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Transverse Momentum And Total Cross Section Of E+E- Pairs In The Z-Boson Region, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Jan 2000

Transverse Momentum And Total Cross Section Of E+E- Pairs In The Z-Boson Region, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

The transverse momentum and total cross section of e+e- pairs in the Z-boson region of 66 < Mee < 116 GeV/c2 from pp̅ collisions at √s =1.8 TeV are measured using 110 pb-1 of collisions taken by the Collider Detector at Fermilab during 1992–1995. The total cross section is measured to be 248 ± 11 pb. The differential transverse momentum cross section is compared with calculations that match quantum chromodynamics perturbation theory at high transverse momentum with the gluon resummation formalism at low transverse momentum.

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Measurement Of Inclusive Prompt Photon Photoproduction At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti Jan 2000

Measurement Of Inclusive Prompt Photon Photoproduction At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

© 2000 Published by Elsevier Science B.V. All rights reserved. First inclusive measurements of isolated prompt photons in photoproduction at the HERA ep collider have been made with the ZEUS detector, using an integrated luminosity of 38.4 pb-1. Cross sections are given as a function of the pseudorapidity and the transverse energy (ηγ, Eγ . of the photon, for E>5 GeV in the γ p centre-of-mass energy range T T 134-285 GeV. Comparisons are made with predictions from Monte Carlo models having leading-logarithm parton showers, and with next-To-leading-order QCD calculations, using currently available parameterisations of the photon structure. For …

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Measurement Of The Helicity Of W Bosons In Top Quark Decays, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Jan 2000

Measurement Of The Helicity Of W Bosons In Top Quark Decays, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We use the transverse momentum spectrum of leptons in the decay chain t → bW with W → lν to measure the helicity of the W bosons in the top quark rest frame. Our measurement uses a tt̅ sample isolated in 106 ± 4 pb-1 of data collected in pp̅ collisions at √s = 1.8 TeV with the CDF detector at the Fermilab Tevatron. Assuming a standard V-A weak decay, we find that the fraction of W’s with zero helicity in the top rest frame is F0 = 0.91 ± 0.37(stat)± 0.13(syst), consistent with the standard model …

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Observation Of Diffractive B-Quark Production At The Fermilab Tevatron, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration Jan 2000

Observation Of Diffractive B-Quark Production At The Fermilab Tevatron, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

We report a measurement of the fraction of b quarks produced diffractively in p̅p collisions at √s =1.8 TeV. Diffraction is identified by the absence of particles in a forward pseudorapidity region. From events with an electron of transverse momentum 9.5< pTe /c within the pseudorapidity region |η| < 1.1, the ratio of diffractive to total b-quark production rates is found to be Rbb= [0.62 ± 0.19(stat) ± 0.16(syst)]%. This result is comparable in magnitude to corresponding ratios for W and dijet production but significantly lower than expectations based on factorization.

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W Production And The Search For Events With An Isolated High-Energy Lepton And Missing Transverse Momentum At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti Jan 2000

W Production And The Search For Events With An Isolated High-Energy Lepton And Missing Transverse Momentum At Hera, J. Breitweg, S. Chekanov, M. Derrick, D. Krakauer, S. Magill, B. Musgrave, A. Pellegrino, J. Repond, R. Stanek, R. Yoshida, Margarita C. K. Mattingly, G. Abbiendi, F. Anselmo, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, G. Cara Romeo, G. Castellini, L. Cifarelli, F. Cindolo, A. Contin, N. Coppola, M. Corradi, S. De Pasquale, P. Giusti, G. Iacobucci, G. Laurenti

Faculty Publications

© 2000 Published by Elsevier Science B.V. All rights reserved. A search for the leptonic decays of W bosons produced in the reaction e+ p → e+ W± X at a centre-of-mass energy of 300GeV has been performed with the ZEUS detector at HERA using an integrated luminosity of 47.7 pb-1. Three events consistent with W → eν decay are found, giving a cross section estimate of 0.9+10-07±0.2 pb, in good agreement with the Standard Model prediction. The corresponding 95% C.L. upper limit on the cross section is 3.3 pb. A search for the decay W → μν has a …

