Conveners
Astro-particle Physics and Cosmology: 1
- Seong Chan Park (Yonsei University)
Astro-particle Physics and Cosmology: 2
- Carsten Rott (Sungkyunkwan University)
Astro-particle Physics and Cosmology: 3
- Seong Chan Park (Yonsei University)
Astro-particle Physics and Cosmology: 4
- Andrei Kounine (Massachusetts Inst. of Technology (US))
Astro-particle Physics and Cosmology: BSM+ASTRO Joint Session
- Seong Chan Park (Yonsei University)
Astro-particle Physics and Cosmology: 5
- Andrei Kounine (Massachusetts Inst. of Technology (US))
Astro-particle Physics and Cosmology: 6
- Javier Berdugo Perez (Centro de Investigaciones Energéti cas Medioambientales y Tecno)
Astro-particle Physics and Cosmology: 7
- Andrei Kounine (Massachusetts Inst. of Technology (US))
Astro-particle Physics and Cosmology: 8
- Carsten Rott (Sungkyunkwan University)
The Ultra-Light Axion (ULA) is a dark matter candidate with mass 10^{-22} eV and
de-Broglie wavelength of order kpc. Such an axion, also called the Fuzzy Dark Matter (FDM), thermalizes via the gravitational force and forms a Bose-Einstein condensate. The quantum pressure from FDM can significantly affect the structure formation in small scales, thus alleviating the so-called "small-scale...
Big-Bang nucleosynthesis (BBN) represents one of the earliest phenomena which can lead to observational constraints on the early Universe properties. Yet, it is well-known that many important mechanisms and phase transitions occurred before BBN. During this talk, I will discuss the possibility to gain insight about the primordial Universe through studies of dark matter in cosmology,...
We investigate a scenario of Strongly Interacting Massive Particles (SIMPs) where the thermal relic density of dark pion dark matter (DM) is determined by number changing 3→2 annihilations in a strongly interacting dark sector. In this scenario, including dark vector mesons in the hidden local symmetry scheme, we find that dark vector mesons unitarize the dark chiral perturbation theory (ChPT)...
In the early Universe, there exists a matter-dominated era, that is driven by inflaton oscillation, curvaton, moduli or long-lived heavy particles. In this early matter domination, dark matter exists and show different behavior from the standard one during radiation domination, from the relics density to the density perturbation, constraints on the reheating temperature and baryogengesis. In...
The relaxion mechanism provides a potentially elegant solution to the hierarchy problem without resorting to anthropic or other fine-tuning arguments. This mechanism introduces an axion-like field, dubbed the relaxion, whose expectation value determines the electroweak hierarchy as well as the QCD strong CP violating θ parameter. However, in the original model proposed by Graham, Kaplan and...
Following a fruitful Observation Run 2 (O2, November 2016 - August 2017) marked by the first three-detector observation of a binary black hole merger and the first ever detection of a binary neutron merger followed by the discovery of the optical counterpart of the gravitational-wave signal, the LIGO and Virgo giant interferometers started a new upgrade phase with a twofold goal: to improve...
In this work, inflationary models with Gauss-Bonnet term is classified into two categories based on their prediction for the tensor spectral index ($n_T$). We showed that the energy spectrum of the primordial gravitational waves (GWs) induced by a group of models that predict blue-tilted tensor spectrum ($n_T>0$) can be probed by the future space-based laser interferometer experiment such as...
We present a new phenomenology for the Fermilab Holometer, a pair of 39m-long, co-located but independent high-power Michelson interferometers. The differential position signals are cross-correlated over a broad frequency band exceeding the inverse light crossing time, attaining sensitivity to both timelike and spacelike correlations across the physical system. The second-generation...
While grand unified theories offer potential solutions to problems with the Standard Model, such as the origins of charge quantization, their signature prediction, proton decay, has not been observed experimentally. Hyper-Kamiokande is a next-generation water Cherenkov experiment with a 187~kton target volume that will provide unprecedented sensitivity to a variety of nucleon decay modes,...
Among cosmological relaxation solutions to the weak-scale hierarchy problem, gauge boson production is a particularly efficient backreaction mechanism for trapping the relaxion. In these models, scanning can even happen after inflation and the relaxion field range can be sub-Planckian, with no extremely small parameters or large e-foldings involved. We consider a model where particle...
We propose a minimal extension of the standard model with U(1)_B−L × Z_2 symmetry. In this model by assuming that the neutrinos are Dirac (i.e. B − L is an exact symmetry), we found a simultaneous solution for non zero neutrino masses and dark matter content of the universe. The observed baryon asymmetry of the universe is also explained using Dirac Leptogenesis, which is assisted by a dark...
