This study presents signatures of seismo-ionospheric perturbations possibly related to the 14 July 2019 M_(w)7.2 Laiwui earthquake,detected by a cross-validation analysis of total electron content(TEC)data of the glob...This study presents signatures of seismo-ionospheric perturbations possibly related to the 14 July 2019 M_(w)7.2 Laiwui earthquake,detected by a cross-validation analysis of total electron content(TEC)data of the global ionospheric map(GIM)from GPS and plasma parameter data recorded by the China Seismo-Electromagnetic Satellite(CSES).After separating pre-seismic ionospheric phenomena from the ionospheric disturbances due to the magnetospheric and solar activities,we have identified three positive temporal anomalies,around the epicenter,at 1 day,3 days and 8 days before the earthquake(14 July 2019),along with a negative anomaly 6 days after the earthquake.These results agree well with the TEC spatial variations in latitude-longitude-time(LLT)maps.To confirm these anomalies further,we employed the moving mean method(MMM)to analyze ionospheric plasma parameters(electron,O^(+) and He^(+) densities)recorded by the Langmuir probe(LAP)and Plasma Analyzer Package(PAP)onboard the CSES.The analysis detected on,on Day Two,Day Four,and Day Seven before the earthquake,remarkable enhancements along the orbits around when in proximity to the epicenter.To make the investigations still more convincing,we compared the orbits on which anomalous readings were recorded to their corresponding four nearest revisiting orbits;the comparison did indeed indicate the existence of plasma parameter anomalies that appear to be associated with the Laiwui earthquake.All these results ilustrate that the unusual ionospheric perturbations detected through GPS and CSES data are possibly associated with the M_(w)7.2 Laiwui earthquake,which suggests that at least some earthquakes may be predicted by alertness to pre-seismic ionospheric anomalies over regions known to be at seismic risk.This case study also contributes additional information of value to our understanding of lithosphere-atmosphere-ionosphere coupling.展开更多
CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle envi...CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle environment, for studying the seismo-associated disturbances in the ionosphere-magnetosphere transition zone. The anthropogenic and electromagnetic noise,as well as the natural non-seismic electromagnetic emissions is mainly due to tropospheric activity. In particular, the mission aims to confirming the existence of possible temporal correlations between the occurrence of earthquakes for medium and strong magnitude and the observation in space of electromagnetic perturbations, plasma variations and precipitation of bursts with highenergy charged particles from the inner Van Allen belt. In this framework, the high energy particle detector(HEPD) of the CSES mission has been developed by the Italian LIMADOU Collaboration. HEPD is an advanced detector based on a tower of scintillators and a silicon tracker that provides good energy and angular resolution and a wide angular acceptance, for electrons of 3–100 Me V, protons of 30–200 Me V and light nuclei up to the oxygen. CSES satellite has been launched on February 2^(nd), 2018 from the Jiuquan Satellite Launch Center(China).展开更多
Single-photon entanglement is a peculiar type of entanglement in which two or more degrees of freedom of a single photon are correlated quantum-mechanically. Here, we demonstrate a photonic integrated chip able to gen...Single-photon entanglement is a peculiar type of entanglement in which two or more degrees of freedom of a single photon are correlated quantum-mechanically. Here, we demonstrate a photonic integrated chip able to generate and manipulate single-photon path-entangled states, using a commercial red LED as light source.A Bell test, in the Clauser, Horne, Shimony, and Holt(CHSH) form, is performed to confirm the presence of entanglement, resulting in a maximum value of the CHSH correlation parameter equal to 2.605 ± 0.004.This allows us to use it as an integrated semi-device independent quantum random number generator able to produce certified random numbers. The certification scheme is based on a Bell’s inequality violation and on a partial characterization of the experimental setup, without the need of introducing any further assumptions either on the input state or on the particular form of the measurement observables. In the end a min-entropy of 33% is demonstrated.展开更多
In this paper we present the enhanced X-ray Timing and Polarimetry mission—eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The m...In this paper we present the enhanced X-ray Timing and Polarimetry mission—eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The mission aims at determining the equation of state of matter at supra-nuclear density, measuring effects of QED, and understanding the dynamics of matter in strong-field gravity. In addition to investigating fundamental physics, eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects. In particular, its wide field monitoring capabilities will be highly instrumental to detect the electro-magnetic counterparts of gravitational wave sources.The paper provides a detailed description of:(1) the technological and technical aspects, and the expected performance of the instruments of the scientific payload;(2) the elements and functions of the mission, from the spacecraft to the ground segment.展开更多
