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The Role of Global Observations for Climate and Other Applications
Most of the current earth-observing systems have been designed primarily for the needs of weather forecasting. Weather forecasting is an initial condition problem; the success of the forecast is heavily dependent on the quality of the specified initial state of the atmosphere. Thus, weather forecasting observing systems tend to focus on determining the 3D values of the state variables of the system – namely temperature, humidity, and wind vector. While weather forecasting requires accurate observations, spatial patterns and relative accuracy across those patterns are the primary concern. Climate, on the other hand, is a boundary condition problem, i.e., climate simulation depends on knowing the energy fluxes into and out of the system, and quantities such as CO2 that affect the flow of those energy fluxes in the system. Consequently, climate-observing systems must extend beyond measurements of state variables to flux measurements of radiation energy and water. We focus on these two cycles because the dominant forms of energy transfer in the climate system (solar energy, thermal infrared energy, evaporation, and condensation) involve these two quantities. Further, because climate is a search for small system trends and imbalances in the midst of large weather variability, climate observations require a much higher …
Date:
May 1, 2005
Creator:
Ackerman, TP
Object Type:
Report
System:
The UNT Digital Library
Cation distribution in a Fe-bearing K-feldspar from Itrongay,Madagascar. A combined neutron- and X-ray single crystal diffractionstudy
We determined the cation distribution and ordering of Si, Al and Fe on the tetrahedral sites of a monoclinic low-sanidine from Itrongay, Madagascar, by combined neutron- and X-ray single-crystal diffraction. The cation distribution was determined by means of a simultaneous refinement using neutron- and X-ray data, as well as by combining scattering densities obtained from separate refinements with chemical data from a microprobe experiment. The two methods give the same results and show that Fe is fully ordered on T1, whereas Al shows a high degree of disorder. Based on this and previously published temperature-dependent X-ray data, we conclude that it is preferential ordering of Fe on T1 even at high temperature, rather than a high diffusion kinetics of Fe, which causes this asymmetry in ordering behavior between Al and Fe. The preferential ordering of Fe3+ relative to Al3+ in T1 is consistent with its 25 percent larger ionic radius.
Date:
May 2, 2005
Creator:
Ackermann, Sonia; Kunz, Martin; Armbruster, Thomas; Schefer,Jurg & Hanni, Henry
Object Type:
Article
System:
The UNT Digital Library
B physics: evidence for the exclusive decay b^+/-_c -> j/psi pi^+ and measurement of the mass of the b^+/-_c meson
We report the first evidence of a fully reconstructed decay mode of the B{sub c}{sup {+-}} meson in the channel B{sub c}{sup {+-}} {yields} J/{psi}{sup {+-}}, with J/{psi} {yields} {mu}{sup +}{mu}{sup -}. The analysis is based on an integrated luminosity of 360 pb{sup -1} in p{bar p} collisions collected by the Collider Detector at Fermilab. We observe 18.9 {+-} 5.7 signal events on a background of 10.0 {+-} 1.4 events and the fit to the J/{psi}{pi}{sup {+-}} mass spectrum yields a B{sub c}{sup {+-}} mass of 6287.0 {+-} 4.8(stat) {+-} 1.1(syst) MeV/c{sup 2}.
Date:
May 25, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
B physics: first evidence for b_s0 --> phi phi decay and measurements of branching ratio and a_cp for b+ --> phi k+
We present the first evidence of charmless decays of the B{sub s}{sup 0} meson, the decay B{sub s}{sup 0} {yields} {phi}{phi}, and a measurement of the Branching Ratio BR(B{sub s}{sup 0} {yields} {phi}{phi}) using 180 pb{sup -1} of data collected by the CDF II experiment at the Fermilab Tevatron collider. In addition, the BR and direct CP asymmetry for the B{sup +} {yields} {phi}K{sup +} decay are measured.
