Présidents de session
Dark and Primordial Universe & Gravitational Waves
- Masaki ANDO (University of Tokyo) (University of Tokyo)
KAGRA operates at cryogenic temperature, therefore uses sapphire substrates as its test-masses. Next generation of gravitational wave detectors will also use crystalline substrates, possibly sapphire or silicon. All these materials are birefringent which can spoil both the sensitivity and duty-cycle of the detectors and therefore substrates with lowest possible birefringence are...
Fast Radio Bursts (FRBs) are one of the super-energetic radio pulsed signals with a short (< 1 sec) time duration. In recent years, numerous theoretical explanations for the origin of FRBs have been proposed. However, even with exotic physics, models have been unable to universally explain the properties of these events, such as peak flux and pulse width. In this study, we present a novel...
KAGRA is often referred as a 2.5-generation gravitational wave detector as it operates underground with test-masses at cryogenic temperature; features that will be implemented in future gravitational waves detectors. One of the constraints of operating at cryogenic temperature is that it requires the use crystalline test-masses. KAGRA test-masses substrates are therefore 22kg sapphire crystal....
The 2nd generation gravitational wave detectors network, including LIGO, Virgo, and KAGRA, ushered the era of gravitational wave (GW) astronomy, detecting more than 90 GW signals in the last years from the merging of binary compact objects. They are expected to start their fourth observation run (O4) in May this year, with improved sensitivity. The main limitation to the sensitivity comes from...
With the primary goal of direct dark matter search, the operation of the XENONnT experiment is ongoing.
The experiment, operated at the Laboratori Nazionali del Gran Sasso in Italy, uses a two-phase xenon time projection chamber with 6 tons of liquid xenon (8.6 tons in total).
I will present low-background techniques and the current status of XENONnT experiment.
Weakly Interacting Massive Particles(WIMPs) are most promising candidate of Dark Matter and annihilation of WIMPs could produce high-energy electrons.
In the presence of magnetic field, these high energy electrons emit synchrotron radiation.
Dwarf spheroidal galaxies (dSphs) are known to be Dark Matter dominated and low background object. Therefore dSphs are appealing candidates of indirect...
The Belle II experiment at the SuperKEKB collider has a unique sensitivity to a broad class of models that postulate the existence of dark matter particles with MeV—GeV masses. This talk presents recent world-leading physics results from Belle II searches for long-lived scalar particles and Z’ decays; as well as the near-term prospects for other dark-sector searches.
We present the latest ATLAS and CMS probes for new physics in searches for Dark Matter (DM) and Beyond the Standard Model (BSM) Higgs bosons at the Large Hadron Collider (LHC). The existence of dark matter, which constitutes a large majority of the matter in the Universe, is well established through various astrophysical observations. However, its nature is still unknown. Models predicting...
Exploration of black holes across the cosmic history not only has astrophysical values, but also represents key steps toward better understanding of putative primordial black holes, sources of gravitational waves, and other topics belonging to fundamental physics. We present the first statistical investigation of the black hole properties of low-luminosity quasars in the early cosmic epoch....
A model of an extended manifold for the Dirac spinor field is considered. Two Lagrangians related by CPTM (charge-parity-time-mass) symmetry are constructed for a pair of the Dirac spinor fields with each spinor field defined in a separate manifold. An interaction between the matter fields in the manifolds is introduced through gravity. A fermionic effective action of the general system is...
The long-standing Hubble constant (H0) tension is the discrepancy of more than 4σ between the local measurement of H0 through the Cepheids and Supernovae Ia (SNe Ia) and the cosmological value of H0 obtained with the Planck measurement of the Cosmic Microwave Background radiation. To investigate this tension, we performed an estimation of H0 in the standard ΛCDM and the w0waCDM models through...
The primordial B modes signal in the CMB is very faint and polluted by other polarised astrophysical signals. The future and present experiments that aim at constraining the tensor to scalar ratio are limited by the efficiency with which they are able to remove this contaminating signal. Furthermore, exquisite knowledge of the instrument is necessary to understand possible systematic effects...
Simons Array is one of experiments that are observing the cosmic microwave background to proof the existence of the primordial gravitational wave and inflation. Currently, the data taking of the first telescope and the deployment of the second telescope on Atacama Desert in Chile is proceeded on parallel.
In this presentation, the status of the Simons Array experiment will be reported...
The purpose of this research is to study cosmological effects of the coupling between dark energy and dark matter through the general conformal transformations in which the coefficient of conformal depends on both scalar field and its kinetic term. Using dynamical analysis, the influence of general conformal coupling on the evolution of background universe is investigated. We found that the...
Neutrinos emitted from the core collapse supernovae (CCSNe) can be generally studied to explore both the supernova explosion mechanism and neutrino properties. One of the most interesting properties is the neutrino mass ordering (NMO). Large scale liquid scintillator (LS) detectors, i.e., with tens of kiloton scale, show superior on CCSNe neutrino detection especially benefited from the large...
The large-scale $B$-mode polarisation of the Cosmic Microwave Background (CMB) represents one of the most powerful sources of information about the high-energy physics taking place in the early Universe. If detected, the most likely explanation for this signature would be the emission of primordial gravitational waves after the Big Bang, which would carry valuable information about the physics...
