المؤلفون: Gué, Jordan, Hees, Aurélien, Wolf, Peter, Savalle, Etienne, Chevalier, Laurent, Brun, Pierre

مصطلحات موضوعية: High Energy Physics - Experiment, Astrophysics - Cosmology and Nongalactic Astrophysics

الوصف: A vector dark matter candidate, also known as dark photon, would induce an oscillating electric field through kinetic mixing. One detection strategy uses a spherical reflector to focus the induced emission at its center of curvature. On one hand, we investigate the effects of diffraction in this type of experiment from an analytical standpoint, making use of the Kirchhoff integral theorem in the low-curvature dish limit. On the other hand, we estimate the impact of mode-matching, in the case of detection by a pyramidal horn antenna. We show that the expected signal intensity can be significantly reduced compared to usual estimates. Our method is applied to the re-interpretation of the SHUKET experiment data, the results of which are shown to be degraded by a factor of $\sim$~50 due to both diffraction and mode-matching. The analytical method allows optimizing some experimental parameters to gain sensitivity in future runs. Our results can be applied to any dish antenna experiment using a low curvature reflector.
Comment: 12+3 pages, 6 figures

الوصول الحر: http://arxiv.org/abs/2403.13448Test

المؤلفون: Alorda, Abigail, Cesarz, Taylor, MacIntosh, Tracy, Cohen, Stephanie, Gue, Shayne

المصدر: Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health. 25(3.1)

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/4k52w8r3Test

المؤلفون: Cesarz, Taylor, Cohen, Stephanie, Voter, Mitchell, Gue, Shayne

المصدر: Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health. 25(3.1)

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/98n4f0bwTest

المؤلفون: Alorda, Abigail, Cesarz, Taylor, Littell, Jonathan, Hashemi, Kiana, Ali, Rifa, Sia, Marianne, Carrazana, Anela, Cohen, Stephanie, Gue, Shayne

المصدر: Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health. 25(3.1)

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/2jf4v7rrTest

المؤلفون: Mejias, Darielys, Gue, Shayne

المصدر: Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health. 25(3.1)

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/21d9t780Test

المؤلفون: Diers, Natalie, Cohen, Stephanie, Tassone, Maria, Gue, Shayne

المصدر: Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health. 25(3.1)

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/421590p6Test

المؤلفون: Gué, Jordan, Hees, Aurélien, Wolf, Peter

مصطلحات موضوعية: High Energy Physics - Phenomenology, Astrophysics - Cosmology and Nongalactic Astrophysics, General Relativity and Quantum Cosmology, Physics - Atomic Physics

الوصف: We present a theoretical investigation of the expected experimental signals produced by freely falling atoms with time oscillating mass and transition frequency. These oscillations could be produced in a variety of models, in particular, models of scalar dark matter (DM) non universally coupled to the standard matter (SM) such as axion-like particles (ALP) and dilatons. Performing complete and rigorous calculations, we show that, on one hand, two different atomic species would accelerate at a different rate, and on the other hand, they would produce a non-zero differential phase shift in atom interferometers (AI). The former would produce observable signals in equivalence principle tests like the recent MICROSCOPE mission, and we provide a corresponding sensitivity estimate, showing that MICROSCOPE can reach beyond the best existing searches in the ALP case. We also compare the expected sensitivity of two future AI experiments, namely the AION-10 gradiometer and an isotope differential AI considered for MAGIS-100, that we will refer to as SPID. We show that the SPID setup would be more sensitive to these dark matter fields compared to the gradiometer one, assuming equivalent experimental parameters.
Comment: 30 pages, 7 figures, 2 tables

الوصول الحر: http://arxiv.org/abs/2401.14742Test

المؤلفون: Lee, Jae Hyoung, Lee, Gue Myung, Pham, Tien Son

مصطلحات موضوعية: Mathematics - Optimization and Control, 14P05, 14P10, 90C26, 90C30

الوصف: Consider the problem of minimizing a lower semi-continuous semi-algebraic function $f \colon \mathbb{R}^n \to \mathbb{R} \cup \{+\infty\}$ on an unbounded closed semi-algebraic set $S \subset \mathbb{R}^n.$ Employing adequate tools of semi-algebraic geometry, we first establish some properties of the tangency variety of the restriction of $f$ on $S.$ Then we derive verifiable necessary and sufficient conditions for the existence of optimal solutions of the problem as well as the boundedness from below and coercivity of the restriction of $f$ on $S.$ We also present a computable formula for the optimal value of the problem.