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Theoretical Calculations Of Magnetic Order And Anisotropy Energies In Molecular Magnets, M. R. Pederson, D. V. Porezag, J. Kortus, S. N. Khanna Jan 2000

Theoretical Calculations Of Magnetic Order And Anisotropy Energies In Molecular Magnets, M. R. Pederson, D. V. Porezag, J. Kortus, S. N. Khanna

Physics Publications

We present theoretical electronic structure calculations on the nature of electronic states and the magnetic coupling in the Mn12O12 free cluster and the Mn12O12(RCOO)16(H2O)4 molecular magnetic crystal. The calculations have been performed with the all-electron full-potential NRLMOL code. We find that the free Mn12O12cluster relaxes to an antiferromagneticcluster with no net moment. However, when coordinated by sixteen HCOO ligands and four H2O groups, as it is in the molecular crystal, we find that the ferrimagnetic ordering and geometrical and magnetic structure observed in the experiments is restored. Local Mn moments for the free and ligandated molecular magnets are presented and …

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The Optical Depth To Reionization As A Probe Of Cosmological And Astrophysical Parameters, Aparna Venkatesan Jan 2000

The Optical Depth To Reionization As A Probe Of Cosmological And Astrophysical Parameters, Aparna Venkatesan

Physics and Astronomy

Current data of high-redshift absorption-line systems imply that hydrogen reionization occurred before redshifts of about 5. Previous works on reionization by the first stars or quasars have shown that such scenarios are described by a large number of cosmological and astrophysical parameters. Here we adopt a semianalytic model of stellar reionization in order to quantify how the optical depth to reionization depends on such parameters, and combine this with constraints from the cosmic microwave background (CMB). We find this approach to be particularly useful in alleviating the well-known degeneracy in CMB parameter extraction between the optical depth to reionization and …

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Extended Conformal Symmetry, James Thomas Wheeler Jan 2000

Extended Conformal Symmetry, James Thomas Wheeler

All Physics Faculty Publications

We show that the grading of fields by conformal weight, when built into the initial group symmetry, provides a discrete, non-central conformal extension of any group containing dilatations. We find a faithful vector representation of the extended conformal group and show that it has a scale-invariant scalar product and satisfies a closed commutator algebra. The commutator algebra contains the infinite Heisenberg and Virasoro algebras. In contrast to the classical treatment of scale invariance, covariant derivatives and gauge transformations automatically incorporate the correct conformal weights when the extended symmetry is gauged.

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Characterization Of Poly-Si Thin Films Deposited By Magnetron Sputtering Onto Ni Prelayers, Elena A. Guliants, Wayne A. Anderson Jan 2000

Characterization Of Poly-Si Thin Films Deposited By Magnetron Sputtering Onto Ni Prelayers, Elena A. Guliants, Wayne A. Anderson

Electrical and Computer Engineering Faculty Publications

A method of producing a polycrystalline silicon thin film on a foreign substrate without subsequent annealing has been developed. Thermally evaporated 5–100 nm thick Nifilms served as prelayers for magnetron sputtered Si thin films. A continuous film was obtained as a result of metal induced growth of polysilicon during low temperature (below 600 °C) deposition. The film uniformity is promising for large area device applications. The influence of the Ni prelayer thickness on the grain size of thus obtained films was investigated. Atomic force microscopy and cross-sectional scanning electron microscopy studies revealed features in the 150–600 nm size range while …

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Magnetic Coupling In Neutral And Charged Cr-2, Mn-2, And Crmn Dimers, N. Desmarais, F. A. Reuse, S. N. Khanna Jan 2000

Magnetic Coupling In Neutral And Charged Cr-2, Mn-2, And Crmn Dimers, N. Desmarais, F. A. Reuse, S. N. Khanna

