1. Measuring the Galactic Cosmic Ray Flux with the LISA Pathfinder Radiation Monitor
- Author
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A. Cesarini, G. Russano, Ignacio Mateos, Ivan Lloro, Daniele Bortoluzzi, L. Mendes, Peter Zweifel, Gerhard Heinzel, Miquel Nofrarías, Domenico Giardini, J. P. López-Zaragoza, A. Wittchen, Ferran Gibert, M. de Deus Silva, F. Martin-Porqueras, J. Reiche, Peter Wass, A. M. Cruise, N. Finetti, Davor Mance, Mauro Hueller, B. Kaune, N. Korsakova, D. Texier, Lluis Gesa, T. J. Sumner, L. Liu, G. Dixon, Oliver Jennrich, Catia Grimani, E. Castelli, S. Vitale, Michele Armano, R. Maarschalkerweerd, Ph. Jetzer, Pierre Binétruy, M. Freschi, Antoine Petiteau, Paul McNamara, Luigi Ferraioli, D. I. Robertson, Jacob Slutsky, Valerio Ferroni, E. Plagnol, James Ira Thorpe, Carlos F. Sopuerta, D. Hoyland, Karsten Danzmann, M. Born, L. Martin-Polo, Antonella Cavalleri, J. Grzymisch, Henri Inchauspe, Ingo Diepholz, V. Martín, J. Martino, Daniele Vetrugno, Nikolaos Karnesis, H. Ward, F. Rivas, L. Wissel, P. Pivato, Gudrun Wanner, Juan Ramos-Castro, I. Harrison, Michael Perreur-Lloyd, N. Meshskar, Christian J. Killow, José F. F. Mendes, M. Hewitson, W. J. Weber, R. Giusteri, Rita Dolesi, J. Baird, E. D. Fitzsimons, J. A. Lobo, S. Paczkowski, Daniel Hollington, Heather Audley, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universitat Politècnica de Catalunya. Departament d'Enginyeria Electrònica, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), AstroParticule et Cosmologie ( APC - UMR 7164 ), Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
- Subjects
Astrofísica ,Pathfinder ,Astrophysics::High Energy Astrophysical Phenomena ,Flux ,FOS: Physical sciences ,Cosmic ray ,Astrophysics ,Radiation ,01 natural sciences ,0202 Atomic, Molecular, Nuclear, Particle And Plasma Physics ,Charging ,GCR ,GEANT4 ,LISA ,Radiation Monitor ,Astronomy and Astrophysics ,0103 physical sciences ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,[ PHYS.PHYS.PHYS-INS-DET ] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Physics ,Spacecraft ,010308 nuclear & particles physics ,Gravitational wave ,business.industry ,Astronomy ,Nuclear & Particles Physics ,0201 Astronomical And Space Sciences ,Física::Astronomia i astrofísica [Àrees temàtiques de la UPC] ,Physics::Space Physics ,Heliospheric current sheet ,business ,Astrophysics - Instrumentation and Methods for Astrophysics ,Noise (radio) ,astro-ph.IM - Abstract
© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ Test mass charging caused by cosmic rays will be a significant source of acceleration noise for space-based gravitational wave detectors like LISA. Operating between December 2015 and July 2017, the technology demonstration mission LISA Pathfinder included a bespoke monitor to help characterise the relationship between test mass charging and the local radiation environment. The radiation monitor made in situ measurements of the cosmic ray flux while also providing information about its energy spectrum. We describe the monitor and present measurements which show a gradual 40% increase in count rate coinciding with the declining phase of the solar cycle. Modulations of up to 10% were also observed with periods of 13 and 26 days that are associated with co-rotating interaction regions and heliospheric current sheet crossings. These variations in the flux above the monitor detection threshold (¿˜¿70¿MeV) are shown to be coherent with measurements made by the IREM monitor on-board the Earth orbiting INTEGRAL spacecraft. Finally we use the measured deposited energy spectra, in combination with a GEANT4 model, to estimate the galactic cosmic ray differential energy spectrum over the course of the mission.
- Published
- 2017