American Association of Physics Teachers: American Journal of Physics: Table of Contents
Table of Contents for American Journal of Physics. List of articles from both the latest and ahead of print issues.
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American Association of Physics Teachers: American Journal of Physics: Table of Contents
American Association of Physics Teachers
enUS
American Journal of Physics
https://aapt.scitation.org/na101/home/literatum/publisher/aip/journals/content/ajp/2023/ajp.2023.91.issue3/ajp.2023.91.issue3/2023021701/ajp.2023.91.issue3.cover.jpg
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In this issue: March 2023
https://aapt.scitation.org/doi/10.1119/5.0142817?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 165166, March 2023. <br/>
American Journal of Physics, Volume 91, Issue 3, Page 165166, March 2023. <br/>
In this issue: March 2023
10.1119/5.0142817
American Journal of Physics
20230217T04:15:32Z
© 2023 Author(s).
John Essick
Harvey Gould
Adam Fritsch
Claire A. MarracheKikuchi
Beth Parks
B. Cameron Reed
Donald Salisbury
Jan Tobochnik

2022 AAPT award citations at the winter meeting in Portland, Oregon
https://aapt.scitation.org/doi/10.1119/5.0143043?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 167169, March 2023. <br/>
American Journal of Physics, Volume 91, Issue 3, Page 167169, March 2023. <br/>
2022 AAPT award citations at the winter meeting in Portland, Oregon
10.1119/5.0143043
American Journal of Physics
20230217T04:15:20Z
© 2023 Author(s).

Is contour integration essential? Alternatives for beginning physics students
https://aapt.scitation.org/doi/10.1119/5.0084475?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 170176, March 2023. <br/>The standard method to evaluate many definite integrals that are encountered in physics is contour integration. Here, we show how these can be evaluated by other means, enlarging the toolbox available to students and enabling the discussion of physical problems where these integrals arise before contour integration is introduced.
American Journal of Physics, Volume 91, Issue 3, Page 170176, March 2023. <br/>The standard method to evaluate many definite integrals that are encountered in physics is contour integration. Here, we show how these can be evaluated by other means, enlarging the toolbox available to students and enabling the discussion of physical problems where these integrals arise before contour integration is introduced.
Is contour integration essential? Alternatives for beginning physics students
10.1119/5.0084475
American Journal of Physics
20230217T04:15:23Z
© 2023 Author(s).
Onuttom Narayan

A shorter path to some action variables
https://aapt.scitation.org/doi/10.1119/5.0118683?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 177181, March 2023. <br/>This paper shows how to apply Leibniz's integral rule to calculate the action variables for the Kepler problem. This method offers an attractive alternative to the usual technique of complex contour integration. The method presented here to calculate definite integrals has a broad scope and is especially suitable for undergraduates who are unfamiliar with complex analysis.
American Journal of Physics, Volume 91, Issue 3, Page 177181, March 2023. <br/>This paper shows how to apply Leibniz's integral rule to calculate the action variables for the Kepler problem. This method offers an attractive alternative to the usual technique of complex contour integration. The method presented here to calculate definite integrals has a broad scope and is especially suitable for undergraduates who are unfamiliar with complex analysis.
A shorter path to some action variables
10.1119/5.0118683
American Journal of Physics
20230217T04:15:21Z
© 2023 Author(s).
Juan F. Zanella Béguelin

