Records |
Author |
Cabrera, M.E.; Casas, J.A.; Ruiz de Austri, R. |
Title |
MSSM forecast for the LHC |
Type |
Journal Article |
Year |
2010 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
05 |
Issue |
5 |
Pages |
043 - 48pp |
Keywords |
Beyond Standard Model; Supersymmetric Effective Theories |
Abstract |
We perform a forecast of the MSSM with universal soft terms (CMSSM) for the LHC, based on an improved Bayesian analysis. We do not incorporate ad hoc measures of the fine-tuning to penalize unnatural possibilities: such penalization arises from the Bayesian analysis itself when the experimental value of M-Z is considered. This allows to scan the whole parameter space, allowing arbitrarily large soft terms. Still the low-energy region is statistically favoured (even before including dark matter or g-2 constraints). Contrary to other studies, the results are almost unaffected by changing the upper limits taken for the soft terms. The results are also remarkable stable when using flat or logarithmic priors, a fact that arises from the larger statistical weight of the low-energy region in both cases. Then we incorporate all the important experimental constrains to the analysis, obtaining a map of the probability density of the MSSM parameter space, i.e. the forecast of the MSSM. Since not all the experimental information is equally robust, we perform separate analyses depending on the group of observables used. When only the most robust ones are used, the favoured region of the parameter space contains a significant portion outside the LHC reach. This effect gets reinforced if the Higgs mass is not close to its present experimental limit and persits when dark matter constraints are included. Only when the g-2 constraint (based on e(+)e(-) data) is considered, the preferred region (for μ> 0) is well inside the LHC scope. We also perform a Bayesian comparison of the positive- and negative-mu possibilities. |
Address |
[Eugenia Cabrera, Maria; Alberto Casas, J.] UAM, IFT UAM CSIC, Inst Fis Teor, Madrid 28049, Spain, Email: maria.cabrera@uam.es |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title ![sorted by Original Title field, descending order (down)](img/sort_desc.gif) |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1126-6708 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000278251300005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
435 |
Permanent link to this record |
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Author |
Cabrera, M.E.; Casas, J.A.; Ruiz de Austri, R.; Trotta, R. |
Title |
Quantifying the tension between the Higgs mass and (g-2)(mu) in the constrained MSSM |
Type |
Journal Article |
Year |
2011 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
84 |
Issue |
1 |
Pages |
015006 - 7pp |
Keywords |
|
Abstract |
Supersymmetry has often been invoked as the new physics that might reconcile the experimental muon magnetic anomaly, a(mu), with the theoretical prediction (basing the computation of the hadronic contribution on e(+)e(-) data). However, in the context of the constrained minimal supersymmetric standard model (CMSSM), the required supersymmetric contributions (which grow with decreasing supersymmetric masses) are in potential tension with a possibly large Higgs mass (which requires large stop masses). In the limit of very large m(h) supersymmetry gets decoupled, and the CMSSM must show the same discrepancy as the standard model with a(mu). But it is much less clear for which size of m(h) does the tension start to be unbearable. In this paper, we quantify this tension with the help of Bayesian techniques. We find that for m(h) >= 125 GeV the maximum level of discrepancy given the current data (similar to 3.2 sigma) is already achieved. Requiring less than 3 sigma discrepancy, implies m(h) less than or similar to 120 GeV. For a larger Higgs mass we should give up either the CMSSM model or the computation of a(mu) based on e(+)e(-); or accept living with such an inconsistency. |
Address |
[Cabrera, ME; Casas, JA] UAM, IFT UAM CSIC, Inst Fis Teor, Madrid 28049, Spain, Email: maria.cabrera@uam.es |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title ![sorted by Original Title field, descending order (down)](img/sort_desc.gif) |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000292547200003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
680 |
Permanent link to this record |
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Author |
Cabrera, M.E.; Casas, J.A.; Mitsou, V.A.; Ruiz de Austri, R.; Terron, J. |
Title |
Histogram comparison tools for the search of new physics at LHC. Application to the CMSSM |
Type |
Journal Article |
Year |
2012 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
04 |
Issue |
4 |
Pages |
133 - 27pp |
Keywords |
Beyond Standard Model; Supersymmetric Standard Model; Statistical Methods |
Abstract |
We propose a rigorous and effective way to compare experimental and theoretical histograms, incorporating the different sources of statistical and systematic uncertainties. This is a useful tool to extract as much information as possible from the comparison between experimental data with theoretical simulations, optimizing the chances of identifying New Physics at the LHC. We illustrate this by showing how a search in the CMSSM parameter space, using Bayesian techniques, can effectively find the correct values of the CMSSM parameters by comparing histograms of events with multijets + missing transverse momentum displayed in the effective-mass variable. The procedure is in fact very efficient to identify the true supersymmetric model, in the case supersymmetry is really there and accessible to the LHC. |