Physics Publications

Theoreticalab initio studies of neutral, cationic and anionic Cr2, Mn2, and CrMn dimers have been carried out to explore the progression of magnetic coupling with the number of electrons. It is shown that while Cr2 and Cr−2 have antiferromagnetically coupled atomic spins, Cr+2 has a ferromagneticground state closely followed by an antiferromagnetic state. On the other hand, all Mn2 dimers are ferromagnetic, irrespective of the charge. The neutral CrMn is ferrimagnetic while the charged CrMn are antiferromagnetic. In all cases, the charged dimers are found to be more stable than the neutral ones. The results are compared with available …

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On The Bosonic Spectrum Of Qcd (1+1) With Su(N) Currents, Uwe Trittmann Jan 2000

On The Bosonic Spectrum Of Qcd (1+1) With Su(N) Currents, Uwe Trittmann

Physics Faculty Scholarship

In this note we calculate the spectrum of two-dimensional QCD. We formulate the theory with SU(Nc) currents rather than with fermionic operators. We construct the Hamiltonian matrix in DLCQ formulation as a function of the harmonic resolution K and the numbers of flavors N f and colors N c.The resulting numerical eigenvalue spectrum is free from trivial multi-particle states which obscured previous results. The well-known ’t Hooft and large N f spectra are reproduced. In the case of adjoint fermions we present some new results.

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Experimental And Theoretical Study Of The Photoelectron Spectra Of Mnox-(X=1-3) Clusters, Gennady L. Gutsev, B. K. Rao, P. Jena, Xi Li, Lai-Sheng Wang Jan 2000

Experimental And Theoretical Study Of The Photoelectron Spectra Of Mnox-(X=1-3) Clusters, Gennady L. Gutsev, B. K. Rao, P. Jena, Xi Li, Lai-Sheng Wang

Physics Publications

We report a combined experimental and theoretical investigation of MnO−x and MnOx(x=1–3) clusters. Theoretically, geometrical configurations of various isomers of the clusters were optimized and vertical detachment energies for the anions were evaluated. The ground state of MnO− was predicted to be 5Σ+, followed by an excited state (7Σ+) 0.14 eV higher in energy. The ground state of MnO−2 is 5B2, with a 3B1 isomer 0.15 eV higher. MnO−3 is predicted to be a singlet D3h cluster. Vibrationally resolved photoelectron spectra of MnO−x were measured at several photon energies and under various experimental conditions, and were interpreted based on the …

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Using Binary Star Observations To Bound The Mass Of The Graviton, Shane L. Larson, William A. Hiscock Jan 2000

Using Binary Star Observations To Bound The Mass Of The Graviton, Shane L. Larson, William A. Hiscock

All Physics Faculty Publications

Interacting white dwarf binary star systems, including helium cataclysmic variable (HeCV) systems, are expected to be strong sources of gravitational radiation, and should be detectable by proposed space-based laser interferometer gravitational wave observatories such as LISA. Several HeCV star systems are presently known and can be studied optically, which will allow electromagnetic and gravitational wave observations to be correlated. Comparisons of the phases of a gravitational wave signal and the orbital light curve from an interacting binary white dwarf star system can be used to bound the mass of the graviton. Observations of typical HeCV systems by LISA could potentially …

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Effects Of Evolving Surface Contamination On Spacecraft Charging, W. Y. Chang, John R. Dennison, Jason Kite, R. E. Davies Jan 2000

Effects Of Evolving Surface Contamination On Spacecraft Charging, W. Y. Chang, John R. Dennison, Jason Kite, R. E. Davies

All Physics Faculty Publications

The effects of evolving surface contamination on spacecraft charging have been investigated through (i) ground-based measurements of the change in electron emission properties of a conducting surface undergoing contamination and (ii) modeling of the charging of such surfaces using the NASCAP code. Specifically, we studied a Au surface as adsorbed species were removed and a very thin disordered carbon film was deposited as a result of exposure to an intense, normal incidence electron beam. As a result of this contamination, we found an ~50% decrease in secondary electron yield and an ~20% reduction in backscattered yield. The type and rates …

