Neutrino Fishing Neutrino Fishing in the Bahamas in the Bahamas - - PowerPoint PPT Presentation

The AUTEC array as a The AUTEC array as a neutrino detector… neutrino detector…

Neutrino Fishing Neutrino Fishing in the Bahamas in the Bahamas

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 2

At different times work contributed by: Shaffique Adam†, Giorgio Gratta, Nikolai Lehtinen§, Justin Vandenbroucke$, Yue Zhao (Stanford University) T.Berger#, M.Buckingham (SCRIPPS, UC San Diego) (SCRIPPS, UC San Diego)

†Now at Cornell University §Now at University of Hawaii, Manoa $Now at UC Berkeley #Now at ???????

Many thanks to the US Navy and, in particular: Many thanks to the US Navy and, in particular: D.Belasco D.Belasco, J. Cecil, D. , J. Cecil, D. Deveau Deveau, , D.

• D. Kapolka

Kapolka, T. Kelly , T. Kelly-

• Bissonnette

Bissonnette

Study of Acoustic Ultra-high energy Neutrino Detection

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 3

An acoustic array in sea water is only sensitive to neutrinos (and showering muons) since the atmosphere stops all other species Merit: particle ID is automatic Liability: (probably*) insensitive to the bulk of events

*Assuming the bulk of events are protons

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 4

Look for an existing very large hydrophone array with lattice density and frequency response matching the needs of UHE neutrino detection This is non-trivial: most military arrays are built for surveillance (make sure enemy subs don’t come too close) So they are:

• sensitive at low frequency (~<100 Hz) because
• subs produce mainly low frequency noise
• high frequency noise does not propagate very far
• sparse (signals come from hundreds of km distance)
• very secret…

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 5

Atlantic Undersea Test and Evaluation Center

The largest USN high resolution, deep tracking array.

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 6

Tongue of the Ocean from space Tongue of the Ocean from space

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 7 AUTEC IN-WATER TRACKING AREAS

ANDROS ISLAND

SITE 2 SALVADOR CAY SITE 3 BIGWOOD CAY SITE 4 GOLDING CAY

TONGUE OF THE OCEAN

EXUMA SOUND

NEW PROVIDENCE

NASSAU

SITE 1/2 TRACKING AREA (120 sq. nmi) SITE 3/4 TRACKING AREA (500 sq. nmi) SITE 2 SITE 2 SITE 2 SITE 3 SITE 3 SITE 3 SITE 4 SITE 4 SITE 4 MAIN BASE MAIN BASE MAIN BASE WEAPONS RANGE NATO FORACS AND OCEAN HAUL DOWN FACILITY

76° 30´ 77° 30´ 77° 00´ 23° 30´ 24° 00´ 24° 30´ 25° 00´

Sheltered (islands and ~m deep shoals) Deep (~1.5 km) volume of water Tongue Of The Ocean Very little shipping traffic S e v e r a l h y d r

• p

h

• n

e a r r a y s 4 s h

• r

e s t a t i

• n

s

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 8

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 9

AUTEC Site 1 on Andros Island AUTEC Site 1 on Andros Island

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 10

Autec Autec Site 3 ( Site 3 (Bigwood Bigwood Cay) Cay)

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 11

Range is large, helicopter is the favorite transportation (but boat is cheaper)

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 12

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 13

1.53 km 1.57 km 1.52 km 1.51 km 1.56 km 1.50 km

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 14

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 15

~4.5 m

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 16

Autec Autec phones are a good match phones are a good match to the problem but their lattice to the problem but their lattice spacing in spacing in x,y x,y and z and z is too is too coarse to be optimal coarse to be optimal

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 17

Very simple setup for cosmic Very simple setup for cosmic-

• ray DAQ:

ray DAQ:

• 1.7 GHz Pentium IV

1.7 GHz Pentium IV

• Natl

Natl Inst sound card (digitize 7 channels at 179 Inst sound card (digitize 7 channels at 179 kS/s kS/s) )

• Trigger/digital filter coded in

Trigger/digital filter coded in LabView LabView

• 60 GB hot

60 GB hot-

• swappable FireWire drive shipped back

swappable FireWire drive shipped back and forth to ferry data and program upgrades and forth to ferry data and program upgrades External drive

Acquire 1 ms (179 Samples) for every event Acquire 1 ms (179 Samples) for every event Use adaptive threshold Use adaptive threshold

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 18

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 19

Overall 70% Overall 70% livetime livetime is easy to obtain is easy to obtain

• 16 months at

the array

• 208 days livetime
• 25M triggers
• 350GB data

Present arrangement with the US Navy is very straightforward:

• Our DAQ is connected to their analog front–end

via a multi-conductor cable

• During their tests they physically disconnect us

G.Gratta, AUTEC 1st Acoustic MiniWorkshop, Stanford, Sept 13-14, 03 20

Status: Status:

• Properties of the AUTEC array relevant for UHE neutrinos

Properties of the AUTEC array relevant for UHE neutrinos published in published in N.Lehtinen N.Lehtinen et al. et al. Astropart

• Astropart. Phys. 17 (2002) 279

. Phys. 17 (2002) 279

• Largest data

Largest data-

• set ever collected being analyzed,

set ever collected being analyzed, paper expected in the near future (see Justin’s talk) paper expected in the near future (see Justin’s talk)

Future plans:

• Equip entire array (~60 phones and 250 km3)
• Possibly use new array (slightly larger with

readout entirely at Site 1

• Improve adaptive threshold algorithm
• Introduce 2-level trigger, with online

coincidence detection

• GPS time in data stream
• Collaborators would be welcome !