Address |
[Eugenia Cabrera, Maria; Alberto Casas, J.] UAM, IFT UAM CSIC, Inst Fis Teor, E-28049 Madrid, Spain, Email: maria.cabrera@uam.es; |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title ![sorted by Original Title field, descending order (down)](img/sort_desc.gif) |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1126-6708 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000304148100059 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
1053 |
Permanent link to this record |
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Author |
Cabrera, M.E.; Casas, J.A.; Ruiz de Austri, R. |
Title |
The health of SUSY after the Higgs discovery and the XENON100 data |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
07 |
Issue |
7 |
Pages |
182 - 47pp |
Keywords |
Supersymmetry Phenomenology |
Abstract |
We analyze the implications for the status and prospects of supersymmetry of the Higgs discovery and the last XENON data. We focus mainly, but not only, on the CMSSM and NUHM models. Using a Bayesian approach we determine the distribution of probability in the parameter space of these scenarios. This shows that, most probably, they are now beyond the LHC reach. This negative chances increase further (at more than 95% c.l.) if one includes dark matter constraints in the analysis, in particular the last XENON100 data. However, the models would be probed completely by XENON1T. The mass of the LSP neutralino gets essentially fixed around 1TeV. We do not incorporate ad hoc measures of the fine-tuning to penalize unnatural possibilities: such penalization arises automatically from the careful Bayesian analysis itself, and allows to scan the whole parameter space. In this way, we can explain and resolve the apparent discrepancies between the previous results in the literature. Although SUSY has become hard to detect at LHC, this does not necessarily mean that is very fine-tuned. We use Bayesian techniques to show the experimental Higgs mass is at similar to 2 sigma off the CMSSM or NUHM expectation. This is substantial but not dramatic. Although the CMSSM or the NUHM are unlikely to show up at the LHC, they are still interesting and plausible models after the Higgs observation; and, if they are true, the chances of discovering them in future dark matter experiments are quite high. |
Address |
[Cabrera, Maria Eugenia] Univ Amsterdam, Inst Theoret Phys, GRAPPA, NL-1012 WX Amsterdam, Netherlands, Email: M.E.CabreraCatalan@uva.nl; |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title ![sorted by Original Title field, descending order (down)](img/sort_desc.gif) |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000323202900095 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1572 |
Permanent link to this record |
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Author |
Cabrera, M.E.; Casas, A.; Ruiz de Austri, R.; Bertone, G. |
Title |
LHC and dark matter phenomenology of the NUGHM |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
12 |
Issue |
12 |
Pages |
114 - 39pp |
Keywords |
Supersymmetry Phenomenology |
Abstract |
We present a Bayesian analysis of the NUGHM, a supersymmetric scenario with non-universal gaugino masses and Higgs masses, including all the relevant experimental observables and dark matter constraints. The main merit of the NUGHM is that it essentially includes all the possibilities for dark matter (DM) candidates within the MSSM, since the neutralino and chargino spectrum -and composition- are as free as they can be in the general MSSM. We identify the most probable regions in the NUHGM parameter space, and study the associated phenomenology at the LHC and the prospects for DM direct detection. Requiring that the neutralino makes all of the DM in the Universe, we identify two preferred regions around m(chi 10) = 1 TeV, 3 TeV, which correspond to the (almost) pure Higgsino and wino case. There exist other marginal regions (e.g. Higgs-funnel), but with much less statistical weight. The prospects for detection at the LHC in this case are quite pessimistic, but future direct detection experiments like LUX and XENON1T, will be able to probe this scenario. In contrast, when allowing other DM components, the prospects for detection at the LHC become more encouraging – the most promising signals being, beside the production of gluinos and squarks, the production of the heavier chargino and neutralino states, which lead to WZ and same-sign WW final states – and direct detection remains a complementary, and even more powerful, way to probe the scenario. |
Address |
[Cabrera, Maria Eugenia; Bertone, Gianfranco] Univ Amsterdam, Inst Theoret Phys, GRAPPA, NL-1018 XE Amsterdam, Netherlands, Email: mcabrera@if.usp.br; |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title ![sorted by Original Title field, descending order (down)](img/sort_desc.gif) |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1029-8479 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000346771200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2063 |
Permanent link to this record |