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Sensitivity Curves For Spaceborne Gravitational Wave Interferometers, Shane L. Larson, William A. Hiscock, Ronald W. Hellings Jan 2000

Sensitivity Curves For Spaceborne Gravitational Wave Interferometers, Shane L. Larson, William A. Hiscock, Ronald W. Hellings

All Physics Faculty Publications

To determine whether particular sources of gravitational radiation will be detectable by a specific gravitational wave detector, it is necessary to know the sensitivity limits of the instrument. These instrumental sensitivities are often depicted (after averaging over source position and polarization) by graphing the minimal values of the gravitational wave amplitude detectable by the instrument versus the frequency of the gravitational wave. This paper describes in detail how to compute such a sensitivity curve given a set of specifications for a spaceborne laser interferometer gravitational wave observatory. Minor errors in the prior literature are corrected, and the first (mostly) analytic …

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Renormalons As Dilation Modes In The Functional Space, A. Babansky, I. Balitsky Jan 2000

Renormalons As Dilation Modes In The Functional Space, A. Babansky, I. Balitsky

Physics Faculty Publications

There are two possible sources of the factorial large-order behavior of a typical perturbative series. First, the number of different Feynman diagrams may be large; second, there may be abnormally large diagrams known as renormalons. It is well known that the large combinatorial number of diagrams is described by instanton-type solutions of the classical equations. We demonstrate that, from the functional-integral viewpoint, the renormalons do not correspond to a particular configuration but manifest themselves as dilatation modes in the functional space.

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High Energy Effective Action From Scattering Of Shock Waves In Qcd, Ian Balitsky Jan 2000

High Energy Effective Action From Scattering Of Shock Waves In Qcd, Ian Balitsky

Physics Faculty Publications

The author demonstrates that the amplitude for high-energy scattering can be factorized as a convolution of the contributions due to fast and slow fields. The fast and slow fields interact by means of Wilson-line operators -- infinite gauge factors ordered along the straight line. The resulting factorization formula gives a starting point for a new approach to the effective action for high-energy scattering in QCD.

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Robust Test For Detecting Nonstationarity In Data From Gravitational Wave Detectors, Soumya Mohanty Jan 2000

Robust Test For Detecting Nonstationarity In Data From Gravitational Wave Detectors, Soumya Mohanty

Physics & Astronomy Faculty Publications

It is difficult to choose detection thresholds for tests of nonstationarity that assume a priori a noise model if the data are statistically uncharacterized to begin with. This is a potentially serious problem when an automated analysis is required, as would be the case for the huge data sets that large interferometric gravitational wave detectors will produce. A solution is proposed in the form of a robust time-frequency test for detecting nonstationarity whose threshold for a specified false alarm rate is almost independent of the statistical nature of the ambient stationary noise. The efficiency of this test in detecting bursts …

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Optical Performance Of Grazing Incidence X-Ray / Euv Telescopes For Space Science Applications, Patrick Louis Thompson Jan 2000

Optical Performance Of Grazing Incidence X-Ray / Euv Telescopes For Space Science Applications, Patrick Louis Thompson

Retrospective Theses and Dissertations

The science and technology of X-rays has only been part of human achievement for the past 100 years, while the study of image formation in general has endured for as long as 1000 years. The ability to conceive, design, and fabricate X-ray imagers, moreover, has existed for only the past 70 years, and X-ray astronomical telescopes have been in use for a mere 35 years. Considering that aplanatic, normal incidence telescope designs required more than 400 years to perfect, it is most interesting to note that the development of ‘aplanatic’ grazing incidence telescopes has taken only about 40 years. In …

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Erratum: "Cell Size Dependence Of Transport Coefficients In Stochastic Particle Algorithms", Alejandro Garcia, F. Alexander, B. Alder Jan 2000

Erratum: "Cell Size Dependence Of Transport Coefficients In Stochastic Particle Algorithms", Alejandro Garcia, F. Alexander, B. Alder

Faculty Publications

No abstract provided.

