We present global fits to the Large Volume Scenario (LVS) of string models using current indirect data. We use WMAP5 constraints on dark matter relic density, b-physics and electroweak observables as well as direct search constraints. Such data can be adequately fit by LVS, with the best-fit point for mu>0 having chi^2=13.6 for 8 degrees of freedom. The resulting constraints on parameter space are robust in that they do not depend much upon the prior, or upon whether one uses Bayesian or frequentist interpretations of the data. Sparticle masses are constrained to be well below the 1 TeV level, predicting early SUSY discovery at the LHC. We devise a method of quantifying which are the most important constraints. We find that the LEP2 Higgs mass constraint, the relic density of dark matter and the anomalous magnetic moment of the muon affect the fits to the strongest degree.
Bayesian Selection of sign(mu) within mSUGRA in Global Fits Including WMAP5 Results
我们研究的约束最小超对称标准模型(mSUGRA)的属性进行拟合更新的间接数据,包括遗迹密度推断从WMAP 5的暗物质。为了找到在何种程度上亩< 0 is disfavoured compared to mu >0,我们比较贝叶斯证据值为这些模型,我们直接获得,并具有良好的精度,从最近开发的多模态嵌套抽样(“多巢”)技术。我们发现了在mu < 0上mSUGRA的mu > 0分支的弱到中等的证据,并估计概率比为P(mu > 0)/P(mu < 0)= 6-61,这取决于所使用的先验度量和范围。因此,有积极的(但不是压倒性的)证据表明mSUGRA中mu > 0。MultiNest技术还提供参数和其他相关量(如超伙伴质量)的概率分布。我们探索我们的结果的选择上使用的先验测量的依赖性。我们还使用贝叶斯证据来量化mSUGRA参数推断之间的一致性,这些推断来自具有最大影响的约束:(g-2)_mu,BR(b -> s gamma)和冷暗物质(DM)遗迹密度Omega_{DM} h ^2。
Determination of Nuclear PDFs using Markov Chain Monte Carlo Methods
Institute of Nuclear Physics Polish Academy of Sciences(波兰科学院核物理研究所);Southern Methodist University(南方卫理公会大学);Jefferson Lab(杰斐逊实验室);Westfälische Wilhelms-Universität Münster(明斯特西法利亚威廉大学)
Naturalness Priors and Fits to the Constrained Minimal Supersymmetric Standard Model
我们研究的效果,有利于低值的微调贝叶斯多维拟合的约束最小超对称标准模型(CMSSM或mSUGRA)当前数据的先验。暗物质遗迹密度、μ子的反常磁矩和b->s γ的分支比都被用来通过马尔可夫链蒙特卡罗采样器约束模型。由于自然性先验,后验概率分布偏向于较轻的希格斯粒子和超粒子质量,这种效应在高吉诺区最为明显。有趣的是,slepton质量是一个例外,偏向于更重的质量。对于最新的测量组合m_t=172.7+/-2.9 GeV,如果我们允许在预测其质量m_{h^0}时存在理论误差,那么在2 σ水平上最轻的CP偶希格斯h^0极区域是允许的。m_{h^0}在95% C. L.处被限制为小于120 GeV。探测B_s->mu^+ mu^-的分支比到2 x 10^{-8}的水平,就像Tevatron实验可能达到的那样,将覆盖32%的概率密度,而不管使用两个先验中的哪一个。
Institut de Física Corpuscular (IFIC), Consejo Superior de Investigaciones Científicas (CSIC) and Universitat de València (UV)(粒子物理研究所(IFIC),西班牙国家科学研究委员会(CSIC)和瓦伦西亚大学(UV));University of Basel(巴塞尔大学)
Lecture notes on Machine Learning applications for global fits
Dipartimento di Fisica e Astronomia “Galileo Galilei”, Università degli Studi di Padova and INFN Sezione Padova(帕多瓦大学伽利略·伽利莱物理与天文系及意大利国家核物理研究院帕多瓦分部);Centro de Astropartículas y Física de Altas Energías (CAPA)(高能天体物理与高能物理中心(CAPA))