Neutrinos @ HiRes

Kai MartensHigh Energy Astrophysics Institute

Department of Physics, University of Utah

HR1HR2

April 18, 2007 Kai Martens, University of Utah 2

The Experiment:

12.6 km apart

HR2: 12/199942 mirrors

3-31 elevation

DugwayProvingGrounds

HR1: 6/199719 mirrors

3-17elevation

Delta

HiRes on DPG:

April 18, 2007 Kai Martens, University of Utah 3

HiRes Optics:

Mirror surface 5.1 m2

Field of view: 16 x 14

Camera:16 x 16

PMTeach sees

1o x 1o

in sky

SUN:½o

UV filter !!!(protecting PMTs)

low resolutionhigh speed

April 18, 2007 Kai Martens, University of Utah 4

HiRes: Stereo!!!July 11, 1999; Energy: 19 EeV

Light Propagation:Atmosphere

April 18, 2007 Kai Martens, University of Utah 5

The Collaboration:S. BenZvi, J. Boyer, B. Connolly, C.B. Finley, B. Knapp, E.J. Mannel, A. O’Neill, M. Seman, S. Westerhoff

Columbia University

J.F. Amman, M.D. Cooper, C.M. Hoffman, M.H. Holzscheiter, C.A. Painter, J.S. Sarracino, G. Sinnis, T.N. Thompson, D. TupaLos Alamos National Laboratory

J. Belz, M. KirnUniversity of Montana

J.A.J. Matthews, M. RobertsUniversity of New Mexico

D.R. Bergman, G. Hughes, D. Ivanov, L. Perera, S.R. Schnetzer, L. Scott, S. Stratton, G.B. Thomson, A. ZechRutgers University

N. Manago, M. Sasaki

University of Tokyo

R.U. Abbasi, T. Abu-Zayyad, G. Archbold, K. Belov, Z. Cao, W. Deng, W. Hanlon, P. Huentemeyer, C.C.H. Jui, E.C. Loh, K. Martens,

J.N. Matthews, K. Reil, J. Smith, P. Sokolsky, R.W. Springer, B.T. Stokes, J.R. Thomas, S.B. Thomas, L. WienckeUniversity of Utah

Z. Cao, B. Zhang, Y. Zhang, Y. YangIHEP Bejing

April 18, 2007 Kai Martens, University of Utah 6

Highest Energy Cosmogenic

Graph by Semikoz + Sigl

April 18, 2007 Kai Martens, University of Utah 7

( Imagine ) a Mountain:

target masscalorimeter

shower

Daniele Fargion - or who’s idea was it?

April 18, 2007 Kai Martens, University of Utah 8

Tau Neutrinos ?pion decay:

+

e + e +

flavor counting: 2 + 1 e

neutrino oscillation:2 1 + 1

DELIVERABLES:1 e + 1 + 1

+ + 17% track

e + e + 18% shower hh + 65%

shower

April 18, 2007 Kai Martens, University of Utah 9

ANIS (by Gazizov & Kowalski, AMANDA)

But: made for detectors inside a spherical earth…(i.e. underground)

AllNeutrino InteractionSimulation

Incorporates: - cross sections: CC, NC, ee- (resonant)- () energy loss (parameterization)- decay tables- TAUOLA for -decay

weuse

April 18, 2007 Kai Martens, University of Utah 10

GTOPO 30 + ANIS:GTOPO30: 30 arcsec 1km

33 tiles; one boundary 22km south of our detectors…

April 18, 2007 Kai Martens, University of Utah 11

MC: Topology at WorkNeutrino interaction points (tau decay above ground):

Cedar Mtns

Deep Creek Rng

Stansbury Mtns Oquirrh Mtns

Fish Springs Rng Thomas Rng

Sheeprock Mtns

April 18, 2007 Kai Martens, University of Utah 12

Neutrino Injection:

Earth

HiRes:Impact Parameter

< 75km

Zenith:9010 deg

April 18, 2007 Kai Martens, University of Utah 13

Neutrinos: Zenith Angle > 90°

Cosmic Rays

MC input:

- triggered events- both detectors- MC generated geometries

Zenith is the discriminator!

Get geometry right !!!

up

shower axis

Cosmic Ray MC distorted:

too many high E

April 18, 2007 Kai Martens, University of Utah 14

Finding the good guysand keeping as many as possible!!! efficiency sensitivity

Review reconstruction: First step: SDP

SDP normal uncertainty:

April 18, 2007 Kai Martens, University of Utah 15

Event Geometry II: 2-dim 1-dim

in the SDP:

Rp

detector

shower

scanning range for Rp direction

2tan

cR

Tt ip0i

cut edge of Rp scanning range

April 18, 2007 Kai Martens, University of Utah 16

Curvature in the Timing Fit:

Rp

detector

shower

longitude =in plane angle

use ratio of tan(/2)and linear fit in longitude

April 18, 2007 Kai Martens, University of Utah 17

Well Reconstructed Events:ratio tan(/2) fit to linear fit

> 100

April 18, 2007 Kai Martens, University of Utah 18

Another Difference that Matters:

Rp

detector

shower

horizontal CR events: top of atmosphere large Rp

horizontal out of mountain:low in atmosphere small Rp

April 18, 2007 Kai Martens, University of Utah 19

Mapping out the lasers

SDP normalvector:

x-component

y-co

mpo

nent

April 18, 2007 Kai Martens, University of Utah 20

MC Reduction:ANIS: total of 494,440,080 towards HiRes

4297 trigger HR1, 2496 trigger HR2

MC survivors:Energy: ANIS input: HR1 HR2 stereo

1018 – 1019: 445,425,435 265 169 101019 – 1020: 44,558,618 97 38 111020 – 1021: 4,456,027 4 2 0

April 18, 2007 Kai Martens, University of Utah 21

Data Reduction: 152 neutrinos ???

some examples:

conclusion:all lasers!

April 18, 2007 Kai Martens, University of Utah 22

Flux Limit for Cosmogenic Neutrinos:

• Efficiency of HiRes to neutrino events from MC.• Zero events found.• Estimate upper limit with Poisson Statistics.• Cosmogenic Neutrino Flux: j(E) =E-2

Φ [ eV s-1 sr-1 cm-2]

max

min

E

E

2-3211 E)ATTT(N dE 32

HiRes-1 HiRes-2 Stereo

April 18, 2007 Kai Martens, University of Utah 23

The HiRes Tau Neutrino Limits:

Semikoz+Sigli,max

90% CL, units: eVcm-2 s-1 sr-1

(uncertainty MC statistics only)

1018 – 1019: 420 -20 +251019 – 1020: 1340 -110 +1401020 – 1021: 29400 -8900 +22100

Injection: E-2 spectrum

April 18, 2007 Kai Martens, University of Utah 24

(1200m above SL)

Interaction Length in Standard Rock:(Rock??? =2.65 g/cm3…)

Conclusion: NO upward going neutrinos @ 1018eV

(earth diameter)

Int,

April 18, 2007 Kai Martens, University of Utah 25

Interpretation of HiRes monocular CR:

Doug Bergman, Rutgers

Fits interpret spectrumin terms of

extragalactic protonsthat traveled from

cosmological sources

changed interpretation ofankle:

galactic/extragalactic transition: composition change vs. slope change

p+ (1232) +N

+

e + e +

April 18, 2007 Kai Martens, University of Utah 26

Some Input:

garbage in,

garbage out…

(this is MC!)