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The first measurement of inclusive J/psi polarization at mid-rapidity (|y^{J/psi}| < 0.8) in 200 GeV Ru+Ru and Zr+Zr collisions at sqrt(s_NN) = 200 GeV with the STAR experiment at RHIC is presented. J/psi mesons are reconstructed through their di-electron (e+e-) decay channel. The polarization parameters (lambda_theta, lambda_phi) are measured as a function of the J/psi transverse momentum (p_T) and collision centrality in both the helicity and the Collins-Soper frames. These polarization parameters are found to be consistent with zero across the measured J/psi p_T range of 0.2 < p_T < 10 GeV/c and across collision centralities within 0-80 percent in both frames. These results are consistent with corresponding measurements p+p collisions at the same collision energy and with transport-model calculations.
The STAR experiment at the Relativistic Heavy Ion Collider presents measurements of correlations between charged hadron triggers of high transverse momenta ($7 < p_{\rm T} < 30$ GeV/$c$) with recoiling charged hadrons ($3 < p_{\rm T} < 7$ GeV/$c$) or charged--particle jets ($p_{\rm T, jet} > 8$ GeV/$c$) in event--activity selected O+O collisions at $\sqrt{s_{\mathrm {NN}}}=200$ GeV. Yields of associated hadrons and jets, normalized by the number of trigger hadrons, are suppressed by approximately 20\% in high event activity relative to low event activity collisions, with an absence of suppression excluded with high significance. This suppression corresponds to a shift in p_{\rm T} of $0.70\pm0.15~(\rm stat.)~\pm0.10~(\rm syst.)$ GeV/$c$ for large--radius charged--particle jets ($R=0.5$), quantifying their energy redistribution due to final--state interactions. These measurements provide strong evidence for jet quenching in O+O collisions at $\sqrt{s_\mathrm{NN}}=200$ GeV, offering new insight into quark--gluon plasma formation in small collision systems.
In this paper, a study of cold nuclear matter (CNM) effects is reported based on the new STAR measurement of inclusive $J/ψ$ production in $p+p$ and $p+\text{Au}$ collisions at $\sqrt{s_\text{NN}}$ = 200 GeV, and a combined $J/ψ\rightarrow e^{+}e^{-}$ cross section in $p+p$ collisions at $\sqrt{s}$ = 200 GeV is provided. Given the long-established presumption that the energy density and the temperature produced in proton-nucleon collisions are insufficient to form QGP droplets, CNM effects in $p+\text{Au}$ collisions are quantified by the nuclear modification factor ($R_{p\text{Au}}$), defined as the ratio of the yield of the inclusive $J/ψ$ in $p+\text{Au}$ collisions to that in $p+p$ collisions, scaled by the average number of binary nucleon-nucleon collisions. The $R_{p\text{Au}}$ is derived as a function of transverse momentum ($p_\text{T}$) in the range 4--12 GeV/$c$ and is averaged within the rapidity ($y$) and azimuthal angle ($\varphi$) coverage of $|y|<1$, $0 \leq \varphi < 2π$. The result is consistent with unity, suggesting negligible modification of the yield by CNM effects in this kinematic region. Various model calculations are in agreement with the $R_{p\text{A
Quantum cryptography is now considered as a promising technology due to its promise of unconditional security. In recent years, rigorous work is being done for the experimental realization of quantum key distribution (QKD) protocols to realize secure networks. Among various QKD protocols, coherent one way and differential phase shift QKD protocols have undergone rapid experimental developments due to the ease of experimental implementations with the present available technology. In this work, we have experimentally realized optical fiber based coherent one way and differential phase shift QKD protocols at telecom wavelength. Both protocols belong to a class of protocols named as distributed phase reference protocol in which weak coherent pulses are used to encode the information. Further, we have analyzed the key rates with respect to different parameters such distance, disclose rate, compression ratio and detector dead time.
