北半球TeV伽马射线观测站,如Milagro和Tibet AS $γ$,通过发现以前未被识别的源,可能是PeVatron产生的宇宙射线谱中高达“膝盖”的宇宙射线,证明了全天空仪器的重要性。我们评估冰立方的潜力,以确定类似的源在南部天空中的详细分析方法,以确定通量的μ子从TeV的伽马射线阵雨。我们将这种方法应用于已知的伽马射线源,如超新星遗迹。我们发现,与米拉格罗类似,对于通量强于几个10^{-11}粒子TeV^{-1} cm^{-2} s^{-1}的点状PeVatron,在10年内就有可能探测到。
英文摘要:
Northern hemisphere TeV gamma-ray observatories such as Milagro and Tibet AS$γ$ have demonstrated the importance of all-sky instruments by discovering previously unidentified sources that may be the PeVatrons producing cosmic rays up to the "knee" in the cosmic ray spectrum. We evaluate the potential of IceCube to identify similar sources in the southern sky by detailing an analytic approach to determine fluxes of muons from TeV gamma-ray showers. We apply this approach to known gamma-ray sources such as supernova remnants. We find that, similar to Milagro, detection is possible in 10 years for point-like PeVatrons with fluxes stronger than several 10^{-11} particles TeV^{-1} cm^{-2} s^{-1}.
Measuring the Astrophysical Galactic Plane Neutrino Flux and Searching for Galactic PeVatrons using the IceCube Multi-Flavor Astrophysical Neutrino Sample
Recently, Large High Altitude Air Shower Observatory (LHAASO) has detected several Galactic point sources of ultra high energy (UHE; $E_γ> 100$ TeV) gamma-rays. These gamma-rays are possibly created in leptonic or hadronic interactions of cosmic rays (CRs) of PeV energies. In the hadronic channel ($p-p$ interaction), the gamma-rays are accompanied by neutrinos. The detection of neutrinos is therefore crucial in understanding CR acceleration in such objects. To estimate the neutrino flux, we adopt the two LHAASO sources (J2226+6057, J1908+0621) found to be spatially associated with the Supernov…
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; optimisation of the angular resolution to mitigate source confusion between known TeV sources; and studies of the energy resolution and sensitivity required to study the spectral features of PeVatrons at th…
IceCube has discovered a flux of astrophysical neutrinos, and more recently has used muon-neutrino datasets to present evidence for one source; a flaring blazar known as TXS 0506+056. However, the sources responsible for the majority of the astrophysical neutrino flux remain elusive. Opening up new channels for detection can improve sensitivity and increase the discovery potential. In this work we present a new neutrino dataset relying heavily on Deep-Neural-Networks (DNN) to select cascade events produced from neutral-current interactions of all flavors and charged-current interactions with f…
The candidate PeVatron MGRO J1908+06, which shows a hard spectrum beyond 100 TeV, is one of the most peculiar $γ$-ray sources in the Galactic plane. Its complex morphology and some possible counterparts spatially related with the VHE emission region, preclude to distinguish between a hadronic or leptonic nature of the $γ$-ray emission. In this paper we illustrate a new multiwavelength analysis of MGRO J1908+06, with the aim to shed light on its nature and the origin of its ultra high-energy emission. We performed an analysis of the $^{12}$CO and $^{13}$CO molecular line emission demonstrating …
The IceCube Neutrino Observatory is a cubic kilometer-sized detector designed to detect neutrinos of astrophysical origin. However, muons created by cosmic rays interacting in the atmosphere pose a significant background for these astrophysical neutrinos particularly in the southern equatorial sky. Identifying neutrino events that start in the detector allows us to reduce the atmospheric muon component while retaining a high rate of starting neutrino events. The method presented today also rejects atmospheric neutrinos if they are accompanied by muons from the same cosmic ray shower, lowering …
