J. Douglas Patterson
- Courses10
- Reviews21
- School: Johnson County Community College
- Campus:
- Department: Astronomy
- Email address: Join to see
- Phone: Join to see
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Location:
12345 College Blvd
Overland Park, KS - 66210 - Dates at Johnson County Community College: January 2003 - July 2019
- Office Hours: Join to see
Biography
Johnson County Community College - Astronomy
Professor of Astronomy at Johnson County Community College
Higher Education
J. Douglas
Patterson
Kansas City, Missouri Area
Doug teaches physics and astronomy at Johnson County Community College in Overland Park, KS, and researches solar energetic particles at Fundamental Technologies in Lawrence, KS. When not teaching or crunching numbers, he's either at a track photographing and covering motor racing for Formula1Blog.com, or competing in SCCA autocross, rallycross, or TSD road rallies for Dare2Dream Motorsports. He also helps his wife run their small photography business Patterson Prints, LLP.
Experience
Johnson County Community College
Professor of Astronomy
I teach the introductory astronomy course, ASTR 122, the honors astronomy sections, ASTR 291, and the Math and Physics for Games course, PHYS 191.
Fundamental Technologies, LLC
Researcher
I conduct research on solar energetic particles and the interplanetary medium as well as providing support for our various free-to-the-public data products and archives.
TheParcFerme.com
Associate Editor / Photographer
I cover grassroots and junior formula motorsports, including the Road 2 Indy ladder program, offering event coverage and photography as well as opinion, analysis, and prognostication. As a member of the Sports Car Club of America, I also write about my own experiences competing in Solo, RallyCross, and TSD Road Rally events.
OpenPaddock.net
Chief Photographer and Associate Editor
I was invited to join OpenPaddock.net in March of 2009 as a contributing writer and photographer. As the site has grown, I now serve as Chief Photographer as well as the Associate Editor and defacto Public Relations Coordinator. I also frequently appear as co-host on our weekly podcast, and am responsible for our Mazda Road to Indy content.
Patterson Prints, LLP
Photographer
I assist my wife as co-owner of Patterson Prints where we offer landscape and landmark photography of Lafayette County, Missouri. We also provide product and property photography services.
Education
Ball State University
MS
Physics
Performed standard and differential photometry on three different suspected cataclysmic variables at a variety of wavelengths and determined the temperatures of the various components of the star systems. Data for this work were collected at the Ball State University Observatory and at Lowell Observatory in Flagstaff, AZ.The University of Kansas
PhD
Physics
Investigated the energies and abundances of various energetic particles in both the low and high latitude heliosphere using the HISCALE instrument on the Ulysses spacecraft, the EPAM instrument on the ACE spacecraft, and the CPME instrument on the IMP-8 spacecraft.University of Central Missouri
BS
Physics
Publications
Statistical study of low-energy heliosphere particle fluxes from 1.4 to 5 AU over a solar cycle
Space Weather
Throughout the entire Ulysses mission, the Heliosphere Instrument for Spectra, Composition, and Anisotropy at Low Energies (HI-SCALE) has collected measurements of low-energy interplanetary ions and electrons. Time series of electron, proton, and ion fluxes have been obtained since 1990. We present statistical studies of high-resolution ion and electron energy spectra (~50 keV to ~5 MeV) as measured by the HI-SCALE instrument on the Ulysses spacecraft over a time interval longer than a solar cycle (1990 to 2004). Ulysses is the only spacecraft that continually measured the inner (~1.4 to ~5 AU) heliosphere particle population during these years. The data thus provide measures of the lower-energy population of particles that a spacecraft traveling outward from Earth would have encountered and that also could have impacted the atmosphere and surface of Mars and of its satellites during this interval. Comparisons of Ulysses particle fluxes with those from the Electron, Proton, and Alpha Monitor (EPAM) instrument on the Advanced Composition Explorer (ACE) spacecraft (the HI-SCALE backup instrument) have shown that azimuthal and heliolatitude dependencies of particle fluxes in the inner heliosphere following solar events are not as extreme as might be expected. Thus the Ulysses measurements, while taken over a range of heliolatitudes, can provide important statistical information that can be used to estimate the low-energy radiation dosages and potential sputtering fluxes to planetary surfaces and to heliosphere spacecraft surfaces and solar arrays over a solar cycle.