I will show that the baryon asymmetry of the Universe (BAU) is generated from the hypermagnetic helicity decay without being washed out by the sphalerons. Moreover such hypermangetic fields still remain until today as the intergalactic magnetic fields, which will be the smoking gun of the scenario. I will also discuss a possible mechanism to generate such hypermagnetic fields. That is, the...
We propose a WIMP baryogensis achieved by the annihilation of non-thermally produced WIMPs from decay of heavy particles, which can result in low reheating temerature. Dark matter (DM) can be produced non-thermally during a reheating period created by the decay of long-lived heavy particle, and subsequently re-annihilate to lighter particles even after the thermal freeze-out. The...
We discuss the early-universe cosmology of a Kaluza-Klein (KK) tower of scalar fields in the presence of a mass-generating phase transition, focusing on the time-development of the total tower energy density as well as its distribution across the different KK modes. We find that both of these features are extremely sensitive to the details of the phase transition and can behave in a variety...
Axions or axion-like particles are ubiquitous in many theoretical extensions of the Standard Model of particle physics, in particular the ''string axiverse'' scenario [1-3]. If the phenomenologically defining parameters, the axion mass, $m_a$, and (effective) decay constant, $f_a$, fall in specific ranges, then axions contribute to the cosmological dark matter and dark energy densities of the...
In standard model of cosmology, B-mode polarization of the CMB can be generated due to the tensor perturbation of metric which is related to gravitational effects in the inflation epoch and scalar perturbation can not explain B-mode polarization. We consider Compton scattering in non-commutative framework and show that Compton scattering in presence of non-commutative background and scalar...
Telescope Array (TA) is the largest cosmic ray detector in the Northern hemisphere, constructed to study ultra high energy cosmic rays (UHECRs) with energies above 10^18 eV. The TA consists of an array of scintillation counters with 1200 m spacing and three fluorescence detectors, each viewing 3 to 30 degrees in elevation. The TA has also added a facility (TALE) to extend the energy threshold...
Ultra-high energy cosmic rays (UHECR) can be used to study hadronic interactions beyond LHC energies. In this contribution we summarize relevant data from the Pierre Auger Observatory.
While the proton-air cross section has been measured at sqrt(s) = 57 TeV and found to be in good agreement with extrapolations from LHC energies, other observables are significantly different to what is...
The main aim of the LHC forward (LHCf) experiment [1] is to provide precise measurements of the particles production rate in the forward region. These high energy calibration data are very important for the tuning of hadronic interaction models used by ground-based cosmic rays experiments. LHC is the most suitable place where we can perform these measurements because a proton-proton collision...
Horizon-8T is a detector system aimed to study Extensive Air Showers (EAS) temporal structure in the energy range of the primary above ~10^16 eV. It is constructed at approximately 3340 meters above the sea level at the Tien Shan high-altitude Science Station, part of Lebedev Physical Institute of the Russian Academy of Sciences. Detector system consists of eight charged particle detection...
Having no new physics signals observed at collider experiments, we are motivated to consider a scenario that the new physics scale is higher than the current collider energies but still within the reach of the cosmic ray experiments covering beyond TeV scale. In particular, we focus on the types of new physics interactions accompanying with high multiplicities in their signals from the...
It will be pointed out that lepton asymmetry can be generated through CP-preserving inflaton decay into leptons when the Pontecorvo–Maki–Nakagawa–Sakata matrix has proper CP phases. Except for the assumption of the inflaton decay, we do not introduce any new particle.
In this letter we have explored the possibility of embedding the genesis
of lepton asymmetry within the well studied Scotogenic model. We have shown that in this model one can have a Dark Matter in the TeV scale. The model is highly constrained in the context of dark matter,neutrino mass, Flavor Physics and now also gets an additional
constraint on the relative complex phases from the...
We provide the first systematic study of the low-scale leptogenesis scenario in the minimal Standard Model extended with 3 right-handed neutrinos having masses at the GeV scale.
We highlight and discuss the differences between the 2- and the 3-right-handed neutrino cases, the major qualitative distinction being the possibility, in the latter scenario, of probing part of the parameter space at...
I present results from [1711.09912][1] of frequentist and Bayesian statistical analyses of Higgs- and Z-portal models of dark matter particles with spin 0, 1/2 and 1. Our analyses incorporate data from direct detection and indirect detection experiments, as well as LHC searches for monojet and monophoton events. We find acceptable regions of the parameter spaces for Higgs-portal models with...
First-order electroweak phase transition plays a central role in electroweak baryogenesis.
However, it is known that unwanted gauge dependence exists in critical temperature
and Higgs vacuum expectation value in an ordinary perturbative calculation scheme.
