Physical Sciences and Mathematics Commons^™

The East Texas Caddo: Modeling Tempo And Place, Robert Z. Selden Jr., Timothy K. Perttula

CRHR: Archaeology

Analysis of the Caddo sample (n=889 dates) from the East Texas radiocarbon database is used to establish the tempo and place of Caddo era (ca. A.D. 800-1680) archaeological sites, site clusters, and communities across the region. The temporal and spatial distribution of radiocarbon ages from settlements, mound centers, and cemeteries across the region have utility in exploring the development and geographical continuity of the Caddo peoples; establishing the specific times when areas were abandoned or population sizes diminished; and defining times and areas illustrating an intensification in mound center construction and large cemeteries became a focus of community social practices.

A Performance Comparison Of Mobile Wimax Spectrums: 2.5 Ghz Vs. 3.65 Ghz, Pradhumna Shrestha, Michael Hempel, Puttipong Mahasukhon, Tao Ma, Hamid Sharif

CSE Conference and Workshop Papers

Mobile WiMAX is a popular broadband solution with diverse applications. In the United States, the Federal Communications Commission (FCC) currently issues licenses for Mobile WiMAX in several frequency bands, of which 2.5 GHz and 3.65 GHz are the most prevalent. A significant amount of research has been conducted in the domain of 2.5 GHz due to its widespread commercial use. However, no such work – academic or industrial – has been reported for 3.65 GHz, in spite of it being a more favorable option for many applications, particularly because of its licensing requirements. In this paper, we present a comprehensive …

Droughtscape- Winter 2012, National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Drought Planning for Kansas Ranchers Jan. 21

South Hoping La Niña Dryness Stays Away

2011 Brought Record-Breaking Extent of D4

Reported Impacts Ease as Growing Season Ends

Disaster Planning in Nanjing at Hohai U

Ag, Fire and Water Supply Topped 2011 Impacts

Spin And Elastic Contributions To Isothermal Entropy Change, Tathagata Mukherjee, Ralph Skomski, Steven A. Michalski, David J. Sellmyer, Christian Binek

David Sellmyer Publications

Statistical considerations of ensembles of localized magnetic moments reveal an upper bound of the isothermal entropy change when only the magnetic degrees of freedom are considered. In this case, the maximum molar isothermal entropy change is determined by the spin multiplicity and is equal to Rln(2J+1), where J is the angular momentum of an individual atom. However, in materials with giant magnetocaloric effect, the isothermal field-induced entropy change goes beyond the spin-multiplicity limit due to field-activated elastic degrees of freedom. Recently, we investigated a model of pairs of exchange-coupled Ising spins with variable real-space positions. We …

Isothermal Entropy Changes In Nanocomposite Co:Ni67Cu33, Steven A. Michalski, Ralph Skomski, Xingzhong Li, Damien Le Roy, Tathagata Mukherjee, Christian Binek, David J. Sellmyer

David Sellmyer Publications

The temperature-dependent magnetic properties of artificial rare-earth, free-magnetic nanostructures are investigated for magnetic cooling. We consider two-phase nanocomposites, where 2 nm nanoclusters of cobalt are embedded in a Ni₆₇Cu₃₃ matrix. Several composite films were produced by cluster deposition. The average Co nanocluster size can be tuned by varying the deposition conditions. Isothermalmagnetization curves weremeasured at various temperatures 150K

Structure And Magnetic Properties Of Co-W Clusters Produced By Inert Gas Condensation, Farhad Reza Golkar-Fard, Matthew J. Kramer, Y. Zhang, R. W. Mccallum, Ralph Skomski, David J. Sellmyer, Jeffrey E. Shield

David Sellmyer Publications

In this article, inert-gas condensation was used to synthesize Co-W clusters. The formation, structure, and magnetic properties of the clusters were investigated. Sub-10-nm clusters were obtained, and the structures and average sizes were strongly dependent on sputtering power. At low sputtering powers, the clusters were predominantly amorphous, while, at high sputtering power, the clusters were crystalline. X ray diffraction and transmission electron microscopy revealed clusters with hcp structure at high sputtering power. The magnetic properties were dependent on the sputtering power and temperature, with the highest coercivity of 810 Oe at 10 K for high sputtering power.