Date:
May 31, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
B physics: measurement of partial widths and search for direct cp violation in d0 meson decays
We present a measurement of relative partial widths and decay rate CP asymmetries in K{sup -}K{sup +} and {pi}{sup -}{pi}{sup +} decays of D{sup 0} mesons produced in p{bar p} collisions at {radical}s = 1.96TeV. We use a sample of 2 x 10{sup 5} D*{sup +} {yields} D{sup 0}{pi}{sup +} (and charge conjugate) decays with the D{sup 0} decaying to K{sup -}{pi}{sup +}, K{sup -}K{sup +}, and {pi}{sup -}{pi}{sup +}, corresponding to 123 pb{sup -1} of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure {Lambda}(D{sup 0} {yields} K{sup -}K{sup +})/{Lambda}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = 0.0992 {+-} 0.0011 {+-} 0.0012, {Lambda}(D{sup 0} {yields} {pi}{sup -}{pi}{sup +})/{Lambda}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = 0.03594 {+-} 0.00054 {+-} 0.00040, A{sub CP} (K{sup -}K{sup +}) = (2.0 {+-} 1.2 {+-} 0.6)%, and A{sub CP} ({pi}{sup -}{pi}{sup +}) = (1.0 {+-} 1.3 {+-} 0.6) %, where, in all cases, the first uncertainty is statistical and the second is systematic.
Date:
April 4, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
B physics: measurement of the lifetime difference between b_s mass eigenstates
We present measurements of the lifetimes and polarization amplitudes for B{sub s}{sup 0} {yields} J/{psi}{phi} and B{sub d}{sup 0} {yields} J/{psi} K*{sup 0} decays. Lifetimes of the heavy (H) and light (L) mass eigenstates in the B{sub s}{sup 0} system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time.
Date:
April 28, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Electroweak physics: measurement of the forward-backward charge asymmetry of electron-positron pairs in p anti-p collisions at s**(1/2) = 1.96 tev
We report a measurement of the forward-backward charge asymmetry of electrons from W boson decays in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample of 170 pb{sup -1} collected by the Collider Detector at Fermilab. The asymmetry is measured as a function of electron rapidity and transverse energy and provides new input on the momentum fraction dependence of the u and d quark parton distribution functions within the proton.
Date:
February 23, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Electroweak physics: measurement of w gamma and z gamma production in pp-bar collisions at s**(1/2) = 1.96 tev
The Standard Model predictions for W{gamma} and Z{gamma} production are tested using an integrated luminosity of 200 pb{sup -1} of p{bar p} collision data collected at the Collider Detector at Fermilab. The cross sections are measured by selecting leptonic decays of the W and Z bosons, and photons with transverse energy E{sub T} > 7 GeV that are well separated from leptons. The production cross sections and kinematic distributions for the W{gamma} and Z{gamma} data are compared to SM predictions.
Date:
February 2, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Electroweak physics: search for zz and zw production in p anti-p collisions at s**(1/2) = 1.96 tev
We present a search for ZZ and ZW vector boson pair production in p{bar p} collisions at {radical}s = 1.96 TeV using the leptonic decay channels ZZ {yields} llvv, ZZ {yields} lll'l' and ZW {yields} lll'v. In a data sample corresponding to an integrated luminosity of 194 pb{sup -1} collected with the Collider Detector at Fermilab, 3 candidate events are found with an expected background of 1.0 {+-} 0.2 events. We set a 95% confidence level upper limit of 15.2 pb on the cross section for ZZ plus ZW production, compared to the standard model prediction of 5.0 {+-} 0.4 pb.
Date:
May 18, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Exotic physics: search for excited and exotic electrons in the e gamma decay channel in p anti-p collisions at s**(1/2) = 1.96 tev
We present a search for excited and exotic electrons (e*) decaying to an electron and a photon, both with high transverse momentum. We use 202 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV with the CDF II detector. No signal above standard model expectation is seen for associated ee* production. We discuss the e* sensitivity in the parameter space of the excited electron mass M{sub e*} and the compositeness energy scale {Lambda}. In the contact interaction model, we exclude 132 GeV/c{sup 2} < M{sub e*} < 879 GeV/c{sup 2} for {Lambda} = M{sub e*} at 95% confidence level (C.L.). In the gauge-mediated model, we exclude 126 GeV/c{sup 2} < M{sub e*} < 430 GeV/c{sup 2} at 95% C.L. for the phenomenological coupling f/{Lambda} {approx} 10{sup -2} GeV{sup -1}.