We report measurements of $\varUpsilon(1S)$, $\varUpsilon(2S)$ and $\varUpsilon(3S)$ production in $\textit{p+p}$ collisions at $\sqrt{s}=500\:\mathrm{GeV}$ by the STAR experiment in year 2011, corresponding to an integrated luminosity $\mathcal{L}_{int}=13\:\mathrm{pb^{-1}}$. The results provide precise cross sections, transverse momentum ($p_{T}$) and rapidity ($y$) spectra, as well as cross section ratios for $p_{\mathrm{T}}<10\:\mathrm{GeV/c}$ and $|y|<1$. The dependence of the $\varUpsilon$ yield on charged particle multiplicity has also been measured, offering new insights into the mechanisms of quarkonium production. The data are compared to various theoretical models: the Color Evaporation Model (CEM) accurately describes the $\varUpsilon(1S)$ production, while the Color Glass Condensate + Non-relativistic Quantum Chromodynamics (CGC+NRQCD) model overestimates the data, particularly at low $p_{T}$. Conversely, the Color Singlet Model (CSM) underestimates the rapidity dependence. These discrepancies highlight the need for further development in understanding the production dynamics of heavy quarkonia in high-energy hadronic collisions. The trend in the multiplicity dep
This article presents measurements of inclusive $J/ψ$ production at midrapidity ($\left|y\right| <$ 1.0) in Au+Au collisions at $\sqrt{s_\mathrm{NN}} = 54.4$ GeV with the STAR detector at the Relativistic Heavy Ion Collider. A suppression of the $J/ψ$ yield, quantified using the nuclear modification factors ($R_{\mathrm{AA}}$, $R_{\mathrm{CP}}$), is observed with respect to the scaled production in $p$+$p$ collisions. The dependence of $R_{\mathrm{AA}}$ on collision centrality and $J/ψ$ transverse momentum is measured with improved precision compared to previous measurements at 39 and 62.4 GeV, while the centrality dependence of $R_{\mathrm{CP}}$ is measured and compared to the same results at 39, 62.4, and 200 GeV. In central collisions, no significant collision energy dependence of $R_{\mathrm{AA}}$ is found within uncertainties for collision energies between 17.3 and 200 GeV. Two transport model calculations that include dissociation and regeneration contributions are consistent with the experimental results within uncertainties. Although no significant collision energy dependence of the $J/ψ$ suppression in high energy heavy-ion collisions up to $\sqrt{s_\mathrm{NN}} = 200$
In heavy-ion collision experiments, the global collectivity of final-state particles can be quantified by anisotropic flow coefficients ($v_n$). The first-order flow coefficient, also referred to as the directed flow ($v_{1}$), describes the collective sideward motion of produced particles and nuclear fragments in heavy-ion collisions. It carries information on the very early stage of the collision, especially at large pseudorapidity ($η$), where it is believed to be generated during the nuclear passage time. Directed flow therefore probes the onset of bulk collective dynamics during thermalization, providing valuable experimental guidance to models of the pre-equilibrium stage. In 2018, the Event Plane Detector (EPD) was installed in STAR and used for the Beam Energy Scan phase-II (BES-II) data taking. The combination of EPD ($2.1 <|η|< 5.1$) and high-statistics BES-II data enables us to extend the $v_{1}$ measurement to the forward and backward $η$ regions. In this paper, we present the measurement of $v_{1}$ over a wide $η$ range in Au+Au collisions at $\sqrt{s_{NN}}=$ 19.6 and 27 GeV using the STAR EPD. The results of the analysis at $\sqrt{s_{NN}}=$19.6 GeV exhibit excel
Transparency protocols are protocols whose actions can be publicly monitored by observers (such observers may include regulators, rights advocacy groups, or the general public). The observed actions are typically usages of private keys such as decryptions, and signings. Examples of transparency protocols include certificate transparency, cryptocurrency, transparent decryption, and electronic voting. These protocols usually pose a challenge for automatic verification, because they involve sophisticated data types that have strong properties, such as Merkle trees, that allow compact proofs of data presence and tree extension. We address this challenge by introducing new features in ProVerif, and a methodology for using them. With our methodology, it is possible to describe the data type quite abstractly, using ProVerif axioms, and prove the correctness of the protocol using those axioms as assumptions. Then, in separate steps, one can define one or more concrete implementations of the data type, and again use ProVerif to show that the implementations satisfy the assumptions that were coded as axioms. This helps make compositional proofs, splitting the proof burden into several manage
We present two abstractions for designing modular state machine replication (SMR) protocols: trees and turtles. A tree captures the set of possible state machine histories, while a turtle represents a subprotocol that tries to find agreement in this tree. We showcase the applicability of these abstractions by constructing crash-tolerant SMR protocols out of abstract tree turtles and providing examples of tree turtle implementations. Tree turtles can also be extended to be made Byzantine fault-tolerant (BFT). The modularity of tree turtles allows a generic approach for adding a leader for liveness. We expect that these abstractions will simplify reasoning and formal verification of SMR protocols as well as facilitate innovation in protocol designs.