基金a project funded by China National Space Administration (CNSA)China Earthquake Administration (CEA)+1 种基金supported by the National Natural Science Foundation of China (Grant No. 42004137)the Natural Science Foundation of Sichuan Province of China (Grant No. 22NSFSC3946)
文摘This study presents signatures of seismo-ionospheric perturbations possibly related to the 14 July 2019 M_(w)7.2 Laiwui earthquake,detected by a cross-validation analysis of total electron content(TEC)data of the global ionospheric map(GIM)from GPS and plasma parameter data recorded by the China Seismo-Electromagnetic Satellite(CSES).After separating pre-seismic ionospheric phenomena from the ionospheric disturbances due to the magnetospheric and solar activities,we have identified three positive temporal anomalies,around the epicenter,at 1 day,3 days and 8 days before the earthquake(14 July 2019),along with a negative anomaly 6 days after the earthquake.These results agree well with the TEC spatial variations in latitude-longitude-time(LLT)maps.To confirm these anomalies further,we employed the moving mean method(MMM)to analyze ionospheric plasma parameters(electron,O^(+) and He^(+) densities)recorded by the Langmuir probe(LAP)and Plasma Analyzer Package(PAP)onboard the CSES.The analysis detected on,on Day Two,Day Four,and Day Seven before the earthquake,remarkable enhancements along the orbits around when in proximity to the epicenter.To make the investigations still more convincing,we compared the orbits on which anomalous readings were recorded to their corresponding four nearest revisiting orbits;the comparison did indeed indicate the existence of plasma parameter anomalies that appear to be associated with the Laiwui earthquake.All these results ilustrate that the unusual ionospheric perturbations detected through GPS and CSES data are possibly associated with the M_(w)7.2 Laiwui earthquake,which suggests that at least some earthquakes may be predicted by alertness to pre-seismic ionospheric anomalies over regions known to be at seismic risk.This case study also contributes additional information of value to our understanding of lithosphere-atmosphere-ionosphere coupling.
基金supported by the Italian Space Agency in the framework of the“Accordo Attuativo n.2016-16-H0 Progetto Limadou Fase E/Scienza”(CUP F12F1600011005)
文摘CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle environment, for studying the seismo-associated disturbances in the ionosphere-magnetosphere transition zone. The anthropogenic and electromagnetic noise,as well as the natural non-seismic electromagnetic emissions is mainly due to tropospheric activity. In particular, the mission aims to confirming the existence of possible temporal correlations between the occurrence of earthquakes for medium and strong magnitude and the observation in space of electromagnetic perturbations, plasma variations and precipitation of bursts with highenergy charged particles from the inner Van Allen belt. In this framework, the high energy particle detector(HEPD) of the CSES mission has been developed by the Italian LIMADOU Collaboration. HEPD is an advanced detector based on a tower of scintillators and a silicon tracker that provides good energy and angular resolution and a wide angular acceptance, for electrons of 3–100 Me V, protons of 30–200 Me V and light nuclei up to the oxygen. CSES satellite has been launched on February 2^(nd), 2018 from the Jiuquan Satellite Launch Center(China).
文摘Single-photon entanglement is a peculiar type of entanglement in which two or more degrees of freedom of a single photon are correlated quantum-mechanically. Here, we demonstrate a photonic integrated chip able to generate and manipulate single-photon path-entangled states, using a commercial red LED as light source.A Bell test, in the Clauser, Horne, Shimony, and Holt(CHSH) form, is performed to confirm the presence of entanglement, resulting in a maximum value of the CHSH correlation parameter equal to 2.605 ± 0.004.This allows us to use it as an integrated semi-device independent quantum random number generator able to produce certified random numbers. The certification scheme is based on a Bell’s inequality violation and on a partial characterization of the experimental setup, without the need of introducing any further assumptions either on the input state or on the particular form of the measurement observables. In the end a min-entropy of 33% is demonstrated.
基金support of the Chinese Academy of Sciences through the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA15020100)support by ASI, under the dedicated eXTP agreements and agreement ASI-INAF (Grant No. 2017-14-H.O.)+3 种基金by INAF and INFN under project REDSOXsupport from the Deutsche Zentrum für Luft- und Raumfahrt, the German Aerospce Center (DLR)support of Science Centre (Grant No. 2013/10/M/ST9/00729)support from MINECO (Grant No. ESP2017-82674-R) and FEDER funds
文摘In this paper we present the enhanced X-ray Timing and Polarimetry mission—eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The mission aims at determining the equation of state of matter at supra-nuclear density, measuring effects of QED, and understanding the dynamics of matter in strong-field gravity. In addition to investigating fundamental physics, eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects. In particular, its wide field monitoring capabilities will be highly instrumental to detect the electro-magnetic counterparts of gravitational wave sources.The paper provides a detailed description of:(1) the technological and technical aspects, and the expected performance of the instruments of the scientific payload;(2) the elements and functions of the mission, from the spacecraft to the ground segment.
