1 / 1

R eactor E xperiment for N eutrino O scillation Liquid Scintillator R&D

R eactor E xperiment for N eutrino O scillation Liquid Scintillator R&D JS Park for RENO Collaboration. Gd have large neutron capture cross section : ~49000 barn Gd needs to transform to Gd -CBX for loading into organic phase. pH 7.4. pH 5. Compton edge. Photo peak.

woody
Download Presentation

R eactor E xperiment for N eutrino O scillation Liquid Scintillator R&D

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Reactor Experiment for Neutrino Oscillation Liquid ScintillatorR&D JS Park for RENO Collaboration • Gd have large neutron capture • cross section : ~49000 barn • Gdneeds to transform to • Gd-CBX for loading into • organic phase pH 7.4 pH 5 Compton edge Photo peak MC simulation of internal background pH 6.5 pH 7.2 θ13 Dominant Reference - CsI Crystalwith3cm*3cm*3cm pH 7.5 pH 6.2 pH 9.7 pH 6.0 θ12 Dominant Introduction 20mL Liquid Scintillator • Theta 13 measuring Experiment • Two Identical Detectors : Lower Experimental errors : ~1% level !! • Power Reactors : 6-core • Large Volume Detector : 15 tons • Lower Background : Increase overburden • Detector Configuration • Reaction in the Detector 4-cylindrical detector Inverse Beta Decay Target : Gd-LS Catcher : LS Buffer : Mineral-Oil Veto : Water prompt signal Survival probability with respect to baseline(L) Near Detector Far Detector n ~30us P Gd Total E~8MeV Delayed signal Neutron captured byGadolinium Gd-CBX • Gd to Gd-CBX • Gd-CBX synthesis process • Quality check • We can check whether we truly make Gd-CBX power • with FT-IR Spectroscopy. • No OH group (3200~3500) • No free acid peak (~1700) • We have Carboxylic peak (~1420, ~1580) Reaction equation 1. RCOOH + NH3•H2O ->RCOONH4 + H2O 2. 3RCOONH4(aq) + GdCl3*6H2O -> Gd(RCOO)3 + 3NH4Cl After reaction pH Neutralization pH Gd-CBX precipitated !! Gd-CBX powder was rinsed with 18MΩ waterfor several times and dried in vacuumdesiccator. OH group Free acid peak • Gd-CBX powder for RENO Detector • Loading into LAB and purity • We can load Gd-CBX into LAB by 0.1% (1g/L). • ~ 95% of purity has been achieved. • Final Gd-CBX powder • After grinding, store in a petri dish No Free Acid Carboxylic peak No OH Group Liquid Scintillator • Required Properties • Fluor Optimization • Light Yield Measurement • Radioactive Background • Transparency • High light yield • Long term stability • High radiopurity • Safety matter • Reasonable price • Massive quantity available LY saturated when PPO 3g/L and bis-MSB 30mg/L Using Cs source : 0.662MeV Liquid Scintillator ingredients : Base solvent + primary scintillating fluor + secondary wavelength shifter • Internal background material : 238U, 232Th, 40K • PMT glass is dominant internal background material : ~10Hz • LS radioimpurity contribute to background : ~2Hz (10-12 g/g) PPO After Effect of wavelength shifter ICP-MS result of radioimpurity Before General Elements of Liquid Scintillator PMT sensitive region Bis-MSB Compton edge FT-IR Graph

More Related