An exploration of circumbinary systems using gravitational microlensing
https://aapt.scitation.org/doi/10.1119/5.0088604?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 182192, March 2023. <br/>Gravitational microlensing is one of the methods to detect exoplanets–planets outside our solar system. Here, we focus on the theoretical modeling of systems with three lensing objects and in particular circumbinary systems. Circumbinary systems include two stars and at least one planet and are estimated to represent a sizeable portion of all exoplanets. Extending a method developed for binary lenses to the three lens case, we explore the parameter space of circumbinary systems, producing exact magnification maps and light curves.
American Journal of Physics, Volume 91, Issue 3, Page 182192, March 2023. <br/>Gravitational microlensing is one of the methods to detect exoplanets–planets outside our solar system. Here, we focus on the theoretical modeling of systems with three lensing objects and in particular circumbinary systems. Circumbinary systems include two stars and at least one planet and are estimated to represent a sizeable portion of all exoplanets. Extending a method developed for binary lenses to the three lens case, we explore the parameter space of circumbinary systems, producing exact magnification maps and light curves.
An exploration of circumbinary systems using gravitational microlensing
10.1119/5.0088604
American Journal of Physics
20230217T04:15:32Z
© 2023 Author(s).
Brett C. George
EleniAlexandra Kontou
Patrycja Przewoznik
Eleanor Turrell

Producing slow light in warm alkali vapor using electromagnetically induced transparency
https://aapt.scitation.org/doi/10.1119/5.0128967?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 193205, March 2023. <br/>We present undergraduatefriendly instructions on how to produce light pulses propagating through warm Rubidium vapor with speeds less than 400 m/s, i.e., nearly a million times slower than c. We elucidate the role played by electromagnetically induced transparency (EIT) in producing slow light pulses and discuss how to achieve the required experimental conditions. The optical setup is presented, and details provided for preparation of pump, probe, and reference pulses of the required size, frequency, intensity, temporal width, and polarization purity. EITbased slow light pulses provide the most widely studied architecture for creating quantum memories. Therefore, the basic concepts presented here are useful for physics and engineering majors who wish to get involved in the development of cuttingedge quantum technologies.
American Journal of Physics, Volume 91, Issue 3, Page 193205, March 2023. <br/>We present undergraduatefriendly instructions on how to produce light pulses propagating through warm Rubidium vapor with speeds less than 400 m/s, i.e., nearly a million times slower than c. We elucidate the role played by electromagnetically induced transparency (EIT) in producing slow light pulses and discuss how to achieve the required experimental conditions. The optical setup is presented, and details provided for preparation of pump, probe, and reference pulses of the required size, frequency, intensity, temporal width, and polarization purity. EITbased slow light pulses provide the most widely studied architecture for creating quantum memories. Therefore, the basic concepts presented here are useful for physics and engineering majors who wish to get involved in the development of cuttingedge quantum technologies.
Producing slow light in warm alkali vapor using electromagnetically induced transparency
10.1119/5.0128967
American Journal of Physics
20230217T04:15:34Z
© 2023 Author(s).
Kenneth DeRose
Kefeng Jiang
Jianqiao Li
Macbeth Julius
Linzhao Zhuo
Scott Wenner
Samir Bali

A tabletop experiment for speed of light measurement using a Red Pitaya STEMlab board
https://aapt.scitation.org/doi/10.1119/5.0099720?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 206213, March 2023. <br/>The speed of light is an important fundamental constant in physics, and so determining its value is a common undergraduate laboratory experiment. Methods to measure the light speed can help students practice their experimental skills and become familiar with the concepts of modern precision measurement techniques. In this paper, we demonstrate that a tabletop optical setup, comprised of an affordable Red Pitaya STEMlab board and a lowcost laser diode module, can be used to accurately determine the speed of light by measuring the frequency response of the phase shift between intensitymodulated light beams reflected by two end mirrors separated by 50 cm. By using the STEMlab builtin Bode analyzer to automatically scan the modulation frequency over the range from 10 to 40 MHz, the frequency response of phase is measured and recorded. These phase shift data are then used to calculate the speed of light with an uncertainty of less than 0.5%. With the help of the Red Pitaya board, the number of required electronic instruments for our setup is reduced. All of the required components are commercially available, and no electronic construction work is necessary so that teachers and students can implement the experiment in a plugandplay manner.
American Journal of Physics, Volume 91, Issue 3, Page 206213, March 2023. <br/>The speed of light is an important fundamental constant in physics, and so determining its value is a common undergraduate laboratory experiment. Methods to measure the light speed can help students practice their experimental skills and become familiar with the concepts of modern precision measurement techniques. In this paper, we demonstrate that a tabletop optical setup, comprised of an affordable Red Pitaya STEMlab board and a lowcost laser diode module, can be used to accurately determine the speed of light by measuring the frequency response of the phase shift between intensitymodulated light beams reflected by two end mirrors separated by 50 cm. By using the STEMlab builtin Bode analyzer to automatically scan the modulation frequency over the range from 10 to 40 MHz, the frequency response of phase is measured and recorded. These phase shift data are then used to calculate the speed of light with an uncertainty of less than 0.5%. With the help of the Red Pitaya board, the number of required electronic instruments for our setup is reduced. All of the required components are commercially available, and no electronic construction work is necessary so that teachers and students can implement the experiment in a plugandplay manner.
A tabletop experiment for speed of light measurement using a Red Pitaya STEMlab board
10.1119/5.0099720
American Journal of Physics
20230217T04:15:30Z
© 2023 Author(s).
CheChung Chou
ShiYu Hsaio
JunZhi Feng
Tyson Lin
ShengHua Lu

