VERITAS status Stephan LeBohec and Brian Humensky for the VERITAS collaboration Adelaide, December 2006

Smithsonian Astrophysical Observatory * Smithsonian Astrophysical Observatory * Adler Planetarium Adler Planetarium Purdue University * Purdue University * Barnard College, NY Barnard College, NY Iowa State University * Iowa State University * DePauw University, IN DePauw University, IN Washington University, St. Louis * Washington University, St. Louis * Grinnell College, IA Grinnell College, IA University of Chicago * University of Chicago * University of California, Santa Cruz University of California, Santa Cruz University of Utah * University of Massachussetts University of Massachussetts University of California, Los Angeles * University of California, Los Angeles * Cork Institute of Technology Cork Institute of Technology McGill University, Montreal * McGill University, Montreal * Galway-Mayo Institute of Technology Galway-Mayo Institute of Technology National University of Ireland, Dublin * National University of Ireland, Dublin * National University of Ireland, Galway National University of Ireland, Galway University of Leeds * University of Leeds * Associate Members Associate Members Project office: Whipple observatory SAO VERITAS Collaboration ~65 members in more than 20 institutions Funding from NSF/DOE/Smithsonian/PPARC/SFI/NSERC

85 m 109 m 85 m 35 m T2 T1 T3 T4 Fall 2006 Since January 2006 January 2007

0.5 o 0.15 o pixel 340 Hexagonal Facets 0.60m across Davies-Cotton Diameter = 12m Focal Length = 12m Time dispersion < 5ns Bias alignment PSF FWHM 0.06 o

Light collecting cones to Increase light collection & shield from stray light 499 pixel camera 3.5 O FOV 0.15 O pixels Photonis XP2970 2x10 5 Gain Custom preamplifier installed in Base: 6.66 Effective Gain AC DC output for current monitoring Programmable test pulse input

Camera PMT Current monitor Charge Injection Telescope Electronics 500MHz Digitization 8(+3) bits 8  s deep memory x CFD Pattern Sensitive Trigger Readout 140ft 75  RG59 ~200m fiber Array Control Building Delays Array Trigger VERITAS ELECTRONICS

Telescope and Array Triggers Telescope: any 3 adjacent pixels within 10 ns Array: multiple telescope triggers within 100ns geometry telescope-delay (a tradition since March 2006). Trigger rate ~ 100 Hz Deadtime ~ 5 %

20ns/event 6ns frame every 2ns 85m 3.5 o

VERITAS OPtical Telescope Injection and Calibration System Pedestal Single photo-electron Raw data Time and gain corrected data

Rayleigh attenuation Rayleigh Scattering Rayleigh scattering based Absolute Calibration

7  /min 16.5  /hr 1/2 Two telescope stereo observation of the Crab Nebula

Mrk421: 5.6 gamma/minute over 7.2 hours Mrk501: 0.8 gamma/minute over 11.4 hours

Conclusions: * VERITAS FULLY OPERATIONAL IN 2007: Four 12m telescopes with 500 pixel cameras (3.5°) in southern Az (1800m) *SPECIFICATIONS: Energy threshold ~ 100GeV Angular resolution ~ 4'-6' Energy resolution~ 10-15% Collecting area~ 4×10 4 m 2 Crab rate~ 40/min

1996 First Proposal to Smithsonian (Buckley, Catanese, Weekes & Krennrich) 1998 VERITAS selected for internal support at SAO 1999 PPARC/EI approve funding for VERITAS 2000 Lehman review --> passed 2000 DOE funds VERITAS R&D 2000 VERITAS proposal to NSF/DOE --> NSF lacks funds 2001 Dec. 3 agencies appear ready to fund VERITAS --> OMB disapproves 2002 Decadel Survey by Nat. Academy --> endorses VERITAS 2003 Montosa canyon approved! --> lawsuit by environmental group decision to go to Kitt Peak instead! 2003 March VERITAS funded for 4 telescopes in U.S. by DoE & NSF! 2004 Feb. Prototype Telescope at testsite operational 2005 Feb. telescope 1 operational 2004 July site at Kitt Peak approved! 2005 Feb. infrastructure for VERITAS in place at Kitt Peak 2005 Tohono O’odham Nation files complaint --> site shutdown --> NSF volunteers to do a new EA --> resolution expected by Dec Fall Telescope 1 & 2 start FLWO basecamp 2006 Decision to built VERITAS-4 at basecamp + operate Dec. Kitt Peak site issue still unresolved …

