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At least 433 records · Page 24

Data are from Mars, Tools are from Venus

Although during the data production phase, the data producers will usually ensure the products to be easily used by the specific power users the products serve. However, most data products are also posted for general public to use. It is not straightforward for data producers to anticipate what tools that these general end-data users are likely to use. In this talk, we will try to help fill in the gap by going over various tools related to Earth Science and how they work with the existing NASA HDF (Hierarchical Data Format) data products and the reasons why some products cannot be visualized or analyzed by existing tools. One goal is for to give insights for data producers on how to make their data product more interoperable. On the other hand, we also provide some hints for end users on how to make tools work with existing HDF data products. (tool category list: check the comments) HDF-EOS tools: HDFView HDF-EOS Plugin, HEG, h4tonccf, hdf-eos2 dumper, NCL, MATLAB, IDL, etc.net; CDF-Java tools: Panoply, IDV, toosUI, NcML, etc.net; CDF-C tools: ArcGIS Desktop, GrADS, NCL, NCO, etc.; GDAL tools: ArcGIS Desktop, QGIS, Google Earth, etc.; CSV tools: ArcGIS Online, MS Excel, Tableau, etc.

hdf↗

The Chandra Deep Field-South Survey: 7 Ms Source Catalogs

We present X-ray source catalogs for the approx. 7 Ms exposure of the Chandra Deep Field-South (CDF-S), which covers a total area of 484.2 arcmin2. Utilizing WAVDETECT for initial source detection and ACIS Extract for photometric extraction and significance assessment, we create a main source catalog containing 1008 sources that are detected in up to three X-ray bands: 0.5-7.0 keV, 0.5-2.0 keV, and 2-7 keV. A supplementary source catalog is also provided, including 47 lower-significance sources that have bright (Ks < or = 23) near-infrared counterparts. We identify multiwavelength counterparts for 992 (98.4%) of the main-catalog sources, and we collect redshifts for 986 of these sources, including 653 spectroscopic redshifts and 333 photometric redshifts. Based on the X-ray and multiwavelength properties, we identify 711 active galactic nuclei (AGNs) from the main-catalog sources. Compared to the previous approx. 4 Ms CDF-S catalogs, 291 of the main-catalog sources are new detections. We have achieved unprecedented X-ray sensitivity with average flux limits over the central approx. 1 arcmin2 region of 1.9 x 10(exp -17), 6.4 x 10(exp -18), and 2.7 x 10(exp -17) erg/sq cm/s in the three X-ray bands, respectively. We provide cumulative number-count measurements observing, for the first time, that normal galaxies start to dominate the X-ray source population at the faintest 0.5-2.0 keV flux levels. The highest X-ray source density reaches approx. 50,500/sq deg, and 47% +/- 4 of these sources are AGNs (approx. 23,900/sq deg).

cosmology: observations – diffuse radiation – ↗

Functionality of the Python Packages for the HERMES Mission

The Heliophysics Environmental and Radiation Measurement Experiment Suite (HERMES) is a set of four instruments that will fly on the Lunar Gateway, an orbital outpost which will support Artemis lunar operations. HERMES will focus on understanding the causes of space-weather variability as driven by the Sun and modulated by the magnetosphere. In this talk, we will discuss the open source approach of the HERMES Science Operation Center (SOC) team being implemented in a number of Python packages which all work together. We will describe the core package which contains Python interfaces for the loading, calibrating, plotting, validating, and saving of measurement data through Common Data Format (CDF) files making use of pycdf provided by spacepy. Each instrument also has a Python package developed using a package template and will provide specific calibration and processing functionality to each instrument. The packages make extensive use of the scientific Python ecosystem and maintain compatibility with PyHC standards. The abstraction of intricate, high heritage data formats, such as CDF files, in Python enables easier analysis and opens doors for greater participation in heliophysics science.