Magnetism Of Directly Ordered Sm-Co Clusters, Balamurugan Balasubramanian, Ralph Skomski, Xingzhong Li, George C. Hadjipanayis, David J. Sellmyer

David Sellmyer Publications

Sm-Co bulk alloys have shown superior permanent-magnet properties, but research on Sm-Co nanoparticles is challenging because of the need to control particle size, size-distribution, crystalline ordering, and phase purity. In the present study, a cluster-deposition method was used to produce Sm-Co nanoparticles having desired crystal structures without the requirement of subsequent high-temperature thermal annealing. Poorly crystallized SmCo₅ nanoparticles exhibit a low room-temperature coercivity of only 100 Oe, whereas crystalline SmCo₅ and Sm₂Co₁₇ nanoparticles show room-temperature coercivities of 2000 and 750 Oe, respectively. The direct synthesis of Sm-Co nanoparticles having sizes of less than 10 nm …

Aligned And Exchange-Coupled L10 (Fe,Co)Pt-Based Magnetic Films, Yi Liu, Thomas A. George, Ralph Skomski, David J. Sellmyer

David Sellmyer Publications

Films of aligned L1₀-structure (Fe,Co)Pt with fcc Fe(Co,Pt) are synthesized by co-sputtering Fe, Co, and Pt on an (001) MgO substrate with in situ heating at 830 degrees C. The nanostructures and magnetic properties of the films are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and superconducting quantum interference device (SQUID). The compositions of the samples (Fe,Co)_xPt_1-x are designed to maintain an atomic Fe: Co ratio of 65: 35 while increasing the Fe,Co content in each successive sample. In samples with low Fe and Co concentration, the XRD patterns exhibit three strong peaks, …

Structural, Magnetic, And Electron Transport Properties Of Mnbi:Fe Thin Films, Parashu Kharel, Xingzhong Li, Shah R. Valloppilly, Nabil M. Al-Aqtash, K. Tarawneh, Renat F. Sabirianov, Ralph Skomski, David J. Sellmyer

David Sellmyer Publications

The structural, magnetic, and electron transport properties of Mn55=xFexBi45 (x¼0, 2, 4, 5, 8, 11, 13, 16) films prepared by multilayer deposition and annealing using e-beam evaporation have been investigated. Fe doping has produced a significant change in the magnetic properties of the samples including the decrease in saturation magnetization and magnetocrystalline anisotropy and increase in coercivity. Although the magnetization shows a smooth decrease with increasing Fe concentration, the coercivity jumps abruptly from 8.5 kOe to 22 kOe as Fe content changes from 4% to 5%, but the change in coercivity is small as the concentration goes beyond 5%. The …

Assembly Of Uniaxially Aligned Rare-Earth-Free Nanomagnets, Balamurugan Balamurugan, Bhaskar Das, Shah R. Valloppilly, Ralph Skomski, Xingzhong Li, David J. Sellmyer

David Sellmyer Publications

We report HfCo₇ nanoparticles with appreciable permanent-magnet properties (magnetocrystalline anisotropy K₁≈10 Mergs/cm³, coercivity H_c ≈ 4.4 kOe, and magnetic polarization J_s≈10.9 kG at 300 K) deposited by a single-step cluster-deposition method. The direct crystalline-ordering of nanoparticles during the gas-aggregation process, without the requirement of a high-temperature thermal annealing, provides an unique opportunity to align their easy axes uniaxially by applying a magnetic field of about 5 kOe prior to deposition, and subsequently to fabricate exchange-coupled nanocomposites having J_s as high as 16.6 kG by co-depositing soft magnetic Fe-Co. This study suggests …

Effects Of Deposition Temperature And In-Situ Annealing Time On Structure And Magnetic Properties Of (001) Orientation Fept Films, Yongsheng Yu, T A. George, Haibo Li, Daqian Sun, Zhenan Ren, David J. Sellmyer

