question to be addressed by heavy-ion collision (HIC) experiments. The measured yields of clusters are approximately consistent with expectations from phenomenological statistical hadronisation models (SHMs), but a theoretical understanding of the dynamics of cluster formation prior to kinetic freeze out is lacking. The competing model is nuclear coalescence, which attributes cluster formation to the effect of final state interactions (FSI) during the propagation of the nuclei from kinetic freeze out to the observer. This phenomenon is closely related to the effect of FSI in imprinting femtoscopic correlations between continuum pairs of particles at small relative momentum difference. We give a concise theoretical derivation of the coalescence--correlation relation, predicting nuclear cluster spectra from femtoscopic measurements. We review the fact that coalescence derives from a relativistic Bethe-Salpeter equation, and recall how effective quantum mechanics controls the dynamics of cluster particles that are nonrelativistic in the cluster centre of mass frame. We demonstrate that the coalescence--correlation relation is roughly consistent with the observed cluster spectra in systems ranging from PbPb to pPb and pp collisions. Paying special attention to nuclear wave functions, we derive the coalescence prediction for hypertriton and show that it, too, is roughly consistent with the data. Our work motivates a combined experimental programme addressing femtoscopy and cluster production under a unified framework. Upcoming pp, pPb and peripheral PbPb data analysed within such a programme could stringently test coalescence as the origin of clusters.
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Submitted 3 July, 2020;
originally announced July 2020.
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A next-generation LHC heavy-ion experiment
Authors:
D. Adamová,
G. Aglieri Rinella,
M. Agnello,
Z. Ahammed,
D. Aleksandrov,
A. Alici,
A. Alkin,
T. Alt,
I. Altsybeev,
D. Andreou,
A. Andronic,
F. Antinori,
P. Antonioli,
H. Appelshäuser,
R. Arnaldi,
I. C. Arsene,
M. Arslandok,
R. Averbeck,
M. D. Azmi,
X. Bai,
R. Bailhache,
R. Bala,
L. Barioglio,
G. G. Barnaföldi,
L. S. Barnby
, et al. (374 additional authors not shown)
Abstract:
The present document discusses plans for a compact, next-generation multi-purpose detector at the LHC as a follow-up to the present ALICE experiment. The aim is to build a nearly massless barrel detector consisting of truly cylindrical layers based on curved wafer-scale ultra-thin silicon sensors with MAPS technology, featuring an unprecedented low material budget of 0.05% X$_0$ per layer, with th…
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The present document discusses plans for a compact, next-generation multi-purpose detector at the LHC as a follow-up to the present ALICE experiment. The aim is to build a nearly massless barrel detector consisting of truly cylindrical layers based on curved wafer-scale ultra-thin silicon sensors with MAPS technology, featuring an unprecedented low material budget of 0.05% X$_0$ per layer, with the innermost layers possibly positioned inside the beam pipe. In addition to superior tracking and vertexing capabilities over a wide momentum range down to a few tens of MeV/$c$, the detector will provide particle identification via time-of-flight determination with about 20~ps resolution. In addition, electron and photon identification will be performed in a separate shower detector. The proposed detector is conceived for studies of pp, pA and AA collisions at luminosities a factor of 20 to 50 times higher than possible with the upgraded ALICE detector, enabling a rich physics program ranging from measurements with electromagnetic probes at ultra-low transverse momenta to precision physics in the charm and beauty sector.
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Submitted 2 May, 2019; v1 submitted 31 January, 2019;
originally announced February 2019.
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Future physics opportunities for high-density QCD at the LHC with heavy-ion and proton beams
Authors:
Z. Citron,
A. Dainese,
J. F. Grosse-Oetringhaus,
J. M. Jowett,
Y. -J. Lee,
U. A. Wiedemann,
M. Winn,
A. Andronic,
F. Bellini,
E. Bruna,
E. Chapon,
H. Dembinski,
D. d'Enterria,
I. Grabowska-Bold,
G. M. Innocenti,
C. Loizides,
S. Mohapatra,
C. A. Salgado,
M. Verweij,
M. Weber,
J. Aichelin,
A. Angerami,
L. Apolinario,
F. Arleo,
N. Armesto
, et al. (160 additional authors not shown)
Abstract:
The future opportunities for high-density QCD studies with ion and proton beams at the LHC are presented. Four major scientific goals are identified: the characterisation of the macroscopic long wavelength Quark-Gluon Plasma (QGP) properties with unprecedented precision, the investigation of the microscopic parton dynamics underlying QGP properties, the development of a unified picture of particle…
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The future opportunities for high-density QCD studies with ion and proton beams at the LHC are presented. Four major scientific goals are identified: the characterisation of the macroscopic long wavelength Quark-Gluon Plasma (QGP) properties with unprecedented precision, the investigation of the microscopic parton dynamics underlying QGP properties, the development of a unified picture of particle production and QCD dynamics from small (pp) to large (nucleus--nucleus) systems, the exploration of parton densities in nuclei in a broad ($x$, $Q^2$) kinematic range and the search for the possible onset of parton saturation. In order to address these scientific goals, high-luminosity Pb-Pb and p-Pb programmes are considered as priorities for Runs 3 and 4, complemented by high-multiplicity studies in pp collisions and a short run with oxygen ions. High-luminosity runs with intermediate-mass nuclei, for example Ar or Kr, are considered as an appealing case for extending the heavy-ion programme at the LHC beyond Run 4. The potential of the High-Energy LHC to probe QCD matter with newly-available observables, at twice larger center-of-mass energies than the LHC, is investigated.