Statistical study of low-energy heliosphere particle fluxes from 1.4 to 5 AU over a solar cycle
Space Weather
Throughout the entire Ulysses mission, the Heliosphere Instrument for Spectra, Composition, and Anisotropy at Low Energies (HI-SCALE) has collected measurements of low-energy interplanetary ions and electrons. Time series of electron, proton, and ion fluxes have been obtained since 1990. We present statistical studies of high-resolution ion and electron energy spectra (~50 keV to ~5 MeV) as measured by the HI-SCALE instrument on the Ulysses spacecraft over a time interval longer than a solar cycle (1990 to 2004). Ulysses is the only spacecraft that continually measured the inner (~1.4 to ~5 AU) heliosphere particle population during these years. The data thus provide measures of the lower-energy population of particles that a spacecraft traveling outward from Earth would have encountered and that also could have impacted the atmosphere and surface of Mars and of its satellites during this interval. Comparisons of Ulysses particle fluxes with those from the Electron, Proton, and Alpha Monitor (EPAM) instrument on the Advanced Composition Explorer (ACE) spacecraft (the HI-SCALE backup instrument) have shown that azimuthal and heliolatitude dependencies of particle fluxes in the inner heliosphere following solar events are not as extreme as might be expected. Thus the Ulysses measurements, while taken over a range of heliolatitudes, can provide important statistical information that can be used to estimate the low-energy radiation dosages and potential sputtering fluxes to planetary surfaces and to heliosphere spacecraft surfaces and solar arrays over a solar cycle.
Steady-state event-excluded proton spectra at solar minimum at all heliolatitudes
Geophysical Research Letters
We present spectra of a steady foreground population of particles in the inner heliosphere observed by the Heliosphere Instrument for Spectra, Composition, and Anisotopy at Low Energies (HISCALE) on board the Ulysses spacecraft. The observed spectra come from the full range of heliolatitudes visited by Ulysses, -80 to +80 degrees, during Ulysses' first full orbit of the Sun during solar minimum. New corrections for background were applied resulting in a more sensitive and higher energy resolution data set that we used here to analyze quiet-time (event-excluded) spectra. We found a persistent foreground population of energetic protons that permeate the inner heliosphere. These protons have complex energy spectra suggesting multiple acceleration sources, and these particles move predominently in non-radial directions. These findings support the idea that the inner heliosphere acts as a reservoir for energetic protons.
Statistical study of low-energy heliosphere particle fluxes from 1.4 to 5 AU over a solar cycle
Space Weather
Throughout the entire Ulysses mission, the Heliosphere Instrument for Spectra, Composition, and Anisotropy at Low Energies (HI-SCALE) has collected measurements of low-energy interplanetary ions and electrons. Time series of electron, proton, and ion fluxes have been obtained since 1990. We present statistical studies of high-resolution ion and electron energy spectra (~50 keV to ~5 MeV) as measured by the HI-SCALE instrument on the Ulysses spacecraft over a time interval longer than a solar cycle (1990 to 2004). Ulysses is the only spacecraft that continually measured the inner (~1.4 to ~5 AU) heliosphere particle population during these years. The data thus provide measures of the lower-energy population of particles that a spacecraft traveling outward from Earth would have encountered and that also could have impacted the atmosphere and surface of Mars and of its satellites during this interval. Comparisons of Ulysses particle fluxes with those from the Electron, Proton, and Alpha Monitor (EPAM) instrument on the Advanced Composition Explorer (ACE) spacecraft (the HI-SCALE backup instrument) have shown that azimuthal and heliolatitude dependencies of particle fluxes in the inner heliosphere following solar events are not as extreme as might be expected. Thus the Ulysses measurements, while taken over a range of heliolatitudes, can provide important statistical information that can be used to estimate the low-energy radiation dosages and potential sputtering fluxes to planetary surfaces and to heliosphere spacecraft surfaces and solar arrays over a solar cycle.
Steady-state event-excluded proton spectra at solar minimum at all heliolatitudes
Geophysical Research Letters
We present spectra of a steady foreground population of particles in the inner heliosphere observed by the Heliosphere Instrument for Spectra, Composition, and Anisotopy at Low Energies (HISCALE) on board the Ulysses spacecraft. The observed spectra come from the full range of heliolatitudes visited by Ulysses, -80 to +80 degrees, during Ulysses' first full orbit of the Sun during solar minimum. New corrections for background were applied resulting in a more sensitive and higher energy resolution data set that we used here to analyze quiet-time (event-excluded) spectra. We found a persistent foreground population of energetic protons that permeate the inner heliosphere. These protons have complex energy spectra suggesting multiple acceleration sources, and these particles move predominently in non-radial directions. These findings support the idea that the inner heliosphere acts as a reservoir for energetic protons.