David Sellmyer Publications

FePt films were prepared on (100) oriented single crystal MgO substrates at high temperature rang-ing from 620 until 800°C and in-situ annealed for different times ranging from 0 to 60 min to obtain ordered FePt films. The structural analysis indicates that FePt films grow epitaxially on MgO (100) substrates. Both increasing deposition temperature and in-situ annealing time enhance the (001) tex-ture and ordering of FePt films. The magnetic analysis shows that these L10 FePt films have perpen-dicular anisotropy and the easy magnetization c-axis is perpendicular to the film plane. Magnetization reversal is controlled by a rotational mechanism. The hard magnetic …

Measurement Of The Cp-Violating Phase Φsj/ᴪφ Using The Flavor-Tagged Decay B0s→J/ᴪφ In 8 Fb-1 Of Pp̅ Collisions, V. M. Abazov, Kenneth A. Bloom, Daniel R. Claes, Kayle Devaughan, Aaron Dominguez, Michael Eads, Ioannis Katsanos, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

We report an updated measurement of the CP-violating phase, Φ_s^J/ᴪΦ, and the decay-width difference for the two mass eigenstates, ∆Ӷs, from the flavor-tagged decay B⁰_s → J/ᴪΦ. The data sample corresponds to an integrated luminosity of 8.0 fb^-1 accumulated with the D0 detector using pp̅ collisions at √s= 1.96 TeV produced at the Fermilab Tevatron collider. The 68% Bayesian credibility intervals, including systematic uncertainties, are ∆Ӷs = 0.163 ^{+ 0.065}_-0.064 ps^-1 and Φ_s^J/ᴪΦ= -0.55^+0.38_-0.36. The p-value for the Standard Model point is …

Inclusive Search For Squarks And Gluinos In Pp̅ Collisions At √S= 7 Tev, S. Chatrchyan, Kenneth A. Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, T. Kelly, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory R. Snow

Kenneth Bloom Publications

A search is performed for heavy particle pairs produced in √s= 7 TeV proton-proton collisions with 35 pb^-1 of data collected by the CMS experiment at the LHC. The search is sensitive to squarks and gluinos of generic supersymmetry models, provided they are kinematically accessible, with minimal assumptions on properties of the lightest superpartner particle. The kinematic consistency of the selected events is tested against the hypothesis of heavy particle pair production using the dimensionless razor variable R, related to the missing transverse energy E^miss _T . The new physics signal is characterized by a broad …

Search For Universal Extra Dimensions In Pp Collisions, V. M. Abazov, Kenneth A. Bloom, Daniel R. Claes, Kayle Devaughan, Aaron Dominguez, Michael Eads, Ioannis Katsanos, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

We present a search for Kaluza-Klein (KK) particles predicted by models with universal extra dimensions (UED) using a data set corresponding to an integrated luminosity of 7.3 fb^-1, collected by the D0 detector at a pp̅ center-of-mass energy of 1.96 TeV. The decay chain of KK particles can lead to a final state with two muons of the same charge. This signature is used to set a lower limit on the compactification scale of R^-1 > 260 GeV in a minimal UED model.

Search For Charged Massive Long-Lived Particles, V. M. Abazov, Kenneth A. Bloom, Daniel R. Claes, Kayle Devaughan, Aaron Dominguez, Michael Eads, Ioannis Katsanos, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

We report on a search for charged massive long-lived particles (CMLLPs), based on 5.2 fb^-1 of integrated luminosity collected with the D0 detector at the Fermilab Tevatron pp̅ collider. We search for events in which one or more particles are reconstructed as muons but have speed and ionization energy loss (dE/dx) inconsistent with muons produced in beam collisions. CMLLPs are predicted in several theories of physics beyond the standard model. We exclude pair-produced long-lived gauginolike charginos below 267 GeV and Higgsino-like charginos below 217 GeV at 95% C.L., as well as longlived scalar top quarks with mass …