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Submitted 25 February, 2019; v1 submitted 17 December, 2018;
originally announced December 2018.
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Testing coalescence and statistical-thermal production scenarios for (anti-)(hyper-)nuclei and exotic QCD objects at energies available at the CERN Large Hadron Collider
Authors:
Francesca Bellini,
Alexander Philipp Kalweit
Abstract:
We present a detailed comparison of coalescence and thermal-statistical models for the production of (anti-)(hyper-)nuclei in high-energy collisions. For the first time, such a study is carried out as a function of the size of the object relative to the size of the particle emitting source. Our study reveals large differences between the two scenarios for the production of objects with extended wa…
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We present a detailed comparison of coalescence and thermal-statistical models for the production of (anti-)(hyper-)nuclei in high-energy collisions. For the first time, such a study is carried out as a function of the size of the object relative to the size of the particle emitting source. Our study reveals large differences between the two scenarios for the production of objects with extended wave-functions. While both models give similar predictions and show similar agreement with experimental data for (anti-)deuterons and (anti-)3He nuclei, they largely differ in their description of (anti-)hyper-triton production. We propose to address experimentally the comparison of the production models by measuring the coalescence parameter systematically for different (anti-)(hyper-)nuclei in different collision systems and differentially in multiplicity. Such measurements are feasible with the current and upgraded Large Hadron Collider experiments. Our findings highlight the unique potential of ultra-relativistic heavy-ion collisions as a laboratory to clarify the internal structure of exotic QCD objects and can serve as a basis for more refined calculations in the future.
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Submitted 4 June, 2019; v1 submitted 16 July, 2018;
originally announced July 2018.
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INFN What Next: Ultra-relativistic Heavy-Ion Collisions
Authors:
A. Dainese,
E. Scomparin,
G. Usai,
P. Antonioli,
R. Arnaldi,
A. Beraudo,
E. Bruna,
G. E. Bruno,
S. Bufalino,
P. Di Nezza,
M. P. Lombardo,
R. Nania,
F. Noferini,
C. Oppedisano,
S. Piano,
F. Prino,
A. Rossi,
M. Agnello,
W. M. Alberico,
B. Alessandro,
A. Alici,
G. Andronico,
F. Antinori,
S. Arcelli,
A. Badala
, et al. (116 additional authors not shown)
Abstract:
This document was prepared by the community that is active in Italy, within INFN (Istituto Nazionale di Fisica Nucleare), in the field of ultra-relativistic heavy-ion collisions. The experimental study of the phase diagram of strongly-interacting matter and of the Quark-Gluon Plasma (QGP) deconfined state will proceed, in the next 10-15 years, along two directions: the high-energy regime at RHIC a…
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This document was prepared by the community that is active in Italy, within INFN (Istituto Nazionale di Fisica Nucleare), in the field of ultra-relativistic heavy-ion collisions. The experimental study of the phase diagram of strongly-interacting matter and of the Quark-Gluon Plasma (QGP) deconfined state will proceed, in the next 10-15 years, along two directions: the high-energy regime at RHIC and at the LHC, and the low-energy regime at FAIR, NICA, SPS and RHIC. The Italian community is strongly involved in the present and future programme of the ALICE experiment, the upgrade of which will open, in the 2020s, a new phase of high-precision characterisation of the QGP properties at the LHC. As a complement of this main activity, there is a growing interest in a possible future experiment at the SPS, which would target the search for the onset of deconfinement using dimuon measurements. On a longer timescale, the community looks with interest at the ongoing studies and discussions on a possible fixed-target programme using the LHC ion beams and on the Future Circular Collider.
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Submitted 12 February, 2016;
originally announced February 2016.
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Discovery of the $^{151}$Eu $α$ decay
Authors:
N. Casali,
S. S. Nagorny,
F. Orio,
L. Pattavina,
J. W. Beeman,
F. Bellini,
L. Cardani,
I. Dafinei,
S. Di Domizio,
M. L. Di Vacri,
L. Gironi,
M. B. Kosmyna,
B. P. Nazarenko,
S. Nisi,
G. Pessina,
G. Piperno,
S. Pirro,
C. Rusconi,
A. N. Shekhovtsov,
C. Tomei,
M. Vignati
Abstract:
We report on the first compelling observation of $α$ decay of $^{151}$Eu to the ground state of $^{147}$Pm. The measurement was performed using a 6.15 g Li$_6$Eu(BO$_3$)$_3$ crystal operated as a scintillating bolometer. The Q-value and half-life measured are: Q = 1948.9$\pm 6.9(stat.) \pm 5.1(syst.)$ keV, and T$_{1/2}=\left( 4.62\pm0.95(stat.)\pm0.68(syst.)\right) \times 10^{18}$ y . The half-lif…
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We report on the first compelling observation of $α$ decay of $^{151}$Eu to the ground state of $^{147}$Pm. The measurement was performed using a 6.15 g Li$_6$Eu(BO$_3$)$_3$ crystal operated as a scintillating bolometer. The Q-value and half-life measured are: Q = 1948.9$\pm 6.9(stat.) \pm 5.1(syst.)$ keV, and T$_{1/2}=\left( 4.62\pm0.95(stat.)\pm0.68(syst.)\right) \times 10^{18}$ y . The half-life prediction of nuclear theory using the Coulomb and proximity potential model are in good agreement with this experimental result.
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Submitted 12 March, 2014; v1 submitted 12 November, 2013;
originally announced November 2013.