767 research outputs found

    Discovery reach for wino and higgsino dark matter with a disappearing track signature at a 100 TeV pppp collider

    Full text link
    Within the theory of supersymmetry, the lightest neutralino is a dark matter candidate and is often assumed to be the lightest supersymmetric particle (LSP) as well. If the neutral wino or higgsino is dark matter, the upper limit of the LSP mass is determined by the observed relic density of dark matter. If the LSP is a nearly-pure neutral state of the wino or higgsino, the lightest chargino state is expected to have a significant lifetime due to a tiny mass difference between the LSP and the chargino. This article presents discovery potential of the 100 TeV future circular hadron collider (FCC) for the wino and higgsino dark matter using a disappearing-track signature. The search strategy to extend the discovery reach to the thermal limits of wino/higgsino dark matter is discussed with detailed studies on the background rate and the reference design of the FCC-hadron detector under possible running scenarios of the FCC-hadron machine. A proposal of modifying the detector layout and several ideas to improve the sensitivity further are also discussed.Comment: 10 pages, 7 figures, 4 table

    Resolution enhancement of one-dimensional molecular wavefunctions in plane-wave basis via quantum machine learning

    Full text link
    Super-resolution is a machine-learning technique in image processing which generates high-resolution images from low-resolution images. Inspired by this approach, we perform a numerical experiment of quantum machine learning, which takes low-resolution (low plane-wave energy cutoff) one-particle molecular wavefunctions in plane-wave basis as input and generates high-resolution (high plane-wave energy cutoff) wavefunctions in fictitious one-dimensional systems, and study the performance of different learning models. We show that the trained models can generate wavefunctions having higher fidelity values with respect to the ground-truth wavefunctions than a simple linear interpolation, and the results can be improved both qualitatively and quantitatively by including data-dependent information in the ansatz. On the other hand, the accuracy of the current approach deteriorates for wavefunctions calculated in electronic configurations not included in the training dataset. We also discuss the generalization of this approach to many-body electron wavefunctions.Comment: 13 pages, 18 figure

    Steady shocks around black holes produced by sub-keplerian flows with negative energy

    Get PDF
    We discuss a special case of formation of axisymmetric shocks in the accretion flow of ideal gas onto a Schwarzschild black hole: when the total energy of the flow is negative. The result of our analysis enlarges the parameter space for which these steady shocks are exhibited in the accretion of gas rotating around relativistic stellar objects. Since keplerian disks have negative total energy, we guess that, in this energy range, the production of the shock phenomenon might be easier than in the case of positive energy. So our outcome reinforces the view that sub-keplerian flows of matter may significantly affect the physics of the high energy radiation emission from black hole candidates. We give a simple procedure to obtain analytically the position of the shocks. The comparison of the analytical results with the data of 1D and 2D axisymmetric numerical simulations confirms that the shocks form and are stable.Comment: 5 pages, 5 figures, accepted by MNRAS on 10 November 200

    Quantum Gate Pattern Recognition and Circuit Optimization for Scientific Applications

    Full text link
    There is no unique way to encode a quantum algorithm into a quantum circuit. With limited qubit counts, connectivities, and coherence times, circuit optimization is essential to make the best use of near-term quantum devices. We introduce two separate ideas for circuit optimization and combine them in a multi-tiered quantum circuit optimization protocol called AQCEL. The first ingredient is a technique to recognize repeated patterns of quantum gates, opening up the possibility of future hardware co-optimization. The second ingredient is an approach to reduce circuit complexity by identifying zero- or low-amplitude computational basis states and redundant gates. As a demonstration, AQCEL is deployed on an iterative and efficient quantum algorithm designed to model final state radiation in high energy physics. For this algorithm, our optimization scheme brings a significant reduction in the gate count without losing any accuracy compared to the original circuit. Additionally, we have investigated whether this can be demonstrated on a quantum computer using polynomial resources. Our technique is generic and can be useful for a wide variety of quantum algorithms.Comment: 22 pages, 16 figure

    Increased Expression of Proliferating Cell Nuclear Antigen in Rejecting Rat Lung Allografts

    Get PDF
    The aim of this study was to investigate the expression of proliferating cell nuclear antigen (PCNA) as an index of cell proliferation in the Brown Norway (BN) to Lewis (LEW) rat lung allograft model.Following transplantation of BN left lungs into LEW recipients, counts of PCNA-positive cells in the perivascular cellular infiltrate and bronchus-associated lymphoid tissue (BALT) were compared with the histological grade of rejection. Lungs were excised on postoperative days 3 and 5. LEW-to-LEW donor-recipient transplantation was performed as a control. Routinely processed, paraffinembedded sections were selected and stained with PCNA. The PCNA index (% of nuclei positive for PCNA) in the BALT was significantly higher in allograft (19.1%, p < 0.05) compared with isograft (4.2%) at 3 days following transplantation. Similarly, the PCNA index was also greater in the perivascular cellular infiltrates of rejecting lungs (23.9% at 3 days, 31.6% at 5 days). These findings indicate that the cells stimulated by the rejection reaction could be increase the expression of PCNA, and the increasing severity of rejection was paralleled by an increase in the number of PCNA-positive cells. In conclusion, PCNA may be a useful marker of acute cellular rejection in lung allografts
    corecore