D'AMMANDO, FILIPPOFILIPPOD'AMMANDO0000-0001-7618-7527Pucella, G.G.PucellaRAITERI, Claudia MariaClaudia MariaRAITERI0000-0003-1784-2784VILLATA, MassimoMassimoVILLATA0000-0003-1743-6946VITTORINI, VALERIOVALERIOVITTORINI0000-0002-1208-8818VERCELLONE, STEFANOSTEFANOVERCELLONE0000-0003-1163-1396Donnarumma, I.I.DonnarummaLongo, F.F.LongoTAVANI, MarcoMarcoTAVANI0000-0003-2893-1459ARGAN, ANDREAANDREAARGAN0000-0002-6230-665XBarbiellini, G.G.BarbielliniBoffelli, F.F.BoffelliBULGARELLI, ANDREAANDREABULGARELLI0000-0001-6347-0649CARAVEO, PATRIZIAPATRIZIACARAVEO0000-0003-2478-8018Cattaneo, P.W.P.W.CattaneoChen, A.W.A.W.ChenCocco, V.V.CoccoCOSTA, EliaEliaCOSTA0000-0002-9991-2709DEL MONTE, EttoreEttoreDEL MONTE0000-0002-3013-6334DE PARIS, GIACINTOGIACINTODE PARISDi Cocco, G.G.Di CoccoEVANGELISTA, YURIYURIEVANGELISTA0000-0001-6096-6710FEROCI, MARCOMARCOFEROCI0000-0002-7617-3421Ferrari, A.A.FerrariFIORINI, MAUROMAUROFIORINI0000-0001-8297-1983Froysland, T.T.FroyslandFUSCHINO, FABIOFABIOFUSCHINO0000-0003-2139-3299Galli, M.M.GalliGIANOTTI, FulvioFulvioGIANOTTI0000-0003-4666-119XGIULIANI, ANDREAANDREAGIULIANI0000-0002-4315-1699LABANTI, CLAUDIOCLAUDIOLABANTI0000-0002-5086-3619Lapshov, I.I.LapshovLAZZAROTTO, FRANCESCOFRANCESCOLAZZAROTTO0000-0003-4871-4072Lipari, P.P.LipariMARISALDI, MARTINOMARTINOMARISALDI0000-0002-4000-3789MEREGHETTI, SandroSandroMEREGHETTI0000-0003-3259-7801Morselli, A.A.MorselliPACCIANI, LUIGILUIGIPACCIANI0000-0001-6897-5996PELLIZZONI, ALBERTO PAOLOALBERTO PAOLOPELLIZZONI0000-0002-4590-0040Perotti, F.F.PerottiPIANO, GiovanniGiovanniPIANO0000-0002-9332-5319Picozza, P.P.PicozzaPILIA, MauraMauraPILIA0000-0001-7397-8091Prest, M.M.PrestRapisarda, M.M.RapisardaRappoldi, A.A.RappoldiSabatini, S.S.SabatiniSOFFITTA, PAOLOPAOLOSOFFITTA0000-0002-7781-4104TRIFOGLIO, MASSIMOMASSIMOTRIFOGLIO0000-0002-2505-3630TROIS, ALESSIOALESSIOTROIS0000-0002-3180-6002Vallazza, E.E.VallazzaZambra, A.A.ZambraZanello, D.D.ZanelloAgudo, I.I.AgudoAller, M.F.M.F.AllerAller, H.D.H.D.AllerArkharov, A.A.A.A.ArkharovBach, U.U.BachBenitez, E.E.BenitezBerdyugin, A.A.BerdyuginBlinov, D.A.D.A.BlinovBUEMI, CARLA SIMONACARLA SIMONABUEMI0000-0002-7288-4613Chen, W.P.W.P.ChenDI PAOLA, AndreaAndreaDI PAOLA0000-0002-2189-8644DI RICO, GianlucaGianlucaDI RICO0000-0002-5213-8269Dultzin, D.D.DultzinFuhrmann, L.L.FuhrmannGómez, J.L.J.L.GómezGurwell, M.A.M.A.GurwellJorstad, S.G.S.G.JorstadHeidt, J.J.HeidtHiriart, D.D.HiriartHsiao, H.Y.H.Y.HsiaoKimeridze, G.G.KimeridzeKonstantinova, T.S.T.S.KonstantinovaKopatskaya, E.N.E.N.KopatskayaKoptelova, E.E.KoptelovaKurtanidze, O.O.KurtanidzeLarionov, V.M.V.M.LarionovLETO, PAOLOPAOLOLETO0000-0003-4864-2806Lindfors, E.E.LindforsLopez, J.M.J.M.LopezMarscher, A.P.A.P.MarscherMcHardy, I.M.I.M.McHardyMelnichuk, D.A.D.A.MelnichukMommert, M.M.MommertMujica, R.R.MujicaNilsson, K.K.NilssonPasanen, M.M.PasanenRoca-Sogorb, M.M.Roca-SogorbSorcia, M.M.SorciaTakalo, L.O.L.O.TakaloTaylor, B.B.TaylorTRIGILIO, CORRADOCORRADOTRIGILIO0000-0002-1216-7831Troitsky, I.S.I.S.TroitskyUMANA, Grazia