Conveners
Session 2: Galactic sources(1poster)
- Yang Chen (Department of Astronomy, Nanjing University)
Session 2: Cosmic rays
- Damiano Caprioli ()
Session 2: Extragalctic sources
- Andrew Taylor ()
Session 2: Extragalactic sources+others
- Katsuaki Asano ()
Session 2: Particle physics+others
- Jiji Fan ()
- Lesya Shchutska (E)
Session 2: Particle physics
- Jiji Fan (Brown University)
- Lesya Shchutska (E)
Sonal Ramesh Patel
(D)
26/10/2021, 15:20
oral
We present multi-waveband studies of the TeV gamma-ray binary, LS I +61° 303. LS I +61° 303 displays variable emission from radio to TeV, modulated with the orbital period of 26.5 days, and with a spectral energy distribution peaking at MeV-GeV energies. The imaging atmospheric Cherenkov telescope array, VERITAS, has been observing this binary since November 2006 and has collected a rich...
Dr
Atreyee SINHA
(LUPM, CNRS)
26/10/2021, 15:40
oral
Cosmic Ray (CR) interactions with the dense gas inside Giant Molecular Clouds (GMCs) produce neutral pions, which in turn, decay into gamma rays. Because of the high target density for CRs in GMCs the study of gamma-ray emission from GMCs can yield a model-independent insight into the spatial and spectral properties of CRs without any significant contamination by other sources. While multiple...
Ruben Lopez-Coto
(I)
26/10/2021, 16:00
oral
The Southern Wide-field Gamma-ray Observatory (SWGO) is a proposed ground-based gamma-ray detector that will be located in the Southern Hemisphere and is currently in its design phase. In this contribution, we will outline the prospects for Galactic science with this Observatory. Particular focus will be given to the detectability of extended sources, such as gamma-ray halos around pulsars;...
Veronika vodeb
(University of Nova Gorica)
26/10/2021, 16:20
oral
Pulsar halos constitute a recently identified TeV class of sources that will be observed with the upcoming Cherenkov Telescope Array (CTA), especially in the context of the Galactic Plane Survey (GPS), one of the Key Science Projects of CTA. In this study, we examine the prospects offered by CTA for the detection and characterization of such objects. CTA will cover energies from 20 GeV to 300...
Gwenael Giacinti
(MPIK Heidelberg)
26/10/2021, 17:00
oral
We study electron and positron acceleration at the termination shock of a striped pulsar wind by integrating particle trajectories in a prescribed model of the magnetic field and flow pattern. We find that drift motion on the shock surface maintains either electrons or positrons on Speiser orbits in a ring-shaped region close to the equatorial plane of the pulsar, where they are accelerated to...
Mr
Yiwei Bao
(Nanjing University)
26/10/2021, 17:20
oral
Multi-wavelength observations indicate that there must be a hadronic component in the $\gamma$-ray spectrum of SNR G106.3+2.7. However, fitting the hard $\gamma$-ray spectrum requires a hard proton spectrum, while usual observations and recent numerical simulations prefer a soft proton
spectrum. Here we explore an alternative scenario to explain the γ-ray spectrum
of G106.3+2.7 within the...
Dr
Robert Brose
(DIAS)
26/10/2021, 17:40
oral
Supernova remnants (SNRs) are known to accelerate particles to relativistic energies, on account of their nonthermal emission. The particularities of the acceleration mechanism are still debated and here we discuss how particle escape modifies the observable spectra as well as morphological features that might be revealed by the observational progress from radio to gamma-ray energies.
We...
Arnau Aguasca-Cabot
(Universitat de Barcelona)
26/10/2021, 18:00
poster
The Cherenkov Telescope Array (CTA) prototype Large-Sized Telescope (LST-1) was inaugurated in 2018 and, after its commissioning, it is progressively entering the scientific data taking phase. In this contribution, we present a dedicated study on the capability of LST-1 to probe the very high energy (VHE) emission from galactic transient sources. Making use of numerical simulations of the VHE...
