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Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Bhimani KH, Blalock E, Bos B, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Clark ML, Cuesta C, Detwiler JA, Efremenko Y, Ejiri H, Elliott SR, Giovanetti GK, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Henning R, Hervas Aguilar D, Hoppe EW, Hostiuc A, Kidd MF, Kim I, Kouzes RT, Lannen V TE, Li A, Lopez AM, López-Castaño JM, Martin EL, Martin RD, Massarczyk R, Meijer SJ, Mertens S, Oli TK, Othman G, Paudel LS, Pettus W, Poon AWP, Radford DC, Rager J, Reine AL, Rielage K, Ruof NW, Schaper DC, Tedeschi D, Varner RL, Vasilyev S, Wilkerson JF, Wiseman C, Xu W, Yu CH, Zhu BX. Exotic Dark Matter Search with the Majorana Demonstrator. PHYSICAL REVIEW LETTERS 2024; 132:041001. [PMID: 38335333 DOI: 10.1103/physrevlett.132.041001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 09/08/2023] [Accepted: 11/09/2023] [Indexed: 02/12/2024]
Abstract
With excellent energy resolution and ultralow-level radiogenic backgrounds, the high-purity germanium detectors in the Majorana Demonstrator enable searches for several classes of exotic dark matter (DM) models. In this work, we report new experimental limits on keV-scale sterile neutrino DM via the transition magnetic moment from conversion to active neutrinos ν_{s}→ν_{a}. We report new limits on fermionic dark matter absorption (χ+A→ν+A) and sub-GeV DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), and new exclusion limits for bosonic dark matter (axionlike particles and dark photons). These searches utilize the (1-100)-keV low-energy region of a 37.5-kg y exposure collected by the Demonstrator between May 2016 and November 2019 using a set of ^{76}Ge-enriched detectors whose surface exposure time was carefully controlled, resulting in extremely low levels of cosmogenic activation.
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Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Bhimani KH, Blalock E, Bos B, Busch M, Buuck M, Caldwell TS, Christofferson CD, Chu PH, Clark ML, Cuesta C, Detwiler JA, Efremenko Y, Ejiri H, Elliott SR, Giovanetti GK, Goett J, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Henning R, Hervas Aguilar D, Hoppe EW, Hostiuc A, Kim I, Kouzes RT, Lannen V TE, Li A, López-Castaño JM, Massarczyk R, Meijer SJ, Meijer W, Oli TK, Paudel LS, Pettus W, Poon AWP, Radford DC, Reine AL, Rielage K, Rouyer A, Ruof NW, Schaper DC, Schleich SJ, Smith-Gandy TA, Tedeschi D, Thompson JD, Varner RL, Vasilyev S, Watkins SL, Wilkerson JF, Wiseman C, Xu W, Yu CH, Alves DSM, Hebenstiel L, Ramani H. Constraints on the Decay of ^{180m}Ta. PHYSICAL REVIEW LETTERS 2023; 131:152501. [PMID: 37897780 DOI: 10.1103/physrevlett.131.152501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 08/15/2023] [Accepted: 09/12/2023] [Indexed: 10/30/2023]
Abstract
^{180m}Ta is a rare nuclear isomer whose decay has never been observed. Its remarkably long lifetime surpasses the half-lives of all other known β and electron capture decays due to the large K-spin differences and small energy differences between the isomeric and lower-energy states. Detecting its decay presents a significant experimental challenge but could shed light on neutrino-induced nucleosynthesis mechanisms, the nature of dark matter, and K-spin violation. For this study, we repurposed the Majorana Demonstrator, an experimental search for the neutrinoless double-beta decay of ^{76}Ge using an array of high-purity germanium detectors, to search for the decay of ^{180m}Ta. More than 17 kg, the largest amount of tantalum metal ever used for such a search, was installed within the ultralow-background detector array. In this Letter, we present results from the first year of Ta data taking and provide an updated limit for the ^{180m}Ta half-life on the different decay channels. With new limits up to 1.5×10^{19} yr, we improved existing limits by 1-2 orders of magnitude which are the most sensitive searches for a single β and electron capture decay ever achieved. Over all channels, the decay can be excluded for T_{1/2}<0.29×10^{18} yr.
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Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Bhimani KH, Blalock E, Bos B, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Clark ML, Cuesta C, Detwiler JA, Efremenko Y, Ejiri H, Elliott SR, Giovanetti GK, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Henning R, Hervas Aguilar D, Hoppe EW, Hostiuc A, Kim I, Kouzes RT, Lannen V TE, Li A, Lopez AM, López-Castaño JM, Martin EL, Martin RD, Massarczyk R, Meijer SJ, Oli TK, Othman G, Paudel LS, Pettus W, Poon AWP, Radford DC, Reine AL, Rielage K, Ruof NW, Tedeschi D, Varner RL, Vasilyev S, Wilkerson JF, Wiseman C, Xu W, Yu CH, Zhu BX. Erratum: Search for Spontaneous Radiation from Wave Function Collapse in the Majorana Demonstrator [Phys. Rev. Lett. 129, 080401 (2022)]. PHYSICAL REVIEW LETTERS 2023; 130:239902. [PMID: 37354428 DOI: 10.1103/physrevlett.130.239902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Indexed: 06/26/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.129.080401.