The South Pole, which hosts the IceCube Neutrino Observatory, has a complete and around-the-clock exposure to the Galactic Center. Hence, it is an ideal location to search for gamma rays of PeV energy coming from the Galactic Center. However, it is hard to detect air showers initiated by these gamma rays using cosmic-ray particle detectors due to the low elevation of the Galactic Center. The use of antennas to measure the radio footprint of these air showers will help in this case, and would allow for a 24/7 operation time. So far, only air showers with energies well above 10 PeV have been det…
The IceCube Observatory has collected over 577 billion cosmic-ray induced muon events in its final configuration from May 2011 to May 2020. We used this data set to provide an unprecedented statistically accurate map of the cosmic ray arrival direction distribution in the TeV-PeV energy range scale in the Southern Hemisphere. Such an increase in event statistics makes it possible to extend the sensitivity to anisotropies at higher cosmic ray energies and smaller angular scales. It will also facilitate a more detailed assessment of the observatory stability over both short- and long-time scales…
XMM-Newton Resolves Parsec-scale X-ray Jets in the PeVatron Microquasar V4641 Sgr
Institute for Cosmic Ray Research, The University of Tokyo(宇宙线研究所,东京大学);Interdisciplinary Theoretical & Mathematical Science Center (iTHEMS), RIKEN(理化学研究所交叉理论与数学科学中心(iTHEMS));INAF-Osservatorio Astronomico di Brera(意大利国家天体物理研究所布雷拉天文台);Como Lake Center for Astrophysics (CLAP), DiSAT, Università degli Studi dell’Insubria(因苏布里亚大学地球科学与技术系科莫湖天体物理中心);Columbia Astrophysics Laboratory, Columbia University(哥伦比亚大学哥伦比亚天体物理学实验室);The University of Miyazaki(宫崎大学);Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences(中国科学院高能物理研究所粒子天体物理重点实验室);Tianfu Cosmic Ray Research Center(天府宇宙线研究中心);Department of Physics and Astronomy, University of Manitoba(曼尼托巴大学物理与天文学系);Anton Pannekoek Institute for Astronomy, University of Amsterdam(阿姆斯特丹大学安东·潘内库克天体物理研究所)
Multimessenger Concordance for the Cygnus Region as the Source of the Cosmic-Ray Knee
Gran Sasso Science Institute(格兰萨索科学研究所);INFN, Laboratori Nazionali del Gran Sasso(意大利国家核物理研究所,格兰萨索国家实验室);The Pennsylvania State University(宾夕法尼亚州立大学);Yukawa Institute for Theoretical Physics(京都大学汤川理论物理研究所);University of L’Aquila(拉奎拉大学);INAF Osservatorio Astrofisico di Arcetri(意大利国家天体物理研究所阿切特里天文台);Shanghai Jiao Tong University(上海交通大学)
The Large High Altitude Air Shower Observatory (LHAASO) observed a dozen of gamma-ray sources with significant emission above 100 TeV, which may be strong candidates of PeVatrons. Neutrino observations are crucial to diagnose whether the gamma-ray radiative process is hadronic or leptonic. We use the Bayesian method to analyze the ten-year (2008-2018) IceCube data, and hence constrain the hadronic gamma-ray emission in the LHAASO sources. The present neutrino data show that the hadronic gamma-ray flux from Crab Nebula is lower than the observed gamma-ray flux at the 90% C.L. and contributes le…
Recent findings by the LHAASO experiment are opening a new window, that of the PeV sky, to the observation of the electromagnetic spectrum. Several astronomical objects emitting gamma-rays at energies well above 100 TeV have been observed with the LHAASO-KM2 array of scintillators and muon detectors, clearly demonstrating the feasibility of gamma-ray astronomy up to PeV energies. An all-sky gamma-ray detector in the Southern Hemisphere, operating in the GeV-PeV range, could complement LHAASO observations, monitor the Inner Galaxy and the Galactic Center looking for PeVatrons. As shown by LHAAS…
Recent observations by the Large High Altitude Air Shower Observatory (LHAASO) have paved the way for the observational detection of PeVatrons in the Milky Way Galaxy, thus revolutionizing the field of $γ$-ray astrophysics. In this paper, we study one such detected source, LHAASO J1908+0621, and explore the origin of multi-TeV $γ$-ray emission from this source. A middle-aged radio supernova remnant SNR G40.5-0.5 and a GeV pulsar PSR J1907+0602 are co-spatial with LHAASO J1908+0621. Dense molecular clouds are also found to be associated with SNR G40.5-0.5. We explain the multi-TeV $γ$-ray emiss…