We examined the transverse momentum (  $ p_T $  ) spectra of various identified particles, encompassing both light-flavored and strange hadrons (  $ p_T $  ,   $ p_T $  ,   $ p_T $  , ϕ,   $ p_T $  ,   $ p_T $  ,   $ p_T $  , and   $ p_T $  ), across different multiplicity classes in proton-proton collisions (p-p) at a center-of-mass energy of   $ p_T $   TeV. Utilizing the Tsallis and Hagedorn models, parameters relevant to the bulk properties of nuclear matter were extracted. Both models exhibit good agreement with experimental data. In our analyses, we observed a consistent decrease in the effective temperature (T) for the Tsallis model and the kinetic or thermal freeze-out temperature (  $ p_T $  ) for the Hagedorn model, as we transitioned from higher multiplicity (class-I) to lower multiplicity (class-X). This trend is attributed to the diminished energy transfer in higher multiplicity classes. Additionally, we observed that the transverse flow velocity (  $ p_T $  ) experiences a decline from class-I to class-X. The normalization constant, which represents the multiplicity of produced particles, was observed to decrease as we moved toward higher multiplicity classes. While the effective and kinetic freeze-out temperatures, as well as the transverse flow velocity, show a mild dependency on multiplicity for lighter particles, this dependency becomes more pronounced for heavier particles. The multiplicity parameter for heavier particles was observed to be smaller than that of lighter particles, indicating a greater abundance of lighter hadrons compared to heavier ones. Various particle species were observed to undergo decoupling from the fireball at distinct temperatures: lighter particles exhibit lower temperatures, while heavier ones show higher temperatures, thereby supporting the concept of multiple freeze-out scenarios. Moreover, we identified a positive correlation between the kinetic freeze-out temperature and transverse flow velocity, a scenario where particles experience stronger collective motion at a higher freeze-out temperature. The reason for this positive correlation is that, as the multiplicity increases, more energy is transferred into the system. This increased energy causes greater excitation and pressure within the system, leading to a quick expansion.

Pakistan

Muhammad Ajaz

Majid Shehzad

China

Muhammad Waqas

Saudi Arabia

Haifa I. Alrebdi

United States

Mohammad Ayaz Ahmad

Antalov Jagnandan

Shawn Jagnandan

Murad Badshah

Jalal Hasan Baker

Abdul Mosawir Quraishi

Multiplicity dependence of the freezeout parameters in high energy hadron-hadron collisions  

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the   $ p\to \bar{\nu} K^+ $   mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via   $ p\to \bar{\nu} K^+ $   is 36.9% ± 4.9% with a background level of   $ p\to \bar{\nu} K^+ $     $ p\to \bar{\nu} K^+ $   events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is   $ p\to \bar{\nu} K^+ $   years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies.