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Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Barton PJ, Bhimani KH, Blalock E, Bos B, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Clark ML, Cuesta C, Detwiler JA, Efremenko Y, Ejiri H, Elliott SR, Giovanetti GK, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Henning R, Hervas Aguilar D, Hoppe EW, Hostiuc A, Kidd MF, Kim I, Kouzes RT, Lannen V TE, Li A, Lopez AM, López-Castaño JM, Martin EL, Martin RD, Massarczyk R, Meijer SJ, Mertens S, Oli TK, Othman G, Paudel LS, Pettus W, Poon AWP, Radford DC, Reine AL, Rielage K, Ruof NW, Schaper DC, Tedeschi D, Varner RL, Vasilyev S, Wilkerson JF, Wiseman C, Xu W, Yu CH, Zhu BX. Final Result of the Majorana Demonstrator's Search for Neutrinoless Double-β Decay in ^{76}Ge. PHYSICAL REVIEW LETTERS 2023; 130:062501. [PMID: 36827565 DOI: 10.1103/physrevlett.130.062501] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 11/09/2022] [Accepted: 12/16/2022] [Indexed: 06/18/2023]
Abstract
The Majorana Demonstrator searched for neutrinoless double-β decay (0νββ) of ^{76}Ge using modular arrays of high-purity Ge detectors operated in vacuum cryostats in a low-background shield. The arrays operated with up to 40.4 kg of detectors (27.2 kg enriched to ∼88% in ^{76}Ge). From these measurements, the Demonstrator has accumulated 64.5 kg yr of enriched active exposure. With a world-leading energy resolution of 2.52 keV FWHM at the 2039 keV Q_{ββ} (0.12%), we set a half-life limit of 0νββ in ^{76}Ge at T_{1/2}>8.3×10^{25} yr (90% C.L.). This provides a range of upper limits on m_{ββ} of (113-269) meV (90% C.L.), depending on the choice of nuclear matrix elements.
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Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Bhimani KH, Blalock E, Bos B, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Clark ML, Cuesta C, Detwiler JA, Efremenko Y, Ejiri H, Elliott SR, Giovanetti GK, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Henning R, Hervas Aguilar D, Hoppe EW, Hostiuc A, Kim I, Kouzes RT, Lannen V TE, Li A, Lopez AM, López-Castaño JM, Martin EL, Martin RD, Massarczyk R, Meijer SJ, Oli TK, Othman G, Paudel LS, Pettus W, Poon AWP, Radford DC, Reine AL, Rielage K, Ruof NW, Tedeschi D, Varner RL, Vasilyev S, Wilkerson JF, Wiseman C, Xu W, Yu CH, Zhu BX. Search for Spontaneous Radiation from Wave Function Collapse in the Majorana Demonstrator. PHYSICAL REVIEW LETTERS 2022; 129:080401. [PMID: 36053678 DOI: 10.1103/physrevlett.129.080401] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 06/14/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
The Majorana Demonstrator neutrinoless double-beta decay experiment comprises a 44 kg (30 kg enriched in ^{76}Ge) array of p-type, point-contact germanium detectors. With its unprecedented energy resolution and ultralow backgrounds, Majorana also searches for rare event signatures from beyond standard model physics in the low energy region below 100 keV. In this Letter, we test the continuous spontaneous localization (CSL) model, one of the mathematically well-motivated wave function collapse models aimed at solving the long-standing unresolved quantum mechanical measurement problem. While the CSL predicts the existence of a detectable radiation signature in the x-ray domain, we find no evidence of such radiation in the 19-100 keV range in a 37.5 kg-y enriched germanium exposure collected between December 31, 2015, and November 27, 2019, with the Demonstrator. We explored both the non-mass-proportional (n-m-p) and the mass-proportional (m-p) versions of the CSL with two different assumptions: that only the quasifree electrons can emit the x-ray radiation and that the nucleus can coherently emit an amplified radiation. In all cases, we set the most stringent upper limit to date for the white CSL model on the collapse rate, λ, providing a factor of 40-100 improvement in sensitivity over comparable searches. Our limit is the most stringent for large parts of the allowed parameter space. If the result is interpreted in terms of the Diòsi-Penrose gravitational wave function collapse model, the lower bound with a 95% confidence level is almost an order of magnitude improvement over the previous best limit.
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Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Bhimani KH, Blalock E, Bos B, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Clark ML, Cuesta C, Detwiler JA, Efremenko Y, Ejiri H, Elliott SR, Giovanetti GK, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Henning R, Hervas Aguilar D, Hoppe EW, Hostiuc A, Kidd MF, Kim I, Kouzes RT, Lannen V TE, Li A, Lopez AM, López-Castaño JM, Martin EL, Martin RD, Massarczyk R, Meijer SJ, Oli TK, Othman G, Paudel LS, Pettus W, Poon AWP, Radford DC, Reine AL, Rielage K, Ruof NW, Schaper DC, Tedeschi D, Varner RL, Vasilyev S, Wilkerson JF, Wiseman C, Xu W, Yu CH, Zhu BX. Search for Solar Axions via Axion-Photon Coupling with the Majorana Demonstrator. PHYSICAL REVIEW LETTERS 2022; 129:081803. [PMID: 36053699 DOI: 10.1103/physrevlett.129.081803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
Axions were originally proposed to explain the strong-CP problem in QCD. Through axion-photon coupling, the Sun could be a major source of axions, which could be measured in solid state detection experiments with enhancements due to coherent Primakoff-Bragg scattering. The Majorana Demonstrator experiment has searched for solar axions with a set of ^{76}Ge-enriched high purity germanium detectors using a 33 kg-yr exposure collected between January, 2017 and November, 2019. A temporal-energy analysis gives a new limit on the axion-photon coupling as g_{aγ}<1.45×10^{-9} GeV^{-1} (95% confidence level) for axions with mass up to 100 eV/c^{2}. This improves laboratory-based limits between about 1 eV/c^{2} and 100 eV/c^{2}.
