3 research outputs found
Study of exclusive one-pion and one-eta production using hadron and dielectron channels in pp reactions at kinetic beam energies of 1.25 GeV and 2.2 GeV with HADES
We present measurements of exclusive ensuremathπ+,0 and η production in pp reactions at 1.25GeV and 2.2GeV beam kinetic energy in hadron and dielectron channels. In the case of π+ and π0 , high-statistics invariant-mass and angular distributions are obtained within the HADES acceptance as well as acceptance-corrected distributions, which are compared to a resonance model. The sensitivity of the data to the yield and production angular distribution of Δ (1232) and higher-lying baryon resonances is shown, and an improved parameterization is proposed. The extracted cross-sections are of special interest in the case of pp → pp η , since controversial data exist at 2.0GeV; we find \ensuremathσ=0.142±0.022 mb. Using the dielectron channels, the π0 and η Dalitz decay signals are reconstructed with yields fully consistent with the hadronic channels. The electron invariant masses and acceptance-corrected helicity angle distributions are found in good agreement with model predictions
The ATLAS High Level Trigger Steering Framework and the Trigger Configuration System.
The ATLAS High Level Trigger Steering Framework and the Trigger
Configuration System.
The ATLAS detector system installed in the Large Hadron Collider (LHC)
at CERN is designed to study proton-proton and nucleus-nucleus
collisions with a maximum center of mass energy of 14 TeV at a bunch
collision rate of 40MHz. In March 2010 the four LHC experiments saw
the first proton-proton collisions at 7 TeV. Still within the year a
collision rate of nearly 10 MHz is expected. At ATLAS, events of
potential interest for ATLAS physics are selected by a three-level
trigger system, with a final recording rate of about 200 Hz. The first
level (L1) is implemented in custom hardware; the two levels of
the high level trigger (HLT) are software triggers, running on large
farms of standard computers and network devices.
Within the ATLAS physics program more than 500 trigger signatures are
defined. The HLT tests each signature on each L1-accepted event; the
test outcome is recorded for later analysis. The HLT-Steering is
responsible for this. It foremost ensures the independent test of each
signature, guarantying unbiased trigger decisions. Yet, to minimize
data readout and execution time, cached detector data and
once-calculated trigger objects are reused to form the decision. Some
signature tests are performed only on a scaled-down fraction of
candidate events, in order to redu ce the output rate and further limit
the execution time. For some signatures it is important to physics
analysts to know the would-be decision of that test when it was scaled
out. For this the HLT-Steering is equipped with a test-after-accept
feature.
The HLT-Steering receives the setup of the signatures from the trigger
configuration system. This system dynamically provides the online
setup for the L1 and HLT, e.g. L1 trigger thresholds and
multiplicities, and HLT algorithm configuration and trigger objects
selection criteria. It also archives the trigger configuration for
analysis, which is crucial for understanding trigger efficiencies.
The configuration system uses a relational database (TriggerDB) to
store all configuration information. A graphical user interface, the
Trigger Tool, is provided to interact with the TriggerDB. Services are
provided to access configuration data for online, offline, and Monte
Carlo processing. A web interface to the TriggerDB is available to the
ATLAS user to look at the trigger configuration remotely.
This poster will introduce the ATLAS trigger with focus on the trigger
configuration, steering, and resource monitoring system. It will point
out the implications of the system design for physics analysis. It
will also present performance figures from the first year of
successful operation with proton-proton and heavy ion coll i sions
Global consortium for the classification of fungi and fungus-like taxa
The Global Consortium for the Classification of Fungi and fungus-like taxa is an international initiative of more than 550 mycologists to develop an electronic structure for the classification of these organisms. The members of the Consortium originate from 55 countries/regions worldwide, from a wide range of disciplines, and include senior, mid-career and early-career mycologists and plant pathologists. The Consortium will publish a biannual update of the Outline of Fungi and fungus-like taxa, to act as an international scheme for other scientists. Notes on all newly published taxa at or above the level of species will be prepared and published online on the Outline of Fungi website (https://www.outlineoffungi.org/), and these will be finally published in the biannual edition of the Outline of Fungi and fungus-like taxa. Comments on recent important taxonomic opinions on controversial topics will be included in the biannual outline. For example, 'to promote a more stable taxonomy in Fusarium given the divergences over its generic delimitation', or 'are there too many genera in the Boletales?' and even more importantly, 'what should be done with the tremendously diverse 'dark fungal taxa?' There are undeniable differences in mycologists' perceptions and opinions regarding species classification as well as the establishment of new species. Given the pluralistic nature of fungal taxonomy and its implications for species concepts and the nature of species, this consortium aims to provide a platform to better refine and stabilise fungal classification, taking into consideration views from different parties. In the future, a confidential voting system will be set up to gauge the opinions of all mycologists in the Consortium on important topics. The results of such surveys will be presented to the International Commission on the Taxonomy of Fungi (ICTF) and the Nomenclature Committee for Fungi (NCF) with opinions and percentages of votes for and against. Criticisms based on scientific evidence with regards to nomenclature, classifications, and taxonomic concepts will be welcomed, and any recommendations on specific taxonomic issues will also be encouraged; however, we will encourage professionally and ethically responsible criticisms of others' work. This biannual ongoing project will provide an outlet for advances in various topics of fungal classification, nomenclature, and taxonomic concepts and lead to a community-agreed classification scheme for the fungi and fungus-like taxa. Interested parties should contact the lead author if they would like to be involved in future outlines. </div