Chile

Angel Abusleme

France

Thomas Adam

Shakeel Ahmad

Rizwan Ahmed

Italy

Sebastiano Aiello

Muhammad Akram

Fengpeng An

Qi An

Giuseppe Andronico

JINR

Nikolay Anfimov

Vito Antonelli

Tatiana Antoshkina

Thailand

Burin Asavapibhop

João Pedro Athayde Marcondes de André

Didier Auguste

Nikita Balashov

Wander Baldini

Andrea Barresi

Davide Basilico

Eric Baussan

Marco Bellato

Antonio Bergnoli

Germany

Thilo Birkenfeld

Sylvie Blin

David Blum

Simon Blyth

Anastasia Bolshakova

Mathieu Bongrand

Clément Bordereau

Dominique Breton

Augusto Brigatti

Riccardo Brugnera

Riccardo Bruno

Antonio Budano

Mario Buscemi

Jose Busto

Ilya Butorov

Anatael Cabrera

Barbara Caccianiga

Hao Cai

Xiao Cai

Yanke Cai

Zhiyan Cai

Riccardo Callegari

Antonio Cammi

Agustin Campeny

Chuanya Cao

Guofu Cao

Jun Cao

Rossella Caruso

Cédric Cerna

Jinfan Chang

Taiwan

Yun Chang

Pingping Chen

Po-An Chen

Shaomin Chen

Xurong Chen

Yi-Wen Chen

Yixue Chen

Yu Chen

Zhang Chen

Jie Cheng

Yaping Cheng

Alexey Chetverikov

Davide Chiesa

Brazil

Pietro Chimenti

Artem Chukanov

Gérard Claverie

Catia Clementi

Belgium

Barbara Clerbaux

Selma Conforti Di Lorenzo

Daniele Corti

Flavio Dal Corso

Olivia Dalager

Christophe De La Taille

Zhi Deng

Ziyan Deng

Wilfried Depnering

Marco Diaz

Xuefeng Ding

Yayun Ding

Bayu Dirgantara

Sergey Dmitrievsky

Czechia

Tadeas Dohnal

Dmitry Dolzhikov

Russia

Georgy Donchenko

Jianmeng Dong

Evgeny Doroshkevich

Marcos Dracos

Frédéric Druillole

Ran Du

Shuxian Du

Stefano Dusini

Martin Dvorak

Finland

Timo Enqvist

Heike Enzmann

Andrea Fabbri

Ulrike Fahrendholz

Donghua Fan

Lei Fan

JUNO sensitivity on proton decay →   Searches  

We study damping signatures at the Jiangmen Underground Neutrino Observatory (JUNO), a medium-baseline reactor neutrino oscillation experiment. These damping signatures are motivated by various new physics models, including quantum decoherence, ν 3 decay, neutrino absorption, and wave packet decoherence. The phenomenological effects of these models can be characterized by exponential damping factors at the probability level. We assess how well JUNO can constrain these damping parameters and how to disentangle these different damping signatures at JUNO. Compared to current experimental limits, JUNO can significantly improve the limits on τ 3/m 3 in the ν 3 decay model, the width of the neutrino wave packet σ  x , and the intrinsic relative dispersion of neutrino momentum σ rel.

Jun Wang

Jiajun Liao

Wei Wang

João Athayde Marcondes de André

Slovakia

Andrej Babic

Flavio Corso

Christophe Taille

Jiawei Deng

Damping signatures at JUNO, a medium-baseline reactor neutrino oscillation experiment

JUNO is a massive liquid scintillator detector with a primary scientific goal of determining the neutrino mass ordering by studying the oscillated anti-neutrino flux coming from two nuclear power plants at 53 km distance. The expected signal anti-neutrino interaction rate is only 60 counts per day (cpd), therefore a careful control of the background sources due to radioactivity is critical. In particular, natural radioactivity present in all materials and in the environment represents a serious issue that could impair the sensitivity of the experiment if appropriate countermeasures were not foreseen. In this paper we discuss the background reduction strategies undertaken by the JUNO collaboration to reduce at minimum the impact of natural radioactivity. We describe our efforts for an optimized experimental design, a careful material screening and accurate detector production handling, and a constant control of the expected results through a meticulous Monte Carlo simulation program. We show that all these actions should allow us to keep the background count rate safely below the target value of 10 Hz (i.e. ∼1 cpd accidental background) in the default fiducial volume, above an energy threshold of 0.7 MeV.

João André

Oliviero Cremonesi

Lukas Fajt

Jian Fang

Radioactivity control strategy for the JUNO detector

The OSIRIS detector is a subsystem of the liquid scintillator filling chain of the JUNO reactor neutrino experiment. Its purpose is to validate the radiopurity of the scintillator to assure that all components of the JUNO scintillator system work to specifications and only neutrino-grade scintillator is filled into the JUNO Central Detector. The aspired sensitivity level of  $$10^{-16}\hbox { g/g}$$  <math> <mrow> <msup> <mn>10</mn> <mrow> <mo>-</mo> <mn>16</mn> </mrow> </msup> <mspace width="0.333333em"></mspace> <mtext>g/g</mtext> </mrow> </math>   of  $$^{238}\hbox {U}$$  <math> <mrow> <msup> <mrow></mrow> <mn>238</mn> </msup> <mtext>U</mtext> </mrow> </math>   and  $$^{232}\hbox {Th}$$  <math> <mrow> <msup> <mrow></mrow> <mn>232</mn> </msup> <mtext>Th</mtext> </mrow> </math>   requires a large ( $$\sim 20\,\hbox {m}^3$$  <math> <mrow> <mo>∼</mo> <mn>20</mn> <mspace width="0.166667em"></mspace> <msup> <mtext>m</mtext> <mn>3</mn> </msup> </mrow> </math>  ) detection volume and ultralow background levels. The present paper reports on the design and major components of the OSIRIS detector, the detector simulation as well as the measuring strategies foreseen and the sensitivity levels to U/Th that can be reached in this setup.

