## MEASURING DISTANCES IN ASTRONOMY Basic Principles: Geometric methods St in addition to ard ca

Swift, Ron, Freelance Columnist has reference to this Academic Journal, PHwiki organized this Journal MEASURING DISTANCES IN ASTRONOMY Basic Principles: Geometric methods St in addition to ard c in addition to les St in addition to ard rulers [the last two methods relate quantities that are independent of distance to quantities that depend on distance] Parallax in addition to Proper Motion Angular size: degree [º], arcminute [‘], arcsecond [“] [in arcseconds] = 206265 (L/D) where: = angular size; L = linear (or true) size; D = distance Definitions: parallax (p), Astronomical Unit [AU], parsec [pc] D [in parsec] = 1/p [in arcseconds] where: 1 pc = 206265 AU = 3.26 light yr Parallax can only be used on nearby stars (D < 100 pc) [Atmospheric blurring (seeing); Hipparcos satellite; Hubble Space Telescope]

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Motion of stars within a cluster Proper motion [arcsec/s] = change of angular position Line-of-sight motion [km/s] – measured via Doppler shift Comparison of average stellar proper motion in cluster with average line-of-sight speed yields distance to cluster Luminosity in addition to Flux Inverse square law: f = L / (4D2) where: f = flux [erg/s/cm2]; L = luminosity [erg/s]; D = distance [cm] Magnitude scale: brightnesses of astronomical sources

St in addition to ard C in addition to les in addition to Rulers Variable stars: Cepheids in addition to RR Lyrae stars Period-luminosity relation; measure P & infer L; measure f & infer D Other st in addition to ard c in addition to les: brightest red giants, HII regions, planetary nebulae, supernovae, globular cluster luminosity Galaxies: Luminosity is seen to be correlated with the typical speed of internal motion of stars in addition to gas [Tully-Fisher relation: rotation of disks of spiral galaxies] [Faber-Jackson relation: r in addition to om stellar motion in elliptical galaxies] Galaxies: Size correlated with typical speed of (r in addition to om) stellar motion [Dn- relation as long as elliptical galaxies] Redshift as Distance Indicator Expansion of the Universe Hubble’s law: v = H0 D where: H0 = Hubble constant [km/s/Mpc] Doppler shift used to measure recession velocity: v c ( / ) where: / = fractional change in wavelength Astronomical Distance Ladder

Special Theory of Relativity (STR) Speed of light (in vacuum): c = 300,000 km/s Constancy of the speed of light: Michelson & Morley experiment No signal or object can travel faster than c [The ultimate speed limit!] Special Theory of Relativity (STR) Basic Principles The speed of light is the same to all observers The laws of physics are the same to all observers Observable Consequences Simultaneity is a relative concept Length contraction: moving rulers appear to be short Time dilation: moving clocks appear to run slow The apparent mass (inertia) of an object increases as its speed increases (impossible to accelerate it up to c) Equivalence of mass in addition to energy: E = mc2 Special relativistic effects are important when the SPEED of an object is CLOSE TO THE SPEED OF LIGHT: v c

Simultaneity in addition to time are relative, not absolute Marion Jones sees A flash be as long as e B Marion Jones sees A in addition to B flash simultaneously Measuring the length of a moving object: Length Contraction The apparent (i.e., measured) length of a moving object is shorter than the true length (measured when the object is at rest) Measuring time on a moving clock: Time Dilation A moving clock runs slower than its counterpart at rest Stationary Clock Moving Clock

A Thought Experiment: Length Contraction in addition to an Apparent Paradox The Garage Attendants Perspective A Thought Experiment: Length Contraction in addition to an Apparent Paradox The Drivers Perspective Solution: The driver in addition to garage attendant do not agree on the question of whether the two doors were closed simultaneously A Real Laboratory Experiment: Direct Verification of Time Dilation in addition to Length Contraction as Predicted by the Special Theory of Relativity The scientist in the laboratory witnesses time dilation, while the Uranium atoms witness length contraction Beam of fast-moving Uranium atoms Suitably placed Geiger counter Nuclear fission of Uranium atoms

General Theory of Relativity (GTR) Principle of Equivalence All objects experience the same motion in a given gravitational field, irrespective of their mass [Galileo’s experiment at the leaning tower of Pisa] Gravitational field <===> Accelerated reference frame Gravity can be thought of as a distortion of space-time Observable Consequences of GTR Perihelion precession of Mercury Light bending: Solar eclipse experiment

Gravitational lensing: Multiple images, image distortion Gravitational Redshift [Extreme case: light is trapped in a black hole] General relativistic effects are important in a STRONG GRAVITATIONAL FIELD

## Swift, Ron Freelance Columnist

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## The physics of the InternetWhy SOC/EOC/ models failA network based explanation Heavy tails in networks

Sutton, Marsha, Freelance Columnist has reference to this Academic Journal, PHwiki organized this Journal Notices of the AMS, September 1998 Internet traffic St in addition to ard Poisson models dont capture long-range correlations. Poisson Measured Internet traffic Fractional Gaussian (fractal) noise models measurements well. Hurst parameter H is an aggregate measure of long-range correlations. Fractal Measured

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The physics of the Internet Physicists use chaos to calm the web, (Physics World, 2001) www.networkphysics.com Large literature in physics journals in addition to recently in Science, Nature, etc Links The SOC (Self-Organized Criticality) view Links Flow capacity Average Queue phase transition

Lattice without congestion control (!) Critical phase transition at max capacity At criticality: self-similar fluctuations, long tailed queues in addition to latencies, 1/f time series, etc Alternative edge of chaos models Self-similarity due to chaos in addition to independent of higher-layer characteristics Why SOC/EOC/ models fail No critical traffic rate Self-similar scaling at all different rates TCP can be unstable in addition to perhaps chaotic, but does not generate self-similar scaling Self-similar scaling occurs in all as long as ms of traffic (TCP in addition to nonTCP) Measured traffic is not consistent with these models Fractal in addition to scale-free topology models are equally specious ( as long as different reasons)