Ms
Rebecca Diesing
(University of Chicago)
27/10/2021, 08:30
oral
Galactic cosmic rays (CRs) are accelerated by astrophysical shocks, primarily supernova remnants (SNRs), via diffusive shock acceleration (DSA), an efficient mechanism that predicts power-law energy distributions of CRs. However, observations of both nonthermal SNR emission and Galactic CRs imply CR spectra that are steeper than the standard DSA prediction, $\propto E^{-2}$. Recent kinetic...
Ms
Liping wang
(SDU IHEP)
27/10/2021, 08:50
oral
The longitude development of the muonic component in the extensive air shower can help to determine mass composition of cosmic rays. By using the timing information of muons, the production positions of muons can be reconstructed . X_max^μwhich is the position with muon production reaching maximum is sensitive to the mass composition of cosmic rays. In this paper, the reconstruction of muon’s...
Xiaoting Feng
(Shandong University)
27/10/2021, 09:10
oral
The muons number observed at the ground from air showers is sensitive to the mass composition of cosmic rays and hadronic interaction model, the attenuation length of these muons will affect the measurement of the muon number. The muon detectors of LHAASO KM2A can directly measure the muons number in the air shower. Using the data recorded by the first-quarter array of KM2A in August 2020, the...
Dr
Jingjing Zang
(Linyi University)
27/10/2021, 09:50
oral
The Forbush Decrease (FD) represents the rapid decrease of the intensities of charged particles accompanied with the coronal mass ejections (CMEs) or high-speed streams from coronal holes. We study the FD event occurred in September, 2017, with the electron and positron data recorded by the Dark Matter Particle Explorer. The evolution of the FDs from 2 GeV to 20 GeV with a time resolution of 6...
Chengming LIU
(USTC)
27/10/2021, 10:10
oral
The existence of fractionally charged particles (FCP) in present is some extensions to the Standard Model of particle physics, and their detection would be a significant breakthrough. Most of the previous cosmic-rays (CRs) studies are mainly focused on the secondary CRs from the extensive air shower, but there is rarely on-orbit study to search FCP from primary CRs. The DArk Matter Particle...
Dr
Jia-Shu Niu
(Shanxi University)
27/10/2021, 10:30
oral
Many experiments have confirmed the spectral hardening at a few hundred GV of cosmic-ray (CR) nuclei spectra, and 3 general different origins have been proposed: the primary source acceleration, the propagation, and the superposition of different kinds of sources. In this talk, I will report some new findings from the AMS-02 nuclei spectra of B and its dominating parents species (C, N, O, Ne,...
Yusuke Suda
(Hiroshima University)
27/10/2021, 15:00
oral
TeV gamma-ray telescopes are the established energy frontier in gamma-ray burst study. Starting from a bright long GRB 190114C detected by the MAGIC telescopes, there are three published long GRB detections together with the H.E.S.S. In order to understand this newly revealed nature of GRBs, further detections are longing and investigation with a large sample of non-detected GRBs is important....
Mr
Zhiqiu Huang
(MPIK)
27/10/2021, 15:20
oral
We revisit the external shock picture of gamma-ray burst afterglow models, in light of recent very-high-energy gamma-ray detection from GRB190829A. The maximum electron energy achievable at an ultra-relativistic weakly-magnetized shock is thought to proceed in the "ballistic" transport regime. This limits synchrotron photons to energies below the often assumed burn-off limit. A single zone...
Ilaria Viale
(University and INFN Padova)
27/10/2021, 16:00
oral
The evidence for multi-messenger photon and neutrino emission from the blazar TXS 0506+056 has been a major success for the astrophysical community, reached thanks to a powerful strategy of real-time follow-up of neutrino events. The effort of MAGIC and other experiments in coordinating observations to obtain contemporaneous multiwavelength (MWL) flux and spectral measurements was key for...
Serena Loporchio
(I)
27/10/2021, 16:20
oral
BL Lac objects which possess a synchrotron peak at unusually high X-ray frequencies (peak_S ≥10^17 Hz) were categorized as extreme high-frequency BL Lacs (EHBLs) by Costamante et al. (2001). As a consequence of the location of the synchrotron peak, the inverse Compton hump of EHBLs is expected to peak in the gamma-ray band, making them interesting targets for very-high-energy gamma rays...