Guangpeng An

Selma Lorenzo

Salvatore Costa

The design and sensitivity of JUNO’s scintillator radiopurity pre-detector OSIRIS

Atmospheric neutrinos are one of the most relevant natural neutrino sources that can be exploited to infer properties about cosmic rays and neutrino oscillations. The Jiangmen Underground Neutrino Observatory (JUNO) experiment, a 20 kton liquid scintillator detector with excellent energy resolution is currently under construction in China. JUNO will be able to detect several atmospheric neutrinos per day given the large volume. A study on the JUNO detection and reconstruction capabilities of atmospheric  $$\nu _e$$  <math> <msub> <mi>ν</mi> <mi>e</mi> </msub> </math>   and  $$\nu _\mu $$  <math> <msub> <mi>ν</mi> <mi>μ</mi> </msub> </math>   fluxes is presented in this paper. In this study, a sample of atmospheric neutrino Monte Carlo events has been generated, starting from theoretical models, and then processed by the detector simulation. The excellent timing resolution of the 3” PMT light detection system of JUNO detector and the much higher light yield for scintillation over Cherenkov allow to measure the time structure of the scintillation light with very high precision. Since  $$\nu _e$$  <math> <msub> <mi>ν</mi> <mi>e</mi> </msub> </math>   and  $$\nu _\mu $$  <math> <msub> <mi>ν</mi> <mi>μ</mi> </msub> </math>   interactions produce a slightly different light pattern, the different time evolution of light allows to discriminate the flavor of primary neutrinos. A probabilistic unfolding method has been used, in order to infer the primary neutrino energy spectrum from the detector experimental observables. The simulated spectrum has been reconstructed between 100 MeV and 10 GeV, showing a great potential of the detector in the atmospheric low energy region.

Enrico Bernieri

JUNO sensitivity to low energy atmospheric neutrino spectra

Transverse momentum (mass) spectra of positively and negatively charged pions and of positively and negatively charged kaons, protons, and antiprotons produced at mid-(pseudo)rapidity in various collisions at high energies are analyzed in this work. The experimental data measured in central gold-gold, central lead-lead, and inelastic proton-proton collisions by several international collaborations are studied. The (two-component) standard distribution is used to fit the data and extract the excitation function of effective temperature. Then, the excitation functions of kinetic freeze-out temperature, transverse flow velocity, and initial temperature are obtained. In the considered collisions, the four parameters increase with the increase of collision energy in general, and the kinetic freeze-out temperature appears at the trend of saturation at the top Relativistic Heavy Ion Collider and the Large Hadron Collider.

Fu-Hu Liu

Li-Li Li

Yemen

Rasha Al-Yusufi

Altaf Mujear

Excitation Functions of Related Parameters from Transverse Momentum (Mass) Spectra in High-Energy Collisions

Centrality-dependent double-differential transverse momentum spectra of negatively charged particles (π−, K−, and <math id="M1"><mover><mi>p</mi><mo>¯</mo></mover></math>) at the mid(pseudo)rapidity interval in nuclear collisions are analyzed by the standard distribution in terms of multicomponent. The experimental data measured in gold-gold (Au-Au) collisions by the PHENIX Collaboration at the Relativistic Heavy Ion Collider (RHIC) and in lead-lead (Pb-Pb) collisions by the ALICE Collaboration at the Large Hadron Collider (LHC) are studied. The effective temperature, initial temperature, kinetic freeze-out temperature, transverse flow velocity, and kinetic freeze-out volume are extracted from the fitting to transverse momentum spectra. We observed that the mentioned five quantities increase with the increase of event centrality due to the fact that the average transverse momentum increases with the increase of event centrality. This renders that larger momentum (energy) transfer and further multiple scattering had happened in central centrality.

