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Fermi-detection of γ-ray Emissions from the Hot Coronae of Radio-quiet Active Galactic Nuclei

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arXiv 2025年

作者： Abdollahi, S. Ajello, M. Alves Batista, R. Baldini, L. Bartolini, C. Bastieri, D. Becerra Gonzalez, J. Bellazzini, R. Berenji, B. Bissaldi, E. Blandford, R.D. Bonino, R. Bruel, P. Buson, S. Cameron, R.A. Caraveo, P.A. Cavazzuti, E. Chiaro, G. Cibrario, N. Ciprini, S. Cristarella Orestano, P. Cutini, S. D’Ammando, F. Di Lalla, N. Dinesh, A. Di Venere, L. Domínguez, A. Fegan, S.J. Fiori, A. Franckowiak, A. Fukazawa, Y. Funk, S. Fusco, P. Gargano, F. Gasbarra, C. Gasparrini, D. Germani, S. Giglietto, N. Giliberti, M. Giordano, F. Giroletti, M. Green, D. Grenier, I.A. Guiriec, S. Hashizume, M. Hays, E. Hewitt, J.W. Horan, D. Hou, Xian Karwin, C. Kayanoki, T. Kuss, M. Laviron, A. Lemoine-Goumard, M. Li, Jian Liodakis, I. Liu, Jun-Rong Longo, F. Loparco, F. Lorusso, L. Lubrano, P. Maldera, S. Marcotulli, L. Martí-Devesa, G. Mazziotta, M.N. Mereu, I. Michelson, P.F. Mirabal, N. Mitthumsiri, W. Mizuno, T. Monzani, M.E. Morishita, T. Morselli, A. Moskalenko, I.V. Negro, M. Niwa, R. Omodei, N. Orienti, M. Orlando, E. Ormes, J.F. Paneque, D. Panzarini, G. Persic, M. Pesce-Rollins, M. Pillera, R. Porter, T.A. Principe, G. Rainò, S. Rando, R. Rani, B. Razzano, M. Reimer, A. Reimer, O. Sánchez-Conde, M. Saz Parkinson, P.M. Serini, D. Sgrò, C. Siskind, E.J. Spandre, G. Spinelli, P. Suson, D.J. Tajima, H. Thayer, J.B. Torres, D.F. Wang, Jian-Min Zhao, Zi-Hao Department of Physics and Astronomy Clemson University Kinard Lab of Physics ClemsonSC29634-0978 United States Instituto de Física Teórica UAM CSIC Universidad Autónoma de Madrid MadridE-28049 Spain Università di Pisa Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy Istituto Nazionale di Fisica Nucleare Sezione di Bari BariI-70126 Italy Università degli studi di Trento via Calepina 14 Trento38122 Italy Istituto Nazionale di Fisica Nucleare Sezione di Padova PadovaI-35131 Italy Dipartimento di Fisica e Astronomia "G. Galilei" Università di Padova Via F. Marzolo 8 PadovaI-35131 Italy Center for Space Studies and Activities "G. Colombo" University of Padova Via Venezia 15 PadovaI-35131 Italy Instituto de Astrofísica de Canarias Universidad de La Laguna Dpto. Astrofísica Tenerife La Laguna38200 Spain Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy California State University Los Angeles Department of Physics and Astronomy Los AngelesCA90032 United States Dipartimento di Fisica "M. Merlin" dell’Università e del Politecnico di Bari via Amendola 173 BariI-70126 Italy W. W. Hansen Experimental Physics Laboratory Kavli Institute for Particle Astrophysics and Cosmology Department of Physics SLAC National Accelerator Laboratory Stanford University StanfordCA94305 United States Istituto Nazionale di Fisica Nucleare Sezione di Torino TorinoI-10125 Italy Dipartimento di Fisica Università degli Studi di Torino TorinoI-10125 Italy Laboratoire Leprince-Ringuet CNRS IN2P3 École polytechnique Institut Polytechnique de Paris Palaiseau91120 France Institut für Theoretische Physik and Astrophysik Universität Würzburg WürzburgD-97074 Germany INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica Milano via E. Bassini 15 MilanoI-20133 Italy Italian Space Agency Via del Politecnico snc Roma00133 Italy Istituto Nazionale di Fisica Nucleare Sezione di Roma "Tor Vergata" RomaI-00133 Italy Space Sci