Maria GloriaGrazia Maria GloriaUMANA0000-0002-6972-8388ANTONELLI, Lucio AngeloLucio AngeloANTONELLI0000-0002-5037-9034Colafrancesco, S.S.ColafrancescoCutini, S.S.CutiniGasparrini, D.D.GasparriniPITTORI, CarlottaCarlottaPITTORI0000-0001-6661-9779Preger, B.B.PregerSantolamazza, P.P.SantolamazzaVERRECCHIA, FrancescoFrancescoVERRECCHIA0000-0003-3455-5082Giommi, P.P.GiommiSalotti, L.L.Salotti2023-01-242023-01-2420090004-6361http://hdl.handle.net/20.500.12386/33026We report the detection by the AGILE satellite of a rapid gamma-ray flare from the powerful gamma-ray quasar PKS 1510-089, during a pointing centered on the Galactic Center region from 1 March to 30 March 2008. This source has been continuosly monitored in the radio-to-optical bands by the GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT). Moreover, the gamma-ray flaring episode triggered three ToO observations by the Swift satellite in three consecutive days, starting from 20 March 2008. In the period 1-16 March 2008, AGILE detected gamma-ray emission from PKS 1510-089 at a significance level of 6.2-sigma with an average flux over the entire period of (84 +/- 17) x 10^{-8} photons cm^{-2} s^{-1} for photon energies above 100 MeV. After a predefined satellite re-pointing, between 17 and 21 March 2008, AGILE detected the source at a significance level of 7.3-sigma, with an average flux (E > 100 MeV) of (134 +/- 29) x 10^{-8} photons cm^{-2} s^{-1} and a peak level of (281 +/- 68) x 10^{-8} photons cm^{-2} s^{-1} with daily integration. During the observing period January-April 2008, the source also showed an intense and variable optical activity, with several flaring episodes and a significant increase of the flux was observed at millimetric frequencies. Moreover, in the X-ray band the Swift/XRT observations seem to show an harder-when-brighter behaviour of the source spectrum. The spectral energy distribution of mid-March 2008 is modelled with a homogeneous one-zone synchrotron self Compton emission plus contributions from inverse Compton scattering of external photons from both the accretion disc and the broad line region. Indeed, some features in the optical-UV spectrum seem to indicate the presence of Seyfert-like components, such as the little blue bump and the big blue bump.STAMPAenArticle10.1051/0004-6361/2009125602-s2.0-71849118769https://www.aanda.org/articles/aa/full_html/2009/46/aa12560-09/aa12560-09.htmlhttp://www.scopus.com/inward/record.url?eid=2-s2.0-71849118769&partnerID=MN8TOARS2009A&A...508..181DFIS/05 - ASTRONOMIA E ASTROFISICA