Dr
Vitalii Sliusar
(University of Geneva)
27/10/2021, 17:00
oral
Markarian 421 (Mrk 421) and Markarian 501 (Mrk 501) are two close bright and well-studied high-synchrotron-peaked blazars, which feature bright and persistent GeV and TeV emission. We use the longest and densest dataset of unbiased observations of these two sources, obtained at TeV and GeV energies during 5 years with the FACT telescope and Fermi LAT. To characterize the variability and derive...
Axel Arbet-Engels
(Max Planck Institute for Physics)
27/10/2021, 17:20
oral
Thanks to its brightness and proximity, the BL Lac type object Mrk 421 is an ideal target to probe blazar jet physics. We present a detailed characterisation and theoretical interpretation of the broadband emission of Mrk 421, focusing on the multi-band flux correlations. The analysis makes use of an extensive multi-wavelength campaign organised in 2017, during which the correlation patterns...
Dr
Francesco de Palma
(UniSalento & INFN Lecce)
27/10/2021, 17:40
oral
QSO B0218+357 (z = 0.944±0.002 ) is currently the only gravitationally lensed source from which very-high-energy (VHE, >~100GeV) gamma-ray emission has been detected. We report the Fermi-LAT monitoring of the source between 2016 and 2020 in conjunction with multiwavelength monitoring observations in radio interferometry and in the optical, X-ray, and VHE ranges. During the monitoring,...
Mr
Mahmoud Alawashra
(University of Potsdam)
27/10/2021, 18:00
oral
We constrain the intermediate-scale intergalactic magnetic field (IGMF) through its suppression of the electrostatic instability for blazar-induced pair beams. IGMF of Femto-Gauss strength is sufficient to significantly deflect the TeV pair beams, which reduces the flux of secondary cascade emission below the observational limits. A similar flux reduction may result from the electrostatic...
Dr
Rui Xue
(Zhejiang Normal University)
28/10/2021, 08:30
oral
In this work, we develop a self-consistent multi-zone model to describe the time-dependent multi-wavelength emission of blazars. Based on Very Long Baseline Array observations of M 87 jet, we speculate and assume that numerous discrete emission zones throughout the jet of a blazar. We model the temporal evolution of the electron spectrum in each emission zone taking into account the injection,...
Zerui WANG
(Qilu Normal University)
28/10/2021, 08:50
oral
Blazars are a class of active galactic nuclei which host relativistic jets oriented close to the observer's line of sight. Blazars have very complex variability properties. Flares, namely flux variations around the mean value with a well-defined shape and duration, are one of the identifying properties of the blazar phenomenon. Blazars are known to exhibit multi-wavelength flares, but also...
Tomohisa Kawashima
(ICRR, U of Tokyo)
28/10/2021, 09:10
oral
The Event Horizon Telescope (EHT) detected the black hole shadow in the elliptical galaxy M87*. This provided powerful evidence of the presence of supermassive black holes and the mass of the black hole was estimated to be ~6.5 billion solar mass.
For revealthe magnitude of the black hole spin and the dynamics of relativistic jets and accretion flows near the event horizon by future EHT...
Dr
Xin-Yue Shi
(Nanjing University)
28/10/2021, 10:10
oral
High-energy cosmic rays (CRs) can be accelerated in the relativistic jets of Active Galactic Nuclei (AGNs) powered by supermassive black holes.
The baryon loading efficiency onto relativistic CR baryons from the accreting black holes is poorly constrained by observations so far. In this presentation, we suggest that the $\gamma$-ray emission of galaxy clusters can be used to study the baryon...
Mr
Ryo Imazawa
(Hiroshima University)
28/10/2021, 10:30
oral
M87 is one of the nearest radio galaxy. We can study the core, jet, and some components by radio to X-ray observations.
Regarding TeV gamma ray observations, it is known to show an intra-day variability.
Such fast variability may occur at the particle acceleration region. But due to rough angular resolution, we cannot know which component causes this variability.
We searched for fast X-ray...
Kosuke Nishiwaki
(Institute for Cosmic-Ray Research)
28/10/2021, 10:50
oral
Galaxy clusters can work as gigantic reservoirs of cosmic rays, and they are considered to be possible sources of the IceCube neutrinos.
