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The Origin of the Flat Rotation Curves in Spiral Galaxies: The Hidden Roles of Glitching SMDEOs and Emission of Gravitational Waves
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作者 Ahmad A. Hujeirat Peter Berczik 《Journal of Modern Physics》 2024年第10期1523-1542,共20页
Supermassive DEOs (SMDEOs) are cosmologically evolved objects made of irreducible incompressible supranuclear dense superfluids: The state we consider to govern the matter inside the cores of massive neutron stars. Th... Supermassive DEOs (SMDEOs) are cosmologically evolved objects made of irreducible incompressible supranuclear dense superfluids: The state we consider to govern the matter inside the cores of massive neutron stars. These cores are practically trapped in false vacua, rendering their detection by outside observers impossible. Based on massive parallel computations and theoretical investigations, we show that SMDEOs at the centres of spiral galaxies that are surrounded by massive rotating torii of normal matter may serve as powerful sources for gravitational waves carrying away roughly 1042 erg/s. Due to the extensive cooling by GWs, the SMDEO-Torus systems undergo glitching, through which both rotational and gravitational energies are abruptly ejected into the ambient media, during which the topologies of the embedding spacetimes change from curved into flatter ones, thereby triggering a burst gravitational energy of order 1059 erg. Also, the effects of glitches found to alter the force balance of objects in the Lagrangian-L1 region between the central SMDEO-Torus system and the bulge, enforcing the enclosed objects to develop violent motions, that may explain the origin of the rotational curve irregularities observed in the innermost part of spiral galaxies. Our study shows that the generated GWs at the centres of galaxies, which traverse billions of objects during their outward propagations throughout the entire galaxy, lose energy due to repeatedly squeezing and stretching the objects. Here, we find that these interactions may serve as damping processes that give rise to the formation of collective forces f∝m(r)/r, that point outward, endowing the objects with the observed flat rotation curves. Our approach predicts a correlation between the baryonic mass and the rotation velocities in galaxies, which is in line with the Tully-Fisher relation. The here-presented self-consistent approach explains nicely the observed rotation curves without invoking dark matter or modifying Newtonian gravitation in the low-field approximation. 展开更多
关键词 General Relativity: Black Holes Neutron Stars Quantum Fields: QCD Condensed Matter INCOMPRESSIBILITY SUPERFLUIDITY Cosmology: Galaxy Formation Spiral Galaxies Dark Matter Rotation Curves
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Forecast of Observing Time Delay of Strongly Lensed Quasars with the Muztagh-Ata 1.93m Telescope
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作者 Shanhao Zhu Yiping Shu +8 位作者 Haibo Yuan Jian-Ning Fu Jian Gao Jianghua Wu Xiangtao He Kai Liao Guoliang Li Xinzhong Er Bin Hu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第3期1-15,共15页
As a completely independent method,the measurement of time delay of strongly lensed quasars(TDSL)are crucial to resolve the Hubble tension.Extensive monitoring is required but so far limited to a small sample of stron... As a completely independent method,the measurement of time delay of strongly lensed quasars(TDSL)are crucial to resolve the Hubble tension.Extensive monitoring is required but so far limited to a small sample of strongly lensed quasars.Together with several partner institutes,Beijing Normal University is constructing a 1.93 m reflector telescope at the Muztagh-Ata site in west China,which has the world class observing conditions with median seeing of 082 and median sky brightness of 21.74 mag arcsec-2 in V-band during the dark time.The telescope will be equipped with both a three-channel imager/photometer which covers 3500–11,000?wavelength band,and a low-medium resolution(λ/δλ=500/2000/7500)spectrograph.In this paper,we investigate the capability of the Muztagh-Ata 1.93 m telescope in measuring time delays of strongly lensed quasars.We generate mock strongly lensed quasar systems and light curves with microlensing effects based on five known strongly lensed quasars,i.e.,RX J1131-1231,HE 0435-1223,PG 1115+080,WFI 2033-4723 and SDSS 1206+4332.In particular,RX J1131-1231 is generated based