Correlation of solar energetic protons and polar cap absorption
Journal of Geophysical Research
This study shows the results of a model of polar cap absorption events (PCAs) using solar energetic proton flux as an input. The proton data are recorded by the Charged Particle Measurement Experiment (CPME) on board the IMP 8 satellite and are collected by the Applied Physics Laboratory at Johns Hopkins University. The IMP 8 satellite orbits the Earth at distances between 30 and 35 Earth radii, which places it in the solar energetic particle environment throughout most of its orbit. It has been shown in previous studies that these solar energetic particles have direct and immediate access to the polar atmosphere [Reid, 1970]. Our model shows that the majority of the ionization resulting from the influx of solar energetic protons occurs in the altitude range from ∼ 50–90 km. Excess ionization at these altitudes causes enhanced absorption of cosmic HF radio waves. The levels of absorption used for comparison in this study were measured directly by the riometer at South Pole station, Antarctica. The results show a very strong correlation between the incident proton flux and measured path-integrated cosmic HF radio noise absorption for significant events, involving absorptions greater than 1.0 dB. For absorption levels lower than this it is obvious that other phenomena dominate. For HF radio waves the primary contributors to PCA are protons with energies near 20 MeV. This study extends the correlated observations of interplanetary particles and PCA throughout a 9-year period. The close quantitative agreement between the measured and calculated values of absorption supports the validity of the assumptions and suppositions made by this model. The data also suggest a method by which the path-integrated cosmic noise absorption may be used to probe the E and D layers of the ionosphere to determine the effective ion-electron recombination coefficients within these regions.
Statistical study of low-energy heliosphere particle fluxes from 1.4 to 5 AU over a solar cycle
Space Weather
Throughout the entire Ulysses mission, the Heliosphere Instrument for Spectra, Composition, and Anisotropy at Low Energies (HI-SCALE) has collected measurements of low-energy interplanetary ions and electrons. Time series of electron, proton, and ion fluxes have been obtained since 1990. We present statistical studies of high-resolution ion and electron energy spectra (~50 keV to ~5 MeV) as measured by the HI-SCALE instrument on the Ulysses spacecraft over a time interval longer than a solar cycle (1990 to 2004). Ulysses is the only spacecraft that continually measured the inner (~1.4 to ~5 AU) heliosphere particle population during these years. The data thus provide measures of the lower-energy population of particles that a spacecraft traveling outward from Earth would have encountered and that also could have impacted the atmosphere and surface of Mars and of its satellites during this interval. Comparisons of Ulysses particle fluxes with those from the Electron, Proton, and Alpha Monitor (EPAM) instrument on the Advanced Composition Explorer (ACE) spacecraft (the HI-SCALE backup instrument) have shown that azimuthal and heliolatitude dependencies of particle fluxes in the inner heliosphere following solar events are not as extreme as might be expected. Thus the Ulysses measurements, while taken over a range of heliolatitudes, can provide important statistical information that can be used to estimate the low-energy radiation dosages and potential sputtering fluxes to planetary surfaces and to heliosphere spacecraft surfaces and solar arrays over a solar cycle.
Steady-state event-excluded proton spectra at solar minimum at all heliolatitudes
Geophysical Research Letters
We present spectra of a steady foreground population of particles in the inner heliosphere observed by the Heliosphere Instrument for Spectra, Composition, and Anisotopy at Low Energies (HISCALE) on board the Ulysses spacecraft. The observed spectra come from the full range of heliolatitudes visited by Ulysses, -80 to +80 degrees, during Ulysses' first full orbit of the Sun during solar minimum. New corrections for background were applied resulting in a more sensitive and higher energy resolution data set that we used here to analyze quiet-time (event-excluded) spectra. We found a persistent foreground population of energetic protons that permeate the inner heliosphere. These protons have complex energy spectra suggesting multiple acceleration sources, and these particles move predominently in non-radial directions. These findings support the idea that the inner heliosphere acts as a reservoir for energetic protons.
Correlation of solar energetic protons and polar cap absorption
Journal of Geophysical Research
This study shows the results of a model of polar cap absorption events (PCAs) using solar energetic proton flux as an input. The proton data are recorded by the Charged Particle Measurement Experiment (CPME) on board the IMP 8 satellite and are collected by the Applied Physics Laboratory at Johns Hopkins University. The IMP 8 satellite orbits the Earth at distances between 30 and 35 Earth radii, which places it in the solar energetic particle environment throughout most of its orbit. It has been shown in previous studies that these solar energetic particles have direct and immediate access to the polar atmosphere [Reid, 1970]. Our model shows that the majority of the ionization resulting from the influx of solar energetic protons occurs in the altitude range from ∼ 50–90 km. Excess ionization at these altitudes causes enhanced absorption of cosmic HF radio waves. The levels of absorption used for comparison in this study were measured directly by the riometer at South Pole station, Antarctica. The results show a very strong correlation between the incident proton flux and measured path-integrated cosmic HF radio noise absorption for significant events, involving absorptions greater than 1.0 dB. For absorption levels lower than this it is obvious that other phenomena dominate. For HF radio waves the primary contributors to PCA are protons with energies near 20 MeV. This study extends the correlated observations of interplanetary particles and PCA throughout a 9-year period. The close quantitative agreement between the measured and calculated values of absorption supports the validity of the assumptions and suppositions made by this model. The data also suggest a method by which the path-integrated cosmic noise absorption may be used to probe the E and D layers of the ionosphere to determine the effective ion-electron recombination coefficients within these regions.
