Download presentation

Presentation is loading. Please wait.

Published byZion Gowland Modified about 1 year ago

1
RICE bounds on UHE Neutrino fluxes in the GZK Regime plus bounds on new physics Data from 2000 through 2004 confront models of the world (PRELIMINARY) Data from 2000 through 2004 confront models of the world (PRELIMINARY)

2
Outline What RICE is What the new data say Calculation of bounds on GZK fluxes Results Calculation of bounds on LSG Results Summary and Conclusions

3
16 co-authors from Kansas, Delaware, Canterbury, MIT 16 Radio Receivers 200mX200mX200m Array Between 100m and 300m UNDER THE ICE at the SOUTH POLE A great debt owed to AMANDA Radio Cherenkov Detection of Neutrinos

4
RICE data collected 2000 - 2004 by the Radio Ice Cherenkov Detector current RICE authors: Ilya Kravchenko,Dave Seckel, Jenni Adams, Steve Churchwell, Pauline Harris, Surujdeo Seunarine, Peter William, Alice Bean, Dave Besson *, Scott Graham, Sarah Holt, Shahid Hussain, Doug McKay, Josh Meyers, John Ralston, Rainer Schiel, Hanah Swift, *Contact: dzb@kuhep4.phsx.ku.edu

5
RICE Searches for UHE Cosmic Neutrino Hits in Antarctic Ice with Radio Antennas Coherent Cherenkov Pulses from Showers Pulses Amplified and Sent to Surface Trigger on 4 hits above Threshold* Triggered pulses Read into Oscilloscope, Saved Pulses are Time labeled - basis to reconstruct hits Acceptance of Above Summarized in V eff, the EFFECTIVE VOLUME *Background Fixes Discriminator Threshold

6
RICE Calibrations and Collateral Experiments Direct in situ attenuation length and refractive index in-ice measurements made by RICERS Antenna calibrations, gain calibrations, timing calibrations, vertexing tests, … are described in: I. Kravchenko et al., Astropart. Phys. 19, (2003) 15; Flux bounds and a recap of the calibrations and testing are presented in I Kravchenko et al., Astropart. Phys. 20, (2003) 195

7
Effective Volume Comments Landau, Pomeranchuk, Migdal effect (LPM) makes a difference only to EM showers Radio ray bending costs us effective volume. This feature is included here for the first time. Separate livetimes must be logged for each threshold setting, reflecting varying background conditions.

8
MC hit distribution with raytracing

9
Transmitter Location Reconstruction True (known) Transmitter Depth

10
RICE 2000-2004 ------ live-time Vs. discriminator threshold

13
Next RICE LIMITS ON COSMOGENIC FLUXES

14
Cosmogenic Fluxes, Comments: We choose a wide range of normalizations and several different forms of energy dependence to illustrate the corresponding range of rate expectations. Each of the cases shown is one out of a span of models (input parameter choices), that each group presents. The large is the largest one in the KKSS study, the medium is the smallest in the PJ study, and the small is the smallest in the ESS study. There is overlap among all of the groups.

15
After ~ 1.5 years livetime, what does RICE see? NO NEUTRINO EVENTS PASS FINAL CUTS - VERTEX LOCATION AND CONE FIT.

16
Rate Calculations and 95% CL Limits on Cosmogenic Neutrino Fluxes All neutrino flavors are included EM (electron neutrino only) and hadronic showers included, so CC and NC counted Improved Monte Carlos of V eff and offline cut efficiencies reduce nominal acceptance compared to 2000 and 2003 reports 2 years more data and lower ‘03 and -’04 backgrounds compensate {(Flux) bound = 3x(TxRate) -1 model x(Flux) model }* * @ 95%CL, where T is the livetime.

17
RICE 2000-2004 ---- SM bound on cosmogenic neutrino flux

18
Next: more limit calculations LOW SCALE GRAVITY: (LSG) limits on scale

19
Low Scale Gravity Cross Sections Need X- sections for BH production : with and without inelasticity (impact parameter effect) Need X-cross sections for KK -graviton exchange in eikonal (UNITARY) approximation Need shower rates from BH and KK-graviton (eikonal) AND from SM interactions for total rate All cross sections rise with energy, as does V eff, while the fluxes fall. Rates rely on X-section x Volume x Flux, and the product reveals the most sensitive energy range for a given detector.

20
CROSS SECTIONS PLOTS

22
Standard Model LSG, 1 TeV Scale LSG, 2 TeV Scale RICE 2000-2004 ---- ~ 1.5 years live-time Event Rates From Cosmogenic Neutrinos

23
RICE 2000-2004 ---- bounds on LSG from cosmogenic neutrinos

24
Summary RICE has completed a first analysis of all data from 2000 thru 2004 No neutrino candidates survive all cuts Preliminary bounds on representative - “small, medium and large” - GZK, or COSMOGENIC, flux models Bounds on Planck mass in 6-d low scale gravity models via elastic and BH production. Degeneracies confuse the interpretation of data.

25
RICE continues to determine the STRONGEST LIMITS for the energy range above about 10 18 eV

26
Conclusions the LARGEST cosmogenic flux model on the verge of 2-sigma EXCLUSION the INTERMEDIATE and SMALL FLUX models still 10 1 -10 1.5 below confrontation Depending on flux model and on low scale gravity model dependence, lower bounds on the Planck mass range from 1 to 10 TeV. Many Interpretations are possible. IT’S STILL EARLY IN THE GAME1

27
RICE 2000-2004 ---- volume with LPM effect

28
RICE 2000-2004 ---- volume without LPM effect

29
RICE ---- Volume versus Threshold

30
RICE 2000-2004 ---- SM bound on cosmosgenic neutrino flux RICE PRELIMINARY New Limit

31
1. Black holes without inelasticity CROSS SECTIONS

32
2. Black holes with inelasticity Cross sections continued…. Where,

33
Graviton exchange Cross sections continued….

34
Graviton exchange continued… Cross sections continued….

35
Showers from BHD Shower rates continued….

36
Showers from graviton exchange

Similar presentations

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google