SEGRETO, ALBERTOALBERTOSEGRETO0000-0001-7341-6603MACCARONE, MARIA CONCETTAMARIA CONCETTAMACCARONE0000-0001-8722-0361CATALANO, OSVALDOOSVALDOCATALANO0000-0002-9554-4128Biondo, B.B.BiondoGARGANO, CarmeloCarmeloGARGANO0000-0002-0730-1899LA ROSA, GIOVANNIGIOVANNILA ROSA0000-0002-3931-2269RUSSO, FedericoFedericoRUSSO0000-0002-3476-0839SOTTILE, GiuseppeGiuseppeSOTTILE0000-0003-3101-3966FIORINI, MAUROMAUROFIORINI0000-0001-8297-1983INCORVAIA, SALVATORESALVATOREINCORVAIA0000-0003-4533-1703TOSO, GiorgioGiorgioTOSO0000-0002-9472-09002020-06-162020-06-162016978151060191897815106019250277-786Xhttp://hdl.handle.net/20.500.12386/26084ASTRI is the end-to-end prototype for the CTA small-size class of telescopes in a dual-mirror configuration (SST-2M) proposed by the Italian National Institute of Astrophysics (INAF) in the framework of the Cherenkov Telescope Array. ASTRI SST-2M has been installed at the Serra La Nave Astrophysical Observatory on Mount Etna (Sicily) and its Performance Verification Phase will start in autumn 2016. For the relative pixel calibration and gain monitoring, the ASTRI SST-2M camera is equipped with an internal illumination device, while an external, portable, illumination system, placed at a few km distance from the telescope, will be used for the absolute end-to-end calibration of the telescope spectral response. Moreover analysis of signals induced in the camera pixels by the night sky background (diffuse emission and reference stars) will be used to monitor the long term evolution of the telescope calibration. We present an overview of the ASTRI SST-2M absolute calibration strategy and the external illuminating device that will be used for its spectral calibrationSTAMPAenConference paper10.1117/12.22319222-s2.0-85000916518000387731100115https://www.spiedigitallibrary.org/conference-proceedings-of-spie/9906/1/The-absolute-calibration-strategy-of-the-ASTRI-SST-2M-telescope/10.1117/12.2231922.full2016SPIE.9906E..3SSFIS/05 - ASTRONOMIA E ASTROFISICA