The low energy magnetic spectrometer on Ulysses and ACE response to near relativistic protons
Astronomy & Astrophysics
Aims: We show that the Heliosphere Instrument for Spectra Composition and Anisotropy at Low Energies (HISCALE) on board the Ulysses spacecraft and the Electron Proton Alpha Monitor (EPAM) on board the Advance Composition Explorer (ACE) spacecraft can be used to measure properties for ion populations with kinetic energies in excess of 1 GeV. This previously unexplored source of information is valuable for understanding the origin of near relativistic ions of solar origin. Methods: We model the instrumental response from the low energy magnetic spectrometers from EPAM and HISCALE using a Monte Carlo approach implemented in the Geant4 toolkit to determine the response of different energy channels to energies up to 5 GeV. We compare model results with EPAM observations for 2012 May 17 ground level solar cosmic ray event, including directional fluxes. Results: For the 2012 May event, all the ion channels in EPAM show an onset more than one hour before ions with the highest nominal energy range (1.8 to 4.8 MeV) were expected to arrive. We show from Monte Carlo simulations that the timing at different channels, the ratio between counts at the different channels, and the directional fluxes within a given channel, are consistent with and can be explained by the arrival of particles with energies from 35 MeV to more than 1 GeV. Onset times for the EPAM penetrating protons are consistent with the rise seen in neutron monitor data, implying that EPAM and ground neutron monitors are seeing overlapping energy ranges and that both are consistent with GeV ions being released from the Sun at 10:38 UT.
Statistical study of low-energy heliosphere particle fluxes from 1.4 to 5 AU over a solar cycle
Space Weather
Throughout the entire Ulysses mission, the Heliosphere Instrument for Spectra, Composition, and Anisotropy at Low Energies (HI-SCALE) has collected measurements of low-energy interplanetary ions and electrons. Time series of electron, proton, and ion fluxes have been obtained since 1990. We present statistical studies of high-resolution ion and electron energy spectra (~50 keV to ~5 MeV) as measured by the HI-SCALE instrument on the Ulysses spacecraft over a time interval longer than a solar cycle (1990 to 2004). Ulysses is the only spacecraft that continually measured the inner (~1.4 to ~5 AU) heliosphere particle population during these years. The data thus provide measures of the lower-energy population of particles that a spacecraft traveling outward from Earth would have encountered and that also could have impacted the atmosphere and surface of Mars and of its satellites during this interval. Comparisons of Ulysses particle fluxes with those from the Electron, Proton, and Alpha Monitor (EPAM) instrument on the Advanced Composition Explorer (ACE) spacecraft (the HI-SCALE backup instrument) have shown that azimuthal and heliolatitude dependencies of particle fluxes in the inner heliosphere following solar events are not as extreme as might be expected. Thus the Ulysses measurements, while taken over a range of heliolatitudes, can provide important statistical information that can be used to estimate the low-energy radiation dosages and potential sputtering fluxes to planetary surfaces and to heliosphere spacecraft surfaces and solar arrays over a solar cycle.
Steady-state event-excluded proton spectra at solar minimum at all heliolatitudes
Geophysical Research Letters
We present spectra of a steady foreground population of particles in the inner heliosphere observed by the Heliosphere Instrument for Spectra, Composition, and Anisotopy at Low Energies (HISCALE) on board the Ulysses spacecraft. The observed spectra come from the full range of heliolatitudes visited by Ulysses, -80 to +80 degrees, during Ulysses' first full orbit of the Sun during solar minimum. New corrections for background were applied resulting in a more sensitive and higher energy resolution data set that we used here to analyze quiet-time (event-excluded) spectra. We found a persistent foreground population of energetic protons that permeate the inner heliosphere. These protons have complex energy spectra suggesting multiple acceleration sources, and these particles move predominently in non-radial directions. These findings support the idea that the inner heliosphere acts as a reservoir for energetic protons.