A network based explanation Underlying cause: If connections arrive r in addition to omly (in time) in addition to if their size ( packets) have high variability (i.e. are heavy-tailed with infinite variance) then the aggregate traffic is per as long as ce self-similar Evidence Coherent in addition to mathematically rigorous framework Alternative measurements (e.g. TCP connections, IP flows) Alternative analysis (e.g. heavy-tailed property) Typical web traffic log(file size) > 1.0 log(freq > size) p s- Web servers Heavy tailed web traffic Is streamed out on the net. Creating fractal Gaussian internet traffic (Willinger, ) Fat tail web traffic Is streamed onto the Internet creating long-range correlations with time

Heavy tails in addition to divergent length scales are everywhere in networks. There is a large literature since 1994: Lel in addition to , Taqqu, Willinger, Wilson Paxson, Floyd Crovella, Bestavros Harchol-Balter, Heavy tails in networks Typical web traffic log(file size) > 1.0 log(freq > size) p s- Web servers Heavy tailed web traffic Is streamed out on the net. Piece of a consistent, rigorous theory with supporting measurements

## Sutton, Marsha Freelance Columnist

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## Earth Science Summaries by Edward J. Tarbuck Frederick K. Lutgens SOURCE: http:/

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Earth science is the name as long as all the sciences that collectively seek to underst in addition to Earth in addition to its neighbors in space. It includes geology, oceanography, meteorology, in addition to astronomy. Geology is traditionally divided into two broad areasphysical in addition to historical.

Environment refers to everything that surrounds in addition to influences an organism. These influences can be biological, social, or physical. When applied to Earth science today, the term environmental is usually reserved as long as those aspects that focus on the relationships between people in addition to the natural environment.

Resources are an important environmental concern. The two broad categories of resources are (1) renewable, which means that they can be replenished over relatively short time spans, in addition to (2) nonrenewable. As population grows, the dem in addition to as long as resources exp in addition to s as well.

Environmental problems can be local, regional, or global. Human-induced problems include urban air pollution, acid rain, ozone depletion, in addition to global warming. Natural hazards include earthquakes, l in addition to slides, floods, in addition to hurricanes.

As world population grows, pressures on the environment also increase. All science is based on the assumption that the natural world behaves in a consistent in addition to predictable manner. The process by which scientists gather facts through observation in addition to careful measurement in addition to as long as mulate scientific hypotheses in addition to theories is called the scientific method.

To determine what is occurring in the natural world, scientists often (1) collect facts, (2) develop a scientific hypothesis, (3) construct experiments to validate the hypothesis, in addition to (4) accept, modify, or reject the hypothesis on the basis of extensive testing. Other discoveries represent purely theoretical ideas that have stood up to extensive examination. Still other scientific advancements have been made when a totally unexpected happening occurred during an experiment.

One of the challenges as long as those who study Earth is the great variety of space in addition to time scales. The geologic time scale subdivides the 4.5 billion years of Earth history into various units. The nebular hypothesis describes the as long as mation of the solar system.

The planets in addition to Sun began as long as ming about 5 billion years ago from a large cloud of dust in addition to gases. As the cloud contracted, it began to rotate in addition to assume a disk shape. Material that was gravitationally pulled toward the center became the protosun.

Within the rotating disk, small centers, called protoplanets, swept up more in addition to more of the cloud’s debris. Because of their high temperatures in addition to weak gravitational fields, the inner planets were unable to accumulate in addition to retain many of the lighter components. Because of the very cold temperatures existing far from the Sun, the large outer planets consist of huge amounts of lighter materials.

Almost 14 billion years ago, a cataclysmic explosion hurled this material in all directions, creating all matter in addition to space. Eventually the ejected masses of gas cooled in addition to condensed, as long as ming the stellar systems we now observe fleeing from their place of origin.

## Stossel, John Freelance Columnist

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## This composite image of sunspot group was collected with the Dunn solar telescop

Regan, Gary, Freelance Columnist has reference to this Academic Journal, PHwiki organized this Journal This composite image of sunspot group was collected with the Dunn solar telescope at the Sacramento Peak Observatory in New Mexico on Mar. 29, 2001. The lower portion, consisting of four frames, was collected at a wavelength of 293.4 nm. The upper portion was collected at 430.4 nm. The lower image represents calcium ion concentration, with the intensity of color proportional to the amount of calcium ion in the sunspot. The upper image shows the presence of the CH molecule. Richard P. Feynman (1918~1988) was one of the most well-known in addition to renowned scientists of the 20th century. He was awarded the Nobel Prize in Physics in 1965. Spectrophotometry Spectroscopy : the science that deals with the interaction of electromagnetic radiation with matter. Spectrometry : a more restrictive term, denotes the quantitative measurement of the intensity of electromagnetic radiation at one or more wavelengths with photoelectric detector. Spectrum (pl. spectra) : a display of the intensity of radiation emitted, absorbed, or scattered by a sample versus a quantity related to photon energy(E), such as wave length() or frequency(). wave length(, nm) or frequency(, cm1). Intensity Spectrum

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Absorption spectra of Fe(III)-salicylic acid complex. UV-visible absorption spectra of cefazolin antibiotics. Plane-polarized electromagnetic radiation showing the electric field, in addition to the direction of propagation. Electric field component of plane-polarized electromagnetic radiation. Properties of light : Electromagnetic radiation ; EM wave ; radiation ; radient ray ; ray ; light Duality ; 1) Wave theory — Huygens = c wavelength (cm/cycle) × frequency (cycles/sec) = velocity (cm/sec) where wavelength, , is the length per unit cycle. Frequency, , is the number of cycles per unit time. C = 2.99792458 × 108 m/s is speed of light 2) Particle (energy packets ; photon) theory — Newton E = h = hc / where E is the energy in joules (J) h is Plancks constant (6.62608 × 10  34 J s) 1 erg = 10 7 J 1 eV = 1.6021 × 10  19 J

Wave number, , is the number of cycles per unit length, cm. = 1 / = cm  1 (reciprocal centimeter ; Kayser) = / c = E / hc Ex. 400 nm x eV E = h = hc / 6.63 10  34 J s 3.00 108 m s  1 = 400 10  9 m 1.6 10  19 J/eV = 3.1 eV Change in wavelength as radiation passes from air into a dense glass in addition to back to air. Note that the wavelength shortens by nearly 200 nm, or more than 30%, as it passes into glass; a reverse change occurs as the radiation again enters air.