Creativity and strategic foresight have been extensively studied through descriptive theories -- Koestler's bisociation (1964), de Bono's lateral thinking (1967), and Ansoff's weak signals (1975) explain why creative and strategic insights occur, but offer limited guidance on how to produce them on demand. This paper presents two executable protocols that bridge this theory-practice gap: GHOSTY COLLIDER, a 5-step protocol for cross-domain creative emergence through structural de-labeling and collision, and PRECOG PROTOCOL, a 5-step protocol for signal-based strategic foresight with multi-axis timing judgment. We formalize established theories into repeatable, step-by-step procedures with explicit quality criteria, anti-pattern detection, and measurable outputs. We evaluate the protocols through three complementary methods: (1) five detailed case studies across distinct domains, (2) controlled comparisons against standard methods using identical inputs, and (3) a batch experiment across eight random domain pairings (N=8, success rate 87.5%, failure rate 12.5%) with one blind evaluation. Preliminary evidence suggests that protocol-driven outputs exhibit greater structural novelty, hi
We design and analyze new protocols to verify the correctness of various computations on matrices over the ring F[x] of univariate polynomials over a field F. For the sake of efficiency, and because many of the properties we verify are specific to matrices over a principal ideal domain, we cannot simply rely on previously-developed linear algebra protocols for matrices over a field. Our protocols are interactive, often randomized, and feature a constant number of rounds of communication between the Prover and Verifier. We seek to minimize the communication cost so that the amount of data sent during the protocol is significantly smaller than the size of the result being verified, which can be useful when combining protocols or in some multi-party settings. The main tools we use are reductions to existing linear algebra verification protocols and a new protocol to verify that a given vector is in the F[x]-row space of a given matrix.
We report the first observation of $K^{\star}(892)^{0}\toπK$ in relativistic heavy ion collisions. The transverse momentum spectrum of $(K^{\star0}+\bar{K}^{\star0})/2$ from central Au+Au collisions at $\sqrt{s_{_{NN}}}=130$ GeV is presented. The ratios of the $K^{\star0}$ yield derived from these data to the yields of negative hadrons, charged kaons, and $φ$ mesons have been measured in central and minimum bias collisions and compared with model predictions and comparable $e^{+}e^{-}$, $pp$, and $\bar{p}p$ results. The data indicate no dramatic reduction of $K^{\star0}$ production in relativistic heavy ion collisions despite expected losses due to rescattering effects.
The STAR experiment reports the first measurement of the $^4_Λ\hbox{He}$ hyper-nuclei yield as a function of rapidity and transverse momentum in 0-50% central Au+Au collisions at $\sqrt{s_{\rm{NN}}} =$ 3 GeV. The $^4_Λ\hbox{He}$ is reconstructed through its three-body decay channel, $^4_Λ\rm{He} \rightarrow {}^{3}\rm{He} + \rm{p} + π^-$, with a statistical significance of about 9.5 standard deviations. We find that the yield of $^4_Λ\hbox{He}$ as a function of rapidity is consistent with that of $^4_Λ\hbox{H}$, and the rapidity-dependent yield ratio of $^4_Λ\hbox{He}$/$^4_Λ\hbox{H}$ is consistent with that of $^3$He/t. All the measurements, as well as the transverse-momentum spectra, can be reasonably described by the JAM with a coalescence afterburner, suggesting a coalescence-based formation scenario for hyper-nuclei at this energy. The canonical thermal model reproduces the observed yield ratios but overpredicts the absolute hyper-nuclei yields.
