47 research outputs found
Non-decoupling effects of SUSY in the physics of Higgs bosons and their phenomenological implications
We consider a plausible scenario in the Minimal Supersymmetric Standard Model
(MSSM) where all the genuine supersymmetric (SUSY) particles are heavier than
the electroweak scale. In this situation, indirect searches via their radiative
corrections to low energy observables are complementary to direct searches, and
they can be crucial if the SUSY masses are at the TeV energy range. We
summarize the most relevant heavy SUSY radiative effects in Higgs boson physics
and emphasize those that manifest a non-decoupling behaviour. We focus, in
particular, on the SUSY-QCD non-decoupling effects in fermionic Higgs decays,
flavour changing Higgs decays and Yukawa couplings. Some of their
phenomenological implications at future colliders are also studied.Comment: Invited talk given by M. J. Herrero at the X Mexican School of
Particles and Fields, Playa del Carmen, Mexico, November 200
SUSY Dark Matter: Loops and Precision from Particle Physics
With cosmology entering the era of precision measurements, the synergy with particle physics has strengthened. This new level of precision requires that the dark matter cross sections need to be evaluated with better accuracy at the loop level. We report on the progress in building the automatic code SloopS for generic one-loop calculations in supersymmetry that is applicable for collider observables, the relic density and indirect detection
Quantum corrections to the MSSM h^0 b b-bar vertex: Decoupling limit
We consider the leading one-loop Yukawa-coupling corrections to the h^0 b
b-bar coupling at O(m_t^2)in the MSSM in the decoupling limit. The decoupling
behavior of the corrections from the various MSSM sectors is analyzed in the
case of having some or all of the supersymmetric mass parameters and/or the
CP-odd Higgs mass large as compared to the electroweak scale.Comment: LaTeX, 5 pages, 4 figures. To appear in the Proceedings of the "7th
International Symposium on Radiative Corrections (RADCOR05)", Shonan Village,
Japan, 200
Lepton flavor violating Higgs boson decays from massive seesaw neutrinos
Lepton flavor violating Higgs boson decays are studied within the context of
seesaw models with Majorana massive neutrinos. Two models are considered: The
SM-seesaw, with the Standard Model Particle content plus three right handed
neutrinos, and the MSSM-seesaw, with the Minimal Supersymmetric Standard Model
particle content plus three right handed neutrinos and their supersymmetric
partners. The widths for these decays are derived from a full one-loop
diagrammatic computation in both models, and they are analyzed numerically in
terms of the seesaw parameters, namely, the Dirac and Majorana mass matrices.
Several possible scenarios for these mass matrices that are compatible with
neutrino data are considered. In the SM-seesaw case, very small branching
ratios are found for all studied scenarios. These ratios are explained as a
consequence of the decoupling behaviour of the heavy right handed neutrinos. In
contrast, in the MSSM-seesaw case, sizeable branching ratios are found for some
of the leptonic flavor violating decays of the MSSM neutral Higgs bosons and
for some choices of the seesaw matrices and MSSM parameters. The relevance of
the two competing sources of lepton flavor changing interactions in the
MSSM-seesaw case is also discussed. The non-decoupling behaviour of the
supersymmetric particles contributing in the loop-diagrams is finally shown.Comment: 44pgs. Version to appear in Phys.Rev.
