The high frequency gravitational waves (around lOS-lO12 Hz) could interact with a specially designed electro- magnetic resonance system. It is found that the power of transverse perturbative photon flux (PPF) of a...The high frequency gravitational waves (around lOS-lO12 Hz) could interact with a specially designed electro- magnetic resonance system. It is found that the power of transverse perturbative photon flux (PPF) of an electromagnetic resonance system can be improved significantly by virtue of an astigmatic Caussian beam. Cor- respondingly the signal-to-noise ratio (SNR) would also be improved. When the eccentric ratio of waist satisfying w0x : w0y 〉 1, the peak value of signal photon flux could be raised by 2-4 times with typical systematic parameters, while the background photon flux would be depressed. Therefore, the ratio of transverse PPF to background photon flux (i.e., SNR) can be further improved 3-8 times with dimensionless amplitude of relic gravitational wave ht = 10-36.展开更多
This paper discusses the basic categories of noise in detecting high frequency gravitational waves in the microwave band (-0.1-10GHz), which contain shot noise from the laser and the thermal radiation photons, therm...This paper discusses the basic categories of noise in detecting high frequency gravitational waves in the microwave band (-0.1-10GHz), which contain shot noise from the laser and the thermal radiation photons, thermal noise from statistical fluctuation of the thermal photons and fluctuation of the temperature, radiation press noise on the fractal membrane, the noise caused by the scattering of the Gaussian Beam (GB) in the detecting tube and noise in the microwave radiometers. The analysis shows that a reasonable signal-to-noise ratio may be achieved for a detecting device with the fixed power of GB (105 W), only when the temperature of the environment is no more than T=I K, and the optimal length of the microwave radiometers is about 0.3 m.展开更多
The power spectrum of primordial tensor perturbations Pt increases rapidly in the high frequency region if the spectral index nt 〉 0. It is shown that the amplitude of relic gravitational waves ht (5×109 Hz) v...The power spectrum of primordial tensor perturbations Pt increases rapidly in the high frequency region if the spectral index nt 〉 0. It is shown that the amplitude of relic gravitational waves ht (5×109 Hz) varies from 10-36 to 10-25 while rtt varies from -6.25 × 10-3 to 0.87. A high frequency gravitational wave detector proposed by F,-Y, Li detects gravitational waves through observing the perturbed photon flux that is generated by interaction between relic gravitational waves and electromagnetic field. It is shown that the perturbative photon flux N1x (5 × 109 Hz) varies from 1.40× 10-4 s-i to 2.85× 107 s-i while nt varies from -6.25 ×10-3 to 0.87, Correspondingly, the ratio of the transverse perturbative photon flux N1x to the background photon flux varies from 10-28 to 10-16.展开更多
Extremely powerful astrophysical electromagnetic(EM) systems could be possible sources of highfrequency gravitational waves(HFGWs). Here, based on properties of magnetars and gamma-ray bursts(GRBs), we address ...Extremely powerful astrophysical electromagnetic(EM) systems could be possible sources of highfrequency gravitational waves(HFGWs). Here, based on properties of magnetars and gamma-ray bursts(GRBs), we address "Gamma-HFGWs"(with very high-frequency around 1020 Hz) caused by ultra-strong EM radiation(in the radiation-dominated phase of GRB fireballs) interacting with super-high magnetar surface magnetic fields(~1011 T).By certain parameters of distance and power, the Gamma-HFGWs would have far field energy density ?gw around10-6, and they would cause perturbed signal EM waves of~10-20 W/m2 in a proposed HFGW detection system based on the EM response to GWs. Specially, Gamma-HFGWs would possess distinctive envelopes with characteristic shapes depending on the particular structures of surface magnetic fields of magnetars, which could be exclusive features helpful to distinguish them from background noise. Results obtained suggest that magnetars could be involved in possible astrophysical EM sources of GWs in the very high-frequency band, and Gamma-HFGWs could be potential targets for observations in the future.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11205254 and 61501069the Fundamental Research Funds for the Central Universities under Grant No 106112016CDJXY300002
文摘The high frequency gravitational waves (around lOS-lO12 Hz) could interact with a specially designed electro- magnetic resonance system. It is found that the power of transverse perturbative photon flux (PPF) of an electromagnetic resonance system can be improved significantly by virtue of an astigmatic Caussian beam. Cor- respondingly the signal-to-noise ratio (SNR) would also be improved. When the eccentric ratio of waist satisfying w0x : w0y 〉 1, the peak value of signal photon flux could be raised by 2-4 times with typical systematic parameters, while the background photon flux would be depressed. Therefore, the ratio of transverse PPF to background photon flux (i.e., SNR) can be further improved 3-8 times with dimensionless amplitude of relic gravitational wave ht = 10-36.