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Searches for Massive tprime quarks decaying to W + q at the Tevatron

We present searches for pair-production of fourth generation t{prime} quarks in their decays to W{sub q}. We analyze 4.6 fb{sup -1} and 4.3 fb{sup -1} of data collected by the CDF and D0 detectors, respectively, at the Fermilab Tevatron collider at a centre-of-mass energy of {radical}s = 1.96 TeV.We reconstruct the mass of the heavy quark and perform a two-dimensional-fit to the observed (H{sub T},M{sub reco}) distribution to discriminate the new physics signal from standard model backgrounds. As no significant excess of events is observed, we exclude a fourth-generation t{prime} quark with a mass below 335 (296) GeV at 95%CL at CDF (D0).

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Search for New Heavy Particles Decaying to Z0 Z0 to llll, lljj in p pbar Collisions at Sqrt(s) = 1.96 TeV

We report on a search for anomalous production of Z pairs through a massive resonance decay in data corresponding to 2.5-2.9 fb{sup -1} of integrated luminosity in p{bar p} collisions at {radical}s = 1.96 TeV using the CDF II detector at the Fermilab Tevatron. This analysis, with more data and channels where the Z bosons decay to muons or jets, supersedes the 1.1 fb{sup -1} four-electron channel result previously published by CDF. In order to maintain high efficiency for muons, we use a new forward tracking algorithm and muon identification requirements optimized for these high signal-to-background channels. Predicting the dominant backgrounds in each channel entirely from sideband data samples, we observe four-body invariant mass spectra above 300 GeV/c{sup 2} that are consistent with background. We set limits using the acceptance for a massive graviton resonance that are 7-20 times stronger than the previously published direct limits on resonant ZZ production.

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Top Quark Properties at the TeVatron

Discovered in 1995 by CDF and D0 at the Fermilab Tevatron collider, the top quark remains interesting to test the Standard Model. Having collected more than 7 fb{sup -1} of integrated luminosity with both experiments until today, several top quark properties have been measured with increasing precision, while other properties have been investigated for the first time. In this article recent measurements of top quark properties from CDF and D0 are presented, using between 1 fb{sup -1} and 4.8 fb{sup -1} of data. In particular, the measurement of the top quark mass, the top quark width, the top antitop mass difference, a check of the electric charge of the top quark, measurements of the top antitop quark spin correlation and W helicity as well as a search for charged Higgs bosons are discussed.

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SUSY Searches at the Tevatron

The results of search for Supersymmetry performed at the Tevatron Collider by the CDF and D0 collaborations are summarized in this paper. No significant deviations with respect to the Standard Model expectations were observed and constraints were set on supersymmetric parameters. Supersymmetry (SUSY), a space-time symmetry that predicts for every Standard Model (SM) particle the existence of a superpartner that differs by half a unit of spin, may provide a solution to the hierarchy problem if SUSY particles have masses lower than 1 TeV, strongly motivating the search for such particles at the Fermilab Tevatron Collider. If there is supersymmetry in nature, it must be broken and the theorized breaking mechanisms lead to many models (supergravity, gauge mediated, anomaly mediated, ...) with possibly different phenomenologies. Searches performed by the CDF and D0 experiments aim at probing the extensive SUSY parameter space in terms of mass and final state.

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Searches for new physics at the Tevatron

The Tevatron collider has provided the CDF and D0 experiences with large datasets as input to a rich program of searches for physics beyond the standard model. The results presented here are a partial survey of recent searches conducted by the two collaborations using up to 6 fb{sup -1} of data. The standard model (SM) of particles, despite its remarkable description of experimental data at the elementary particle level, has some deficiencies to explain what is observed in the universe: lack of anti-matter, existence of dark matter, etc. Working at the energy frontier, as was the case at the Tevatron for so many years, gives experimentalists the hope to discover new non-SM particles which would indicate some direction to follow at explaining these SM deficiencies. Over the years, the CDF and D0 experiments have gained experience in the detector responses to all particle types. It allows to look at a large number of different final states searching for deviations from the SM expectations. As the knowledge of detector particle responses becomes more accurate, the complexity of final states can increase. For a given final state signature, the non-observation of deviations from the SM prediction allows to constrain several models at once.