Relativistic jets around supermassive black holes (SMBHs) are well-known powerful γ-ray emitters. In absence of the jets in radio-quiet active galactic nuclei (AGNs), how the SMBHs work in γ-ray bands is still unknown despite of great observational efforts made in the last 3 decades. Considering the previous efforts, we carefully select an AGN sample composed of 37 nearby Seyfert galaxies with ultra-hard X-rays for the goals of γ-ray detections by excluding all potential contamination in this band. Adopting a stacking technique, here we report the significant γ-ray detection (TS = 30.6, or 5.2 σ) from the sample using 15-year Fermi-Large Area Telescope (LAT) observation. We find an average γ-ray luminosity of the sample as (1.5 ± 1.0) × 1040 erg s−1 at energies from 1-300 GeV. Limited by the well-known pair production from the interaction of γ-rays with low energy photons, several GeV γ-rays are found to originate from an extended corona (∼ 2.7 × 106Rg), whereas the canonical much more compact X-ray corona (∼ 10Rg) is responsible for 1 to several GeV γ-rays. The finding of the compact region lends to strong supports to the long-time theoretical expectations, but the extended corona is beyond all the existing models. One promising scenario is that the electron-positron pairs produced in the compact X-ray corona would expand as fireball, similar to that in γ-ray bursts, forming the structure of extended corona. © 2025, CC BY.

关键词： Active Galactic Nuclei

Adaptive spatial modulation for visible light communications with an arbitrary number of transmitters

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arXiv 2018年

作者： Wang, Jin-Yuan Ge, Hong Zhu, Jian-Xia Wang, Jun-Bo Dai, Jianxin Lin, Min Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210003 China National Mobile Communications Research Laboratory Southeast University Nanjing210096 China School of Science Nanjing University of Posts and Telecommunications Nanjing210003 China

As a power and bandwidth efficient modulation scheme, the optical spatial modulation (SM) technique has recently drawn increased attention in the field of visible light communications (VLC). To guarantee the number of bits mapped by the transmitter's index at each timeslot is an integer, the number of transmitters (i.e., light-emitting diodes) in the SM based VLC system is often set be a power of two. To break the limitation on the required number of transmitters and provide more design flexibility, this paper investigates the SM based VLC with an arbitrary number of transmitters. Initially, a channel adaptive bit mapping (CABM) scheme is proposed, which includes three steps: Bit mapping in space domain, bit mapping in signal domain, and the channel adaptive mapping. The proposed CABM scheme allows operation with an arbitrary number of transmitters, and is verified to be an efficient scheme through numerical results. Based on the CABM scheme, the information-theoretical aspects of the SM based VLC are analyzed. The theoretical expression of the mutual information is first analyzed. However, it is very hard to evaluate system performance. To obtain more insights, a lower bound of the mutual information is derived, which is in closedform. Both theoretical analysis and numerical results show that the gap between the mutual information and its lower bound is small. Finally, to further improve the system performance, the precoding scheme is proposed for the SM based VLC. Numerical results show that the system performance improves dramatically when using the proposed precoding scheme. Copyright © 2018, The Authors. All rights reserved.

关键词： Visible light communication

Quantum-to-quantum Bernoulli factory problem

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arXiv 2017年

作者： Jiang, Jiaqing Zhang, Jialin Sun, Xiaoming Cas Key Lab of Network Data Science and Technology Institute of Computing Technology Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Given a coin with unknown bias p ϵ [0,1], can we exactly simulate another coin with bias f(p)? The exact set of simulable functions has been well characterized 20 years ago. In this paper, we ask the quantum counterpart of this question: Given the quantum coin |p) = √p|0)+√1-p|1), can we exactly simulate another quantum coin |f(p)) =√f(p)|0)+√1-f(p)|1)? We give the full characterization of simulable quantum state k0(p)|0)+ k1(p)|1) from quantum coin |p) = √p|0)+ √1-p|1), and present an algorithm to transform it. Surprisingly, we show that simulable sets in the quantum-to-quantum case and classical-to-classical case have no inclusion relationship with each other. Copyright © 2017, The Authors. All rights reserved.

