GLoBES Patrick Huber IPNAS, Virginia Tech International Neutrino Summer School Fermilab, July 6-17, 2009 P. Huber – p. 1
What? General Long Baseline Experiment Simulator GLoBES is a software package designed for • Simulation • Analysis • Comparison of neutrino oscillation experiments P. Huber – p. 2
Where? It is developed and maintained by • PH • Joachim Kopp • Manfred Lindner • Walter Winter URL – http://www.mpi-hd.mpg.de/lin/globes/ email – globes@mpi-hd.mpg.de P. Huber – p. 3
Why? Wide band beam Resolution δ CP vs Sin 2 2 θ 13 150 δ CP (deg.) 150 100 ν µ Running Only True value of ∆ CP 100 50 90 % C.L. 50 0 3 cntrs: STAT only STAT+10 % SYST 0 STAT+20 % SYST � 50 -50 � 100 -100 � 150 FNAL-HS 1290 km sin 2 2 θ ij (12,23,13) = 0.86/1.0/0.04, δ CP =45 o ∆ m ij2 (21,32) = 7.3e-5/2.5e-3 eV 2 -150 1 MW, 0.5 MT, 5e7 sec 10 � 3 10 � 2 10 � 1 0 0.02 0.04 0.06 0.08 0.1 0.12 True value of sin 2 2 Θ 13 Sin 2 2 θ 13 P. Huber – p. 4
Why? APS study Sensitivity reach in sin 2 2 Θ 13 sin 2 2 Θ 13 3000 km � 2 � sgn � � m 31 3000 km CP viol. sin 2 2 Θ 13 7500 km � 2 � sgn � � m 31 7500 km No sensitivity � CP viol. sin 2 2 Θ 13 7500 km � 2 � sgn � � m 31 3000 km CP viol. 10 � 5 10 � 4 10 � 3 10 � 2 10 � 1 sin 2 2 Θ 13 P. Huber – p. 5
Why? Fermilab’s Proton driver report 10 � 5 MINOS CNGS D � CHOOZ Ν� factories T2K 10 � 4 NO � A Reactor � II Superbeam upgrades sin 2 2 Θ 13 discovery reach � 3 Σ � NO � A � FPD 2 nd GenPDExp NuFact 10 � 3 Superbeams � Reactor exps 10 � 2 Branching point Conv. beams 10 � 1 CHOOZ � Solar excluded 10 0 2005 2010 2015 2020 2025 2030 Year P. Huber – p. 6
Why? White paper on reactor neutrinos Reactor-I Reactor-II BG in far detector 2 2 θ 13 sensitivity limit bin-to-bin error 5% 1% 0.5% -2 -2 10 10 sin 0 . 1 % no BG, no bin-to-bin error 2 2 3 3 4 4 5 5 10 10 10 10 10 10 10 10 luminosity [t GW y] P. Huber – p. 7
Why? CERN strategy group ! 35 P. Huber et al. P. Huber – p. 8
Why? ISS 1 0.8 SPL T2HK Fraction of ∆ CP WBB 0.6 NF BB 0.4 0.2 GLoBES 2006 0 10 � 5 10 � 4 10 � 3 10 � 2 10 � 1 True value of sin 2 2 Θ 13 P. Huber – p. 9
Why? Joint BNL-FNAL study group 10. � 1. sin 2 2 Θ 13 NO Ν A � WBB � LAr WBB � WC T2KK GLoBES 2006 sin 2 2 Θ 13 10. � 2. 10. � 3. sin 2 2 Θ 13 10. � 2. CPV 10. � 3. sin 2 2 Θ 13 10. � 2. CPV 10. � 3. sin 2 2 Θ 13 10. � 2. sgn � m 2 10. � 3. 0.5 1 2 5 10 20 50 100 exposure � Mt MW 10 7 s � P. Huber – p. 10
Reliability • Re-use of code, the more a code has been used in real world applications the less likely are severe bugs. • Extensive testing • Good documentation • Intuitive API with error checking P. Huber – p. 11
Reproducibility The information given in a publication or proposal is not sufficient to reproduce the sensitivity estimates. • General data storage and exchange format for the inputs ⇔ flexibility? • All implicit assumptions and approximations have to be documented, that includes the actual algorithms ⇔ accuracy of documentation? • Version control and archiving P. Huber – p. 12
Documentation Without good documentation, the best software is useless or will be after very short time (=memory decay constant of typical physicist). This is a general problem with legacy code! Document what you do – do what you document and make sure that the average user understands what is going on. Also documentation needs testing and debugging. P. Huber – p. 13
GLoBES history • development started 2004 – PH, M. Lindner, W. Winter • major effort went into documentation • first release August 2004 – version 2.0.0 • major bug fix release March 2005 version 2.0.11 • J. Kopp joined in July 2005 • January 2007 – version 3.0, addition of major features • 93 publications citing the GLoBES paper, creating a total of 1514 citations P. Huber – p. 14
Design considerations • GPL • C-library – very portable, easy to interface, numerically efficient • Unix style separation of functionality – freedom to design analysis and to use any graphics tools • Experiments are defined using AEDL – relatively complicated parser, transparent experiment definition • Pull approach for systematics – flexible and intuitive • Local minimization instead of grids – much faster P. Huber – p. 15
Features • Accurate treatment of systematical errors • Arbitrary matter profile & uncertainties • Arbitrary energy resolution function • Single and multiple experiment simulation • Simple χ 2 calculation • Inclusion of external input • Projection of χ 2 (minimization) • User-defined systematics, oscillation probability engine, priors • Full support for lists in AEDL • Interpolating functions in AEDL • . . . P. Huber – p. 16
Summary GLoBES • is the only open source software of its kind • has withstood the test of time (netx month, 5 years!) • is at the core of most strategy documents • completely in C • flexibility to deal with complex many detector setups and non-standard physics P. Huber – p. 17
Installation If you have Linux • Install GSL if you don’t have it already – ftp://ftp.gnu.org/gnu/gsl/ • Go to http://www.mpi-hd.mpg.de/lin/globes/downloads – download GLoBES • ./configure make sudo make install P. Huber – p. 18
Installation If you have a Mac • Install GSL if you don’t have it already – ftp://ftp.gnu.org/gnu/gsl/ • Download http://www.phys.vt.edu/ pahuber/globes- 3.1.3.tar.gz • unpack it and change into the directory created by this ./configure --disable-rpath --enable-no-binary=yes make make install P. Huber – p. 19
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