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Pitta Villasboa GM, Frontanilla T, Servián L, Ortiz X, Henning R, Ortiz Galeano I. Prevalence of antinuclear antibodies in apparently healthy residents of the Hospital de Clínicas, San Lorenzo. REVISTA VIRTUAL DE LA SOCIEDAD PARAGUAYA DE MEDICINA INTERNA 2022. [DOI: 10.18004/rvspmi/2312-3893/2022.09.01.71] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Bertrand FE, Blalock E, Bos B, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Clark ML, Cuesta C, Detwiler JA, Drobizhev A, Edwards TR, Edwins DW, Edzards F, Efremenko Y, Elliott SR, Gilliss T, Giovanetti GK, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Hegedus RJ, Henning R, Aguilar DH, Hoppe EW, Hostiuc A, Kim I, Kouzes RT, Lopez AM, López-Castaño JM, Martin EL, Martin RD, Massarczyk R, Meijer SJ, Mertens S, Myslik J, Oli TK, Othman G, Pettus W, Poon AWP, Radford DC, Rager J, Reine AL, Rielage K, Ruof NW, Saykı B, Schönert S, Stortini MJ, Tedeschi D, Varner RL, Vasilyev S, Wilkerson JF, Willers M, Wiseman C, Xu W, Yu CH, Zhu BX. α -event characterization and rejection in point-contact HPGe detectors. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2022; 82:226. [PMID: 35310515 PMCID: PMC8921096 DOI: 10.1140/epjc/s10052-022-10161-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
P-type point contact (PPC) HPGe detectors are a leading technology for rare event searches due to their excellent energy resolution, low thresholds, and multi-site event rejection capabilities. We have characterized a PPC detector's response to α particles incident on the sensitive passivated and p+ surfaces, a previously poorly-understood source of background. The detector studied is identical to those in the Majorana Demonstrator experiment, a search for neutrinoless double-beta decay ( 0 ν β β ) in76 Ge. α decays on most of the passivated surface exhibit significant energy loss due to charge trapping, with waveforms exhibiting a delayed charge recovery (DCR) signature caused by the slow collection of a fraction of the trapped charge. The DCR is found to be complementary to existing methods of α identification, reliably identifying α background events on the passivated surface of the detector. We demonstrate effective rejection of all surface α events (to within statistical uncertainty) with a loss of only 0.2% of bulk events by combining the DCR discriminator with previously-used methods. The DCR discriminator has been used to reduce the background rate in the 0 ν β β region of interest window by an order of magnitude in the Majorana Demonstrator and will be used in the upcoming LEGEND-200 experiment.
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Cardozo Lomaquiz CD, Frontanilla T, Scavone N, Fretes A, Torales N, Pereira ME, Mino de Kaspar H, Ortiz X, Henning R. Rapid growth atypical mycobacteria infection associated with growth hormone injections: a case report. Access Microbiol 2022; 3:000280. [PMID: 35018325 PMCID: PMC8742584 DOI: 10.1099/acmi.0.000280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 07/23/2021] [Indexed: 11/18/2022] Open
Abstract
Introduction Infections caused by fast growing mycobacteria have increased markedly worldwide. They are normally associated with trauma, surgery or cosmetic interventions. Paraguay has a deficit in sanitary control including clinics, private practices, and aesthetic centres. This situation is accompanied by the easy access to drugs, which leads to the performance of exclusively medical aesthetic procedures by people without professional knowledge or training. Case report A 26-year-old female patient comes to a medical consultation with pain and bruising in the abdominal area with more than 3 months of progression, without fever or apparent cause. Later, she confessed to the application of subcutaneous injections of ‘growth hormones’ at the gym. Excisional biopsy of the lesions was carried out for anatomopathological and microbiological studies. In addition, the use of polymerase chain reaction analysis was indicated because of the strong suspicion of an atypical mycobacterial infection. The Ziehl-Neelsen staining was negative for BAAR, and the PAS-Hematoxylin negative for fungal elements. When performing the culture, the growth of atypical mycobacteria was observed on chocolate and blood agar medium culture. Through the polymerase chain reaction study, it was possible to identify the atypical mycobacterium as ‘Mycobacterium abscessus’. Conclusion The irresponsible application of medications by people without professional authorization or biosafety precautions can lead to the development atypical infections that are difficult to diagnose and treat. This situation could lead to serious complications and even death.