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Smoking and Risk of Colorectal Cancer Sub-classified by Tumor-infiltrating T Cells (vol 111, pg 42, 2019)

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JNCI-JOURNAL OF THE NATIONAL CANCER INSTITUTE 2019年第12期111卷 1365-1365页

作者： Hamada, Tsuyoshi Department of Oncologic Pathology Department of Medical Oncology Dana-Farber Cancer Institute and Harvard Medical School Boston MA Program in Molecular Pathological Epidemiology Department of Pathology Clinical and Translational Epidemiology Unit and Division of Gastroenterology Massachusetts General Hospital and Harvard Medical School Boston MA Department of Nutrition Division of Public Health Sciences Department of Surgery Washington University School of Medicine St. Louis MO Department of Epidemiology and Biostatistics and the Ministry of Education Key Lab of Environment and Health School of Public Health Huazhong University of Science and Technology Hubei P.R. China Department of Medical Oncology Chinese PLA General Hospital Beijing P.R. China College of Pharmacy Zhejiang Chinese Medical University Zhejiang P.R. China Department of Gastroenterology Rheumatology and Clinical Immunology Sapporo Medical University School of Medicine Sapporo Japan Department of Food Science and Biotechnology Dongguk University Goyang the Republic of Korea Department of Medicine and Channing Division of Network Medicine Broad Institute of MIT and Harvard Cambridge MA Department of Medicine Brigham and Women’s Hospital and Harvard Medical School Boston MA Department of Epidemiology Department of Biostatistics Harvard T.H. Chan School of Public Health Boston MA Yale Cancer Center New Haven CT Department of Medicine Yale School of Medicine New Haven CT Smilow Cancer Hospital New Haven CT

Evidence indicates not only carcinogenic effect of cigarette smoking but also its immunosuppressive effect. We hypothesized that the association of smoking with colorectal cancer risk might be stronger for tumors with lower anti-tumor adaptive immune response.;During follow-up of 134 981 participants (3 490 851 person-years) in the Nurses' Health Study and Health Professionals Follow-up Study, we documented 729 rectal and colon cancer cases with available data on T-cell densities in tumor microenvironment. Using the duplication-method Cox regression model, we examined a differential association of smoking status with risk of colorectal carcinoma subclassified by densities of CD3+ cells, CD8+ cells, CD45RO (PTPRC)+ cells, or FOXP3+ cells. All statistical tests were two-sided.;The association of smoking status with colorectal cancer risk differed by CD3+ cell density (Pheterogeneity = .007). Compared with never smokers, multivariable-adjusted hazard ratios for CD3+ cell-low colorectal cancer were 1.38 (95% confidence interval = 1.09 to 1.75) in former smokers and 1.59 (95% confidence interval = 1.14 to 2.23) in current smokers (Ptrend = .002, across smoking status categories). In contrast, smoking status was not associated with CD3+ cell-high cancer risk (Ptrend = .52). This differential association appeared consistent in strata of microsatellite instability, CpG island methylator phenotype, or BRAF mutation status. There was no statistically significant differential association according to densities of CD8+ cells, CD45RO+ cells, or FOXP3+ cells (Pheterogeneity > .04, with adjusted α of 0.01).;Colorectal cancer risk increased by smoking was stronger for tumors with lower T-lymphocyte response, suggesting an interplay of smoking and immunity in colorectal carcinogenesis.

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Local unitary classification for sets of generalized Bell states

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arXiv 2017年

作者： Wu, Bujiao Jiang, Jiaqing Zhang, Jialin Tian, Guojing Sun, Xiaoming CAS Key Lab of Network Data Science and Technology Institute of Computing Technology Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing100049 China

In this paper, we study the local unitary classification for pairs (triples) of generalized Bell states, based on the local unitary equivalence of two sets. In detail, we firstly introduce some general unitary operators which give us more local unitary equivalent sets besides Clifford operators. And then we present two necessary conditions for local unitary equivalent sets which can be used to examine the local inequivalence. Following this approach, we completely classify all of pairs in d ⊗ d quantum system into ∏nj=1(kj + 1) LU-inequivalent pairs when the prime factorization of d = ∏nj=1 pkjj . Moreover, all of triples in pα ⊗ pα quantum system for prime p can be partitioned into (α+3) 6 pα+O(αpα−1) LU-inequivalent triples, especially, when α = 2 and p > 2, there are exactly ⌊5/6 p2⌋ + ⌊p−2/6 + (−1)⌊ p/3⌋p/3 ⌋ + 3 LU-inequivalent triples. Copyright © 2017, The Authors. All rights reserved.