Measurement Of Isolated Photon Production In Pp And Pbpb Collisions At √Snn = 2.76 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, Jose Lazo-Flores, Helena Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

Isolated photon production is measured in proton–proton and lead–lead collisions at nucleon–nucleon centre-of-mass energies of 2.76 TeV in the pseudorapidity range |η| < 1.44 and transverse energies E_T between 20 and 80 GeV with the CMS detector at the LHC. The measured E_T spectra are found to be in good agreement with next-to-leading-order perturbative QCD predictions. The ratio of PbPb to pp isolated photon E_T -differential yields, scaled by the number of incoherent nucleon–nucleon collisions, is consistent with unity for all PbPb reaction centralities.

Search For Heavy Majorana Neutrinos In Μ±Μ± +Jets And E±E± + Jets Events In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, J. Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

A search is performed for heavy Majorana neutrinos (N) using an event signature defined by two samesign charged leptons of the same flavour and two jets. The data correspond to an integrated luminosity of 4.98 fb⁻¹ of pp collisions at a centre-of-mass energy of 7 TeV collected with the CMS detector at the Large Hadron Collider. No excess of events is observed beyond the expected standard model background and therefore upper limits are set on the square of the mixing parameter, |V_ℓN|², for ℓ = e,μ, as a function of heavy Majorana-neutrino …

Search For Narrow Resonances In Dilepton Mass Spectra In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

A search for narrow, high-mass resonances decaying to electron or muon pairs has been performed using pp collision data collected at √s = 7 TeV by the CMS experiment in 2011. The data sample corresponds to an integrated luminosity of approximately 5 fb⁻¹. The event yields observed in the signal regions are consistent with predictions of the standard model backgrounds, and upper limits on the cross section times branching fraction for a resonance decaying to dileptons are extracted from a shape analysis of the dilepton invariant mass distribution. The resulting mass limits at 95% confidence level are …

Search For Physics Beyond The Standard Model In Events With A Z Boson, Jets, And Missing Transverse Energy In Pp Collisions At √S = 7 Tev, Cms Collaboration, Ekaterina Avdeeva, Kenneth A. Bloom, S. Bose, Jamila Butt, Daniel R. Claes, Aaron Dominguez, Michael Eads, P. Jindal, J. Keller, Ilya Kravchenko, J. Lazo-Flores, H. Malbouisson, Sudhir Malik, Gregory Snow

Kenneth Bloom Publications

A search is presented for physics beyond the standard model (BSM) in events with a Z boson, jets, and missing transverse energy (E^miss_T ). This signature is motivated by BSM physics scenarios, including supersymmetry. The study is performed using a sample of proton–proton collision data collected at √s = 7 TeV with the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.98 fb⁻¹. The contributions from the dominant standard model backgrounds are estimated from data using two complementary strategies, the jet-Z balance technique and a method based on modeling E^miss_T with …

Surface State Engineering Of Molecule–Molecule Interactions, Geoffrey Rojas, Scott Simpson, Xumin Chen, Donna A. Kunkel, Justin Nitz, Jie Xiao, Peter A. Dowben, Eva Zurek, Axel Enders

Axel Enders Publications

Engineering the electronic structure of organics through interface manipulation, particularly the interface dipole and the barriers to charge carrier injection, is of essential importance to improve organic devices. This requires the meticulous fabrication of desired organic structures by precisely controlling the interactions between molecules. The well-known principles of organic coordination chemistry cannot be applied without proper consideration of extra molecular hybridization, charge transfer and dipole formation at the interfaces. Here we identify the interplay between energy level alignment, charge transfer, surface dipole and charge pillow effect and show how these effects collectively determine the net force between adsorbed porphyrin 2H-TPP …

Evolution With Depth From Detrital To Authigenic Smectites In Sediments From And-2a Drill Core (Mcmurdo Sound, Antarctica), Francesco Iacoviello, Giovanna Giorgetti, Fernando Nieto, Isabella Turbanti Memmi