Regions of EM spectrum Designation Wavelength Energy or Transition range wave number Cosmic ray -ray X-ray Vacuum UV near UV Visible Near IR Middle IR Far IR Microwave Radio wave 10  12 m 10  11 m >2.5 105 eV 10  8 m 124 eV 180 10  9 m 7 eV 380 10  9 m 3.3 eV 780 10  9 m 1.6 eV 2500 10  9 m 4000 cm  1 50 10  6 m 200 cm  1 10  3 m 10 cm  1 0.3 m Nuclear K,L shell electron Middle shell Valence electron Molecular electron Molecular vibration Molecular vibration Molecular rotation Molecular rotation Electron, & nuclear spin The visible spectrum Wavelength Color absorbed Color observed (nm) (complement) 380-420 Violet Green-yellow 420-440 Violet-blue Yellow 440-470 Blue Orange 470-500 Blue-green Red 500-520 Green Purple 520-550 Yellow-green Violet 550-580 Yellow Violet-blue 580-620 Orange Blue 620-680 Red Blue-green 680-780 Purple Green ROYG RIV Red, Orange, Yellow, Green, Blue, Indigo, Violet

Absorption methods. Photoluminescence methods. Emission or chemiluminescence processes. Absorption of EM radiation Sun Eye Visual center Source Monochromator Cuvet Detector P0 P b C Incident light P P  dP db b b = 0 b = b Emerging light Molar concentration [C] Absorption of EM radiation

Color of a solution. White light from a lamp or the sun strikes the solution of Fe(SCN)2+. The fairly broad absorption spectrum shows a maximum absorbance in the 460 to 500 nm range. The complementary red color is transmitted. Attenuation of a beam of radiation by an absorbing solution. Reflection in addition to scattering losses with a solution contained in a typical glass cell. Absorption methods. Radiation of incident power 0 can be absorbed by the analyte producing a beam of diminished transmitted power (a) if the frequency of the incident beam, 2 corresponds to energy difference, E1 or E2 (b). The spectrum is shown in (c). Sample Incident radiation 0 Transmitted radiation (a) 2 1 0 E2 = h2 = hc/2 E1 = h1 = hc/1 (b) A 2 1 0 (c)

Lambert Beers law Transmittance T = P / P0 %T = (P / P0) 100 Absorbance (A, O.D., E, As) A = log T = log P/ P0 Lamberts law Lambert in addition to Bouger found that the intensity of the transmitted energy decrease exponentially as the depth (b ; path length of the beam through the sample) increases. dP = k P db dP/P = k db dP/P = k db ln P/P0 = k b log P/P0 = (k/2.303) b A = log P/P0 = (/2.303) b T A Path length Path length Effect of path length on transmittance in addition to absorbance of light. Beers law Beer in 1852 found that concentration (C) is a reciprocal exponential function of transmittance in addition to absorbance is directly proportional to the concentration. dP = P dC dP/P = dC dP/P = dC ln P/P0 = C log P/P0 = (/2.303) C A = log P/P0 = (/2.303) C Lambert – Beers law A = bC where is molar absorptivity Effect of concentration of analyte on transmittance in addition to absorbance of light. A [C] [C] log T Limitation Beers law 1. Concentration deviation ; A = log T = log P/P0 = bC (Eq 1) (0.434 / T) dT = b dC (Eq 2) Eq 2 ÷ Eq 1 (0.434 / T) dT log T dC / C = ÷ b b = (0.434 / T log T) dT C/C = (0.434 / T log T) T A [C] 4 2 1 C/C Twyman Lothian curve T = 36.8 % A = 0.434 normal working range15%T(0.824A)~80%T(0.097A)

2. Refractive index deviation A = bC [ n / (n2 + 2)2] where n is refractive index 3. Instrumental deviation ; difficult to select single wavelength beam max The effect of polychromatic radiation on Beers law. Choosing wavelength in addition to monochromator b in addition to width.Increasing the monochromator b in addition to width broadens the b in addition to s in addition to decreases the apparent absorbance. Absorbance error introduced by different levels of stray light. Deviation from Beers law caused by various levels of stray light.

Chemical deviation from Beers law as long as unbuffered solution of the Indicator HIn. 4. Chemical deviation ; dissociation or reaction with solvent ex. Acidic as long as m intermediate as long as m basic as long as m 5. Solvent deviation T = tsolution / tsolvent 6. Temperature ; narrower spectrum b in addition to at below 50C 7. Pressure ; gas phase sample Errors in spectrophotometric measurements due to instrumental electrical noise in addition to cell positioning imprecision. Typical visible absorption spectra of 1,2,4,5-tetrazine in different solvent. Absorption spectra of KMnO4

## Regan, Gary Freelance Columnist

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## Eelectric Energy Harvesting Through Piezoelectric Polymers Formal Design Review Presentation Overview Objective PVDF- Poly(vinylidene fluoride) Piezoelectric PVDF

Pramuk, Bill, Freelance Columnist has reference to this Academic Journal, PHwiki organized this Journal Eelectric Energy Harvesting Through Piezoelectric Polymers Formal Design Review Don Jenket, II Kathy Li Peter Stone Presentation Overview Project Goals Choice of Materials Choice of Processing Techniques Device Architecture Future Tests Revised Timeline Objective DARPA Objective: Convert mechanical energy from a fluid medium into electrical energy. Fluid flow creates oscillations in an eel body Creates strain energy that is converted to AC electrical output by piezoelectric polymers AC output is stored in addition to /or utilized 3.082 Objective: Harness enough power from air flow to operate a L.E.D.

