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Author Stoppa, F.; Bhattacharyya, S.; Ruiz de Austri, R.; Vreeswijk, P.; Caron, S.; Zaharijas, G.; Bloemen, S.; Principe, G.; Malyshev, D.; Vodeb, V.; Groot, P.J.; Cator, E.; Nelemans, G. url  doi
openurl 
  Title AutoSourceID-Classifier Star-galaxy classification using a convolutional neural network with spatial information Type Journal Article
  Year 2023 Publication (up) Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.  
  Volume 680 Issue Pages A109 - 16pp  
  Keywords methods: data analysis; techniques: image processing; astronomical databases: miscellaneous; stars: imaging; Galaxies: statistics  
  Abstract Aims. Traditional star-galaxy classification techniques often rely on feature estimation from catalogs, a process susceptible to introducing inaccuracies, thereby potentially jeopardizing the classification's reliability. Certain galaxies, especially those not manifesting as extended sources, can be misclassified when their shape parameters and flux solely drive the inference. We aim to create a robust and accurate classification network for identifying stars and galaxies directly from astronomical images.Methods. The AutoSourceID-Classifier (ASID-C) algorithm developed for this work uses 32x32 pixel single filter band source cutouts generated by the previously developed AutoSourceID-Light (ASID-L) code. By leveraging convolutional neural networks (CNN) and additional information about the source position within the full-field image, ASID-C aims to accurately classify all stars and galaxies within a survey. Subsequently, we employed a modified Platt scaling calibration for the output of the CNN, ensuring that the derived probabilities were effectively calibrated, delivering precise and reliable results.Results. We show that ASID-C, trained on MeerLICHT telescope images and using the Dark Energy Camera Legacy Survey (DECaLS) morphological classification, is a robust classifier and outperforms similar codes such as SourceExtractor. To facilitate a rigorous comparison, we also trained an eXtreme Gradient Boosting (XGBoost) model on tabular features extracted by SourceExtractor. While this XGBoost model approaches ASID-C in performance metrics, it does not offer the computational efficiency and reduced error propagation inherent in ASID-C's direct image-based classification approach. ASID-C excels in low signal-to-noise ratio and crowded scenarios, potentially aiding in transient host identification and advancing deep-sky astronomy.  
  Address [Stoppa, F.; Vreeswijk, P.; Bloemen, S.; Groot, P. J.; Nelemans, G.] Radboud Univ Nijmegen, Dept Astrophys IMAPP, POB 9010, NL-6500 GL Nijmegen, Netherlands, Email: f.stoppa@astro.ru.nl  
  Corporate Author Thesis  
  Publisher Edp Sciences S A Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0004-6361 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001131898100001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5888  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. url  doi
openurl 
  Title Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter Type Journal Article
  Year 2010 Publication (up) Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 34 Issue 5 Pages 314-326  
  Keywords Cosmic rays; UHECR; Anisotropy; Pierre Auger Observatory; Extra-galactic; GZK  
  Abstract Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, 6 x 10(19) eV. The anisotropy was measured by the fraction of arrival directions that are less than 3.1 degrees from the position of an active galactic nucleus within 75 Mpc (using the Veron-Cetty and Veron 12th catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (38(-6)(+7))%, compared with 21% expected for isotropic cosmic rays. This is down from the early estimate of (69-(+11)(13))%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.  
  Address [Allekotte, I.; Asorey, H.; Bertou, X.; Golup, G.; Gomez Berisso, M.; Harari, D.; Mollerach, S.; Ponce, V. H.; Roulet, E.] Ctr Atom Bariloche, San Carlos De Bariloche, Rio Negro, Argentina  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000284669100007 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 320  
Permanent link to this record
 

 
Author ANTARES Collaboration (Aguilar, J.A. et al); Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Salesa, F.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title Zenith distribution and flux of atmospheric muons measured with the 5-line ANTARES detector Type Journal Article
  Year 2010 Publication (up) Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 34 Issue 3 Pages 179-184  
  Keywords Atmospheric muons; Neutrino telescope; Depth-intensity relation  
  Abstract The ANTARES high-energy neutrino telescope is a three-dimensional array of about 900 photomultipliers distributed over 12 mooring lines installed in the Mediterranean Sea. Between February and November 2007 it acquired data in a 5-line configuration. The zenith angular distribution of the atmospheric muon flux and the associated depth-intensity relation are measured and compared with previous measurements and Monte Carlo expectations. An evaluation of the systematic effects due to uncertainties on environmental and detector parameters is presented.  
  Address [Bazzotti, M.; Biagi, S.; Carminati, G.; Giacomelli, G.; Margiotta, A.; Spurio, M.] Dipartimento Fis Univ, I-40127 Bologna, Italy, Email: Annarita.Margiotta@bo.infn.it  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000282496000005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 373  
Permanent link to this record
 

 
Author ANTARES Collaboration (Aguilar, J.A. et al); Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Salesa, F.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title A fast algorithm for muon track reconstruction and its application to the ANTARES neutrino telescope Type Journal Article
  Year 2011 Publication (up) Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 34 Issue 9 Pages 652-662  
  Keywords Neutrino telescope; Track reconstruction  
  Abstract An algorithm is presented, that provides a fast and robust reconstruction of neutrino induced upward-going muons and a discrimination of these events from downward-going atmospheric muon background in data collected by the ANTARES neutrino telescope. The algorithm consists of a hit merging and hit selection procedure followed by fitting steps for a track hypothesis and a point-like light source. It is particularly well-suited for real time applications such as online monitoring and fast triggering of optical follow-up observations for multi-messenger studies. The performance of the algorithm is evaluated with Monte Carlo simulations and various distributions are compared with that obtained in ANTARES data.  
  Address [Carminati, G.] Leiden Univ, NL-2300 RA Leiden, Netherlands, Email: brunner@ifh.de  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000289329100002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 608  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. url  doi
openurl 
  Title The exposure of the hybrid detector of the Pierre Auger Observatory Type Journal Article
  Year 2011 Publication (up) Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 34 Issue 6 Pages 368-381  
  Keywords Ultra high energy cosmic rays; Pierre Auger Observatory; Extensive air showers; Trigger; Exposure; Fluorescence detector; Hybrid  
  Abstract The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The “hybrid” detection mode combines the information from the two subsystems. We describe the determination of the hybrid exposure for events observed by the fluorescence telescopes in coincidence with at least one water-Cherenkov detector of the surface array. A detailed knowledge of the time dependence of the detection operations is crucial for an accurate evaluation of the exposure. We discuss the relevance of monitoring data collected during operations, such as the status of the fluorescence detector, background light and atmospheric conditions, that are used in both simulation and reconstruction.  
  Address [Ave, M.; Bluemer, H.; Daumiller, K.; Dembinski, H.; Engel, R.; Garrido, X.; Haungs, A.; Heck, D.; Huege, T.; Keilhauer, B.; Klages, H. O.; Kleinfeller, J.; Mathes, H. J.; Mueller, S.; Oehlschlaeger, J.; Pierog, T.; Roth, M.; Salamida, F.; Schieler, H.; Schroeder, F.; Schuessler, F.; Smida, R.; Ulrich, R.; Unger, M.; Valino, I.; Weinidl, A.; Will, M.; Wommer, M.] Karlsruhe Inst Technol, Inst Kernphys, Karlsruhe, Germany, Email: francesco.salamida@kit.edu  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000287068800007 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 580  
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