Date:
February 21, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Exotic physics: search for first-generation scalar leptoquarks in ppbar collisions at sqrt = 1.96 tev
We report on a search for pair production of first-generation scalar leptoquarks (LQ) in p{bar p} collisions at {radical}s = 1.96 TeV using an integrated luminosity of 203 pb{sup -1} collected at the Fermilab Tevatron collider by the CDF experiment. We observe no evidence for LQ production in the topologies arising from LQ{ovr LQ} {yields} eqeq and LQ{ovr LQ} {yields} eq{nu}q, and derive 95% C.L. upper limits on the LQ production cross section. The results are combined with those obtained from a separately reported CDF search in the topology arising from LQ{ovr LQ} {yields} {nu}q{nu}q and 95% C.L. lower limits on the LQ mass as a function of {beta} = BR(LQ {yields} eq) are derived. The limits are 236, 205 and 145 GeV/c{sup 2} for {beta} = 1, {beta} = 0.5 and {beta} = 0.1, respectively.
Date:
June 29, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Exotic physics: search for long-lived doubly-charged higgs bosons in p anti-p collisions at s**(1/2) = 1.96 tev
We present a search for long-lived doubly-charged Higgs bosons (H{sup {+-}{+-}}), with signatures of high ionization energy loss and muon-like penetration. We use 292 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV by the CDF II detector at the Fermilab Tevatron. Observing no evidence of long-lived doubly-charged particle production, we exclude H{sub L}{sup {+-}{+-}} and H{sub R}{sup {+-}{+-}} bosons with masses below 133 GeV/c{sup 2} and 109 GeV/c{sup 2}, respectively. In the degenerate case we exclude H{sup {+-}{+-}} mass below 146 GeV/c{sup 2}. All limits are quoted at the 95% confidence level.
Date:
March 2, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Qcd physics: measurement of the cross section for prompt diphoton production in p anti-p collisions at s**(1/2) = 1.96 tev
We report a measurement of the rate of prompt diphoton production in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample of 207 pb{sup -1} collected with the upgraded Collider Detector at Fermilab (CDF II). The background from non-prompt sources is determined using a statistical method based on differences in the electromagnetic showers. The cross section is measured as a function of the diphoton mass, the transverse momentum of the diphoton system, and the azimuthal angle between the two photons and is found to be consistent with perturbative QCD predictions.
Date:
June 13, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Qcd physics: study of jet shapes in inclusive jet production in ppbar collisions at sqrt s = 1.96 tev
We present a search for excited and exotic electrons (e*) decaying to an electron and a photon, both with high transverse momentum. We use 202 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV with the CDF II detector. No signal above standard model expectation is seen for associated ee* production. We discuss the e* sensitivity in the parameter space of the excited electron mass M{sub e*} and the compositeness energy scale {Lambda}. In the contact interaction model, we exclude 132 GeV/c{sup 2} < M{sub e*} < 879 GeV/c{sup 2} for {Lambda} = M{sub e*} at 95% confidence level (C.L.). In the gauge-mediated model, we exclude 126 GeV/c{sup 2} < M{sub e*} < 430 GeV/c{sup 2} at 95% C.L. for the phenomenological coupling f/{Lambda} {approx} 10{sup -2} GeV{sup -1}.
Date:
May 8, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Top physics: measurement of the cross section for ttbar production in ppbar collisions using the kinematics of lepton + jets events
We present a measurement of the top pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV. We collect a data sample with an integrated luminosity of 194 {+-} 11 pb{sup -1} with the CDF II detector at the Fermilab Tevatron. We use an artificial neural network technique to discriminate between top pair production and background processes in a sample of 519 lepton+jets events, which have one isolated energetic charged lepton, large missing transverse energy and at least three energetic jets. We measure the top pair production cross section to be {sigma}{sub t{bar t}} = 6.6 {+-} 1.1 {+-} 1.5 pb, where the first uncertainty is statistical and the second is systematic.
Date:
April 27, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Top physics: measurement of the tt-bar production cross section in p anti-p collisions at s**(1/2) = 1.96 tev using lepton + jets events with secondary vertex b-tagging
We present a measurement of the t{bar t} production cross section using events with one charged lepton and jets from p{bar p} collisions at a center-of-mass energy of 1.96TeV. In these events, heavy flavor quarks from top quark decay are identified with a secondary vertex tagging algorithm. From 162 pb{sup -1} of data collected by the Collider Detector at Fermilab, a total of 48 candidate events are selected, where 13.5 {+-} 1.8 events are expected from background contributions. We measure a t{bar t} production cross section of 5.6{sub -1.1}{sup _1.2}(stat.){sub -0.6}{sup +0.9}(syst.)pb.
