# Presentation: 089286

##  HERON: Projected precision & plans

***             ******Real time***
***PP & ******7******Be solar ************ flux studies***

*********x ******+ e ************ ************x ******+ e****** ***

***Meat:  Test stellar models by PP luminosity in ************’s***

***Gravy: > Improve knowledge of sin******2****** Θ******12 ******, Θ******13***
***                   ******> Test  MSW-LMA  P******ee******(E************)***
***             ******> ‘MaVan’; other new physics ( e.g., ******************)?***

***R. E Lanou @Santa Fe***

***Requires unprecedented control of systematics (< 1 - 3%)***
***                                  ******& large samples***

## 

***Total Helium mass 22 tonnes at 50mK.***
*** ******No internal backgnd (superfluid self-cleaning).***
*** ******Scintillation/rotons  or****** Scintillation/e-bubbles******.***
***             ******(complement & redundancy)***
*** ******Scintillation: 35% of E******e****** into 16 eV UV   ***
***            ******( ************Rayl.****** > 200 meter; self-transparent ).***
*** ******Detection:2400wafer calorimeters above liquid.***
*** ******Event location: coded aperture array; few cm.).***
*** ******Fiducial volume variable:  ***
***     ******2.5 evts/(day-tonne)  LMA (pp+Be)  E******e****** > 45 keV .***
*** ******Helium immune to muon spallation/capture.***
*** ******External gamma backgrounds control : ***
***           ******Deep site & Shielding***
***           ******Material select + moderator ******solid N******2***
***          ******Gamma physics in Helium ************ n-Comptons***
***          ******Event signature (coded aperture)***
***          ******Fiducial cuts***

******

***R. E Lanou @Santa Fe***

## CRYOSTAT & MODERATOR

***Inner copper cryostat***

***Solid N******2 ******in acrylic moderator cells***

***Helium fiducial***
***& non-fiducial***
***volumes***

***Coded aperture***
***wafer array***

***CRYOSTAT & MODERATOR***

***R. E Lanou @Santa Fe***

## Estimating precision for flux measurement

***Role of coded aperture:***
***  ******Distinguishes point sources from distributed sources by likelihood***
***                ******(******scintillation photons pattern****** & no. of drifted ******recoil e-bubble******)***
***    ******Measures ******event energy****** calorimetrically (******photons******) ***
***    ******Measures point source ******position****** accurately***
***               ******(******photons****** with cruder check from ******e-bubble******) ***

***Quantities for extended LL separation of bckgnd, pp & Be:***
***                      ******Energy spectra ( ******E****** )***
***                      ***
***                      ******Event spatial distributions ( ******Z******, ******R******2****** )***
***                      ******Point-like source quality factors ( ******LL******, ******“ddL”****** ******(norm. LL)******)***
***                      ******Restriction of number drifted e’s detected ( ******“<3 over 5 keV”****** )***

***R. E Lanou @Santa Fe***

## Resolutions: 

***R. E Lanou @Santa Fe***

_***Resolutions (sigma)  for E***__***e***__*** > 45 keV***__**   **_
_**           **__**In fid. vol**__**.                  **__**60 cm beyond fid. vol**__**.**_**           **
**X                ****1.62 cm****                         ****2.1 cm**
**Y                ****1.54 cm****                         ****1.7 cm**
**Z                ****2.46 cm****                ****0.4 cm (top), 6.0 cm (bott.)**
**   **

***Energy***

***Spatial***

***“******Standard” fiducial vol. (54 m******3******):****** R < 250 cm;   -187.5 < Z < 87.5 cm***

## High level cuts (Erecoil>45keV; R2; Z; ne<3)

***Need to construct pdf’s and understand possible correlations ***

***R. E Lanou @Santa Fe***

***“******Standard” (8T)***

***“******Large” (11T)***

***High level cuts (% bckgnd remain )***
***    ******> N******e(5keV)****** < 3     ************  33.3 %***
***    ******> E******fit****** > 45 keV  ************  17.1 %***
***    ******> Std. Fid.        ************    1.25%***

## Simulating multi-year experiments

***Major computational task:***
***  ******> GEANT simulation of radioactive chains through detector.***
***           ******(U/Th, K, cosmogenics from cryostat, acrylic, nitrogen***
***             ******with activities from ************ , SNO, KamLAND )***