ANDRILL Research and Publications

We have examined the nature and origin of smectites in glaciomarine sediments of the AND-2A drill core (McMurdo Sound, Antarctica) by means of X-ray diffraction (XRD) analyses on the clay fraction, field emission scanning electron microscopy (FESEM), scanning electron microscopy (SEM) observations and SEM-EDS microanalyses on smectite particles. Relying on the smectite variation throughout the drill core it was possible to split the sequence into three units. Smectites throughout the core are either detrital or authigenic. Detrital smectites are close to montmorillonite-beidellite in composition while newly-formed smectites frequently have higher Fe-Mg contents and intermediate compositions between the saponite and nontronite …

Fragilariopsis Tigris Sp. Nov., A New Late Pliocene Antarctic Continental Shelf Diatom With Biostratigraphic Promise, Christina R. Riesselman

ANDRILL Research and Publications

Anew species within the genus Fragilariopsis, F. tigris, is described and illustrated using light microscopy and scanning electron microscopy. This species is restricted to a single 8-meter-thick diatom unit within the 585-meter-long section of alternating diatomites and diamictites recovered in the upper portion of the ANtarctic geological DRILLing (ANDRILL) McMurdo Ice Shelf Project (MIS) AND-1B marine sediment core. This new taxon from a diverse, well-preserved diatom assemblage is inferred to be the youngest member of the well-documented, biostratigraphically useful F. praeinterfrigidaria – F. interfrigidaria – F. weaveri lineage and may represent a near-shore corollary to the open-ocean species …

Diatom Evidence For The Onset Of Pliocene Cooling From And-1b, Mcmurdo Sound, Antarctica, Christina R. Riesselman, Robert B. Dunbar

ANDRILL Research and Publications

The late Pliocene, ~3.3–3.0 Ma, is the most recent interval of sustained global warmth in the geologic past. This window is the focus of climate reconstruction efforts by the U.S. Geological Survey’s Pliocene Research, Interpretation, and Synoptic Mapping (PRISM) Data/Model Cooperative, and may provide a useful climate analog for the coming century. Reconstructions of past surface ocean conditions proximal to the Antarctic continent are essential to understanding the sensitivity of the cryosphere to this key interval in Earth’s climate evolution. An exceptional marine sediment core collected from the southwestern Ross Sea (78° S), Antarctica, during ANDRILL’s McMurdo Ice Shelf Project …

A Diatom Record Of Late Pliocene Cooling From The Ross Sea Continental Shelf, And-1b, Antarctica, Charlotte Sjunneskog, Diane Winter

ANDRILL Research and Publications

A late Pliocene – early Pleistocene, 2.9–2.0Ma, diatom record from the Antarctic Geological Drilling Program (ANDRILL) MIS drillcore AND-1B is presented. This core, recovered from beneath the Ross Ice Shelf south of Ross Island, comprises multiple diatomaceous-sediment units deposited during interglacial periods with open water over the core site. These represent interglacial phases of orbitally paced climate cycles and are punctuated by glacial advances. Extant diatom assemblages have limited presence in the late Pliocene record, which makes environmental interpretation less straight forward. We employ modern ecological data in combination with late Pliocene to present variation in diatom assemblages across the …

Fragilariopsis Diatom Evolution In Pliocene And Pleistocene Antarctic Shelf Sediments, Charlotte Sjunneskog, Christina R. Riesselman, Diane Winter, Reed Scherer

ANDRILL Research and Publications

The late Pliocene – early Pleistocene sediment record in the AND-1B core from the McMurdo Sound, Ross Sea, Antarctica, displays a rich diversity and high abundance of diatoms, including several new morphologies within the genus Fragilariopsis. These new morphologies exhibit similarities to the extinct late Miocene/early Pliocene species Fragilariopsis aurica Gersonde and Fragilariopsis praecurta Gersonde, as well as to the modern sea ice-associated species Fragilariopsis ritscheri Hustedt and Fragilariopsis obliquecostata van Heurck. From the diverse morphologies present, we use light microscopy and scanning electron microscopy to identify and describe the characteristics of three new taxa, Fragilariopsis laqueata Riesselman, Fragilariopsis …