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Gender And Physical Science: A Hard Look At A Hard Science, Amy Lisa Graves Jan 2000

Gender And Physical Science: A Hard Look At A Hard Science, Amy Lisa Graves

Physics & Astronomy Faculty Works

No abstract provided.

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Beyond The Dipole Approximation: Angular-Distribution Effects In The 1s Photoemission From Small Molecules, Dennis W. Lindle, Oliver Hemmers, H. Wang, P. Focke, I. A. Sellin, J. D. Mills, J. A. Sheehy, P. W. Langhoff Jan 2000

Beyond The Dipole Approximation: Angular-Distribution Effects In The 1s Photoemission From Small Molecules, Dennis W. Lindle, Oliver Hemmers, H. Wang, P. Focke, I. A. Sellin, J. D. Mills, J. A. Sheehy, P. W. Langhoff

Environmental Studies Faculty Publications

Over the past two decades, the dipole approximation has facilitated a basic understanding of the photoionization process in atoms and molecules. Recent experiments on the 1s inner shells of small molecules at relatively low photon energies (⩽ 1000 eV) show strong nondipole effects. They are significant and measurable at energies close to threshold, in conflict with a common assumption that the dipole approximation is valid for photon energies below 1 keV.

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Rotary Honing: A Variant Of The Taylor Paint-Scraper Problem, Christopher Hills, H. Moffatt Jan 2000

Rotary Honing: A Variant Of The Taylor Paint-Scraper Problem, Christopher Hills, H. Moffatt

Articles

The three-dimensional Row in a corner of fixed angle α induced by the rotation in its plane of one of the boundaries is considered. A local similarity solution valid in a neighbourhood of the centre of rotation is obtained and the streamlines are shown to be closed curves. The effects of inertia are considered and are shown to be significant in a small neighbourhood of the plane of symmetry of the flow. A simple experiment confirms that the streamlines are indeed nearly closed; their projections on planes normal to the line of intersection of the boundaries are precisely the 'Taylor' …

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The Effect Of Various Experimental Parameters On Glow Peaks And Trapping Parameters Of Caf_2:Dy (Tld-200) Crystals, A. Necmeddi̇n Yazici, M. Yakup Hacii̇brahi̇moğlu, Meti̇n Bedi̇r Jan 2000

The Effect Of Various Experimental Parameters On Glow Peaks And Trapping Parameters Of Caf_2:Dy (Tld-200) Crystals, A. Necmeddi̇n Yazici, M. Yakup Hacii̇brahi̇moğlu, Meti̇n Bedi̇r

Turkish Journal of Physics

In the present study, thermoluminescence glow curves of CaF$_{2}$:Dy (TLD-200) crystals have been investigated in detail between the temperature region 300-550 K. The number of peaks and their trapping parameters (E, s and b) have been determined using the computerized glow curve fitting, peak shape and isothermal decay methods. In addition, the effect of storage times at room temperature, dose levels and heating rates on the trapping parameters have been investigated in detail by using computerized glow curve deconvolution method (CGCD) using first and general order kinetic equations.

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Mirroring And Mimicking Of Partial Cross Sections In The Vicinity Of A Resonance, Chien-Nan Liu, Anthony F. Starace Jan 2000

Mirroring And Mimicking Of Partial Cross Sections In The Vicinity Of A Resonance, Chien-Nan Liu, Anthony F. Starace

Anthony F. Starace Publications

We review recent analytical work on mirroring and mimicking behavior of resonance profiles in different partial cross sections. This work is related to the work of Fano and Cooper on resonance profiles in total cross sections and that of Starace on resonance profiles in partial cross sections. Applications of the new theories (describing mirroring and mimicking behavior) to recent experimental measurements and theoretical predictions for photoionization, photodetachment, and Auger spectroscopy in the vicinity of resonance structures are discussed.