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Nguyen J, Kesper K, Kräling G, Birk C, Mross P, Hofeditz N, Höchst J, Lampe P, Penning A, Leutenecker-Twelsiek B, Schindler C, Buchenauer H, Geisel D, Sommer C, Henning R, Wallot P, Wiesmann T, Beutel B, Schneider G, Castro-Camus E, Koch M. Repurposing CPAP machines as stripped-down ventilators. Sci Rep 2021; 11:12204. [PMID: 34108549 PMCID: PMC8190155 DOI: 10.1038/s41598-021-91673-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 05/28/2021] [Indexed: 01/15/2023] Open
Abstract
The worldwide shortage of medical-grade ventilators is a well-known issue, that has become one of the central topics during the COVID-19 pandemic. Given that these machines are expensive and have long lead times, one approach is to vacate them for patients in critical conditions while patients with mild to moderate symptoms are treated with stripped-down ventilators. We propose a mass-producible solution that can create such ventilators with minimum effort. The central part is a module that can be attached to CPAP machines and repurpose them as low-pressure ventilators. Here, we describe the concept and first measurements which underline the potential of our solution. Our approach may serve as a starting point for open-access ventilator technologies.
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Henry L, Panman MR, Isaksson L, Claesson E, Kosheleva I, Henning R, Westenhoff S, Berntsson O. Real-time tracking of protein unfolding with time-resolved x-ray solution scattering. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2020; 7:054702. [PMID: 32984436 PMCID: PMC7511240 DOI: 10.1063/4.0000013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 08/17/2020] [Indexed: 05/14/2023]
Abstract
The correct folding of proteins is of paramount importance for their function, and protein misfolding is believed to be the primary cause of a wide range of diseases. Protein folding has been investigated with time-averaged methods and time-resolved spectroscopy, but observing the structural dynamics of the unfolding process in real-time is challenging. Here, we demonstrate an approach to directly reveal the structural changes in the unfolding reaction. We use nano- to millisecond time-resolved x-ray solution scattering to probe the unfolding of apomyoglobin. The unfolding reaction was triggered using a temperature jump, which was induced by a nanosecond laser pulse. We demonstrate a new strategy to interpret time-resolved x-ray solution scattering data, which evaluates ensembles of structures obtained from molecular dynamics simulations. We find that apomyoglobin passes three states when unfolding, which we characterize as native, molten globule, and unfolded. The molten globule dominates the population under the conditions investigated herein, whereas native and unfolded structures primarily contribute before the laser jump and 30 μs after it, respectively. The molten globule retains much of the native structure but shows a dynamic pattern of inter-residue contacts. Our study demonstrates a new strategy to directly observe structural changes over the cause of the unfolding reaction, providing time- and spatially resolved atomic details of the folding mechanism of globular proteins.
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Henry L, Berntsson O, Panman MR, Cellini A, Hughes AJ, Kosheleva I, Henning R, Westenhoff S. New Light on the Mechanism of Phototransduction in Phototropin. Biochemistry 2020; 59:3206-3215. [PMID: 32786255 DOI: 10.1021/acs.biochem.0c00324] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Phototropins are photoreceptor proteins that regulate blue light-dependent biological processes for efficient photosynthesis in plants and algae. The proteins consist of a photosensory domain that responds to the ambient light and an output module that triggers cellular responses. The photosensory domain of phototropin from Chlamydomonas reinhardtii contains two conserved LOV (light-oxygen-voltage) domains with flavin chromophores. Blue light triggers the formation of a covalent cysteine-flavin adduct and upregulates the phototropin kinase activity. Little is known about the structural mechanism that leads to kinase activation and how the two LOV domains contribute to this. Here, we investigate the role of the LOV1 domain from C. reinhardtii phototropin by characterizing the structural changes occurring after blue light illumination with nano- to millisecond time-resolved X-ray solution scattering. By structurally fitting the data with atomic models generated by molecular dynamics simulations, we find that adduct formation induces a rearrangement of the hydrogen bond network from the buried chromophore to the protein surface. In particular, the change in conformation and the associated hydrogen bonding of the conserved glutamine 120 induce a global movement of the β-sheet, ultimately driving a change in the electrostatic potential on the protein surface. On the basis of the change in the electrostatics, we propose a structural model of how LOV1 and LOV2 domains interact and regulate the full-length phototropin from C. reinhardtii. This provides a rationale for how LOV photosensor proteins function and contributes to the optimal design of optogenetic tools based on LOV domains.