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Search for New Physics at the Tevatron

We report on selected recent results from the CDF and D0 experiments on searches for physics beyond the Standard Model using data from the Tevatron collider running p{bar p} collisions at {radical}s = 1960 GeV. Over the past decades the Standard Model (SM) of particle physics has been surprisingly successful. Although the precision of experimental tests improved by orders of magnitude no significant deviation from the SM predictions has been observed so far. Still, there are many questions that the Standard Model does not answer and problems it can not solve. Among the most important ones are the origin of the electro-weak symmetry breaking, hierarchy of scales, unification of fundamental forces and the nature of gravity. Recent cosmological observations indicates that the SM particles only account for 4% of the matter of the Universe. Many extensions of the SM (Beyond the Standard Model, BSM) have been proposed to make the theory more complete and solve some of the above puzzles. Some of these extension includes SuperSymmetry (SUSY), Grand Unification Theory (GUT) and Extra Dimensions. At CDF and D0 we search for evidence of such processes in proton-antiproton collisions at {radical}(s) = 1960 GeV. The phenomenology of these models is very rich, although the cross sections for most of these exotic processes is often very small compared to those of SM processes at hadron colliders. It is then necessary to devise analysis strategies that would allow to disentangle the small interesting signals, often buried under heavy instrumental and/or physics background. Two main approaches to search for physics beyond the Standard Model are used in a complementary fashion: model-based analyses and signature based studies. In the more traditional model-driven approach, one picks a favorite theoretical model and/or a process, and the best signature is chosen. The selection cuts are optimized based on acceptance studies performed using simulated signal events. The expected background is calculated from data and/or Monte Carlo and, based on the number of events observed in the data, a discovery is made or the best limit on the new signal is set. In a signature-based approach a specific signature is picked (i.e. dileptons+X) and the data sample is defined in terms of known SM processes. A signal region (blind box) might be defined with cuts which are kept as loose as possible and the background predictions in the signal region are often extrapolated from control regions. Inconsistencies with the SM predictions will provide indication of possible new physics. As the cuts and acceptances are often calculated independently from a model, different models can be tested against the data sample. It should be noticed that the comparison with a specific model implies calculating optimized acceptances for a specific BSM signal. In signature-based searches, there is no such an optimization. Both the experiments have followed a somehow natural approach in pursuing analysis looking at final state signatures characterized by relatively simple physics objects (for example lepton-only final state, where the selection of the leptons is straightforward and can be easily checked with the measurement of electroweak boson production cross sections) and proceeding onto more complex final state, including jets and heavy flavor. Here more sophisticated identification techniques need to be used and issues like jet energy scale calibration play an important role in determining the final result. Given the limited space available for this proceeding, we will focus here on few selected results.

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Recent B Physics Results from the Tevatron

We review recent B physics results from the CDF and D0 experiments in p{bar p} collisions at {radical}(s) = 1.96 TeV. Using a data sample of 1.4-6.0 fb{sup -1} collected by the CDF II detector we present searches for New Physics in B{sub s} sector and some competitive results with B-factories in the B/charm sector. In the first category we report the BR in B{sub s} J/{Psi} f{sub 0}(980) decays and the time-integrated mixing probability ({bar {chi}}) of B mesons. In the second category BR and A{sub CP} in doubly Cabibbo-suppressed B{sup {+-}} D{sup 0} h{sup {+-}} decays and time-integrated CP violation in D{sup 0} {yields} h{sup +}h{sup -} are presented.