Some clusters are found with extended radio emission called radio halos, which provides crucial information about the non-thermal components in the intra-cluster medium. We study the high-energy emission from the galaxy clusters considering the constraints...
Lingfeng Li
(Brown University)
29/10/2021, 08:50
oral
We studied the phenomenology and experimental searches of the dark pions, which are the lightest hadrons in a hidden sector confining gauge theory. Such a scenario arises in many extensions of the Standard Model (SM). We consider that the leading interactions between the light hidden sector quarks and the SM particles come from the mixing of the light hidden quarks with heavy electroweak...
Mr
Yannis Georis
(Université Catholique de Louvain)
29/10/2021, 15:00
oral
In this talk, we present a new comprehensive study of the allowed parameter space within which type-I seesaw-based leptogenesis with three heavy neutrinos is possible. We include both freeze-in (ARS leptogenesis) and freeze-out (resonant leptogenesis) mechanisms. We show that, in presence of an approximately degenerate heavy neutrino mass spectrum, leptogenesis is feasible accross the whole...
Prof.
Bo-Qiang Ma
(Peking University)
29/10/2021, 15:20
oral
The Large High Altitude Air Shower Observatory~(LHAASO) is one of the most sensitive gamma-ray detector arrays currently operating at TeV and PeV energies. Recently the LHAASO experiment detected ultra-high-energy~(UHE) photon emissions up to $1.4~\mathrm{PeV}$ from twelve astrophysical gamma-ray sources. We point out that the detection of cosmic photons at such energies can constrain the...
Chiara Lucarelli
(CERN)
29/10/2021, 15:40
oral
Antimatter in cosmic rays is a powerful probe for the indirect
detection of Dark Matter. To constrain the background from secondary antiparticles, produced during cosmic ray propagation through the interstellar medium, the related cross sections need to be determined more precisely at accelerator facilities. The LHCb experiment currently offers the unique fixed-target facility exploiting the...
Malgorzata Kazana
(N)
29/10/2021, 16:00
oral
New particles with long lifetimes are introduced by many extensions to the standard model and would produce striking and non-conventional signatures in collider experiments such as long-lived charged particles, highly displaced jets, and particles that come to a rest within the detector and later decay. We present the results of several recent searches for long-lived particles with the CMS...
Sergio Grancagnolo
(CERN)
29/10/2021, 16:20
oral
Various theories beyond the Standard Model predict new, long-lived particles with unique signatures which are difficult to reconstruct and for which estimating the background rates is also a challenge. Signatures from displaced and/or delayed decays anywhere from the inner detector to the muon spectrometer, as well as those of new particles with fractional or multiple values of the charge of...
Peter BERTA
(Prague CU)
29/10/2021, 17:00
oral
The remarkably large integrated luminosity collected by the ATLAS detector at the highest proton-proton collision energy provided by LHC allows to use the large sample of top quark events to test theoretical predictions with unprecedented precision. Using data taken with the ATLAS detector at the LHC, recent measurements of total and differential top-quark cross sections as well properties of...
Marcella Bona
(Queen Mary University of London)
29/10/2021, 17:20
oral
The ATLAS experiment has performed measurements of B-meson rare decays proceeding via suppressed electroweak flavour changing neutral currents, and of mixing and CP violation in the neutral Bs meson system. This talk will focus on the latest results from the ATLAS collaboration, such as rare processes B0s → mu mu and B0 → mu mu, and CP violation in the B0s —> J/psi phi decays. In the latter,...
Angela Maria BURGER
(Oklahoma SU)
29/10/2021, 17:40
oral
Many theories beyond the Standard Model predict new phenomena, such as heavy vectors or scalar, and vector-like quarks, in final states containing bottom or top quarks. Such final states offer great potential to reduce the Standard Model background, although with significant challenges in reconstructing and identifying the decay products and modelling the remaining background. The recent 13...
Elliot REYNOLDS
(Berkeley LBNL)
29/10/2021, 18:00
oral
The discovery of the Higgs boson with the mass of about 125 GeV completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many measurements, it is not capable to solely explain some observations. Many extensions of the Standard Model addressing such shortcomings introduce additional Higgs-like bosons which can be either...