Singular Lagrangians and the Dirac–Bergmann algorithm in classical mechanics
https://aapt.scitation.org/doi/10.1119/5.0107540?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 214224, March 2023. <br/>Textbook treatments of classical mechanics typically assume that the Lagrangian is nonsingular; that is, the matrix of second derivatives of the Lagrangian with respect to the velocities is invertible. This assumption ensures that (i) Lagrange's equations can be solved for the accelerations as functions of coordinates and velocities, and (ii) the definitions of the conjugate momenta can be inverted to solve for the velocities as functions of coordinates and momenta. This assumption, however, is unnecessarily restrictive—there are interesting classical dynamical systems with singular Lagrangians. The algorithm for analyzing such systems was developed by Dirac and Bergmann in the 1950s. After a brief review of the Dirac–Bergmann algorithm, several examples are presented using familiar components: point masses connected by massless springs, rods, cords, and pulleys.
American Journal of Physics, Volume 91, Issue 3, Page 214224, March 2023. <br/>Textbook treatments of classical mechanics typically assume that the Lagrangian is nonsingular; that is, the matrix of second derivatives of the Lagrangian with respect to the velocities is invertible. This assumption ensures that (i) Lagrange's equations can be solved for the accelerations as functions of coordinates and velocities, and (ii) the definitions of the conjugate momenta can be inverted to solve for the velocities as functions of coordinates and momenta. This assumption, however, is unnecessarily restrictive—there are interesting classical dynamical systems with singular Lagrangians. The algorithm for analyzing such systems was developed by Dirac and Bergmann in the 1950s. After a brief review of the Dirac–Bergmann algorithm, several examples are presented using familiar components: point masses connected by massless springs, rods, cords, and pulleys.
Singular Lagrangians and the Dirac–Bergmann algorithm in classical mechanics
10.1119/5.0107540
American Journal of Physics
20230217T04:15:33Z
© 2023 Author(s).
J. David Brown