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PVDF- Poly(vinylidene fluoride) C C H H F F n Properties Chemically Inert Flexible High Mechanical Strength Production React HF in addition to methylchloro as long as m in a refrigerant gas Polymerization from emulsion or suspension by free radical vinyl polymerization References: , Accessed on: 3-9-04; Piezoelectric SOLEF PVDF Films. K-Tech Corp., 1993. Piezoelectric PVDF Molecular Origin Fluorine atoms draw electronic density away from carbon in addition to towards themselves Leads to strong dipoles in C-F bonds Piezoelectric Model of PVDF (Davis 1978) Piezoelectric activity based upon dipole orientation within crystalline phase of polymer Need a polar crystal as long as m as long as permanent polarization Reference: Davis, G.T., Mckinney, J.E., Broadhurst, M.G., Roth, S.C. Electric-filed-induced phase changes in poly(vinylidene fluoride). Journal of Applied Physics 49(10), October, 1978. b-phase (piezoelectric) a-phase (anti-parallel dipoles) Piezoelectric PVDF Poled by the Bauer Process Biaxially stretch film: Orients some crystallites with their polar axis normal to the film Application of a strong electric field across the thickness of the film coordinates polarity Produces high volume fractions of b-phase crystallites uni as long as mly throughout the poled material Selected Properties of 40 mm thick bioriented PVDF Table courtesy of K-Tech Corporation Reference: Piezoelectric SOLEF PVDF Films. K-Tech Corp., 1993.

Tensile Testing of PVDF Cross-sectional Area of the Film Tested: 1 cm X 40 microns = 4 X 10-7 m2 Measured strain: .063 Force at .063 strain: 3.95 lbs. Elastic Modulus Calculated: 2.56 GPa E = s e-1 Clamp Rubber PVDF Electrodes in addition to Wires Desired Properties Electrodes High Conductivity Flexibility Wont oxidize Wires Ease of Attachment Flexibility The Process Attach Electrodes using RF Magnetron Sputtering Sputter 40 nm thick Gold electrodes on sample Attach 3 mil copper wire with silver paste Schematic of Sputtering Vacuum Pump Vacuum Pump Main Chamber Load-Lock Chamber Sample Holder; Sample faces down Sample Holder Rotates Sputter Guns Load-Lock Arm Adapted From: Twisselmann, Douglas J. The Origins of Substrate-Topography-Induced Magnetic Anisotropy in Sputered Cobalt Alloy Films. MIT Doctoral Thesis, February, 2001

Sputtering Apparatus Load-Lock Chamber Vacuum Pump Main Chamber Sample Holder Sputtering Target Eel Tail Schematic Top View Side View Front View Cu Wire 6-10 cm 2 cm 6-10 cm 2 cm 0.04 mm Cu Wire Silver paste Gold Electrode

Air Flow Testing of Eel Tail For cost purposes, used unpoled PVDF Thickness of PVDF film: 74 mm. Can visually inspect eel oscillations Wave as long as ms Estimate flexure in addition to strain Tested 2 cm by {5,6,7,8,9,10} cm tails Fan PVDF Copper Fin Length= 5-10 cm 2 cm Air Flow Testing of Eel Tail 2cm x 6cm PVDF Air Flow Testing of Eel Tail 2cm x 10cm PVDF

Piezoelectric Response in Air Flow 2cm x 6cm Piezoelectric PVDF Estimation of Piezoelectric Response V = 3/8 (t/L)2 h31 dz, t= thickness; L = Length; dz = bending radius in addition to h31 = g31(c11 + c12)+ g33c13 g31 = 610-12/11eo [Vm/N] c11 = 3.7 GNm-2 L = 6 cm g33 = -0.14 [Vm/N] c12 = 1.47 GNm-2 t = 40 mm dz = 3 cm c13 = 1.23 GNm-2 Equation taken from: Herbert, J.M., Moulson, A.J. Electroceramics: Materials, Properties, Applications. Chapman in addition to Hall: London, 1990. Piezoelectric Constants taken from: Roh, Y. et al. Characterization of All the Electic, Dielectric in addition to Piezoelectric Constants of uniaxially oriented poled PVDF films. IEEE Transactions on Ultrasonics, Ferroelectics in addition to Frequency Control. 49(6) June 2002. If we model the tail as a cantilever: Estimation of Piezoelectric Response Estimated voltage: 0.7322 V Voltage Measured in Air Field: 0.207 V Voltage required to bias Ge-doped diode: 0.2 V Sources of Error in Estimation Cantilever does not account as long as oscillation Wave as long as m of eel is not a cantilever; looks more like a sinusoid.

Rectifier Design ACin Reference: as long as mer.com/i-notes.html Proposed Integrated Design Fan Rectifier Storage Circuit Electronics Housing Future Research Dynamic Mechanical Testing (DMA) – Oscilloscope Quantified wave as long as ms (peak amplitude) Frequency Continued Air Stream Testing Possible water system (time permitting) Environmental Protection stiffens the eel Underst in addition to ing vortex shedding

Project Timeline

## Pramuk, Bill Freelance Columnist

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## Variation of Fundamental Constants V.V. Flambaum School of Physics, UNSW, Sydney

Nemerson, Andrea, Freelance Columnist has reference to this Academic Journal, PHwiki organized this Journal Variation of Fundamental Constants V.V. Flambaum School of Physics, UNSW, Sydney, Australia Co-authors: Atomic calculations V.Dzuba, M.Kozlov, E.Angstmann, J.Berengut,M.Marchenko,Cheng Chin,S.Karshenboim,A.Nevsky, S.Porsev Nuclear in addition to QCD calculations E.Shuryak, V.Dmitriev, D.Leinweber, A.Thomas, R.Young, A.Hoell, P.Jaikumar, C.Roberts,S.Wright, A.Tedesco, W.Wiringa Cosmology J.Barrow Quasar data J.Webb,M.Murphy,M.Drinkwater,W.Walsh,P.Tsanavaris, C.Churchill,J.Prochazka,A.Wolfe,S.Muller,C,Henkel, F.Combes, T.Wiklind, thanks to W.Sargent,R.Simcoe Laboratory measurements S.J. Ferrel,,A,Cingoz,ALappiere,A.-T.Nguyen,N.Leefer, D.Budker,S.K.Lamoreuax,J.R.Torgerson,S.Blatt,A.D.Ludlow,G.K.Cambell, J.W.Thomsen,T.Zelevinsky,M.M.Boid,J.Ye,X.Baillard,M.Fouche,R.LeTargat,A.Brush,P.Lemonde,M.Takamoto,F.-L.Hong,H.Katori Motivation Extra space dimensions (Kaluza-Klein, Superstring in addition to M-theories). Extra space dimensions is a common feature of theories unifying gravity with other interactions. Any change in size of these dimensions would manifest itself in the 3D world as variation of fundamental constants. Scalar fields . Fundamental constants depend on scalar fields which vary in space in addition to time (variable vacuum dielectric constant e0 ). May be related to dark energy in addition to accelerated expansion of the Universe  Fine tuning of fundamental constants is needed as long as humans to exist. Example: low-energy resonance in production of carbon from helium in stars (He+He+He=C). Slightly different coupling constants  no resonance - no life. Variation of coupling constants in space provide natural explanation of the fine tuning: we appeared in area of the Universe where values of fundamental constants are suitable as long as our existence. Search as long as variation of fundamental constants Big Bang Nucleosynthesis Quasar Absorption Spectra 1 Oklo natural nuclear reactor Atomic clocks 1 Enhanced effects in atoms 1, molecules1 in addition to nuclei Dependence on gravity evidence 1 Based on atomic in addition to molecular calculations evidences