In this talk, we revisit the electroweak phase transition in the SM with a singlet scalar
utilizing a gauge-independent method proposed...
The precision measurement of primary cosmic rays fluxes (in particular helium, carbon and oxygen) in the rigidity range from 2 GV to 3 TV is presented based on 90 million helium, 8 million carbon and 7 million oxygen nuclei collected by the Alpha Magnetic Spectrometer during its first 5 years of operation.
Unexpectedly, above 60 GV, these three spectra have identical rigidity dependence,...
We report on the observation of new properties of secondary cosmic rays Li, Be, and B measured in the rigidity (momentum per unit charge) range 1.9 GV to 3.3 TV with a total of 5.4 million nuclei collected by AMS during the first five years of operation aboard the International Space Station. The Li and B fluxes have an identical rigidity dependence above 7 GV and all three fluxes have an...
The nitrogen flux in cosmic rays is expected to contain both primary and secondary components, so the knowledge of their relative contributions is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the nitrogen flux with rigidity from 2 GV to 3 TV based on 2 million nuclei collected by AMS during first 5 years of operation is presented.
The spectral shape of the secondary isotopes in cosmic rays is completely determined by the source spectrum of the parent elements and by the propagation process. In particular, 3He in cosmic rays is believed to result from the interaction of primary 4He with the interstellar medium, providing a powerful tool to constrain the parameters of the galactic cosmic rays propagation models. A precise...
Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron and positron fluxes in the energy range up to 1000 GeV are presented. The electron flux and the positron flux are significantly different in their magnitude and energy dependence. Their behavior is consistent with the contribution from a new source of high energy...
The fluxes and flux ratios of charged elementary particles in cosmic rays are presented in the absolute rigidity range from 1 to 1000 GV. In the absolute rigidity range ∼60 to ∼500 GV, the antiproton, proton, and positron fluxes are found to have nearly identical rigidity dependence and the electron flux exhibits different rigidity dependence. Below 60 GV, the antiproton-to-proton,...
Analysis of anisotropy of the arrival directions of galactic protons, electrons and positrons has been performed with the Alpha Magnetic Spectrometer on the International Space Station. These results allow to differentiate between point-like and diffuse sources of cosmic rays for the explanation of the observed excess of high energy positrons. The AMS results on the dipole anisotropy are...
The precision measurements of the monthly cosmic ray fluxes for the period from May 2011 to May 2017 with Alpha Magnetic Spectrometer on the International Space Station are presented. This period covers the ascending phase of solar cycle # 24 together with the reversal of the Sun's magnetic field polarity through the minimum. The detailed variations with time of the fluxes are shown up to...
The 6-year dataset of high-energy starting events (HESE) at IceCube indicates a spectrum of astrophysical neutrinos much softer than expected from the Fermi shock acceleration mechanism. On the other hand, IceCube's up-going muon neutrino dataset and Fermi-LAT's gamma-ray spectrum point to an $E^{-2}$ neutrino spectrum. If the HESE data above 200 TeV are fit with the latter flux, an excess at...
Cosmic ray interactions with the solar atmosphere are expected to generate energetic neutrinos that might be observable with the neutrino telescopes. These so called solar atmospheric neutrinos are expected to have a distinguishable shape in the energy spectrum compared with atmospheric neutrinos generated in the Earth. The difference originates from the lower atmospheric density on the Sun,...
Dark matter particles may be metastable. If they decay into neutrinos, directly or indirectly, the signal is detectable with a neutrino telescope like IceCube, located at the geographic South Pole. IceCube instruments a cubic kilometre of ice with over 5000 optical sensors which detect the Cherenkov light emitted by particles produced in neutrino interactions in the ice. This talk will...
To date the neutrino telescopes IceCube and ANTARES have been generating strong limits on the thermally averaged annihilation cross-secttion of WIMP dark matter in the galactic center, with ANTARES yeilding the currently strongest limits at WIMP masses exceeding 30 TeV. At a WIMP mass range of 50 GeV to a few hundred GeV the current limitss from IceCube surpass those of ANTARES offering a good...
The ANTARES detector, located 40 km off the French coast, is
the largest deep-sea neutrino telescope in the Northern Hemisphere
with an instrumented volume of more than 0.01 cubic kilometers. It has
been taking data continuously since 2007. The primary goal of such a
telescope is to search for astrophysical neutrinos in the TeV-PeV
range. The latest results from ANTARES will be presented,...
The detection of ultra-high-energy (UHE) neutrinos, with energy in excess of 108 GeV, is an important key to solving the mystery of the origin of UHE cosmic rays. The detection of UHE cosmogenic neutrinos will confirm the photo-dissociation of UHE cosmic rays and the identification of the sources of UHE neutrinos will help to identify the sources of UHE cosmic rays.