关键词： Quantum optics

Weighted community detection and data clustering using message passing

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arXiv 2018年

作者： Shi, Cheng Liu, Yanchen Zhang, Pan CompleX Lab Web Sciences Center University of Electronic Science and Technology of China Chengdu611731 China Network Science Institute Northeastern University 177 Huntington Avenue BostonMA02115 United States CAS key laboratory of theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing100190 China

Grouping objects into clusters based on similarities or weights between them is one of the most important problems in science and engineering. In this work, by extending message passing algorithms and spectral algorithms proposed for unweighted community detection problem, we develop a non-parametric method based on statistical physics, by mapping the problem to Potts model at the critical temperature of spin glass transition and applying belief propagation to solve the marginals corresponding to the Boltzmann distribution. Our algorithm is robust to over-fitting and gives a principled way to determine whether there are significant clusters in the data and how many clusters there are. We apply our method to different clustering tasks. In the community detection problem in weighted and directed networks, we show that our algorithm significantly outperforms existing algorithms. In the clustering problem when the data was generated by mixture models in the sparse regime we show that our method works all the way down to the theoretical limit of detectability and gives accuracy very close to that of the optimal Bayesian inference. In the semi-supervised clustering problem, our method only needs several labels to work perfectly in classic datasets. Finally, we further develop Thouless-Anderson-Palmer equations which reduce heavily the computation complexity in dense-networks but gives almost the same performance as belief propagation. Copyright © 2018, The Authors. All rights reserved.

关键词： Inference engines

The Fermi-LAT Light Curve Repository

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arXiv 2023年

作者： Abdollahi, S. Ajello, M. Baldini, L. Ballet, J. Bastieri, D. Gonzalez, J. Becerra Bellazzini, R. Berretta, A. Bissaldi, E. Bonino, R. Brill, A. Bruel, P. Burns, E. Buson, S. Cameron, R.A. Caputo, R. Caraveo, P.A. Cibrario, N. Ciprini, S. Orestano, P. Cristarella Crnogorcevic, M. Cutini, S. D’Ammando, F. De Gaetano, S. Digel, S.W. Di Lalla, N. Di Venere, L. Domínguez, A. Ramazani, V. Fallah Fegan, S.J. Ferrara, E.C. Fiori, A. Fleischhack, H. Franckowiak, A. Fukazawa, Y. Fusco, P. Gammaldi, V. Gargano, F. Garrappa, S. Gasbarra, C. Gasparrini, D. Giglietto, N. Giordano, F. Giroletti, M. Green, D. Grenier, I.A. Guiriec, S. Gustafsson, M. Hays, E. Horan, D. Hou, X. Jóhannesson, G. Kerr, M. Kocevski, D. Kuss, M. Latronico, L. Li, J. Liodakis, I. Longo, F. Loparco, F. Lorusso, L. Lott, B. Lovellette, M.N. Lubrano, P. Maldera, S. Manfreda, A. Martí-Devesa, G. Mazziotta, M.N. Mereu, I. Meyer, M. Michelson, P.F. Mizuno, T. Monzani, M.E. Morselli, A. Moskalenko, I.V. Negro, M. Omodei, N. Orlando, E. Ormes, J.F. Paneque, D. Panzarini, G. Perkins, J.S. Persic, M. Pesce-Rollins, M. Pillera, R. Porter, T.A. Principe, G. Racusin, J.L. Rainò, S. Rando, R. Rani, B. Razzano, M. Razzaque, S. Reimer, A. Reimer, O. Sánchez-Conde, M. Parkinson, P.M. Saz Scargle, Jeff Scotton, L. Serini, D. Sgrò, C. Siskind, E.J. Spandre, G. Spinelli, P. Suson, D.J. Tajima, H. Thompson, D.J. Torres, D.F. Valverde, J. Venters, T. Wadiasingh, Z. Wagner, S. Wood, K. IRAP Université de Toulouse CNRS UPS CNES ToulouseF-31028 France Department of Physics and Astronomy Clemson University Kinard Lab of Physics ClemsonSC29634-0978 United States Università di Pisa Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy Université Paris-Saclay Université Paris Cité CEA CNRS AIM Gif-sur-YvetteF-91191 Cedex France Istituto Nazionale di Fisica Nucleare Sezione di Padova PadovaI-35131 Italy Dipartimento di Fisica e Astronomia "G. Galilei" Università di Padova Via F. Marzolo 8 PadovaI-35131 Italy Center for Space Studies and Activities "G. Colombo" University of Padova Via Venezia 15 PadovaI-35131 Italy Instituto de Astrofísica de Canarias Observatorio del Teide C/Via Lactea s/n Tenerife La LagunaE-38205 Spain Istituto Nazionale di Fisica Nucleare Sezione di Pisa PisaI-56127 Italy Dipartimento di Fisica Università degli Studi di Perugia PerugiaI-06123 Italy Dipartimento di Fisica "M. Merlin" dell’Università e del Politecnico di Bari via Amendola 173 BariI-70126 Italy Istituto Nazionale di Fisica Nucleare Sezione di Bari BariI-70126 Italy Istituto Nazionale di Fisica Nucleare Sezione di Torino TorinoI-10125 Italy Dipartimento di Fisica Università degli Studi di Torino TorinoI-10125 Italy NASA Postdoctoral Program Fellow United States NASA Goddard Space Flight Center GreenbeltMD20771 United States Laboratoire Leprince-Ringuet CNRS IN2P3 École polytechnique Institut Polytechnique de Paris Palaiseau91120 France Department of physics and Astronomy Louisiana State University Baton RougeLA70803 United States Institut für Theoretische Physik and Astrophysik Universität Würzburg WürzburgD-97074 Germany W. W. Hansen Experimental Physics Laboratory Kavli Institute for Particle Astrophysics and Cosmology Department of Physics SLAC National Accelerator Laboratory Stanford University StanfordCA94305 United States INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica Milano via E. Bassi