SUSY-QCD decoupling properties in H+ -> t \bar b decay
The SUSY-QCD radiative corrections to the \Gamma (H+ -> t \bar b) partial
decay width are analyzed within the Minimal Supersymmetric Standard Model at
the one-loop level, {\mathcal O}(\alpha_s), and in the decoupling limit. We
present the analytical expressions of these corrections in the large SUSY
masses limit and study the decoupling behaviour of these corrections in various
limiting cases. We find that if the SUSY mass parameters are large and of the
same order, the one loop SUSY-QCD corrections {\it do not decouple}. The
non-decoupling contribution is enhanced by \tan \beta and therefore large
corrections are expected in the large \tan \beta limit. In contrast, we also
find that the SUSY-QCD corrections decouple if the masses of either the squarks
or the gluinos are separately taken large.Comment: LaTeX, 33 pages, 7 figure included. Uses cite.st
Primary myxoid liposarcoma of the supraglottic larynx
Sarcomas are a rare occurrence accounting for roughly 1% of all cancer cases reported. Of these, 9–18% will be identified as liposarcoma. Overall, only 4–9% of all liposarcomas occur in the head and neck region. As such, it is a rare event to see a primary liposarcoma of the aerodigestive tract. These tumors are typically misdiagnosed secondary to their indolent, asymptomatic course and similarities in appearance to other benign lesions. An understanding of these lesions will help clinicians appropriately manage their patients. We present a case of a 60-year male with a primary supraglottic myxoid liposarcoma, and provide relevant information about liposarcomas
Flavour Changing Neutral Higgs Boson Decays from Squark - Gluino Loops
We study the flavour changing neutral Higgs boson decays that can be induced
from genuine supersymmetric particles at the one-loop level and within the
context of the Minimal Supersymmetric Standard Model. We consider all the
possible flavour changing decay channels of the three neutral Higgs bosons into
second and third generation quarks, and focus on the Supersymmetric-QCD
corrections from squark-gluino loops which are expected to provide the dominant
contributions. We assume here the more general hypothesis for flavour mixing,
where there is misalignment between the quark and squark sectors, leading to a
flavour non-diagonal squark mass matrix. The form factors involved, and the
corresponding Higgs partial decay widths and branching ratios, are computed
both analytically and numerically, and their behaviour with the parameters of
the Minimal Supersymmetric Standard Model and with the squark mass mixing are
analyzed in full detail. The large rates found, are explained in terms of the
non-decoupling behaviour of these squark-gluino loop corrections in the
scenario with very large supersymmetric mass parameters. Our results show that
if these decays are seen in future colliders they could provide clear indirect
signals of supersymmetry.Comment: 32 Pages and 12 PostScript Level 2 Figures. Some references adde
Effective Higgs-quark-quark couplings from a heavy SUSY spectrum
In this paper we study the Yukawa Higgs-quark-quark interactions that are
generated from radiative corrections of squarks and gluinos, in the Minimal
Supersymmetric Standard Model. We compute the corrections to the effective
action for Higgs and quark fields that are produced by explicit integration, in
the path integral formalism, of all the squarks and gluinos, at the one-loop
level and order . In addition, we consider the limit of nearly
degenerate heavy squarks and gluinos, with masses much larger than the
electroweak scale, and derive the effective Lagrangian containing all the
relevant new local Higgs-quark-quark interactions. We show that these new
interactions do remain non-vanishing, even in the case of infinitely heavy
supersymmetric particles and, therefore, we demonstrate explicitly the
non-decoupling behavior of squarks and gluinos in Higgs bosons physics. We
present the set of new Yukawa couplings and finally derive the corresponding
one-loop, order , corrections to the Higgs bosons partial decay
widths into quarks.Comment: 21 pages, 1 ps figure. Version to appear in Phys. Rev,
Pan-cancer analysis of whole genomes identifies driver rearrangements promoted by LINE-1 retrotransposition.
About half of all cancers have somatic integrations of retrotransposons. Here, to characterize their role in oncogenesis, we analyzed the patterns and mechanisms of somatic retrotransposition in 2,954 cancer genomes from 38 histological cancer subtypes within the framework of the Pan-Cancer Analysis of Whole Genomes (PCAWG) project. We identified 19,166 somatically acquired retrotransposition events, which affected 35% of samples and spanned a range of event types. Long interspersed nuclear element (LINE-1; L1 hereafter) insertions emerged as the first most frequent type of somatic structural variation in esophageal adenocarcinoma, and the second most frequent in head-and-neck and colorectal cancers. Aberrant L1 integrations can delete megabase-scale regions of a chromosome, which sometimes leads to the removal of tumor-suppressor genes, and can induce complex translocations and large-scale duplications. Somatic retrotranspositions can also initiate breakage-fusion-bridge cycles, leading to high-level amplification of oncogenes. These observations illuminate a relevant role of L1 retrotransposition in remodeling the cancer genome, with potential implications for the development of human tumors