Correlation of solar energetic protons and polar cap absorption
Journal of Geophysical Research
This study shows the results of a model of polar cap absorption events (PCAs) using solar energetic proton flux as an input. The proton data are recorded by the Charged Particle Measurement Experiment (CPME) on board the IMP 8 satellite and are collected by the Applied Physics Laboratory at Johns Hopkins University. The IMP 8 satellite orbits the Earth at distances between 30 and 35 Earth radii, which places it in the solar energetic particle environment throughout most of its orbit. It has been shown in previous studies that these solar energetic particles have direct and immediate access to the polar atmosphere [Reid, 1970]. Our model shows that the majority of the ionization resulting from the influx of solar energetic protons occurs in the altitude range from ∼ 50–90 km. Excess ionization at these altitudes causes enhanced absorption of cosmic HF radio waves. The levels of absorption used for comparison in this study were measured directly by the riometer at South Pole station, Antarctica. The results show a very strong correlation between the incident proton flux and measured path-integrated cosmic HF radio noise absorption for significant events, involving absorptions greater than 1.0 dB. For absorption levels lower than this it is obvious that other phenomena dominate. For HF radio waves the primary contributors to PCA are protons with energies near 20 MeV. This study extends the correlated observations of interplanetary particles and PCA throughout a 9-year period. The close quantitative agreement between the measured and calculated values of absorption supports the validity of the assumptions and suppositions made by this model. The data also suggest a method by which the path-integrated cosmic noise absorption may be used to probe the E and D layers of the ionosphere to determine the effective ion-electron recombination coefficients within these regions.
The low energy magnetic spectrometer on Ulysses and ACE response to near relativistic protons
Astronomy & Astrophysics
Aims: We show that the Heliosphere Instrument for Spectra Composition and Anisotropy at Low Energies (HISCALE) on board the Ulysses spacecraft and the Electron Proton Alpha Monitor (EPAM) on board the Advance Composition Explorer (ACE) spacecraft can be used to measure properties for ion populations with kinetic energies in excess of 1 GeV. This previously unexplored source of information is valuable for understanding the origin of near relativistic ions of solar origin. Methods: We model the instrumental response from the low energy magnetic spectrometers from EPAM and HISCALE using a Monte Carlo approach implemented in the Geant4 toolkit to determine the response of different energy channels to energies up to 5 GeV. We compare model results with EPAM observations for 2012 May 17 ground level solar cosmic ray event, including directional fluxes. Results: For the 2012 May event, all the ion channels in EPAM show an onset more than one hour before ions with the highest nominal energy range (1.8 to 4.8 MeV) were expected to arrive. We show from Monte Carlo simulations that the timing at different channels, the ratio between counts at the different channels, and the directional fluxes within a given channel, are consistent with and can be explained by the arrival of particles with energies from 35 MeV to more than 1 GeV. Onset times for the EPAM penetrating protons are consistent with the rise seen in neutron monitor data, implying that EPAM and ground neutron monitors are seeing overlapping energy ranges and that both are consistent with GeV ions being released from the Sun at 10:38 UT.
An analysis of solar energetic particles throughout the inner heliosphere
University of Kansas (PhD Dissertation)
This is the result of a survey of the energetic particle spectra in the inner regions of the Solar System, from 1 to 5 AU, both within and above the ecliptic plane using the high energy resolution particle detectors on the Heliosphere Instrument for Spectral, Composition, and Anisotropy at Low Energies (HISCALE) on board the Ulysses spacecraft and the Electron Proton Alpha Monitor (EPAM) on board the Advanced Composition Explorer (ACE). The goals of the study are to determine the interplanetary mechanisms by which energetic ions and electrons are accelerated, to gain more insight into the nature of various recurrent events, and to quantify the latitude dependence of the spectra of the energetic ions and electrons. We first present the results of the analysis of the background rates for EPAM and HISCALE. During the first fast latitude scan of the Ulysses orbit, there was a systematic attenuation of the HISCALE MFSA background rates within the streamer belts (20 60 degrees heliographic latitude). It is suspected that these attenuations are the result of the modulation of relativistic ions of galactic origin and relativistic electrons of galactic and perhaps Jovian origin. The first full Ulysses orbit, after the recognition of the significantly different backgrounds at different latitudes, was divided into five basic regions: north and south polar regions, the streamer belts, 1.5 AU equatorial, and 5.2 AU equatorial regions. The energy spectra for 60 4000 keV ions and 40 400 keV electrons are very different in these five regions and the model of interplanetary acceleration of ions by CIRs beyond 2 3 AU is upheld by our observations.
