20 research outputs found
Implications of LHC Searches on SUSY Particle Spectra: The pMSSM Parameter Space with Neutralino Dark Matter
We study the implications of LHC searches on SUSY particle spectra using flat
scans of the 19-parameter pMSSM phase space. We apply constraints from flavour
physics, g_mu-2, dark matter and earlier LEP and Tevatron searches. The
sensitivity of the LHC SUSY searches with jets, leptons and missing energy is
assessed by reproducing with fast simulation the recent CMS analyses after
validation on benchmark points. We present results in terms of the fraction of
pMSSM points compatible with all the constraints which are excluded by the LHC
searches with 1 fb^{-1} and 15 fb^{-1} as a function of the mass of strongly
and weakly interacting SUSY particles. We also discuss the suppression of Higgs
production cross sections for the MSSM points not excluded and contrast the
region of parameter space tested by the LHC data with the constraints from dark
matter direct detection experiments.Comment: 14 pages, 13 figures. v2: increased statistics, to appear in EPJ
The New Look pMSSM with Neutralino and Gravitino LSPs
The pMSSM provides a broad perspective on SUSY phenomenology. In this paper
we generate two new, very large, sets of pMSSM models with sparticle masses
extending up to 4 TeV, where the lightest supersymmetric particle (LSP) is
either a neutralino or gravitino. The existence of a gravitino LSP necessitates
a detailed study of its cosmological effects and we find that Big Bang
Nucleosynthesis places strong constraints on this scenario. Both sets are
subjected to a global set of theoretical, observational and experimental
constraints resulting in a sample of \sim 225k viable models for each LSP type.
The characteristics of these two model sets are briefly compared. We confront
the neutralino LSP model set with searches for SUSY at the 7 TeV LHC using both
the missing (MET) and non-missing ET ATLAS analyses. In the MET case, we employ
Monte Carlo estimates of the ratios of the SM backgrounds at 7 and 8 TeV to
rescale the 7 TeV data-driven ATLAS backgrounds to 8 TeV. This allows us to
determine the pMSSM parameter space coverage for this collision energy. We find
that an integrated luminosity of \sim 5-20 fb^{-1} at 8 TeV would yield a
substantial increase in this coverage compared to that at 7 TeV and can probe
roughly half of the model set. If the pMSSM is not discovered during the 8 TeV
run, then our model set will be essentially void of gluinos and lightest first
and second generation squarks that are \lesssim 700-800 GeV, which is much less
than the analogous mSUGRA bound. Finally, we demonstrate that non-MET SUSY
searches continue to play an important role in exploring the pMSSM parameter
space. These two pMSSM model sets can be used as the basis for investigations
for years to come.Comment: 54 pages, 22 figures; typos fixed, references adde
COSPAR Panel on Planetary Protection Colloquium, Bern, Switzerland, September 2015 (Meeting Reports)
The COSPAR Planetary Protection Policy describes requirements for different planetary protection categories depending on the type of mission, the target body and the type of scientific investigations [1].
Updating the COSPAR Planetary Protection Policy is an iterative process that involves the scientific community. This process is based on new scientific discoveries, new understanding of scientific observations, or, responds to needs identified to prepare future space missions.
In consultation with the COSPAR Scientific Commissions B (Space Studies of the Earth-Moon System, Planets, and Small Bodies of the Solar System) and F (Life Sciences as Related to Space), the COSPAR Panel on Planetary Protection organised a colloquium at the International Space Science Institute (ISSI) in Bern, Switzerland, in September 2015, to discuss two pertinent topics:
- Icy moon sample return planetary protection requirements
- Mars Special Regions planetary protection requirements
These two topics were addressed in two separate sessions.
The recommendations described in this report are based on discussions in the course of the colloquium and reflect a consensus of the colloquium attendees that participated in one or both separate sessions. Any opinions, conclusions, or recommendations expressed in this report are those of the attendee(s) and do not necessarily reflect the views of the organisations that provided support for their participation
Recommended from our members
Spectroscopic observations and analysis of the peculiar SN 1999aa
We present an extensive new time series of spectroscopic data of the peculiar SN 1999aa in NGC 2595. Our data set includes 25 optical spectra between -11 and +58 days with respect to B-band maximum light, providing an unusually complete time history. The early spectra resemble those of an SN 1991T-like object but with a relatively strong Ca H and K absorption feature. The first clear sign of Si II lambda6355, characteristic of Type Ia supernovae, is found at day -7, and its velocity remains constant up to at least the first month after B-band maximum light. The transition to normal-looking spectra is found to occur earlier than in SN 1991T, suggesting SN 1999aa as a possible link between SN 1991T-like and Branch-normal supernovae. Comparing the observations with synthetic spectra, doubly ionized Fe, Si, and Ni are identified at early epochs. These are characteristic of SN 1991T-like objects. Furthermore, in the day -11 spectrum, evidence is found for an absorption feature that could be identified as high velocity C II lambda6580 or H alpha. At the same epoch C III lambda4648.8 at photospheric velocity is probably responsible for the absorption feature at 4500 8. High-velocity Ca is found around maximum light together with Si II and Fe II confined in a narrow velocity window. Implied constraints on supernovae progenitor systems and explosion hydrodynamic models are briefly discussed