الوصول الحر: http://arxiv.org/abs/2308.05349Test

المؤلفون: Gué, Jordan, Hees, Aurélien, Lodewyck, Jérôme, Targat, Rodolphe Le, Wolf, Peter

مصطلحات موضوعية: Physics - Atomic Physics, General Relativity and Quantum Cosmology, High Energy Physics - Phenomenology

الوصف: We propose a novel experiment to search for dark matter, based on the application of an electric field inside a microwave cavity and electrometry using Rydberg atoms. We show that this kind of experiment could be extremely useful for detecting specific dark matter candidates, namely massive vector fields coupled to the photon field, more commonly known as dark photons. Such a massive vector field is a good candidate for dark matter. Using realistic experimental parameters we show that such an experiment could improve the current constraint on the coupling constant of the dark photons to Standard Model photons in the 1~$\mu$eV to 10~$\mu$eV mass range, with the possibility of tuning the maximum sensitivity via the cavity size. The main limiting factors on the sensitivity of the experiment are the amplitude stability of the applied field and the measurement uncertainty of the electric field by the atoms.
Comment: 14 pages, 3 figures, version accepted for publication in Phys. Rev. D

الوصول الحر: http://arxiv.org/abs/2305.11671Test

المؤلفون: Jae-Woong Park, Byung-Jin Park, Jin-Seok Lee, Eun-Jung Lee, Yo-Chan Ahn, Chang-Gue Son

المصدر: Journal of Translational Medicine, Vol 22, Iss 1, Pp 1-12 (2024)

مصطلحات موضوعية: Myalgic encephalomyelitis (ME), Chronic fatigue syndrome (CFS), Fatigue severity, Meta-analysis, Medicine

الوصف: Abstract Background Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating illness medically unexplained, affecting approximately 1% of the global population. Due to the subjective complaint, assessing the exact severity of fatigue is a clinical challenge, thus, this study aimed to produce comprehensive features of fatigue severity in ME/CFS patients. Methods We systematically extracted the data for fatigue levels of participants in randomized controlled trials (RCTs) targeting ME/CFS from PubMed, Cochrane Library, Web of Science, and CINAHL throughout January 31, 2024. We normalized each different measurement to a maximum 100-point scale and performed a meta-analysis to assess fatigue severity by subgroups of age, fatigue domain, intervention, case definition, and assessment tool, respectively. Results Among the total of 497 relevant studies, 60 RCTs finally met our eligibility criteria, which included a total of 7088 ME/CFS patients (males 1815, females 4532, and no information 741). The fatigue severity of the whole 7,088 patients was 77.9 (95% CI 74.7–81.0), showing 77.7 (95% CI 74.3–81.0) from 54 RCTs in 6,706 adults and 79.6 (95% CI 69.8–89.3) from 6 RCTs in 382 adolescents. Regarding the domain of fatigue, ‘cognitive’ (74.2, 95% CI 65.4–83.0) and ‘physical’ fatigue (74.3, 95% CI 68.3–80.3) were a little higher than ‘mental’ fatigue (70.1, 95% CI 64.4–75.8). The ME/CFS participants for non-pharmacological intervention (79.1, 95% CI 75.2–83.0) showed a higher fatigue level than those for pharmacological intervention (75.5, 95% CI 70.0–81.0). The fatigue levels of ME/CFS patients varied according to diagnostic criteria and assessment tools adapted in RCTs, likely from 54.2 by ICC (International Consensus Criteria) to 83.6 by Canadian criteria and 54.2 by MFS (Mental Fatigue Scale) to 88.6 by CIS (Checklist Individual Strength), respectively. Conclusions This systematic review firstly produced comprehensive features of fatigue severity in patients with ME/CFS. Our data will provide insights for clinicians in diagnosis, therapeutic assessment, and patient management, as well as for researchers in fatigue-related investigations.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/1479-5876Test

الوصول الحر: https://doaj.org/article/23ac434a9d274109bdd968b95cffa04cTest