91 research outputs found
Effects of Neutrino Inverse Seesaw Mechanism on the Sparticle Spectrum in CMSSM and NUHM2
We study the implications of the inverse seesaw mechanism (ISS) on the
sparticle spectrum in the Constrained Minimal Supersymmetric Standard Model
(CMSSM) and Non-Universal Higgs Model (NUHM2). Employing the maximal value of
the Dirac Yukawa coupling involving the up type Higgs doublet provides a 2-3
GeV enhancement of the lightest CP-even Higgs boson mass. This effect permits
one to have lighter colored sparticles in the CMSSM and NUHM2 scenarios with
LSP neutralino, which can be tested at LHC14. We present a variety of LHC
testable benchmark points with the desired LSP neutralino dark matter relic
abundance.Comment: 18 pages, 10 figures and 2 table
On hyper-reflexivity of some operator spaces
In the present note, we define operator spaces with n-hyper-reflexive property, and prove n-hyper-reflexivity of some operator spaces
SUSY dark matter and lepton flavor violation
We study lepton flavor-violating (LFV) processes within a supersymmetric
type-I seesaw framework with flavor-blind universal boundary conditions,
properly accounting for the effect of the neutrino sector on the dark matter
relic abundance. We consider several possibilities for the neutrino Yukawa
coupling matrix and show that in regions of SUSY parameter space that yield the
correct neutralino relic density, LFV rates can differ from naive estimates by
up to two orders of magnitude. Contrary to common belief, we find that current
LFV limits do not exclude neutrino Yukawa couplings larger than top Yukawa
couplings. We introduce the ISAJET-M program that was used for the
computations.Comment: 37 pages, 9 figures, 6 tables. Version to appear in PR
Implications of a high mass light MSSM Higgs scalar for SUSY searches at the LHC
The Atlas and CMS collaborations have both reported an excess of events in
the WW\star \rightarrow \ell+\ell- + ETmiss search channel, which could be the
first evidence for the Higgs boson. In the context of the MSSM, the lightest
SUSY Higgs scalar h is expected to occur with mass mh = 135 GeV, depending on
the range of SUSY parameters scanned over. Since the h \rightarrow WW\star
branching fraction falls swiftly with decreasing mh, a signal in the WW\star
channel would favor an h at the high end of its predicted mass range. We scan
over general GUT scale SUSY model parameters to find those which give rise to
mh > 130 GeV. A value of m0 \sim 10 - 20 TeV is favored, with A0 \sim \pm2m0,
while the lower range of m1/2 < 1 TeV is also slightly favored. This gives rise
to an "effective SUSY" type of sparticle mass spectrum. For low m1/2, gluino
pair production followed by three-body gluino decay to top quarks may
ultimately be accesible to LHC searches, while for higher m1/2 values, the SUSY
spectra would likely be out of range of any conceivable LHC reach. Since the
thermal neutralino relic abundance tends to be very high, late-time entropy
dilution or neutralino decay to light axinos would be required to gain accord
with the measured dark matter abundanceComment: 12 pages, 3 figures, some references added, accepted in PR
Инородное тело пищевода у годовалого ребенка (открытая английская булавка)
The authors report a case of practice: a foreign body (an open safety pin) in the esophagus of a one-year-old child. This case highlights the risk of accidental swallowing a safety pin, which can lead to serious complications.Авторы представляют случай из практики: инородное тело (открытая английская булавка) в пищеводе у годовалого ребенка. Данный случай подчеркивает риск случайного проглатывания ребенком английской булавки, которая может привести к серьезным осложнениям
Phylogeny, phylogeography and hybridization of Caucasian barbels of the genus Barbus (Actinopterygii, Cyprinidae)