The Fermi Large Area Telescope (LAT) light curve repository (LCR) is a publicly available, continually updated library of gamma-ray light curves of variable Fermi-LAT sources generated over multiple timescales. The Fermi-LAT LCR aims to provide publication-quality light curves binned on timescales of 3 days, 7 days, and 30 days for 1525 sources deemed variable in the source catalog of the first 10 years of Fermi-LAT observations. The repository consists of light curves generated through full likelihood analyses that model the sources and the surrounding region, providing fluxes and photon indices for each time bin. The LCR is intended as a resource for the time-domain and multi-messenger communities by allowing users to quickly search LAT data to identify correlated variability and flaring emission episodes from gamma-ray sources. We describe the sample selection and analysis employed by the LCR and provide an overview of the associated data access portal. Copyright © 2023, The Authors. All rights reserved.

关键词： Gamma rays

Visco-acoustic Wave-equation Traveltime Inversion with Correct and Incorrect Attenuation Profiles 87

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Visco-acoustic Wave-equation Traveltime Inversion with Corre...

Society of Exploration Geophysicists International Exposition and 87th Annual Meeting, SEG 2017

作者： Yu, Han Chen, Yuqing Guo, Bowen Schuster, Gerard T. Division of Physical Sciences and Engineering King Abdullah University of Science and Technology Thuwal23955-6900 Saudi Arabia Jiangsu Key Lab of Big Data Security and Intelligent Processing School of Computer Science Nanjing University of Posts and Telecommunications Nanjing210003 China

A visco-acoustic wave-equation traveltime inversion method is presented that inverts for a shallow subsurface velocity distribution with correct and incorrect attenuation profiles. Similar to the classical wave equation traveltime inversion, this method applies the misfit functional that minimizes the first break differences between the observed and predicted data. Although, WT can partly avoid the cycle skipping problem, an initial velocity model approaches to the right or wrong velocity models under different setups of the attenuation profiles. However, with a Q model far away from the real model, the inverted tomogram is obviously different from the true velocity model while a small change of the Q model does not improve the inversion quality in a strong manner if low frequency information is not lost.. © 2017 SEG.

关键词： Wave equations

An ensemble method for job recommender systems 10

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An ensemble method for job recommender systems

10th ACM Conference on Recommender Systems Challenge, RecSys Challenge 2016

作者： Zhang, Chenrui Cheng, Xueqi CAS Key Lab of Network Data Science and Technology Institute of Computing Technology Chinese Academy of Sciences Beijing China

ISBN: (纸本)9781450348010

In this paper, we present an ensemble method for job recommendation to ACM RecSys Challenge 2016. Given a user, the goal of a job recommendation system is to predict those job postings that are likely to be relevant to the user1. Firstly, we analyze the train dataset and find several interesting patterns. Secondly, we describe our solution, which is an ensemble of two filters, combining the merits of traditional collaborative filtering and content-based filtering. Our approach finally achieved a score of 1632828.82, ranked at the 10th place on the public leaderboard. © 2016 ACM.

关键词： Collaborative filtering