To Burn Or Not To Burn Oriental Bittersweet: A Fire Manager’S Conundrum, Noel B. Pavlovic, Stacey A. Leicht-Young, Ralph Grundel, Scott A. Weyenberg, Neal Mulconrey

JFSP Research Project Reports

Oriental bittersweet (Celastrus orbiculatus) is an introduced liana (woody vine) that has invaded much of the Eastern United States and is expanding west into the Great Plains. In forests, it can girdle and damage canopy trees. At Indiana Dunes, we have discovered that it is invading non-forested dune habitats as well. Anecdotal evidence suggests that fire might facilitate its spread, but the relationship between fire and this aggressive invader is poorly understood. We investigated four areas important to fire management of oriental bittersweet, each of which we will briefly summarize here. 1) What fire temperatures cause seed mortality? For seeds, …

Wildland Fire Suppression And Land Development In The Wildland/Urban Interface, Sheila Olmstead, Carolyn Kousky, Roger Sedjo

JFSP Research Project Reports

This project has explored the hypothesis that public fire suppression in fire‐prone areas acts as a subsidy to landowners, incentivizing conversion of land to residential and commercial development. Landowners do not bear the full cost of their choice to build on land in fire‐prone areas, since they do not pay for suppression, though they reap all of the benefits, potentially resulting in economically inefficient levels of development. To test this hypothesis, we performed an econometric analysis of U.S. land use change between 1970 and 2000. Statistically, we identified the impacts of changes in fire suppression policy by exploiting a natural …

Wildfire Regime Shifts In Temperate Forest Ecosystems: International Symposium In New Zealand, Tomas Veblen, Alan Tepley, Andres Holz

JFSP Research Project Reports

This project consisted of organizing and executing a one-day symposium on “Wildfire Regime Shifts in Temperate Forest Ecosystems” in conjunction with the triennial meeting of the Southern Connection Congress. The VIIth Southern Connection Congress drew together more than 350 environmental scientists and resource managers for its triennial meeting in Dunedin, New Zealand from January 25 to 30, 2013. The Southern Connection Congress (SCC) is a meeting of interdisciplinary researchers and natural resource managers who are interested in the biota and ecosystems of the temperate latitudes of the southern hemisphere. Attendees are from a wide range of research and professional disciplines …

Using Escaped Prescribed Fire Reviews To Improve Organizational Learning, Anne E. Black Dr., James Saveland Dr., Dave Thomas, Jennifer Ziegler Dr.

JFSP Research Project Reports

The US wildland fire community has been interested in cultivating organizational learning to improve safety and overall performance for a number of years. A key focus has been on understanding the difference between culpability (to be guilty) and accountability (to explain) and on re-orienting review processes towards building a collective account of (as opposed to finding individual blame for) unwanted outcomes. A variety of innovative methodologies have been developed, yet until this project, there has been no systematic reflection to determine whether or how any of the existing review processes might be assisting organizational learning. Through a series of five …

A Fire Prevention Effectiveness Assessment For Multiple Ownerships, Jeffrey P. Prestemon Dr., Karen L. Abt, David T. Butry, Douglas S. Thomas, Sam Scranton, Scott L. Goodrick, Parker T. Mothershead, Terry K. Haimes, Susan Marzec, John Owens, Suzanne Romero, Reid Shelley, Loren Walker, Angela Yearwood

JFSP Research Project Reports

This study first summarized findings of fire prevention education statistical modeling from the State of Florida from a study originally led by the Principal Investigator and two major collaborators (Karen Abt, USDA Forest Service, and David T. Butry, National Institute of Standards and Technology). The study next measured the statistical effects of wildfire prevention programs occurring on tribal lands administered by the Bureau of Indian Affairs, with primary involvement of major collaborator Sam Scranton (Bureau of Indian Affairs). Using first a binary variable indicating the presence or absence of a wildfire prevention program on lands managed by the tribe or …