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Dimensionless Constants Since variation of dimensional constants cannot be distinguished from variation of units, it only makes sense to consider variation of dimensionless constants. Fine structure constant a=e2/hc=1/137.036 Electron or quark mass/QCD strong interaction scale, me,q/LQCD a strong (r)=const/ln(r LQCD /ch) me,q are proportional to Higgs vacuum (weak scale) Variation of strong interaction Gr in addition to unification (Calmet, Fritzsch; Langecker, Segre, Strasser; Wetterich, Dent) Relation between variations of different coupling constants Gr in addition to unification models Calmet,Fritzch; Langecker, Segre, Strasser; Wetterich,Dent

a 3 -1(m)=a strong -1 (m)=b3ln(m /LQCD ) a -1(m)=5/3 a 1 -1(m) + a 2 -1(m) Dependence on quark mass Dimensionless parameter is mq/LQCD . It is convenient to assume LQCD =const, i.e. measure mq in units of LQCD mp is proportional to (mqLQCD)1/2 Dmp/mp=0.5Dmq/mq Other meson in addition to nucleon masses remains finite as long as mq=0. Dm/m=K Dmq/mq Argonne: K are calculated as long as p,n,r,w,s. Nuclear magnetic moments depends on p-meson mass mp p n p p n p Nucleon magnetic moment Spin-spin interaction between valence in addition to core nucleons

Nucleon magnetic moment Nucleon in addition to meson masses QCD calculations: lattice, chiral perturbation theory,cloudy bag model, Dyson-Schwinger in addition to Faddeev equations, semiempirical. Nuclear calculations: meson exchange theory of strong interaction. Nucleon mass in kinetic energy p2/2M Big Bang nucleosynthesis: dependence on quark mass Flambaum, Shuryak 2002 Flambaum, Shuryak 2003 Dmitriev, Flambaum 2003 Dmitriev, Flambaum, Webb 2004 Coc, Nunes, Olive, Uzan,Vangioni 2007 Dent, Stern, Wetterich 2007 Flambaum, Wiringa 2007 Berengut, Dmitriev, Flambaum 2009

Deuterium bottleneck At temeperature T<0.3 Mev all abundances follow deuteron abundance (no other nuclei produced if there are no deuterons) Reaction g d  n p , exponentially small number of energetic photons, e-( Ed/T) Exponetilal sensitivity to deuteron binding energy Ed , Ed=2 Mev , Freezeout temeperure Tf =30 KeV New BBN result Dent,Stern,Wetterich 2007; Berengut, Dmitriev, Flambaum 2009: dependence of BBN on energies of 2,3H,3,4He,6,7Li ,7,8Be Flambaum,Wiringa 2007 : dependence of binding energies of 2,3H,3,4He,6,7Li, 7,8Be on nucleon in addition to meson masses, Flambaum,Holl,Jaikumar,Roberts,Write, Maris 2006: dependence of nucleon in addition to meson masses on light quark mass mq. Big Bang Nucleosynthesis: Dependence on mq/ LQCD 2H 1+7.7x=1.07(15) x=0.009(19) 4He 1-0.95x=1.005(36) x=-0.005(38) 7Li 1-50x=0.33(11) x=0.013(02) Final result x=DXq/Xq =0.013 (02), Xq=mq/ LQCD Big Bang Nucleosynthesis: Dependence on mq/ LQCD 2H 1+7.7x=1.07(15) x=0.009(19) 4He 1-0.95x=1.005(36) x=-0.005(38) 7Li 1-50x=0.33(11) x=0.013(02) result x=DXq/Xq =0.013 (02), Xq=mq/ LQCD Dominated by 7Li abundance (3 times difference), consistent with 2H,4He Nonlinear effects: x=DXq/Xq =0.016 (05) Alkali Doublet Method (Bahcall,Sargent;Varshalovich, Potekhin, Ivanchik, et al) Fine structure interval DFS = E(p3/2) - E(p1/2) = A(Za)2 If Dz is observed at red shift z in addition to D0 is FS measured on Earth then Ivanchik et al, 1999: Da/a = -3.3(6.5)(8) x 10-5. Murphy et al, 2001: Da/a = -0.5(1.3) x 10-5. Variation of fine structure constant a

Many Multiplet Method (Dzuba,Flambaum, Webb) p3/2 p3/2 s1/2 s1/2 p1/2 p1/2 dw >> dDFS ! Advantages: Order of magnitude gain in sensitivity Statistical: all lines are suitable as long as analysis Observe all unverse (up to z=4.2) Many opportunities to study systematic errors a1 a2 w w Quasar absorption spectra Earth Quasar Gas cloud Light a

Quasar absorption spectra Earth Quasar Gas cloud Light a One needs to know E(a2) as long as each line to do the fitting Use atomic calculations to find w(a). For a close to a0 w = w0 + q(a2/a02-1) q is found by varying a in computer codes: q = dw/dx = [w(0.1)-w(-0.1)]/0.2, x=a2/a02-1 a =e2/hc=0 corresponds to non-relativistic limit (infinite c). Use atomic calculations to find w(a). For a close to a0 w = w0 + q(a2/a02-1) q is found by varying a in computer codes: q = dw/dx = [w(0.1)-w(-0.1)]/0.2, x=a2/a02-1

