相关论文: Relic gravitons and high-frequency detectors
High-frequency gravitational waves (HFGWs) carry a wealth of information on the early Universe with a tiny comoving horizon and astronomical objects of small scale but with dense energy. We demonstrate that the nearby planets, such as Earth…
A key test of the isotropy of the Universe on large scales consists in comparing the dipole in the Cosmic Microwave Background (CMB) temperature with the dipole in the distribution of sources at low redshift. Current analyses find a dipole…
We examine the spectrum of gravitational radiation emitted by a network of cosmic strings, with emphasis on the observational constraints and the opportunities for detection. The analysis improves over past work, as we use a…
The direct detection of gravitational waves (GWs) of frequencies above MHz has recently received considerable attention. In this work we present a precise study of the reach of a cubic cavity resonator to GWs in the microwave range, using…
The next generation of gravitational wave detectors holds out the prospect of detecting a stochastic gravitational background generated in the very early universe. In this article, we review the various cosmological processes which can lead…
We perform a search for gravitational wave bursts using data from the second science run of the LIGO detectors, using a method based on a wavelet time-frequency decomposition. This search is sensitive to bursts of duration much less than a…
A GHz maser beam with Gaussian-type distribution passing through a homogenous static magnetic field can be used to detect gravitational waves (GWs) with the same frequency. The presence of GWs will perturb the electromagnetic (EM) fields,…
We propose to uncover the signature of a stringy era in the primordial Universe by searching for a prominent peak in the relic graviton spectrum. This feature, which in our specific model terminates an $\omega^3$ increase and initiates an…
Gravitational wave (GW) detection in space is aimed at low frequency band (100 nHz - 100 mHz) and middle frequency band (100 mHz - 10 Hz). The science goals are the detection of GWs from (i) Supermassive Black Holes; (ii) Extreme-Mass-Ratio…
Primordial magnetic fields (PMFs) can source gravitational wave background (GWB). In this paper, we investigate the possible constraints on small-scale PMF considering the ongoing and forthcoming direct detection observations of GWB. In…
Stationary processes do not accurately describe the diffuse backgrounds of relic gravitons whose correlations are homogeneous in space (i.e. only dependent upon the distance between the two spatial locations) but not in time. The symmetries…
Searches for a stochastic gravitational-wave background (SGWB) using terrestrial detectors typically involve cross-correlating data from pairs of detectors. The sensitivity of such cross-correlation analyses depends, among other things, on…
The sensitivity achievable by a pair of VIRGO detectors to stochastic and isotropic gravitational wave backgrounds produced in pre-big-bang models is discussed in view of the development of a second VIRGO interferometer. We describe a…
We investigate the impact of the post-inflationary thermal histories on the cosmic graviton spectrum caused by the inflationary variation of their refractive index. Depending on the frequency band, the spectral energy distribution can be…
In this work, we present the first experimental upper limits on the presence of stochastic ultra-high-frequency gravitational waves. We exclude gravitational waves in the frequency bands from $(2.7 - 14)\times10^{14}~$Hz and $(5 -…
We explore the possibility of detecting the excess of the cosmic radio background (CRB) toward galaxy clusters due to its Compton scattering by electrons of the hot intergalactic gas. When mapping the background fluctuations at frequencies…
We propose a tunable resonant sensor to detect gravitational waves in the frequency range of 50-300 kHz using optically trapped and cooled dielectric microspheres or micro-discs. The technique we describe can exceed the sensitivity of…
This is an expanded version of my talk given at the international conference "Zeldovich-90". I start with a brief recollection of interactions with Zeldovich in the context of the study of relic gravitational waves. I then summarise the…
Gravitational waves have predominantly been detected using interferometric techniques, with standard approaches limited to 10 kHz and with modern advancements extending this bound to 300 kHz. To explore the largely uncharted…
Ultra-high frequency gravitational waves in the MHz to THz regime promise a unique possibility to probe the very early universe, particle physics at very high energies and exotic astrophysical objects - but achieving the sensitivity…