1996 First Proposal to Smithsonian (Buckley, Catanese, Weekes & Krennrich) 1998 VERITAS selected for internal support at SAO 1999 PPARC/EI approve funding for VERITAS 2000 Lehman review --> passed 2000 DOE funds VERITAS R&D 2000 VERITAS proposal to NSF/DOE --> NSF lacks funds 2001 Dec. 3 agencies appear ready to fund VERITAS --> OMB disapproves 2002 Decadel Survey by Nat. Academy --> endorses VERITAS 2003 Montosa canyon approved! --> lawsuit by environmental group decision to go to Kitt Peak instead! 2003 March VERITAS funded for 4 telescopes in U.S. by DoE & NSF! 2004 Feb. Prototype Telescope at testsite operational 2005 Feb. telescope 1 operational 2004 July site at Kitt Peak approved! 2005 Feb. infrastructure for VERITAS in place at Kitt Peak 2005 Tohono O’odham Nation files complaint --> site shutdown --> NSF volunteers to do a new EA --> resolution expected by Dec Fall Telescope 1 & 2 start FLWO basecamp 2006 Decision to built VERITAS-4 at basecamp + operate Dec. Kitt Peak site issue still unresolved …

1996 First Proposal to Smithsonian (Buckley, Catanese, Weekes & Krennrich) 1998 VERITAS selected for internal support at SAO 1999 PPARC/EI approve funding for VERITAS 2000 Lehman review --> passed 2000 DOE funds VERITAS R&D 2000 VERITAS proposal to NSF/DOE --> NSF lacks funds 2001 Dec. 3 agencies appear ready to fund VERITAS --> OMB disapproves 2002 Decadel Survey by Nat. Academy --> endorses VERITAS 2003 Montosa canyon approved! --> lawsuit by environmental group decision to go to Kitt Peak instead! 2003 March VERITAS funded for 4 telescopes in U.S. by DoE & NSF! 2004 Feb. Prototype Telescope at testsite operational 2004 July site at Kitt Peak approved! 2005 Feb. telescope 1 operational 2005 Feb. infrastructure for VERITAS in place at Kitt Peak 2005 Tohono O’odham Nation files complaint --> site shutdown --> NSF volunteers to do a new EA --> resolution expected by Dec Fall Telescope 1 & 2 start FLWO basecamp 2006 Decision to built VERITAS-4 at basecamp + operate Dec. Kitt Peak site issue still unresolved …

1996 First Proposal to Smithsonian (Buckley, Catanese, Weekes & Krennrich) 1998 VERITAS selected for internal support at SAO 1999 PPARC/EI approve funding for VERITAS 2000 Lehman review --> passed 2000 DOE funds VERITAS R&D 2000 VERITAS proposal to NSF/DOE --> NSF lacks funds 2001 Dec. 3 agencies appear ready to fund VERITAS --> OMB disapproves 2002 Decadel Survey by Nat. Academy --> endorses VERITAS 2003 Montosa canyon approved! --> lawsuit by environmental group decision to go to Kitt Peak instead! 2003 March VERITAS funded for 4 telescopes in U.S. by DoE & NSF! 2004 Feb. Prototype Telescope at testsite operational 2004 July site at Kitt Peak approved! 2005 Feb. telescope 1 operational 2005 Feb. infrastructure for VERITAS in place at Kitt Peak 2005 Tohono O’odham Nation files complaint --> site shutdown --> NSF volunteers to do a new EA --> resolution expected by Dec Fall Telescope 1 & 2 start FLWO basecamp 2006 Decision to built VERITAS-4 at basecamp + operate Dec. Kitt Peak site issue still unresolved …

1996 First Proposal to Smithsonian (Buckley, Catanese, Weekes & Krennrich) 1998 VERITAS selected for internal support at SAO 1999 PPARC/EI approve funding for VERITAS 2000 Lehman review --> passed 2000 DOE funds VERITAS R&D 2000 VERITAS proposal to NSF/DOE --> NSF lacks funds 2001 Dec. 3 agencies appear ready to fund VERITAS --> OMB disapproves 2002 Decadel Survey by Nat. Academy --> endorses VERITAS 2003 Montosa canyon approved! --> lawsuit by environmental group decision to go to Kitt Peak instead! 2003 March VERITAS funded for 4 telescopes in U.S. by DoE & NSF! 2004 Feb. Prototype Telescope at testsite operational 2004 July site at Kitt Peak approved! 2005 Feb. telescope 1 operational 2005 Feb. infrastructure for VERITAS in place at Kitt Peak 2005 Tohono O’odham Nation files complaint --> site shutdown --> NSF volunteers to do a new EA --> resolution expected by Dec Fall Telescope 1 & 2 start FLWO basecamp 2006 Decision to built VERITAS-4 at basecamp + operate Dec. Kitt Peak site issue still unresolved …

NEAR FUTURE PLANS: Two year program at FLWO: 2007 & 2008 * Galactic plane sky survey * AGN search & monitoring, EBL studies * SNR, PWN searches and studies * Dark matter search * GRB follow-up Move in 2009 to permanent site at Kitt Peak