EDMs of atoms of experimental interest dn = 5 x 10-24 e cm h, d(3He)/ dn = 10-5 Summary Atomic in addition to molecular experiments are used to test unification theories of elementary particles Parity violation Weak charge: test of the st in addition to ard model in addition to search of new physics Nuclear anapole, probe of weak PV nuclear as long as ces Time reversal EDM, test of physics beyond the st in addition to ard model. 1-3 orders improvement may be enough to reject or confirm all popular models of CP violation, e.g. supersymmetric models A new generation of experiments with enhanced effects is underway in atoms, diatomic molecules, in addition to solids Publications: V. A. Dzuba, V. V. Flambaum, J, K. Webb, PRL 82, 888 (1999). V. A. Dzuba, V. V. Flambaum, J, K. Webb, PRA 59, 230 (1999). V. A. Dzuba, V. V. Flambaum, PRA 61, 034502 (2000). V. A. Dzuba, V. V. Flambaum, M. T. Murphy, J, K. Webb, LNP 570, 564 (2001). J. K. Webb et al , PRL 87, 091301 (2001). V. A. Dzuba, V. V. Flambaum, M. T. Murphy, J, K. Webb, PRA 63, 042509 (2001). M. M. Murphy et al, MNRAS, 327, 1208 (2001). V. A. Dzuba et al, PRA, 66, 022501 (2002). V. A. Dzuba, V. V. Flambaum, M. V. Marchenko, PRA 68, 022506 (2003). E. J. Angstmann, V. A. Dzuba, V. V. Flambaum, PRA 70, 014102 (2004). J. C. Berengat et al, PRA 70, 064101 (2004). M. M. Murphy et al, LNP, 648, 131 (2004). V. A. Dzuba, PRA, 71, 032512 (2005). V. A. Dzuba, V. V. Flambaum, PRA, 71, 052509 (2005). V. A. Dzuba, V. V. Flambaum, PRA, 72, 052514 (2005). V. A. Dzuba, PRA, 71, 062501 (2005). S. G. Karshenboim et al, physics/0511180.

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## Sheddinglight on arc cathode spots

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## Finding the root cause of ESD problems Dr. David Pommerenke With contributions f

Johnston, Betty, Freelance Columnist has reference to this Academic Journal, PHwiki organized this Journal Finding the root cause of ESD problems Dr. David Pommerenke With contributions from all members of the EMC laboratory University Missouri Rolla  EMC laboratory pommerenke@ece.umr.edu ESD is combines many tests in one test ESD failure analysis Susceptibility scanning Voltage in traces during ESD testing Content Definitions Hard-error: Any error that leads to a physical failure of the IC. (Excessive leakage current, loss of functionality) Soft-error: Any error that can be cured by resetting the system (logical errors: bit error, false reset)

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Physical parameters that may lead to an ESD failure ESD combines many different tests into one test st in addition to ard. From electrostatics, via breakdown physics to a 1 GHz 20kV/m pulse. It failed, what now Is it a soft or a hard failure At which test point did it fail At which voltage did it fail Was it in contact or air discharge mode How repeatable is the failure It has failed! – What to do now Question: What do you do to debug ESD problems How to fix it Exact circuit underst in addition to ing Pro: The most cost efficient solution. Learn how to design in the future. Contra: Need to underst in addition to software Need to underst in addition to circuits Requires specialized equipment May require special firmware Shielding Pro: No system underst in addition to ing needed. If it works, the fast! Contra: Often more expensive solution Adds material But how to do it

20mm 50mm 200mm @ 8kV, restart @ 10kV restart @ 15kV restart EUT display Local probing around the EUT A first start of finding the root cause may be: Locating sensitivity on the outside might help to correlate to the affected IC or trace, but: Outside location may only be a result of breach in shielding Outside location is too broad to correlate to details inside: Lets go inside! Different coupling mechanisms require different probes Injection can be done: To the enclosure To cables To connectors To boards To board traces To lead-frames traces – dm – cm – mm – cm2 – 5 mil (using microscope) – 1 mil (using microscope) Probes used as long as injection

Different coupling mechanisms require different probes Direct injection between to grounds. In selecting the right injection method one has to try to emulate the same excitation mechanism as occurs during the st in addition to ardized test or at the customer site. Anticipating the right method is often guided by carefully observing the differences of failure signature at different test points. Disturbance sources: TLP in addition to narrow pulse The measurement of the high voltage transmission line pulse generator output pulse, about 500 ps rise (20-80%) Less than 200 ps pulse Narrow pulse generator Automated Susceptibility Scanning system of UMR Brief explanation The system moves injection probes to predefined locations, injects pulses in addition to observes the system response. In most cases, pulses are ESD-like, e.g., having rise times 0.1 -2 ns. Injection is done using different injection probes as long as testing direct coupling, E in addition to H-field coupling. If needed, the voltages at the input of the IC are measured during the ESD event.

Automated Susceptibility Scanning system of UMR Critical is the error feedback: A test code needs to be operating on the EUT. The test code signals to the control PC if a malfunction has occurred. If so, the level of injected noise (by source setting, not by induced voltage) is recorded in addition to the EUT is reset. Test flow diagram Example: Identifying sensitive nets Besides direct coupling to an IC, four sensitive nets are identified Only 4 nets are sensitive, but there sensitivity is 10X as strong as any other net Net 1 Net 2 Net 3 Net 4 Net 1 Net 2 Net 3 Net 4

The same area is scanned using different polarization of the H-field probe. The difference between the left in addition to the right polarization is the polarity of the induced noise voltage. The sensitive traces are identified by circuit diagram. If needed a finer scan is per as long as med. Example: Identifying sensitive nets A critical part of the board in the previous scanned area has been fine-scanned using very small magnetic field probe to identify the correct trace The scan resolution was set to 0.5mm x 0.5mm The small probe couples less energy into the trace, but in a highly localized area Example: Identifying sensitive nets Net 1 Net 2 Net 2 Net 3 After comparing the identified sensitive nets with PCB layout, three nets have been identified to be sensitive to ESD The sensitivity of those nets have been quantified in terms of applied voltage in the HV generator Induced current direction on the each sensitive net has been identified Modification to a sensitive net