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Magnetic Confinement, Magnetohydrodynamic Waves And Smooth Line Profiles In Active Galactic Nuclei, M. C. Bottorff, Gary J. Ferland Jan 2000

Magnetic Confinement, Magnetohydrodynamic Waves And Smooth Line Profiles In Active Galactic Nuclei, M. C. Bottorff, Gary J. Ferland

Physics and Astronomy Faculty Publications

In this paper, we show that if the broad-line region clouds are in approximate energy equipartition between the magnetic field and gravity, as hypothesized by Rees, there will be a significant effect on the shape and smoothness of broad emission-line profiles in active galactic nuclei. Linewidths of contributing clouds or flow elements are much wider than their thermal widths, because of the presence of non-dissipative magnetohydrodynamic waves and their collective contribution produce emission-line profiles broader and smoother than would be expected if a magnetic field were not present. As an illustration, a simple model of isotropically emitting clouds, normally distributed …

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The Lattice Dynamics Of Bcc Titanium, Kemal Çolakoğlu, Yasemi̇n Özteki̇n Çi̇ftçi̇ Jan 2000

The Lattice Dynamics Of Bcc Titanium, Kemal Çolakoğlu, Yasemi̇n Özteki̇n Çi̇ftçi̇

Turkish Journal of Physics

Using in measurements of the phonon frequencies of bcc Titanium, the lattice dynamical calculations are performed on the same phase by using the Third-neighbour Clark-Gazis-Wallis(CGW) model. The theory is used to compute the phonon dispersion curves, the frequency spectra and the lattice spesific heat of the studied phase. The obtained results are compared with the available experimental data.

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Causal Implications Of Viscous Damping In Compressible Fluid Flows, P. M. Jordan, Martin R. Meyer, Ashok Puri Jan 2000

Causal Implications Of Viscous Damping In Compressible Fluid Flows, P. M. Jordan, Martin R. Meyer, Ashok Puri

Physics Faculty Publications

Classically, a compressible, isothermal, viscous fluid is regarded as a mathematical continuum and its motion is governed by the linearized continuity, Navier-Stokes, and state equations. Unfortunately, solutions of this system are of a diffusive nature and hence do not satisfy causality. However, in the case of a half-space of fluid set to motion by a harmonically vibrating plate the classical equation of motion can, under suitable conditions, be approximated by the damped wave equation. Since this equation is hyperbolic, the resulting solutions satisfy causal requirements. In this work the Laplace transform and other analytical and numerical tools are used to …

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K-Vacancy Production In The Collision Of Highly Charged Relativistic Ions With Heavy Atoms, P. K. Khabibullaev, V. I. Matveev, D. U. Matrasulov Jan 2000

K-Vacancy Production In The Collision Of Highly Charged Relativistic Ions With Heavy Atoms, P. K. Khabibullaev, V. I. Matveev, D. U. Matrasulov

Turkish Journal of Physics

A general expression for the cross section of the inelastic collision of relativistic highly charged ion with heavy (relativistic) atoms is obtained using the generalized eikonal approximation. In the ultrarelativistic limit, the obtained formula coincides with a known exact one. As an application of the obtained result, probability and cross section of the K-vacany production in the $U^{92+} - U^{91+}$ collision are calculated.

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High Magnetic Field Corrections To Resistance Thermometers For Low Temperature Calorimetry, Nathanael Fortune, Gayle Gossett, Lydia Peabody, Katherine Lehe, S. Uji, H. Aoki Jan 2000

High Magnetic Field Corrections To Resistance Thermometers For Low Temperature Calorimetry, Nathanael Fortune, Gayle Gossett, Lydia Peabody, Katherine Lehe, S. Uji, H. Aoki

Physics: Faculty Publications

We present a general analytical method of correcting for magnetic-field-induced changes in both the apparent temperature and the sensitivity of resistive thermometers at dilution refrigerator temperatures. With this method, we are able to reduce magnetic field induced errors in temperature to a level limited only by our ability to regulate the temperature in the absence of a magnetic field. We illustrate the application of our method to two resistive sensors in magnetic fields up to 18 T: a custom-made AuxGe1-x thin film sensor used in calorimetry and a commercially available ruthenium-oxide thick film resistor used in thermometry.

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