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Alvis S, Arnquist I, Avignone F, Barabash A, Barton C, Basu V, Bertrand F, Bos B, Brudanin V, Busch M, Buuck M, Caldwell T, Chan YD, Christofferson C, Chu PH, Cuesta C, Detwiler J, Efremenko Y, Ejiri H, Elliott S, Gilliss T, Giovanetti G, Green M, Gruszko J, Guinn I, Guiseppe V, Haufe C, Hegedus R, Hehn L, Henning R, Hervas Aguilar D, Hoppe E, Howe M, Keeter K, Kidd M, Konovalov S, Kouzes R, Lopez A, Martin R, Massarczyk R, Meijer S, Mertens S, Myslik J, Othman G, Pettus W, Piliounis A, Poon A, Radford D, Rager J, Reine A, Rielage K, Ruof N, Shanks B, Shirchenko M, Tedeschi D, Varner R, Vasilyev S, White B, Wilkerson J, Wiseman C, Xu W, Yakushev E, Yu CH, Yumatov V, Zhitnikov I, Zhu B. Search for trinucleon decay in the Majorana Demonstrator. Int J Clin Exp Med 2019. [DOI: 10.1103/physrevd.99.072004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Alvis SI, Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Bertrand FE, Brudanin V, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Cuesta C, Detwiler JA, Dunagan C, Efremenko Y, Ejiri H, Elliott SR, Gilliss T, Giovanetti GK, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Hehn L, Henning R, Hoppe EW, Howe MA, Konovalov SI, Kouzes RT, Lopez AM, Martin RD, Massarczyk R, Meijer SJ, Mertens S, Myslik J, O'Shaughnessy C, Othman G, Pettus W, Poon AWP, Radford DC, Rager J, Reine AL, Rielage K, Robertson RGH, Ruof NW, Shanks B, Shirchenko M, Suriano AM, Tedeschi D, Varner RL, Vasilyev S, Vorren K, White BR, Wilkerson JF, Wiseman C, Xu W, Yakushev E, Yu CH, Yumatov V, Zhitnikov I, Zhu BX. First Limit on the Direct Detection of Lightly Ionizing Particles for Electric Charge as Low as e/1000 with the Majorana Demonstrator. PHYSICAL REVIEW LETTERS 2018; 120:211804. [PMID: 29883176 DOI: 10.1103/physrevlett.120.211804] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 04/23/2018] [Indexed: 06/08/2023]
Abstract
The Majorana Demonstrator is an ultralow-background experiment searching for neutrinoless double-beta decay in ^{76}Ge. The heavily shielded array of germanium detectors, placed nearly a mile underground at the Sanford Underground Research Facility in Lead, South Dakota, also allows searches for new exotic physics. Free, relativistic, lightly ionizing particles with an electrical charge less than e are forbidden by the standard model but predicted by some of its extensions. If such particles exist, they might be detected in the Majorana Demonstrator by searching for multiple-detector events with individual-detector energy depositions down to 1 keV. This search is background-free, and no candidate events have been found in 285 days of data taking. New direct-detection limits are set for the flux of lightly ionizing particles for charges as low as e/1000.
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Yu CH, Alvis S, Arnquist I, Avignone F, Barabash A, Barton C, Bertrand F, Bode T, Brudanin V, Busch M, Buuck M, Caldwell T, Chan YD, Christofferson C, Chu PH, Cuesta C, Detwiler J, Dunagan C, Efremenko Y, Ejiri H, Elliott S, Gilliss T, Giovanetti G, Green M, Gruszko J, Guinn I, Guiseppe V, Haufe C, Hehn L, Henning R, Hoppe E, Howe M, Keeter K, Kidd M, Konovalov S, Kouzes R, Lopez A, Martin R, Massarczyk R, Meijer S, Mertens S, Myslik J, Othman G, Pettus W, Poon A, Radford D, Rager J, Reine A, Rielage K, Ruof N, Shanks B, Shirchenko M, Suriano A, Tedeschi D, Varner R, Vasilyev S, Vetter K, Vorren K, White B, Wilkerson J, Wiseman C, Xu W, Yakushev E, Yumatov V, Zhitnikov I, Zhu B. The Majorana Demonstrator Status and Preliminary Results. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201817801006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The Majorana Collaboration is using an array of high-purity Ge detectors to search for neutrinoless double-beta decay in 76Ge. Searches for neutrinoless double-beta decay are understood to be the only viable experimental method for testing the Majorana nature of the neutrino. Observation of this decay would imply violation of lepton number, that neutrinos are Majorana in nature, and provide information on the neutrino mass. The Majorana Demonstrator comprises 44.1 kg of p-type point-contact Ge detectors (29.7 kg enriched in 76Ge) surrounded by a low-background shield system. The experiment achieved a high efficiency of converting raw Ge material to detectors and an unprecedented detector energy resolution of 2.5 keV FWHM at Qββ. The Majorana collaboration began taking physics data in 2016. This paper summarizes key construction aspects of the Demonstrator and shows preliminary results from initial data.