Date:
April 7, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
# top physics: measurement of the ttbar production cross section in pp-bar collisions at sqrt s = 1.96 tev using lepton plus jets events with semileptonic b decays to muons
We present a measurement of the t{bar t} production cross section using 194 pb{sup -1} of CDF II data using events with a high transverse momentum electron or muon, three or more jets, and missing transverse energy. The measurement assumes 100% t {yields} Wb branching fraction. Events consistent with t{bar t} decay are found by identifying jets containing heavy flavor semileptonic decays to muons. The dominant backgrounds are evaluated directly from the data. Based on 20 candidate events and an expected background of 9.5 {+-} 1.1 events, we measure a production cross section of 5.3 {+-} 3.3{sub -1.0}{sup +1.3} pb, in agreement with the standard model.
Date:
June 1, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Top physics: search for electroweak single top quark production in p anti-p collisions at s**(1/2) = 1.96 tev
We report on a search for Standard Model t-channel and s-channel single top quark production in p{bar p} collisions at a center of mass energy of 1.96 TeV. We use a data sample corresponding to 162 pb{sup -1} recorded by the upgraded Collider Detector at Fermilab. We find no significant evidence for electroweak top quark production and set upper limits at the 95% confidence level on the production cross section, consistent with the Standard Model: 10.1 pb for the t-channel, 13.6 pb for the s-channel and 17.8 pb for the combined cross section of t- and s-channel.
Date:
January 12, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Measurement of the Moments of the Hadronic Invariant Mass Distribution in Semileptonic Beta Decays
Using 180 pb{sup -1} of data collected with the CDF II detector at the Tevatron, we measure the first two moments of the hadronic invariant mass-squared distribution in charmed semileptonic B decays. From these we determine the non-perturbative Heavy Quark Effective Theory parameters {Lambda} and {lambda}{sub 1} used to relate the B meson semileptonic branching ratio to the CKM matrix element |V{sub cb}|.
Date:
March 13, 2005
Creator:
Acosta, D. & TITLE=Measuremen, The CDF Collaboration
Object Type:
Report
System:
The UNT Digital Library
Measurement of the cross section for t anti-t production in p anti-p collisions using the kinematics of lepton + jets events
The authors present a measurement of the top pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV. We collect a data sample with an integrated luminosity of 194 {+-} 11 pb{sup -1} with the CDF II detector at the Fermilab Tevatron. We use an artificial neural network technique to discriminate between top pair production and background processes in a sample of 519 lepton + jets events, which have one isolated energetic charged lepton, large missing transverse energy and at least three energetic jets. We measure the top pair production cross section to be {sigma}{sub t{bar t}} = 6.6 {+-} 1.1 {+-} 1.5 pb, where the first uncertainty is statistical and the second is systematic.
Date:
April 1, 2005
Creator:
Acosta, D.; Adelman, J.; Affolder, Anthony A.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the moments of the hadronic invariant mass distribution in semileptonic B decays
None
Date:
February 1, 2005
Creator:
Acosta, D.; Adelman, J.; Affolder, Anthony A.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the forward-backward charge asymmetry from W ---> e nu production in p anti-p collisions at s**(1/2) = 1.96 TeV
None
Date:
January 1, 2005
Creator:
Acosta, D.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the W+ W- production cross section in p anti-p collisions at s**(1/2) =1.96-TeV using dilepton events
We present a measurement of the W{sup +}W{sup -} production cross section using 184 pb{sup -1} of p{bar p} collisions at a center-of-mass energy of 1.96 TeV collected with the Collider Detector at Fermilab. Using the dilepton decay channel W{sup +}W{sup -} {yields} {ell}{sup +}{nu}{ell}{sup -}{ovr {nu}}, where the charged leptons can be either electrons or muons, we find 17 candidate events compared to an expected background of 5.0{sub -0.8}{sup +2.2} events. The resulting W{sup +}W{sup -} production cross section measurement of {sigma}(p{bar p} {yields} W{sup +}W{sup -}) = 14.6{sub -5.1}{sup +5.8}(stat){sub -3.0}{sup +1.8}(syst) {+-} 0.9(lum) pb agrees well with the Standard Model expectation.
Date:
January 1, 2005
Creator:
Acosta, D.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Search for ZZ and ZW production in p anti-p collisions at s**(1/2) = 1.96-TeV
None
Date:
January 1, 2005
Creator:
Acosta, D.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type:
Article
System:
The UNT Digital Library