*** ******> Full coded aperture******-******based reconstruction of all events in He.***

***>To save computation time: analytic methods as much as possible.***
***    ******( 4.5 years-equivalent of backgrounds)***

*** ******> Evaluate later small non-analytic effects ******(UV multiple reflections )***

***> Construct p.d.f.’s of measured variables ( ******E, R******2******, Z, LL, DDL****** )***

*** ******> Create large pool of bckgnd, pp & Be for creating “data” mixes***
***   ******to test signal extraction procedures.***

***R. E Lanou @Santa Fe***

***(Y.H. Huang)***

## Available PDF’s

** ****(**** ****7****Be --****   ****Bckgnd --****   ****PP -- ****)**

***R. E Lanou @Santa Fe***

**R****2**

**Z**

**DDL ****(norm. C.A.)**

**E**

**LL ****(raw C.A.)**

## extLL = - ( Npp + NBe + NBkg  ) +  ln( NppPpp(vj) + NBePBe(vj) + NBkgPBkg(vj) )

***            ******and two different fiducial volumes.***

***R. E Lanou @Santa Fe***

*** ******Apply extended-LL method for 8 tonne and 11 tonne:***
***extLL = - ( N******pp****** + N******Be****** + N******Bkg******  ) + ************ ******ln( N******pp******P******pp******(v******j******) + N******Be******P******Be******(v******j******) + N******Bkg******P******Bkg******(v******j******) )***
***                                                  ******( P(v******j******) are pdf’s for either v******j****** = E, LL, R******2******, Z or ddL)****** ***

***j***

*** ******Data rates:****** ***
***      ******Signal:  PP=1.85  Be=0.64 events/day-tonne ***
***                      ******for ************m******2************7.9x10 ******-5************eV******2****** sin******2****** ************12 ************0.31 ***
***      ******Background: 5.16 events/day-tonne***

***Procedures for flux extraction:***

## HERON     Error Budget(s)

***HERON******     Error Budget(s)***

***R. E Lanou @Santa Fe***

- EVENTS:  1350          467      3769         5400      1868       15076      27000      9340      75380

*** ******Provides independent channels to PP, Be (& ************total******)************flux with high precision.***
*** ******Check:  Independent of fiducial volume over range of volumes.***

## Comparison of different size fiducial volumes:

***Comparison of different size fiducial volumes:***

***R. E Lanou @Santa Fe***

***PP***

***7******Be***

***tot. nu***

## Modulation

***Modulation***
***by***
***eccentricity***
***of annual***
***Solar orbit ***
***(1000 simulations***
***Bckgnd, pp & Be)***

***Eccentricity***
***(1000 simul.)***

***Chi-sqr/DF***
***(1000 simul.)***

***Single 5-yr***

***Single 5-yr***

***R. E Lanou @Santa Fe***

***1.67***

## Summary, Plans and Conclusions:

***Summary, Plans and Conclusions:***

*** ******Still need to wrap-up experiments on e-bubbles; further simulation details.***

***      ******On basis of prototype experiments & simulations predict ***
***    ******performance  sufficient to measure PP flux to <1.5% , ******7******Be to <4%***
***    ******and meet other physics goals if full scale HERON were to be built.***

*** ***_***Essential – and major – next step: Engineer & build a large scale prototype***_***.***
***  ******Need to know if superfluid design of this type can be built & costed.***
*** ******Scale version a cryogenic engineering task of significant complexity & cost.***
*** ******Not within the capability of university groups alone.***

*** ******Community has very exciting future program in ************ physics:***
*** ******Attested by long list of particle/nuclear topics, priorities, $$’s.***
*** ******Presently, testing the solar model with ************’s a very tough sell.***

*** ******Our decision, reluctantly:  ***
*** ******Do not pursue the large scale prototype at this time.   ***
*** ******Wrap-up present experiments.***
*** ******Mothball the project and archive.***