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Non-SUSY Searches at the Tevatron

We present recent results from searches for new physics beyond supersymmetry performed at the Tevatron accelerator at Fermilab. The CDF and D0 analyses presented here utilized data of integrated luminosity up to 6 fb{sup -1}. We cover leptonic and bosonic resonances interpreted in the Randall-Sundrum graviton and new-boson models, rare final states, and the search for vector-like quarks. The search for new phenomena beyond the weak-scale supersymmetry is a vital part of the Fermilab program. Both CDF and D0 experiments at the Tevatron collider actively look for signals not expected by the standard model (SM) or minimal supersymmetric models. The searches can be sorted in three categories: (a) searches for generic resonances that can be interpreted in several new-physics models; (b) searches for exotic combinations of final-state objects or abnormal kinematics (not necessarily predicted by current theories); and (c) model-dependent searches that test a particular theory. We present here latest results from all these categories: searches for new dilepton and diboson resonances (interpreted as gravitons and new gauge bosons), searches for anomalous {gamma} + E{sub T} + X production, and searches for vector-like quarks.

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Observation of the $\Xi_b^0$ Baryon

The first observation of the heavy baryonic state {Xi}{sub b}{sup 0} is reported by the CDF Collaboration. A new decay mode of the established state {Xi}{sub b}{sup -} is also observed. In both cases the decay into a {Xi}{sub c} plus a charged pion is seen, with an equivalent statistical significance of above 6.8{sigma}. The quark model of elementary particles is well established and has a impressive history of success in its account of hadronic states. Nevertheless, it is important to continue to test it by searching for hitherto unobserved particles that are predicted to exist, both to provide continued confirmation of the quark model, and to provide a background for the possible discovery of unusual types of particle. In this presentation we report the first observation, by the CDF Collaboration, of a new baryonic state, the {Xi}{sub b}{sup 0}. This consists of a bsu quark combination and fills an important gap in the set of baryons containing a b quark.

43 PARTICLE ACCELERATORS↗

Summary of the session on the top quark

The CDF and D0 experiments at the Fermilab Tevatron showed recent results on the production and properties of the top quark. The CMS and ATLAS experiments presented first observations of top events at the LHC. Prospects for the top physics at the LHC over the next few years were discussed. CDF and D0 have made remarkable progress in detemerining the properties of the top quark, which so far, conforms to the expectations of the SM. The sophisticated methods they have developed form the basis of the exploration that is now starting at the LHC. New methods, such as the use of boosted top quark signatures, will be necessary to realize fully the potential of the LHC for finding new high mass particles decaying to top and for searching for deviations from the SM. Prospects for the future of top quark physics are very bright.

43 PARTICLE ACCELERATORS↗

Searches for Fourth Generation Fermions

We present the results from searches for fourth generation fermions performed using data samples collected by the CDF II and D0 Detectors at the Fermilab Tevatron p{bar p} collider. Many of these results represent the most stringent 95% C. L. limits on masses of new fermions to-date. A fourth chiral generation of massive fermions with the same quantum numbers as the known fermions is one of the simplest extensions of the SM with three generations. The fourth generation is predicted in a number of theories, and although historically have been considered disfavored, stands in agreement with electroweak precision data. To avoid Z {yields} {nu}{bar {nu}} constraint from LEP I a fourth generation neutrino {nu}{sub 4} must be heavy: m({nu}{sub 4}) > m{sub Z}/2, where m{sub Z} is the mass of Z boson, and to avoid LEP II bounds a fourth generation charged lepton {ell}{sub 4} must have m({ell}{sub 4}) > 101 GeV/c{sup 2}. At the same time due to sizeable radiative corrections masses of fourth generation fermions cannot be much higher the current lower bounds and masses of new heavy quarks t' and b' should be in the range of a few hundred GeV/c{sup 2}. In the four-generation model the present bounds on the Higgs are relaxed: the Higgs mass could be as large as 1 TeV/c{sup 2}. Furthermore, the CP violation is significantly enhanced to the magnitude that might account for the baryon asymmetry in the Universe. Additional chiral fermion families can also be accommodated in supersymmetric two-Higgs-doublet extensions of the SM with equivalent effect on the precision fit to the Higgs mass. Another possibility is heavy exotic quarks with vector couplings to the W boson Contributions to radiative corrections from such quarks with mass M decouple as 1/M{sup 2} and easily evade all experimental constraints. At the Tevatron p{bar p} collider 4-th generation chiral or vector-like quarks can be either produced strongly in pairs or singly via electroweak production, where the latter can be enhanced for vector-like quarks. In the following we present searches for both pair and single production of heavy quarks performed by CDF and D0 Collaborations.