Secure communication has achieved a new dimension with the advent of the schemes of quantum key distribution (QKD) as in contrast to classical cryptography, quantum cryptography can provide unconditional security. However, a successful implementation of a scheme of QKD requires identity authentication as a prerequisite. A security loophole in the identity authentication scheme may lead to the vulnerability of the entire secure communication scheme. Consequently, identity authentication is extremely important and in the last three decades several schemes for identity authentication, using quantum resources have been proposed. The chronological development of these protocols, which are now referred to as quantum identity authentication (QIA) protocols, are briefly reviewed here with specific attention to the causal connection involved in their development. The existing protocols are classified on the basis of the required quantum resources and their relative merits and demerits are analyzed. Further, in the process of the classification of the protocols for QIA, it's observed that the existing protocols can also be classified in a few groups based on the inherent computational tasks
The first bound star-forming systems in the universe are predicted to form at redshifts of about 30 and to have masses of the order of 10^6 M_sun. Although their sizes and masses are similar to those of present star-forming regions, their temperatures are expected to be much higher because cooling is provided only by trace amounts of molecular hydrogen. Several recent simulations of the collapse and fragmentation of primordial clouds have converged on a thermal regime where the density is about 10^3-10^4 cm^{-3} and the temperature is about 300 K; under these conditions the Jeans mass is of the order of 10^3 M_sun, and all of the simulations show the formation of clumps with masses of this order. The temperatures in these clumps subsequently rise slowly as they collapse, so little if any further fragmentation is expected. As a result, the formation of predominantly massive or very massive stars is expected, and star formation with a normal present-day IMF seems very unlikely. The most massive early stars are expected to collapse to black holes, and these in turn are predicted to end up concentrated near the centers of present-day large galaxies. Such black holes may play a role in
We report on the observed signals of ${K^{\star0}(892)}\toπK$ and $φ(1020)\to K^{+}K^{-}$ using the mixed-event method with powerful statistics from the large acceptance and highly efficient STAR TPC. Preliminary results from the first observation of such states from the year-one STAR data in $\sqrt{s_{NN}}=130$ GeV Au-Au collisions are presented. The $K^{\star0}/h^{-}$ ratios with an assumed $K^{\star0}$ $p_{T}$ inverse slope of 300MeV are compatible with that from pp at ISR. For 14% central Au+Au collisions, we observe $K^{\star0}/h^{-}=0.060\pm0.007(stat)$ and $\bar{K^{\star0}}/h^{-}=0.058\pm0.007(stat)$. We show that $\barΛ/Λ=0.77\pm0.07(stat)$ from this method is consistent with the measurement via decay topology.
Differential privacy (DP) is widely employed to provide privacy protection for individuals by limiting information leakage from the aggregated data. Two well-known models of DP are the central model and the local model. The former requires a trustworthy server for data aggregation, while the latter requires individuals to add noise, significantly decreasing the utility of aggregated results. Recently, many studies have proposed to achieve DP with Secure Multi-party Computation (MPC) in distributed settings, namely, the distributed model, which has utility comparable to central model while, under specific security assumptions, preventing parties from obtaining others' information. One challenge of realizing DP in distributed model is efficiently sampling noise with MPC. Although many secure sampling methods have been proposed, they have different security assumptions and isolated theoretical analyses. There is a lack of experimental evaluations to measure and compare their performances. We fill this gap by benchmarking existing sampling protocols in MPC and performing comprehensive measurements of their efficiency. First, we present a taxonomy of the underlying techniques of these s
Forward particle production and correlation measurements at RHIC can probe low-$x$ gluons. The suppression observed in back-to-back forward $π^{0}$+forward $π^{0}$ correlations at STAR in central d+Au collisions at STAR is consistent with a prediction of the Color Glass Condensate (CGC) calculation, indicating the gold nucleus probed at such low-$x$ is in a dense gluon state. The forward $π^{0}$ + near-forward jet-like cluster azimuthal correlations in 200 GeV p+p and d+Au collisions at STAR are studied, which are sensitive to the intermediate x region between forward+mid-rapidity correlations and forward+forward correlations. Together with the other measurements from STAR, which probe different regions of x, forward+near-forward di-hadron correlations can provide information to understand how sharp is the transition from dilute parton gas to dense gluon state.
We present a protocol to evaluate ChatGPT's ability to generate disease-centric biomedical associations. It outlines how we generate the associations, validate the biological entities using biomedical ontologies, and verify associations using literature. The protocol includes a self-consistency strategy to assess generative reliability across ChatGPT models. To address ontology exact-match limitations, we provide a use case performing semantic verification through a workflow enabled by Retrieval-Augmented Generation (RAG) powered by open-source large language models (LLMs). This enables LLMs to establish truth over content generated by other LLMs and expose hallucination.
The high-level contribution of this paper is a simulation-based detailed performance comparison of three different classes of routing protocols for mobile ad hoc networks: stability-based routing, power-aware routing and load-balanced routing. We choose the Flow-Oriented Routing protocol (FORP), the traffic interference based Load Balancing Routing (LBR) protocol and Min-Max Battery Cost Routing (MMBCR) as representatives of the stability-based routing, load-balancing and power-aware routing protocols respectively. Among the three routing protocols, FORP incurs the least number of route transitions; while LBR incurs the smallest hop count and lowest end-to-end delay per data packet. Energy consumed per node is the least for MMBCR, closely followed by LBR. MMBCR is the most fair in terms of node usage and hence it incurs the largest time for first node failure. FORP tends to repeatedly use nodes lying on the stable path and hence is the most unfair of the three routing protocols and it incurs the smallest value for the time of first node failure. As we measure the failure times of up to the first five nodes in the network, we observe that LBR incurs the maximum improvement in the li