TX RX 100ohm 330pF Filter Location Modification to a sensitive net Simple Low Pass Be as long as e After Filter location Modification to a sensitive net Scanned Area Medium Magnetic Probe The top side of the PCB is scanned using the medium size magnetic probe with four different polarization Some sensitive areas on the IC are identified Direct coupling to ICs

Direct coupling to ICs Signal couples directly into the IC IC reacts to narrow pulses much narrower than the intended signals 300ps For such an ICs, no PCB or shielding solution is economical. Scanning can identify such situations in addition to help to verify improvements in the IC design, packaging (e.g., flip-chip) or the control software. In our experience, direct coupling to ICs is growing problem: Fast IC process technology is used more in addition to more in badly shielded products. Coupling to PCBs is reduced by burried layers in addition to traces Dense PCBs have hardly any traces visible (BGA packages) New is better, well . Shown are the voltage settings of a pulse generator at which an upset occurs if A narrow pulse (less than 300 ps width at 50% amplitude) is causing an upset of the IC. Note: the new IC per as long as med worse! Worsening ESD soft-error per as long as mance is a significant risk if new processes are introduced, or if I/O structures are modified. Voltages on traces

Semi rigid coax cable, connected to 20GS/sec 6 GHz b in addition to width scope 470 Ohm GND VIA (close to the Trace) How measure in-circuit while pulsing The trace is loaded by 470 + 50 Ohm. The small loop area ensures little dB/dt coupling in addition to good frequency response of the probing method. Three traces have been isolated by terminating/filtering circuits Double pulse has been eliminated The reset line still reacts to this narrow pulse (the system crashed) It has been shown that the IC of interest is causing the crash, reacting to a very narrow pulse Very Narrow pulse on slow status line (< 150ps) leads to crash Voltages on a status line Clock-N Clock-P Pulse has been applied repeatedly, increasing the voltage until system crashes Wave as long as ms are recorded (20 GHz / 6 Gsample/sec). Differential clock ESD Event on differential clock Very sensitive to noise during the transition ESD Event on differential clock No crash! + - Clock-N Clock-P Differential input has an offset The result is repeatable. Increasing difference should not lead to a system crash. Why Noise increased differential voltage IC ESD System level ESD Consequence St in addition to ard Voltage DUT Operating Application method Tested properties When does it occur Destructive CDM / HBM / MM Typically < 3000 IC, sub system System is not powered Direct to the IC PINs IC protection circuits Manufacturing, h in addition to ling Destructive in addition to Upset IEC 61000-4-2 Typically < 15 000 System System is operating Enclosure, PINs System design Qualification tests, Customer site IC in addition to system level ESD testing The board has been scanned with four different probe polarization (up, down, left, right) to take account of the induced current on the board The medium size magnetic field probe was used with 1.5mm x 1.5mm scan resolution ESD sensitive net can be identified roughly, but the resolution is not so fine enough to pin point a single trace. Example: Identifying sensitive nets

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## Development of a Halbach Array Magnetic Levitation System Outline Outline Cont. Introduction Previous Work

Johnston, Betty, Freelance Columnist has reference to this Academic Journal, PHwiki organized this Journal Development of a Halbach Array Magnetic Levitation System By: Dirk DeDecker Jesse VanIseghem Advised by: Mr. Steven Gutschlag Dr. Winfred Anakwa Outline Introduction Previous Work Project Summary Changes to Original Proposal Physics of Halbach Array Magnets Preliminary Calculations in addition to Simulations Outline Cont. Equipment List Lab work Problems in addition to Solutions Results Future Projects Patents References Acknowledgements

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Introduction Magnetic levitation technology can be used in high speed train applications Maglev suspension allows trains to accelerate to over 300 mph in addition to reduces maintenance by almost eliminating all moving parts Previous Work Dr. Sam Gurol in addition to Dr. Richard Post have worked on The General Atomics Low Speed Urban Maglev Technology Development Program utilizing the rotary track method Previous Work Cont. Work by Paul Friend in 2004 Levitation Equations Matlab GUI Work by Glenn Zomchek in 2007 Design of system using Inductrack method Successful levitation to .45 mm.

Previous Work – Results Inductrack results from Glenn Zomcheks project (2007) Project Summary The goals of our project are: Develop an improved Halbach array magnetic levitation system to achieve 0.5 cm at a track speed of 10 m/s Demonstrate successful levitation Changes to Original Proposal Focused on demonstration of levitation of the magnet device Changed closed loop system to open loop

Physics of Halbach Array Magnets Designed by Klaus Halbach Creates a strong, enhanced magnetic field on one side, while almost cancelling the field on the opposite side Peak strength of the array: B0=Br(1-e-kd)sin(/M)/( /M) Tesla k = 2/, M = of magnets, Br = magnet strength, d = thickness of each magnet = Halbach array wavelength Physics of the Inductrack Halbach array moving at velocity v m/sec over inductrack generates flux 0sin(t), 0 Tesla-m2, linking the circuit = (2/)v rad/sec Voltage induced in inductrack circuit: V(t) = 0cos(t) Inductrack R-L circuit current equation: V(t) = Ldi(t)/dt + Ri(t) Physics of the Inductrack Cont Close-packed conductors, made utilizing thin aluminum or copper sheets Allows as long as levitation at low speeds Can be modeled as an RL circuit Transfer function has pole at -R/L

Physics of the Inductrack Cont. Dr. Post used the induced current in addition to magnetic field to derive Lift as long as ce: = Bo2w2/2kL1/1+(R/L)2e-ky1 Drag as long as ce: = Bo2w2/2kL (R/L) /1+(R/L)2e-ky1 Where y1 is the levitation height in meters Physics of the Inductrack Cont. Phase shift relates to drag in addition to levitation as long as ces Lift/Drag = L/R L = 0 w/(2kdc) , where dc is the center to center spacing of conducting strips in addition to w is the track width Physics of the Maglev System Force needed to levitate: F = m9.81 Newtons m=.465 kg F = 4.56 N Breakpoint velocity: By solving Lift/Drag as long as v, vb=/(2) m/sec