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D0 - D0bar Mixing: An Overview

Recently, the B factory experiments BABAR and Belle as well as the CDF collaboration found evidence for mixing in the D meson system. The current status (beginning of summer 2008) of the experimental results of D{sup 0} mixing is summarized. In this paper, we present an overview of D{sup 0} mixing. After an introduction to the charm mixing phenomenology and analysis techniques, results of the mixing parameters and CP violation as related to mixing are summarized. They are obtained from hadronic two-body, multi-body final states and from quantum correlated D{sup 0} decays of the experiments BABAR, Belle, Cleo and CDF. Mixing results from semileptonic D{sup 0} decays can be found elsewhere.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Test of QCD in multijet final states at the Tevatron

In this contribution, some of the recent QCD results on jet production from the CDF and D0 experiments in Run II of the Tevatron are discussed. In particular, results include cross section measurements for dijet and trijet production, study of jet substructure and measurements of W/Z+jets cross sections. The measurements are compared with the theoretical predictions. The QCD program at the Tevatron proton-antiproton collider revolves around the jet physics. Jets are collimated sprays of hadrons generated by the fragmentation of partons originating from the hard scattering. The measurements of jets production cross section at the Tevatron provide stringent test of perturbative QCD predictions, information on the strong coupling constant, {alpha}s, and constraints on proton parton distribution functions, PDFs. The deviations from the pQCD predictions could translate into a hint of new physics. In addition, these processes form sizable backgrounds to both, the Standard Model (SM) and beyond SM physics processes. Therefore, good understanding of jets production is essential to perform precise physics measurements or searches for new physics phenomena. In this contribution, a review of some recent QCD results from the CDF [1] and D0 [2] experiments is presented. Various analyses use proton-antiproton collision data from the Fermilab Tevatron at the center of mass energy {radical}s = 1.96 TeV corresponding to integrated luminosities of 0.7 fb{sup -1} to 8 fb{sup -1}. The results are corrected for the experimental effects and presented at the 'particle level'. The theory predictions are corrected for the hadronization and underlying effects which are obtained from the parton shower Monte Carlo (MC) simulations.

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Heavy Hadron Spectroscopy and Production at Tevatron

Using data from p{bar p} collisions at {radical}s = 1.96 TeV recorded by the CDFII and D0 detectors at the Fermilab Tevatron, we present recent results on charm and bottom hadrons. The most recent CDF results on properties of the four bottom baryon resonant states {Sigma}{sub b}{sup (*)-}, {Sigma}{sub b}{sup (*)+}. New results on exotic {Upsilon}(4140) state observed by CDF are also reported. A precise measurement of production rates of the lowest lying bottom baryon, {Lambda}{sub b}{sup 0}, produced in the D0 detector is presented.

43 PARTICLE ACCELERATORS↗

New Measurements of Upsilon Spin Alignment at the Tevatron

We describe a new analysis of {Upsilon}(nS) {yields} {mu}{sup +}{mu}{sup -} decays collected in p{bar p} collisions with the CDF II detector at the Fermilab Tevatron. This analysis measures the angular distributions of the final state muons in the {Upsilon} rest frame, providing new information about {Upsilon} production polarization. We find the angular distributions to be nearly isotropic up to {Upsilon} p{sub T} of 40 GeV/c, consistent with previous measurements by CDF, but inconsistent with results obtained by the D0 experiment. The results are compared with recent NLO calculations based on color-singlet matrix elements and non-relativistic QCD with color-octet matrix elements.

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