***Very good documentation: >20 publications, 7 PhD theses on physics processes***

## Supplemental slides

***on HERON not covered in this talk***

***R. E Lanou @Santa Fe***

## H. Eguchi, Y.H. Huang, Y.H. Kim, R.E. Lanou H.J. Maris, A.N. Mocharnuck, G.M. Seidel, B. Sethumadhavan and W. Yao  

**H. Eguchi, Y.H. Huang, Y.H. Kim, R.E. Lanou H.J. Maris, A.N. Mocharnuck, G.M. Seidel, B. Sethumadhavan and W. Yao****  **
**Department of Physics, Brown University**

**C. Enss, A. Fleischmann and J. Schonefeld**
**Kirchhoff Institut, Universitat Heidelberg**

**S.R. Bandler ****(NASA-Goddard)**** and S. Romaine ****(CfA-Harvard)****  **

**With collaboration on wafer calorimetry by:**

**With collaboration on engineering & computation on simulations :**
**                          ****K.T. Lesko and A.W. Poon**** **
**             ****Lawrence Berkeley National Laboratory**

## 10

**10**

**10**

**WATER CAVITY**

**N****2**** CRYOSTAT**

**INNER CRYOSTAT**

**ROCK**

**ROCK**

**ROCK**

**ROCK**

**ROCK**

**14**

**8**

**6**

**Plan View**

**Elevation**

**40**

**Storage for He(140kl) & N****2****(186kl)**** **

**DIMENSIONS IN METERS**

**Sketch of possible space configuration for HERON  (6000mwe)**

**Control room & electronics**

**  ****Detector constructed in situ.**
**  ****Cavity clean room status in assembly.**

**Aux. Equip. & gas panels**

**DRIFT**

**DRIFT**

**Liquefiers, pumps & aux. power**

***R. E Lanou @Santa Fe***

## Slide 17

## WAFER SENSITIVITY ( single 16 eV photons and e-bubble/phonons)

**Progress on metallic magnetic sensors for use on wafers:**
**MMS’s were developed at Brown and Heidelberg for astrophysics.**
**New results from Heidelberg collaborators.**

**New world record**
** ****3.4 eV**
**for energy dispersive **
**resolution.**

**Last year at LowNu-III**
**           ****(9.6 eV)**

**April ‘03**

**(Implications for a **
**CNO expt. with ****7****Li)**

## Progress on scaling up to heat capacity of full scale wafers:

**Prototype mass scale-up expt,**

_**At LowNu-III**_**:**
**Expt. to measure physics quantities for scale-up**
**Energy transfer processes                                   **
**      ****(electron-phonon, athermal/thermal, Kapitiza)**
**Relative heat capacities**
**Thermal links time constants**

##  Unusual but well established properties of e – in liquid 4He 

*** ******Unusual but well established properties of e****** –****** in liquid ******4******He ***
***                          ******( Sanders, Reif, Packard, Donnelly, Rayfield, Williams, Landau, Fetter ----  )***

***  ******Stopped e ******-  ******trapped in “bubble”-void:***

*** ******Pauli principle;  high zero point energy ( 1 eV ).***
***R ~ 18 ******Å***
*** ******~500 He atoms displaced.   F = M************* a***
*** ******M******* ****** ~ 243 m******He******   ************  ******a = +2g !***
*** ******If un-impeded would rise to surface ala “anti- free-fall”.***
*** ******Held at free surface by image charge potential unless released.***

*** ******Thermal phonons, ******3******He limit attainable velocity.  v(T).***
*** ******In superfluid, vortex generation limits to < 40 m/s.***
*** ******Modest electric fields can control velocity and release charges at surface.***

*** ******Some considerations on velocities & releasing:***

*** ******What is the fate of the recoil electron in the superfluid & can we use it?***

*** ****** ******Can we make use of this and why would we want to? ***

***  ******Use in conjunction with scintillation fast trigger and event signature.***
***  ******e ******–****** from ************ event in single wafer   vs.  multi-wafer for distributed Compton bckgnds******.***
***  ******Time delay & wafer hits give redundant position info.***
***  ******e ******– ******signal can be made larger than roton signal. A comparison of alternatives.***

## from B. Sethumadhavan poster

***from B. Sethumadhavan poster***

## from B. Sethumadhavan poster

***from B. Sethumadhavan poster***

## From Y.H. Huang seminar

***From Y.H. Huang seminar***

## From Y.H. Huang seminar

***From Y.H. Huang seminar***

## R. E Lanou @Santa Fe

***R. E Lanou @Santa Fe***