Institute of High Energy Physics, Beijing Working report (2013.9.1-2014.9.30) Miao He Institute of High Energy Physics, Beijing

Simulation & reconstruction Resume Experiences 1999.9-2003.7 Tsinghua University, Bachelor 2003.9-2008.7 IHEP, PhD 2008.7-2010.3 IHEP, Postdoc 2010.4-2010.12, IHEP, Assistant researcher 2011.1- , IHEP, Associate researcher Researches Simulation & reconstruction BESIII BEIIE-II This report Daya Bay Physics & offline JUNO Reconstruction MOMENT Physics and det 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2014/11/21

Daya Bay physics analysis Continue organizing physics analysis as the co-coordinator. Served in the Analysis Coordination Committee (ACC) since Jan 2013 Finished the oscillation analysis with full detector configuration. Organized the analysis of IHEP group (see detail in the next pages) Coordinated analysis comparison between different groups Pushed reactor flux and spectrum analysis. IHEP analysis group made significant contribution. Independent analysis of the absolute reactor flux. Independent analysis of the positron spectrum comparison between the measurement and the prediction. Independent analysis of the spectrum unfolding and the generic antineutrino spectrum. Other jobs of ACC such as organization of analysis workshops, review of conference talks and proceedings. 2014/11/21

Oscillation analysis Experiment overview First data analysis with the full detector configuration: 6 AD → 6+8 AD ×3.6 increase in total exposure by the end of 2013 Detector energy response and systematics Improvement in energy reconstruction and relative energy scale: 0.35% → 0.2% Improvement in absolute energy scale (nonlinearity): 1.5% → 0.7% Side-by-side comparison with two new ADs and re-evaluation of systematics Backgrounds Removal of AmC sources at far site. AmC rate is decreasing. 0.2 → 0.05 (per day) Model independent measurement of fast neutrons: 50% → ~22% Evaluation of the systematics of α-n θ13 analysis A pure relative pull χ2 analysis with quantitative evaluation of bias and sensitivity Study of time the dependence of reactor uncertainties: ~0.2σ effect Bold: new contribution from IHEP group 2014/11/21

Highlights in the oscillation analysis Improvement in the absolute energy model Model independent measurement of fast neutron background FADC measurement at IHEP/onsite LS measurement at IHEP RPC data was directly used in the analysis! Improvement in the fitter Improvement in the relative energy scale Impact of reactor time dependence on Δm2 Impact of reactor model constrain on sin22θ13 2014/11/21

Analysis results Improvement in θ13: 10% → 5.6% Improvement in m2ee: 8% → 4.5% Results were released in June 2014 Assigned as the co-editor of this paper. Being reviewed by the publication committee. Plan to submit it to PRL by the end of 2014. 2014/11/21

Daya Bay offline system In charge of budgeting and purchasing of offline equipment (supervised by Prof. LI Weidong and Prof. WANG Meng) Drafted the budget for the CAS operation funding (2014) and attended the review meeting in May 2014 Drafted the interim summary report (2013-2014) and the application form for the 973 funding (2015-2017) New computing resources in the past year: 200TB disk array, 400TB tape, 256 CPU cores In charge of offline software update and release Maintaining of the auto building and testing system Release NuWa-3.9.2: update simulation parameters Release NuWa-3.10.1: update energy reconstruction In charge of data production and management Maintaining of the keep-up data production Two physics production P13A/P14A, ~200,000 jobs, 240TB data volume One MC production Data storage: 100 TB on disk and 200 TB on tape per year Served as the offline on-call 2014/11/21

Event reconstruction in JUNO Defined reconstruction data model. Developed a preliminary algorithm of muon tracking in the JUNO central detector. Preliminary study on multiple muons (muon bundle) identification and short track reconstruction. Wrote the reconstruction part for CDR and the yellow book. Resolution of the track length Hit pattern of multiple muons 2014/11/21

MC study of CP-violation in MOMENT Worked as the co-convenor of the detector and physics working group of MOMENT: a muon-decay medium-baseline neutrino beam facility Signal rate calculation (IBD and inclusive charge current) Particle identification (investigation from other experiments) and background estimation e/μ misidentification -> background Charge misidentification -> background Neutral current -> π0 background Atmospheric background CP sensitivity study A χ2 fitting of the spectra distortion CP sensitivity, statistical only 2014/11/21

Publications Title Journal Author Comment 1 Spectral Measurement of Electron Antineutrino Oscillation Amplitude and Frequency at Daya Bay PRL 112, 061801 (2014) Daya Bay collaboration 2 Future Reactor Experiments NuFact2013 proceeding corresponding author 3 Performance quality monitoring system for the Daya Bay reactor neutrino experiment Chin. Phys. C 2014 38 (8): 086001 4 Muon-decay medium-baseline neutrino beam facility PhysRevSTAB.17.090101 Jun Cao, et al. Wrote physics and detector sections 5 Electron antineutrino disappearance with the full detector configuration at Daya Bay to be sub-mitted to PRL co-editor 2014/11/21

Conference talks Neutrino physics and prospective CPS:HEP Title conference Date Place Comment 1 Neutrino physics and prospective CPS:HEP 18-23 APR, 2014 Wuhan Plenary 2 Data processing and storage in the Daya Bay Reactor Antineutrino Experiment ICHEP2014 2-9 JUL, 2014 Valencia, Spain Parallel 3 Jiangmen Underground Neutrino Observatory NOW2014 7-14 SEP, 2014 Conca Specchiulla, Italy 2014/11/21

Fundings Title conference Date Place Comment 1 Study on massive neutrino properties with reactor antineutrinos in the Daya Bay and Daya Bay II experiment NSFC- RFBR (China-Russia) cooperation funding 90,000 RMB 2014-2015 Leader 2 Young scientist founding Chinese Academy of Sciences 400,000 RMB 2014-2017 3 Operation funding of the Daya Bay offline system 2,010,000 RMB 2014 Participant 2014/11/21

Working plans Continue physics analysis coordination in Daya Bay Reactor spectrum analysis Improvement of oscillation parameters Cosmogenic studies Operation and maintaining of the Daya Bay offline system JUNO R&D Study of the mixture PMT (20”+8”) approach: improve vertex and energy resolution; improve muon bundle identification Improve muon tracking Improve CP sensitivity study in MOMENT Number of signals Particle identification Atmospheric neutrino backgrounds New ideas 2014/11/21