on the lens modeling results of Suyu et al.Due to the lack of enough information,the other four systems are calculated by a simple analytical approximation.According to simulations,for RX J1131-like systems(wide variation in time delay between images)the TDSL measurement can be achieved with the precision aboutΔt=0.5 day with four seasons campaign length and 1 day cadence.This accuracy is comparable to the up-coming TDCOSMO project.And it would be better when the campaign length keeps longer and with high cadence.As a result,the capability of the Muztagh-Ata 1.93 m telescope allows it to join the network of TDSL observatories.It will enrich the database for strongly lensed quasar observations and make more precise measurements of time delays,especially considering the unique coordinate of the site. 展开更多
关键词 equipped TOGETHER PRECISE
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Self-assembled thermosensitive luminescent nanoparticles with peptide-Au conjugates for cellular imaging and drug delivery 被引量:3
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作者 Xiaoyuan Zhang Wei Liu +5 位作者 Haixia Wang Xinne Zhao Zhenfang Zhang Gerd Ulrich Nienhaus Li Shang Zhiqiang Su 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第3期859-864,共6页
A facile and efficient strategy has been developed to fabricate a multifunctional,theranostic anticancer drug delivery platform featuring active targeting,controlled drug release and fluorescence imaging for real-time... A facile and efficient strategy has been developed to fabricate a multifunctional,theranostic anticancer drug delivery platform featuring active targeting,controlled drug release and fluorescence imaging for real-time control of delivery.To this end,thermo sensitive poly(N-isopropyl acrylamide)(PNIPAM)nanospheres are decorated with peptide-Au cluster conjugates as a smart nanomedicine platform.A sophisticated trifunctional peptide is designed to release the anticancer drug doxorubicin(DOX),target cells and reduce Au^3+ions to form luminescent Au cluste rs.Importantly,the peptide-Au cluster moieties are attached to the PNIPAM nanospheres via amide bonds rather than noncovalent interactions,significantly improving their stability in biological medium and drug release efficiency.The in vitro experiments showed that DOX was released in an efficient and controlled manner under physiological conditions. 展开更多
关键词 Peptide-Au BIOCONJUGATES PNIPAM NANOPARTICLES Fluorescence Drug delivery Cell imaging
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Flux quantum tunneling effect and its influence on the experimental critical current density
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作者 闻海虎 赵忠贤 GriessenR. 《Science China Mathematics》 SCIE 1995年第6期717-723,共7页
By using magnetic sweeping method, the temperature and magnetic field dependencies of the experimental current density and the normalized relaxation rate have been obtained. The true critical current density correspon... By using magnetic sweeping method, the temperature and magnetic field dependencies of the experimental current density and the normalized relaxation rate have been obtained. The true critical current density corresponding to the zero activation energy has been carried out based on the collective-pinning and the thermally-activated flux motion models, and therefore the influences of the quantum tunneling effect and the thermal activation effect on the experimental critical current density are distinguished. It is found that, with temperature lower than 10 K, the relaxation rate will not drop to zero when T approaches zero K because of the occurrence of the flux quantum tunneling. This additional flux motion further reduces the experimental critical current density j making it saturated with lowering temperature. 展开更多
关键词 FLUX quantum TUNNELING effect thermally-activated FLUX motion collective-pinning CRITICAL current density.
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磁通量子隧道效应及其对实验临界电流的影响
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作者 闻海虎 赵忠贤 R.Griessen 《中国科学(A辑)》 CSCD 1995年第6期602-607,共6页
采用磁扫描测量方法,在YBCO(123和124)薄膜上获得了实验临界电流和磁弛豫率随温度及磁场的依赖关系,借助于集体钉扎和热激活磁通运动模型,求出了真实临界电流(即对应于激活能为0的电流),从而区分开量子磁通隧道效应和热激活磁通运动对... 采用磁扫描测量方法,在YBCO(123和124)薄膜上获得了实验临界电流和磁弛豫率随温度及磁场的依赖关系,借助于集体钉扎和热激活磁通运动模型,求出了真实临界电流(即对应于激活能为0的电流),从而区分开量子磁通隧道效应和热激活磁通运动对实验临界电流的影响,发现当温度(T)约低于10K时,由于磁通量子隧道效应的存在使得磁弛豫率不再随温度的下降外延至零,这种额外的磁通运动进一步降低了实验临界电流值,使其在低温下随温度降低而趋于饱和。 展开更多
关键词 磁通 量子隧道效应 磁通运动 临界电流 超导体
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