Assessing compatibility of direct detection data: haloindependent global likelihood analyses
Abstract
We present two different haloindependent methods to assess the compatibility of several direct dark matter detection data sets for a given dark matter model using a global likelihood consisting of at least one extended likelihood and an arbitrary number of Gaussian or Poisson likelihoods. In the first method we find the global best fit halo function (we prove that it is a unique piecewise constant function with a number of down steps smaller than or equal to a maximum number that we compute) and construct a twosided pointwise confidence band at any desired confidence level, which can then be compared with those derived from the extended likelihood alone to assess the joint compatibility of the data. In the second method we define a “constrained parameter goodnessoffit” test statistic, whose pvalue we then use to define a “plausibility region” (e.g. where p≥10%). For any halo function not entirely contained within the plausibility region, the level of compatibility of the data is very low (e.g. p<10%). We illustrate these methods by applying them to CDMSIISi and SuperCDMS data, assuming dark matter particles with elastic spinindependent isospinconserving interactions or exothermic spinindependent isospinviolating interactions.
 Authors:
 Department of Physics and Astronomy, UCLA,475 Portola Plaza, Los Angeles, CA 90095 (United States)
 CERN Theory Division,CH1211, Geneva 23 (Switzerland)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22572166
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 10; Other Information: PUBLISHERID: JCAP10(2016)029; OAI: oai:repo.scoap3.org:17559; ccby Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COMPATIBILITY; ISOSPIN; NONLUMINOUS MATTER; PARTICLE IDENTIFICATION; PARTICLE INTERACTIONS; SI SEMICONDUCTOR DETECTORS; SUPERSYMMETRY; UNDERGROUND FACILITIES; WIMPS
Citation Formats
Gelmini, Graciela B., Huh, JiHaeng, and Witte, Samuel J. Assessing compatibility of direct detection data: haloindependent global likelihood analyses. United States: N. p., 2016.
Web. doi:10.1088/14757516/2016/10/029.
Gelmini, Graciela B., Huh, JiHaeng, & Witte, Samuel J. Assessing compatibility of direct detection data: haloindependent global likelihood analyses. United States. doi:10.1088/14757516/2016/10/029.
Gelmini, Graciela B., Huh, JiHaeng, and Witte, Samuel J. Tue .
"Assessing compatibility of direct detection data: haloindependent global likelihood analyses". United States.
doi:10.1088/14757516/2016/10/029.
@article{osti_22572166,
title = {Assessing compatibility of direct detection data: haloindependent global likelihood analyses},
author = {Gelmini, Graciela B. and Huh, JiHaeng and Witte, Samuel J.},
abstractNote = {We present two different haloindependent methods to assess the compatibility of several direct dark matter detection data sets for a given dark matter model using a global likelihood consisting of at least one extended likelihood and an arbitrary number of Gaussian or Poisson likelihoods. In the first method we find the global best fit halo function (we prove that it is a unique piecewise constant function with a number of down steps smaller than or equal to a maximum number that we compute) and construct a twosided pointwise confidence band at any desired confidence level, which can then be compared with those derived from the extended likelihood alone to assess the joint compatibility of the data. In the second method we define a “constrained parameter goodnessoffit” test statistic, whose pvalue we then use to define a “plausibility region” (e.g. where p≥10%). For any halo function not entirely contained within the plausibility region, the level of compatibility of the data is very low (e.g. p<10%). We illustrate these methods by applying them to CDMSIISi and SuperCDMS data, assuming dark matter particles with elastic spinindependent isospinconserving interactions or exothermic spinindependent isospinviolating interactions.},
doi = {10.1088/14757516/2016/10/029},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 10,
volume = 2016,
place = {United States},
year = {Tue Oct 18 00:00:00 EDT 2016},
month = {Tue Oct 18 00:00:00 EDT 2016}
}

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