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Aalseth CE, Abgrall N, Aguayo E, Alvis SI, Amman M, Arnquist IJ, Avignone FT, Back HO, Barabash AS, Barbeau PS, Barton CJ, Barton PJ, Bertrand FE, Bode T, Bos B, Boswell M, Bradley AW, Brodzinski RL, Brudanin V, Busch M, Buuck M, Caldwell AS, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Collar JI, Combs DC, Cooper RJ, Cuesta C, Detwiler JA, Doe PJ, Dunmore JA, Efremenko Y, Ejiri H, Elliott SR, Fast JE, Finnerty P, Fraenkle FM, Fu Z, Fujikawa BK, Fuller E, Galindo-Uribarri A, Gehman VM, Gilliss T, Giovanetti GK, Goett J, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Hallin AL, Haufe CR, Hehn L, Henning R, Hoppe EW, Hossbach TW, Howe MA, Jasinski BR, Johnson RA, Keeter KJ, Kephart JD, Kidd MF, Knecht A, Konovalov SI, Kouzes RT, LaFerriere BD, Leon J, Lesko KT, Leviner LE, Loach JC, Lopez AM, Luke PN, MacMullin J, MacMullin S, Marino MG, Martin RD, Massarczyk R, McDonald AB, Mei DM, Meijer SJ, Merriman JH, Mertens S, Miley HS, Miller ML, Myslik J, Orrell JL, O'Shaughnessy C, Othman G, Overman NR, Perumpilly G, Pettus W, Phillips DG, Poon AWP, Pushkin K, Radford DC, Rager J, Reeves JH, Reine AL, Rielage K, Robertson RGH, Ronquest MC, Ruof NW, Schubert AG, Shanks B, Shirchenko M, Snavely KJ, Snyder N, Steele D, Suriano AM, Tedeschi D, Tornow W, Trimble JE, Varner RL, Vasilyev S, Vetter K, Vorren K, White BR, Wilkerson JF, Wiseman C, Xu W, Yakushev E, Yaver H, Young AR, Yu CH, Yumatov V, Zhitnikov I, Zhu BX, Zimmermann S. Search for Neutrinoless Double-β Decay in ^{76}Ge with the Majorana Demonstrator. PHYSICAL REVIEW LETTERS 2018; 120:132502. [PMID: 29694188 DOI: 10.1103/physrevlett.120.132502] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/09/2018] [Indexed: 06/08/2023]
Abstract
The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-β decay in ^{76}Ge. The Majorana Demonstrator comprises 44.1 kg of Ge detectors (29.7 kg enriched in ^{76}Ge) split between two modules contained in a low background shield at the Sanford Underground Research Facility in Lead, South Dakota. Here we present results from data taken during construction, commissioning, and the start of full operations. We achieve unprecedented energy resolution of 2.5 keV FWHM at Q_{ββ} and a very low background with no observed candidate events in 9.95 kg yr of enriched Ge exposure, resulting in a lower limit on the half-life of 1.9×10^{25} yr (90% C.L.). This result constrains the effective Majorana neutrino mass to below 240-520 meV, depending on the matrix elements used. In our experimental configuration with the lowest background, the background is 4.0_{-2.5}^{+3.1} counts/(FWHM t yr).
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Meents A, Wiedorn MO, Srajer V, Henning R, Sarrou I, Bergtholdt J, Barthelmess M, Reinke PYA, Dierksmeyer D, Tolstikova A, Schaible S, Messerschmidt M, Ogata CM, Kissick DJ, Taft MH, Manstein DJ, Lieske J, Oberthuer D, Fischetti RF, Chapman HN. Pink-beam serial crystallography. Nat Commun 2017; 8:1281. [PMID: 29097720 PMCID: PMC5668288 DOI: 10.1038/s41467-017-01417-3] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 09/14/2017] [Indexed: 02/02/2023] Open
Abstract
Serial X-ray crystallography allows macromolecular structure determination at both X-ray free electron lasers (XFELs) and, more recently, synchrotron sources. The time resolution for serial synchrotron crystallography experiments has been limited to millisecond timescales with monochromatic beams. The polychromatic, "pink", beam provides a more than two orders of magnitude increased photon flux and hence allows accessing much shorter timescales in diffraction experiments at synchrotron sources. Here we report the structure determination of two different protein samples by merging pink-beam diffraction patterns from many crystals, each collected with a single 100 ps X-ray pulse exposure per crystal using a setup optimized for very low scattering background. In contrast to experiments with monochromatic radiation, data from only 50 crystals were required to obtain complete datasets. The high quality of the diffraction data highlights the potential of this method for studying irreversible reactions at sub-microsecond timescales using high-brightness X-ray facilities.
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Fischetti RF, Martin-Garcia J, Zatsepin N, Stander N, Zhu L, Subramanian G, Nelson G, Coe J, Nagaratnam N, Roy-Chowdury S, Kissick D, Ishchenko A, Conrad C, Ketawala G, James D, Zook J, Ogata C, Venugopalan N, Xu S, Meents A, Srajer V, Henning R, Chapman H, Spence J, Weierstall U, Cherezov V, Fromme P, Liu W. Monochromatic and polychromatic serial crystallography at the Advanced Photon Source. Acta Crystallogr A Found Adv 2017. [DOI: 10.1107/s0108767317096404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Meents A, Wiedorn MO, Srajer V, Henning R, Sarrou I, Bergtholdt J, Barthelmess M, Reinke P, Dierksmeyer D, Tolstikova A, Schaible S, Messerschmidt M, Ogata CM, Kissick DJ, Taft M, Manstein D, Lieske J, Oberthuer D, Fischetti RF, Chapman HN. Low-background pink-beam serial crystallography. Acta Crystallogr A Found Adv 2017. [DOI: 10.1107/s0108767317096052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Abgrall N, Arnquist IJ, Avignone FT, Barabash AS, Bertrand FE, Bradley AW, Brudanin V, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Cuesta C, Detwiler JA, Dunagan C, Efremenko Y, Ejiri H, Elliott SR, Gilliss T, Giovanetti GK, Goett J, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CRS, Henning R, Hoppe EW, Howard S, Howe MA, Jasinski BR, Keeter KJ, Kidd MF, Konovalov SI, Kouzes RT, Lopez AM, MacMullin J, Martin RD, Massarczyk R, Meijer SJ, Mertens S, O'Shaughnessy C, Poon AWP, Radford DC, Rager J, Reine AL, Rielage K, Robertson RGH, Shanks B, Shirchenko M, Suriano AM, Tedeschi D, Trimble JE, Varner RL, Vasilyev S, Vetter K, Vorren K, White BR, Wilkerson JF, Wiseman C, Xu W, Yakushev E, Yu CH, Yumatov V, Zhitnikov I, Zhu BX. New Limits on Bosonic Dark Matter, Solar Axions, Pauli Exclusion Principle Violation, and Electron Decay from the Majorana Demonstrator. PHYSICAL REVIEW LETTERS 2017; 118:161801. [PMID: 28474933 DOI: 10.1103/physrevlett.118.161801] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Indexed: 06/07/2023]
Abstract
We present new limits on exotic keV-scale physics based on 478 kg d of Majorana Demonstrator commissioning data. Constraints at the 90% confidence level are derived on bosonic dark matter (DM) and solar axion couplings, Pauli exclusion principle violating (PEPV) decay, and electron decay using monoenergetic peak signal limits above our background. Our most stringent DM constraints are set for 11.8 keV mass particles, limiting g_{Ae}<4.5×10^{-13} for pseudoscalars and (α^{'}/α)<9.7×10^{-28} for vectors. We also report a 14.4 keV solar axion coupling limit of g_{AN}^{eff}×g_{Ae}<3.8×10^{-17}, a 1/2β^{2}<8.5×10^{-48} limit on the strength of PEPV electron transitions, and a lower limit on the electron lifetime of τ_{e}>1.2×10^{24} yr for e^{-}→ invisible.