基金supported by the National Basic Research Program of China (Grant No 2003CB716300)the National Natural Science Foundation of China (Grant No 10575140)CAEP Foundation (Grant Nos 2008 T0401 and 2008 T0402)
文摘This paper discusses the basic categories of noise in detecting high frequency gravitational waves in the microwave band (-0.1-10GHz), which contain shot noise from the laser and the thermal radiation photons, thermal noise from statistical fluctuation of the thermal photons and fluctuation of the temperature, radiation press noise on the fractal membrane, the noise caused by the scattering of the Gaussian Beam (GB) in the detecting tube and noise in the microwave radiometers. The analysis shows that a reasonable signal-to-noise ratio may be achieved for a detecting device with the fixed power of GB (105 W), only when the temperature of the environment is no more than T=I K, and the optimal length of the microwave radiometers is about 0.3 m.
基金Supported by National Natural Science Foundation of China(11305181,11322545,11335012)Open Project Program of State Key Laboratory of Theoretical Physics,Institute of Theoretical Physics,Chinese Academy of Sciences,China(Y5KF181CJ1)
文摘The power spectrum of primordial tensor perturbations Pt increases rapidly in the high frequency region if the spectral index nt 〉 0. It is shown that the amplitude of relic gravitational waves ht (5×109 Hz) varies from 10-36 to 10-25 while rtt varies from -6.25 × 10-3 to 0.87. A high frequency gravitational wave detector proposed by F,-Y, Li detects gravitational waves through observing the perturbed photon flux that is generated by interaction between relic gravitational waves and electromagnetic field. It is shown that the perturbative photon flux N1x (5 × 109 Hz) varies from 1.40× 10-4 s-i to 2.85× 107 s-i while nt varies from -6.25 ×10-3 to 0.87, Correspondingly, the ratio of the transverse perturbative photon flux N1x to the background photon flux varies from 10-28 to 10-16.
基金Supported by National Natural Science Foundation of China(11605015,11375279,11205254,11647307)the Fundamental Research Funds for the Central Universities(106112017CDJXY300003,106112017CDJXFLX0014)
文摘Extremely powerful astrophysical electromagnetic(EM) systems could be possible sources of highfrequency gravitational waves(HFGWs). Here, based on properties of magnetars and gamma-ray bursts(GRBs), we address "Gamma-HFGWs"(with very high-frequency around 1020 Hz) caused by ultra-strong EM radiation(in the radiation-dominated phase of GRB fireballs) interacting with super-high magnetar surface magnetic fields(~1011 T).By certain parameters of distance and power, the Gamma-HFGWs would have far field energy density ?gw around10-6, and they would cause perturbed signal EM waves of~10-20 W/m2 in a proposed HFGW detection system based on the EM response to GWs. Specially, Gamma-HFGWs would possess distinctive envelopes with characteristic shapes depending on the particular structures of surface magnetic fields of magnetars, which could be exclusive features helpful to distinguish them from background noise. Results obtained suggest that magnetars could be involved in possible astrophysical EM sources of GWs in the very high-frequency band, and Gamma-HFGWs could be potential targets for observations in the future.