Simulation with Matlab GUI Equipment List 9 radius polyethylene wheel, with a width of 2 57x2x1/4 copper sheet of thin conducting strips 125 – 6mm cube neodymium magnets Balsa wood structure to house the 5×25 Halbach array Metal in addition to hardware as long as motor st in addition to Dayton permanent magnet DC motor Digital Force Gauge Model: 475040 Displacement Transducer Model: MLT002N3000B5C Lab Work – Design Designed wheel in addition to copper track to be built Wheel in addition to track were machined by Tri-City Machining

Lab Work – Design Cont. Decided to switch from aluminum track to copper Lower resistivity of copper(Cu = 1.68×10-8 m, Al = 2.82×10-8 m) R = PcRc/(NtcNs) , where Rc is the resistivity Lift/Drag  2v/(L/R) Aluminum Lift/Drag ratio = 0.102 Copper Lift/Drag ratio = 0.171 Lab Work  Halbach Array Device Balsa wood structure built Magnets glued into balsa wood Used shrink wrap in addition to epoxy Aluminum covering built to ensure magnets do not eject from balsa wood Lab Work  Halbach Array Device Array is 5×25 magnets = 28 mm Makes our arc length approximately 8, with an angle of 25 degrees to either side cos(25) = .9063 Arc length s = 90.436 = 3.93 This arc length keeps 90% of the as long as ce in the vertical direction Fv = Ficos() Fi Force Diagram

Lab Work  Set up Motor st in addition to designed in addition to built to hold motor, wheel, in addition to balsa wood device Holes drilled in copper track in addition to track connected to wheel All pieces assembled into the complete system Lab Work  Set up Lab Work  Displacement Sensor Displacement sensor outputs linear voltage change as long as changes in displacement

Problems in addition to Solutions Copper track too short Once holes drilled in copper, track became weak Magnets were very difficult to glue in direction they had to be Results  Force Measurements Results  Displacement Measurements

Results Successful levitation of 0.365 cm at 843 RPM, corresponding to a tangential velocity of 10.0 m/s Materials as long as shield are ordered in addition to will be built Future Projects Closed-loop control of levitation height Dynamically balance wheel More dampening of vibration Acknowledgements Dr. Winfred Anakwa Mr. Steven Gutschlag Mr. Joe Richey in addition to Tri-City Machining Mr. Darren DeDecker in addition to Caterpillar Inc. Mrs. Sue DeDecker Mr. Dave Miller

Results  Backup Table 1: Displacement Sensor Calibration Measurements Table 2: Force Sensor Measurement Results  Backup Table 3: Displacement Sensor Measurements Results  Backup

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## Magnetic fields & electromagnetic induction Learning outcomes Teaching challenges Permanent magnets Defining magnetic flux density

Hymer, Dian, Freelance Columnist has reference to this Academic Journal, PHwiki organized this Journal Magnetic fields & electromagnetic induction Learning outcomes describe magnetic fields in terms of magnetic flux & flux density use Flemings left in addition to right h in addition to rules to describe interactions between magnetic field & current quantitatively describe B fields around a straight current-carrying wire in addition to a solenoid quantitatively describe the as long as ce on a charged particle moving at right angles to a uni as long as m B field explain electromagnetic induction using Faradays & Lenzs law use the concept of flux linkage to explain how trans as long as mers work describe how B fields are used in circular particle accelerators recall the postulates in addition to key consequences of special relativity solve related quantitative problems Teaching challenges fields are abstract involves 3-D thinking but generally illustrated in 2-D involves rates of change different concepts have similar names some physical quantities have a variety of equivalent units students may need simple trigonometry to find the magnetic flux, or magnetic as long as ce, correctly identifying angle .

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Permanent magnets Magnetic field lines start in addition to finish at poles. Physicists picture this as a flow in magnetic circuit. magnetic flux (phi), unit Weber magnetic flux density B, unit Weber m-2 or Tesla Carl Gauss & Wilhelm Weber investigated geomagnetism in 1830s, made accurate measurements of magnetic declination in addition to inclination, built the first electromagnetic telegraph. Defining magnetic flux density Typical magnetic field strengths: Flemings left-h in addition to rule: Force on the wire is perpendicular to both l in addition to B. Electromagnetism Electric currents have loops of B flux around them. Current-turns produce flux.

Magnetic fields near currents long straight wire long solenoid, N turns in addition to length l is the permeability of free space Forces on parallel currents parallel – attract anti-parallel – repel Forces on parallel currents At the top wire in the diagram, Defining the ampere (straight wires of infinite length) If the current in each wire is exactly 1 A, in addition to the distance between the wires is 1 m, then the as long as ce on each metre length of the wires will be 2 x 10-7 N. Practice questions: TAP Forces on currents

Demonstration: fine beam tube uni as long as m B-field at right angles to an electron beam with v F is perpendicular to v, so the beam travels in a circular path. Force on a moving charge Fluxes in addition to as long as ces Michael Faraday (experimenting in 1830s at the Royal Institution) pictured magnetic field lines as flexible in addition to elastic magnetic attraction: field lines try to get shorter & straighter magnetic repulsion: field lines cannot cross Faradays law of induction Induced emf is proportional to rate of cutting field lines. N is number of turns on the secondary coil. N is its flux linkage. Induced emf is proportional to rate of change in coils flux linkage. NOTE: Eddy currents are induced in iron core linking primary in addition to secondary coils. These can be reduced by laminations in core.

1 the flux cut by a moving wire 2 the change in flux due to a magnet moving 3 the change in flux due to a stationary electromagnet which is changing in strength No relative motion means no induced emf. Under what conditions is there an induced current can be: Experiments Force on a current-carrying wire Current balance Investigating fields near currents (using a Hall probe) Investigating electromagnetic induction Faradays law Jumping ring Practice questions (Adv Physics) Changes in flux linkage (Adv Physics) Flux or flux linkage TAP Rates of change (Adv Physics) Graphs of changing flux in addition to emf

Endpoints rotating coil (AC) generator: motors produce a back emf

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