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Cabauatan CR, Campana R, Niespodziana K, Reinisch C, Lundberg U, Meinke A, Henning R, Neubauer A, Valenta R. Heat-labile Escherichia coli toxin enhances the induction of allergen-specific IgG antibodies in epicutaneous patch vaccination. Allergy 2017; 72:164-168. [PMID: 27568860 PMCID: PMC5215485 DOI: 10.1111/all.13036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/26/2016] [Indexed: 11/27/2022]
Abstract
Epicutaneous allergen-specific immunotherapy (EPIT) is proposed as an alternative route for allergen-specific immunotherapy (AIT). The induction of allergen-specific blocking IgG antibodies represents an important mechanism underlying AIT, but has not been investigated for EPIT. Here, we compared the induction of allergen-specific blocking IgG in outbred guinea pigs which had been immunized with recombinant birch pollen allergen Bet v 1 using patch delivery system (PDS) with or without heat-labile toxin (LT) from Escherichia coli or subcutaneously with aluminum hydroxide (Alum)-adsorbed rBet v 1. Only subcutaneous immunization with Alum-adsorbed rBet v 1 and epicutaneous administration of rBet v 1 with PDS in combination with LT from E. coli induced allergen-specific IgG antibodies blocking allergic patients' IgE, but not immunization with rBet v 1 via PDS alone. Our results suggest that patch vaccination with rBet v 1 in combination with LT may be a promising strategy for allergen-specific immunotherapy against birch pollen allergy.
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Bertoni R, Lorenc M, Graber T, Henning R, Moffat K, Létard JF, Collet E. Cooperative elastic switching vs. laser heating in [Fe(phen)2(NCS)2] spin-crossover crystals excited by a laser pulse. CrystEngComm 2016; 18:7269-7275. [PMID: 28127256 PMCID: PMC5256688 DOI: 10.1039/c6ce00659k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Spin-crossover crystals show multi-step responses to femtosecond light excitation. The local molecular photo-switching from low to high spin states occurs on sub-picosecond timescale. It is followed by additional conversion due to elastic (ns) and thermal (μs) effects. In [Fe(phen)2(NCS)2] crystals discussed herein, the thermal switching can be made unobtrusive for the investigation of cooperative elastic switching. We evidence a cooperative transformation induced by lattice expansion through elastic coupling between molecules in the crystal, where up to 3 molecules are transformed per photon.
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Loether A, Adams BW, DiCharia A, Gao Y, Henning R, Walko DA, DeCamp MF. Pump-probe spectrometer for measuring x-ray induced strain. OPTICS LETTERS 2016; 41:1977-1980. [PMID: 27128053 PMCID: PMC5540162 DOI: 10.1364/ol.41.001977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A hard x-ray pump-probe spectrometer using a multi-crystal Bragg reflector is demonstrated at a third generation synchrotron source. This device derives both broadband pump and monochromatic probe pulses directly from a single intense, broadband x-ray pulse centered at 8.767 keV. We present a proof-of-concept experiment which directly measures x-ray induced crystalline lattice strain.
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Marino A, Buron-Le Cointe M, Lorenc M, Toupet L, Henning R, DiChiara AD, Moffat K, Bréfuel N, Collet E. Out-of-equilibrium dynamics of photoexcited spin-state concentration waves. Faraday Discuss 2015; 177:363-79. [PMID: 25627455 DOI: 10.1039/c4fd00164h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The spin crossover compound [FeIIH2L2-Me][PF6]2 presents a two-step phase transition. In the intermediate phase, a spin state concentration wave (SSCW) appears resulting from a symmetry breaking (cell doubling) associated with a long-range order of alternating high and low spin molecular states. By combining time-resolved optical and X-ray diffraction measurements on a single crystal, we study how such a system responds to femtosecond laser excitation and we follow in real time the erasing and rewriting of the SSCW.