Zafar Wazir

Dependence of Temperatures and Kinetic Freeze-Out Volume on Centrality in Au-Au and Pb-Pb Collisions at High Energy

By using the method of data-driven reanalysis, the midrapidity transverse momentum <math id="M1"><mfenced><mrow><msub><mrow><mi>p</mi></mrow><mrow><mtext>T</mtext></mrow></msub></mrow></mfenced></math> spectra of charged hadrons (<math id="M2"><msup><mrow><mi>π</mi></mrow><mrow><mo>+</mo></mrow></msup></math>, <math id="M3"><msup><mrow><mi>K</mi></mrow><mrow><mo>+</mo></mrow></msup></math>, and <math id="M4"><mi>p</mi></math>) produced in central and peripheral gold-gold (Au-Au) collisions from the Beam Energy Scan (BES) program at the Relativistic Heavy Ion Collider (RHIC) are fitted by using the blast-wave model with the Boltzmann-Gibbs statistics. The model results are in agreement with the experimental data measured by the STAR Collaboration at the RHIC-BES energies. We observe that the kinetic freeze-out temperature <math id="M5"><mfenced><mrow><msub><mrow><mi>T</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow></mfenced></math>, transverse flow velocity <math id="M6"><mfenced><mrow><msub><mrow><mi>β</mi></mrow><mrow><mtext>T</mtext></mrow></msub></mrow></mfenced></math>, mean transverse momentum <math id="M7"><mfenced><mrow><mfenced><mrow><msub><mrow><mi>p</mi></mrow><mrow><mtext>T</mtext></mrow></msub></mrow></mfenced></mrow></mfenced></math>, and initial temperature <math id="M8"><mfenced><mrow><msub><mrow><mi>T</mi></mrow><mrow><mtext>i</mtext></mrow></msub></mrow></mfenced></math> increase with collision energy as well as with event centrality.

Bao-Chun Li

Kinetic Freeze-Out Temperature and Transverse Flow Velocity in Au-Au Collisions at RHIC-BES Energies

A dedicated search is presented for new phenomena in inclusive 8- and 10-jet final states with low missing transverse momentum, with and without identification of jets originating from b quarks. The analysis is based on data from proton–proton collisions corresponding to an integrated luminosity of 19.7fb−1 collected with the CMS detector at the LHC at s=8TeV . The dominant multijet background expectations are obtained from low jet multiplicity control samples. Data agree well with the standard model background predictions, and limits are set in several benchmark models. Colorons (axigluons) with masses between 0.6 and 0.75 (up to 1.15) TeV are excluded at 95% confidence level. Similar exclusion limits for gluinos in R -parity violating supersymmetric scenarios are from 0.6 up to 1.1 TeV. These results comprise the first experimental probe of the coloron and axigluon models in multijet final states.

Armenia

Vardan Khachatryan

Albert M Sirunyan

Armen Tumasyan

Austria

Wolfgang Adam

Ece Aşılar

Thomas Bergauer

Johannes Brandstetter

Erica Brondolin

Marko Dragicevic

Janos Erö

Martin Flechl

Markus Friedl

Rudolf Fruehwirth

Vasile Mihai Ghete

Christian Hartl

Natascha Hörmann

Josef Hrubec

Manfred Jeitler

Axel König

Ilse Krätschmer

Dietrich Liko

Takashi Matsushita

Ivan Mikulec

Dinyar Rabady

Navid Rad

Babak Rahbaran

Herbert Rohringer

Jochen Schieck

Josef Strauss

Wolfgang Treberer-Treberspurg

Search for new phenomena in events with high jet multiplicity and low missing transverse momentum in proton–proton collisions at s=8TeV