The flux of...
Supernova relic neutrinos (SRN), also called the diffused supernova neutrino backgrounds (DSNB), are emitted from core-collapse supernovae throughout the universe. Super-Kamiokande-IV tags inverse beta interactions by neutrons captured on hydrogen using improved electronics and triggering. Recently, the use of vertex reconstruction of the 2.2 MeV photons emitted by the neutron captures and a...
Neutrino has become a new window to our universe since the observation
of neutrinos from the Sun and SN1987A. Hyper-Kamiokande (Hyper-K) is
a next-generation neutrino telescope with excellent capabilities in particle physics. The detector will be a water Cherenkov detector of 260 kton water mass with 40 % photo coverage. With about 10 times larger fiducial volume per detector than Super-...
The space experiment of DArk Matter Particle Explorer (DAMPE) developed in China is designed to find the evidence of dark matter particle by observing primary cosmic rays and gamma rays in energy range from 5 GeV to 10 TeV. Since its launch in December 2015, a large quantity of data has been recorded.
The BGO Electromagnetic Calorimeter (BGO ECAL) of the DAMPE is a total absorption calorimeter...
DAMPE (DArk Matter Particle Explorer) is a satellite mission of the Chinese Academy of Sciences (CAS) dedicated to high energy cosmic ray detections. Since its successful launch on December 17th, 2015 a large amount of cosmic ray data has been collected. With relatively large acceptance, DAMPE is designed to detect electrons (and positrons) up to 10 TeV with unprecedented energy resolution to...
Direct measurements of cosmic-rays (CRs) are important to understand the sites and the processes of acceleration and propagation of high-energy particles in the interstellar medium. For example, detailed measurements of the high-energy electron+positron (hereafter simply “electron”) spectrum can provide information about nearby CR sources. The electron spectrum may also exhibit features from...
Precision measurements by AMS of the positron fraction and the combined electron and positron flux in primary cosmic rays in the energy range from up to 1000 GeV based on 25 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show that at ∼300 GeV the positron fraction reaches its...
The CREAM experiment was launched on a SpaceX Falcon 9 rocket to the International Space Station (ISS) from NASA’s Kennedy Space Center on August 14, 2017. The instrument was successfully installed and activated on the ISS Japanese Experiment Module Exposed Facility as an attached payload on August 22, 2017. The CREAM instrument was initially developed to measure cosmic ray elemental spectra...
The Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM) is a space-borne mission designed for the precision measurement of energy and elemental composition of cosmic rays. It was launched and installed on the ISS in August 2017. The Silicon Charge Detector (SCD), placed at the top of the ISS-CREAM payload, consists of 4 layers. Each layer has 2688 silicon...
Experiments aiming to directly detect dark matter (DM) particles have yet to make robust detections, thus underscoring the need for complementary approaches such as searches for new particles at colliders, and indirect searches of DM decay or annihilation signatures in photon and cosmic ray spectra. In particular, low energy ($<$ 0.25 GeV/n) cosmic ray antiparticles such as antideuterons are...
Recent measurements of cosmic ray proton and helium spectra in CREAM, PAMELA and AMS02 experiments show a hardening above a few hundreds of GeV. This excess is hard to understand in the framework of the conventional models of Galatic cosmic ray production and propagation. We propose here to explain this anomaly by the presense of the local sources as a discrete one. Improving the Green...
A key observation has been reported in 2013 (Eatough et al., 2013): an abnormally strong radial magnetic field near the GC is discovered.
Firstly, we demonstrate that the radiations observed from the GC are hardly emitted by the gas of accretion disk which is prevented from approaching to the GC by the abnormally strong radial magnetic field and these radiations can't be emitted by the black...
A few examples for the light dark matter will be
presented along with their cosmological (e.g. radio astronomy search) and
the particle physics (dark matter search experiments) constraints to illustrate the complementarity between the particle physics and cosmology probes.
Since 2013, the Dark Energy Survey (DES) has been mapping an entire octant of the sky to unprecedented depth, measuring the position on the sky, redshift and shape of over 200 million galaxies, together with thousands of galaxy clusters and supernovae. With this data set, DES is studying the properties of dark energy using four main probes: galaxy clustering on large scales, weak gravitational...
We study a model of a keV-scale sterile neutrino with a relatively large mixing with the Standard Model sector. Usual considerations predict active generation of such particles in the early Universe, which leads to constraints from the total Dark Matter density and absence of X-ray signal from sterile neutrino decay. These bounds together may deem any attempt of creation of the keV scale...