Phylogenetic relationships and phylogeography of six species of Caucasian barbels, the genus Barbus s. str., were studied based on extended geographic coverage and using mtDNA and nDNA markers. Based on 27 species studied, matrilineal phylogeny of the genus Barbus is composed of two clades ¿ (a) West European clade, (b) Central and East European clade. The latter comprises two subclades: (b1) Balkanian subclade, and (b2) Ponto-Caspian one that includes 11 lineages mainly from Black and Caspian Sea drainages. Caucasian barbels are not monophyletic and subdivided for two groups. The Black Sea group encompasses species from tributaries of Black Sea including re-erected B. rionicus and excluding B. kubanicus. The Caspian group includes B. ciscaucasicus, B. cyri (with B. goktschaicus that might be synonymized with B. cyri), B. lacerta from the Tigris-Euphrates basin and B. kubanicus from the Kuban basin. Genetic structure of Black Sea barbels was influenced by glaciation-deglaciation periods accompanying by freshwater phases, periods of migration and colonization of Black Sea tributaries. Intra- and intergeneric hybridization among Caucasian barbines was revealed. In the present study, we report about finding of B. tauricus in the Kuban basin, where only B. kubanicus was thought to inhabit. Hybrids between these species were detected based on both mtDNA and nDNA markers. Remarkably, Kuban population of B. tauricus is distant to closely located conspecific populations and we consider it as relic. We highlight revealing the intergeneric hybridization between evolutionary tetraploid (2n=100) B. goktschaicus and evolutionary hexaploid (2n=150) Capoeta sevangi in Lake Sevan.The study was supported by Russian Science Foundation (grant no. 15-14-10020); final stage of the study was supported by Russian Foundation for Basic Research (grants nos. 18-54-05003 and 19-04-00719)
Target dark matter detection rates in models with a well-tempered neutralino
In the post-LEP2 era, and in light of recent measurements of the cosmic
abundance of cold dark matter (CDM) in the universe from WMAP, many
supersymmetric models tend to predict 1. an overabundance of CDM and 2.
pessimistically low rates for direct detection of neutralino dark matter.
However, in models with a ``well-tempered neutralino'', where the neutralino
composition is adjusted to give the measured abundance of CDM, the neutralino
is typically of the mixed bino-wino or mixed bino-higgsino state. Along with
the necessary enhancement to neutralino annihilation rates, these models tend
to give elevated direct detection scattering rates compared to predictions from
SUSY models with universal soft breaking terms. We present neutralino direct
detection cross sections from a variety of models containing a well-tempered
neutralino, and find cross section asymptotes with detectable scattering rates.
These asymptotic rates provide targets that various direct CDM detection
experiments should aim for. In contrast, in models where the neutralino mass
rather than its composition is varied to give the WMAP relic density via either
resonance annihilation or co-annihilation, the neutralino remains essentially
bino-like, and direct detection rates may be below the projected reaches of all
proposed experiments.Comment: 13 pages including 1 EPS figur
Direct, Indirect and Collider Detection of Neutralino Dark Matter In SUSY Models with Non-universal Higgs Masses
In supersymmetric models with gravity-mediated SUSY breaking, universality of
soft SUSY breaking sfermion masses m_0 is motivated by the need to suppress
unwanted flavor changing processes. The same motivation, however, does not
apply to soft breaking Higgs masses, which may in general have independent
masses from matter scalars at the GUT scale. We explore phenomenological
implications of both the one-parameter and two-parameter non-universal Higgs
mass models (NUHM1 and NUHM2), and examine the parameter ranges compatible with
Omega_CDM h^2, BF(b --> s,gamma) and (g-2)_mu constraints. In contrast to the
mSUGRA model, in both NUHM1 and NUHM2 models, the dark matter A-annihilation
funnel can be reached at low values of tan(beta), while the higgsino dark
matter annihilation regions can be reached for low values of m_0. We show that
there may be observable rates for indirect and direct detection of neutralino
cold dark matter in phenomenologically aceptable ranges of parameter space. We
also examine implications of the NUHM models for the Fermilab Tevatron, the
CERN LHC and a Sqrt(s)=0.5-1 TeV e+e- linear collider. Novel possibilities
include: very light s-top_R, s-charm_R squark and slepton_L masses as well as
light charginos and neutralinos and H, A and H^+/- Higgs bosons.Comment: LaTeX, 48pages, 26 Figures. The version with high resolution Figures
is available at http://hep.pa.msu.edu/belyaev/public/projects/nuhm/nuhm.p
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