The IceTop component of IceCube

1. The IceTop component of IceCube Perspective from the South Pole Tom Gaisser

2. Outline • Scientific goals • Design • IceTop sub-group: tasks and staffing • Budget & schedule Tom Gaisser

3. IceTop:the surface component of IceCube • A 3-dimensional air shower array for • Veto (i.e. tagging downward events) • Calibration • Primary composition from PeV to EeV • Calibration, composition analyses similar to SPASE-AMANDA but • 5000 x larger acceptance • wider energy range, better resolution • IceTop at high altitude (700 g/cm2) • 125 m spacing between IceTop stations • Ethreshold ~ 300 TeV for > 4 stations in coincidence • Useful rate to EeV Tom Gaisser

4. Showers triggering 4 stations give ~300 TeV threshold for EAS array Large showers with E ~ 100-1000 PeV will clarify transition from galactic to extra-galactic cosmic rays. Small showers (2-10 TeV) associated with the dominant m background in the deep detector are detected as 2-tank coincidences at a station. Detection efficiency ~ 5% provides large sample to study this background. Tom Gaisser

5. IceTop station schematic • Two Ice Tanks 3.1 m2 x 1 m deep (a la Haverah, Auger) • Coincidence between tanks = potential air shower • Signal in single tank = potential muon • Significant area for horizontal muons • Low Gain/High Gain operation to achieve dynamic range Tank simulation with GEANT-4 Tom Gaisser

6. IceTop tasks & activities • Design and construct tank detectors • Evenson, Shulman, McDermott, Roth, Stoyan, technician (TBH) • Deploy tanks • Gaisser, McDermott, Roth, technician (TBH) Yoshida (Chiba), student (UWRF), RPSC support, Engineer (SSEC) • Confirm dynamic range scheme for 2 DOMs • Bai • Calibrate detectors • Bai, Stoyan, Gaisser, Clem, Niessen, Spiczak (UWRF) • Develop and install DAQ firmware • Evenson, Seckel • Integrate DAQ software as part of IceCube • Seckel, Software engineer (TBH), Svarnkar (grad student), Asst Prof (TBH) • Simulations • Stanev, Niessen, Gaisser • Reconstruction, data handling • Tilav, Post-doc (TBH) • Physics analysis • All, including Asst Prof (TBH) Tom Gaisser

7. Staffing plans • Current • 9 months faculty salary (includes 1 month UWRF) • 10 months technical staff • 5 months engineer • 50 months research scientists/post-doctoral (includes SPASE, which becomes part of IceCube in PY3) • 12 months grad student • Additional for PY03-PY10 • 4 months faculty salary (new Asst Prof) • 12 months entry-level technician • 12 months software engineer • 12 months post-doc for event reconstruction • 12 months for second grad student Tom Gaisser

8. Budget • IceTop (1.3.2) is an integral part of IceCube • IceTop effort focused at Bartol/UD & UWRF • Air showers generate the primary background for IceCube as a neutrino telescope • Bartol/IceTop efforts (e.g. in simulation, DAQ, reconstruction, physics analysis) make substantial contributions to other WBS elements • 1.3.2 PY3: UD $1,086K; UWRF $60K; Total $1,146K • Other WBS elements in PY3: UD: $344K • Tank construction schedule: • 10+32 in PY3 then 32 each in PY4,5,6 then 22 in PY7 • This schedule allows shipping by vessel after PY3 Tom Gaisser

9. Outline of Bartol/UD budget PY3 LaborCapitalMaterial & Supplies (includes shipping) 1.2.3.3 Field season ops $38K $20K 1.3.2.1 Tanks (10 + 32) 84 $250K 30 1.3.2.2 Cables (local coin only) 22 20 3 1.3.2.3 DOMs (labor only) 28 1.3.2.4 IceTop specific engineering 328 120 1.3.2.5 Integration of SPASE 90 10 1.3.2.6 Management/office 101 1.3.4.5 Test DAQ System 36 1.3.4.6 First deployment DAQ 8 1.4.3.1 Event generation 39 10 1.4.3.3 Detector simulation 33 6 1.5.1 Detector verification 50 1.5.2.1 Reconstruction 78 1.5.3.2 Calibration 26 Totals 961 296 173 $1,436K Tom Gaisser