Particleincell method for plasmas in the onedimensional electrostatic limit
https://aapt.scitation.org/doi/10.1119/5.0135515?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 225234, March 2023. <br/>We discuss the particleincell (PIC) method, which is one of the most widely used approaches for the kinetic description of plasmas. The positions and velocities of the charged particles take continuous values in phase space, and spatial macroscopic quantities, such as the charge density and selfgenerated electric fields, are calculated at discrete spatial points of a grid. We discuss the computer implementation of the PIC method for onedimensional plasmas in the electrostatic regime and discuss a desktop application (PlasmAPP), which includes the implementation of different numerical and interpolation methods and diagnostics in a graphical user interface. To illustrate its functionality, the electronelectron twostream instability is discussed. Readers can use PlasmAPP to explore advanced numerical methods and simulate different phenomena of interest.
American Journal of Physics, Volume 91, Issue 3, Page 225234, March 2023. <br/>We discuss the particleincell (PIC) method, which is one of the most widely used approaches for the kinetic description of plasmas. The positions and velocities of the charged particles take continuous values in phase space, and spatial macroscopic quantities, such as the charge density and selfgenerated electric fields, are calculated at discrete spatial points of a grid. We discuss the computer implementation of the PIC method for onedimensional plasmas in the electrostatic regime and discuss a desktop application (PlasmAPP), which includes the implementation of different numerical and interpolation methods and diagnostics in a graphical user interface. To illustrate its functionality, the electronelectron twostream instability is discussed. Readers can use PlasmAPP to explore advanced numerical methods and simulate different phenomena of interest.
Particleincell method for plasmas in the onedimensional electrostatic limit
10.1119/5.0135515
American Journal of Physics
20230217T04:15:21Z
© 2023 Author(s).
Sara Gomez
Jaime Humberto Hoyos
Juan Alejandro Valdivia

Continuous fractional component Gibbs ensemble Monte Carlo
https://aapt.scitation.org/doi/10.1119/5.0135841?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 235246, March 2023. <br/>A continuous fractional component (CFC) approach increases the probability of particle swaps in the context of vaporliquid equilibrium simulations using the Gibbs ensemble Monte Carlo algorithm. Two variants of the CFC approach are compared for simulations of pure LennardJones (LJ) fluids and binary LJ mixtures as examples. The details of an exemplary CFC implementation are presented. Recommendations are provided to reduce the effort required for the suggested problems.
American Journal of Physics, Volume 91, Issue 3, Page 235246, March 2023. <br/>A continuous fractional component (CFC) approach increases the probability of particle swaps in the context of vaporliquid equilibrium simulations using the Gibbs ensemble Monte Carlo algorithm. Two variants of the CFC approach are compared for simulations of pure LennardJones (LJ) fluids and binary LJ mixtures as examples. The details of an exemplary CFC implementation are presented. Recommendations are provided to reduce the effort required for the suggested problems.
Continuous fractional component Gibbs ensemble Monte Carlo
10.1119/5.0135841
American Journal of Physics
20230217T04:15:31Z
© 2023 Author(s).
Niklas Mayr
Michael Haring
Thomas Wallek

From Sackur–Tetrode entropy to the ideal gas adiabatic equation in one step
https://aapt.scitation.org/doi/10.1119/5.0139175?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 247248, March 2023. <br/>We present an alternative derivation of the relation between temperature and volume for a reversible, adiabatic process involving an ideal gas. The derivation for a monatomic gas starts with the Sackur–Tetrode equation and takes only one step. We also address the extension to diatomic gases.
American Journal of Physics, Volume 91, Issue 3, Page 247248, March 2023. <br/>We present an alternative derivation of the relation between temperature and volume for a reversible, adiabatic process involving an ideal gas. The derivation for a monatomic gas starts with the Sackur–Tetrode equation and takes only one step. We also address the extension to diatomic gases.
From Sackur–Tetrode entropy to the ideal gas adiabatic equation in one step
10.1119/5.0139175
American Journal of Physics
20230217T04:15:34Z
© 2023 Author(s).
P.M. Binder
Ian R. Leigh

Erratum: “Introducing simple models of social systems” [Am. J. Phys. 90, 462468 (2022)]
https://aapt.scitation.org/doi/10.1119/5.0134837?af=R&feed=mostrecent
American Journal of Physics, <a href="https://aapt.scitation.org/toc/ajp/91/3">Volume 91, Issue 3</a>, Page 248248, March 2023. <br/>
American Journal of Physics, Volume 91, Issue 3, Page 248248, March 2023. <br/>
Erratum: “Introducing simple models of social systems” [Am. J. Phys. 90, 462468 (2022)]
10.1119/5.0134837
American Journal of Physics
20230217T04:15:23Z
© 2023 Author(s).
Pablo Jensen