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Accardo L, Aguilar M, Aisa D, Alpat B, Alvino A, Ambrosi G, Andeen K, Arruda L, Attig N, Azzarello P, Bachlechner A, Barao F, Barrau A, Barrin L, Bartoloni A, Basara L, Battarbee M, Battiston R, Bazo J, Becker U, Behlmann M, Beischer B, Berdugo J, Bertucci B, Bigongiari G, Bindi V, Bizzaglia S, Bizzarri M, Boella G, de Boer W, Bollweg K, Bonnivard V, Borgia B, Borsini S, Boschini MJ, Bourquin M, Burger J, Cadoux F, Cai XD, Capell M, Caroff S, Carosi G, Casaus J, Cascioli V, Castellini G, Cernuda I, Cerreta D, Cervelli F, Chae MJ, Chang YH, Chen AI, Chen H, Cheng GM, Chen HS, Cheng L, Chikanian A, Chou HY, Choumilov E, Choutko V, Chung CH, Cindolo F, Clark C, Clavero R, Coignet G, Consolandi C, Contin A, Corti C, Coste B, Cui Z, Dai M, Delgado C, Della Torre S, Demirköz MB, Derome L, Di Falco S, Di Masso L, Dimiccoli F, Díaz C, von Doetinchem P, Du WJ, Duranti M, D'Urso D, Eline A, Eppling FJ, Eronen T, Fan YY, Farnesini L, Feng J, Fiandrini E, Fiasson A, Finch E, Fisher P, Galaktionov Y, Gallucci G, García B, García-López R, Gast H, Gebauer I, Gervasi M, Ghelfi A, Gillard W, Giovacchini F, Goglov P, Gong J, Goy C, Grabski V, Grandi D, Graziani M, Guandalini C, Guerri I, Guo KH, Haas D, Habiby M, Haino S, Han KC, He ZH, Heil M, Henning R, Hoffman J, Hsieh TH, Huang ZC, Huh C, Incagli M, Ionica M, Jang WY, Jinchi H, Kanishev K, Kim GN, Kim KS, Kirn T, Kossakowski R, Kounina O, Kounine A, Koutsenko V, Krafczyk MS, Kunz S, La Vacca G, Laudi E, Laurenti G, Lazzizzera I, Lebedev A, Lee HT, Lee SC, Leluc C, Levi G, Li HL, Li JQ, Li Q, Li Q, Li TX, Li W, Li Y, Li ZH, Li ZY, Lim S, Lin CH, Lipari P, Lippert T, Liu D, Liu H, Lolli M, Lomtadze T, Lu MJ, Lu YS, Luebelsmeyer K, Luo F, Luo JZ, Lv SS, Majka R, Malinin A, Mañá C, Marín J, Martin T, Martínez G, Masi N, Massera F, Maurin D, Menchaca-Rocha A, Meng Q, Mo DC, Monreal B, Morescalchi L, Mott P, Müller M, Ni JQ, Nikonov N, Nozzoli F, Nunes P, Obermeier A, Oliva A, Orcinha M, Palmonari F, Palomares C, Paniccia M, Papi A, Pauluzzi M, Pedreschi E, Pensotti S, Pereira R, Pilastrini R, Pilo F, Piluso A, Pizzolotto C, Plyaskin V, Pohl M, Poireau V, Postaci E, Putze A, Quadrani L, Qi XM, Rancoita PG, Rapin D, Ricol JS, Rodríguez I, Rosier-Lees S, Rossi L, Rozhkov A, Rozza D, Rybka G, Sagdeev R, Sandweiss J, Saouter P, Sbarra C, Schael S, Schmidt SM, Schuckardt D, Schulz von Dratzig A, Schwering G, Scolieri G, Seo ES, Shan BS, Shan YH, Shi JY, Shi XY, Shi YM, Siedenburg T, Son D, Spada F, Spinella F, Sun W, Sun WH, Tacconi M, Tang CP, Tang XW, Tang ZC, Tao L, Tescaro D, Ting SCC, Ting SM, Tomassetti N, Torsti J, Türkoğlu C, Urban T, Vagelli V, Valente E, Vannini C, Valtonen E, Vaurynovich S, Vecchi M, Velasco M, Vialle JP, Vitale V, Volpini G, Wang LQ, Wang QL, Wang RS, Wang X, Wang ZX, Weng ZL, Whitman K, Wienkenhöver J, Wu H, Wu KY, Xia X, Xie M, Xie S, Xiong RQ, Xin GM, Xu NS, Xu W, Yan Q, Yang J, Yang M, Ye QH, Yi H, Yu YJ, Yu ZQ, Zeissler S, Zhang JH, Zhang MT, Zhang XB, Zhang Z, Zheng ZM, Zhou F, Zhuang HL, Zhukov V, Zichichi A, Zimmermann N, Zuccon P, Zurbach C. High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station. PHYSICAL REVIEW LETTERS 2014; 113:121101. [PMID: 25279616 DOI: 10.1103/physrevlett.113.121101] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Indexed: 06/03/2023]
Abstract
A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200 GeV the positron fraction no longer exhibits an increase with energy.
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