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Lindsey, C.

Publications and source records attributed to Lindsey, C..

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Hanford Site Raptor Nest Monitoring Report for Calendar Year 2022

The U.S. Department of Energy, Richland Operations Office (DOE-RL), conducts ecological monitoring on the Hanford Site to collect and track data needed to ensure compliance with an array of environmental laws, regulations, and policies governing DOE-RL activities. Ecological monitoring data provide baseline information about the plants, animals, and habitats under DOERL stewardship at the Hanford Site required for decision making under the National Environmental Policy Act of 1969 (NEPA) and Comprehensive Environmental Response, Compensation, and Liability Act of 1980. DOE/EIS-0222, Final Hanford Comprehensive Land Use Plan Environmental Impact Statement, (CLUP) evaluates the potential environmental impacts associated with implementing a comprehensive land-use plan for the Hanford Site for at least the next 50 years and ensures that DOE-RL, its contractors, and other entities conduct activities on the Hanford Site in compliance with NEPA.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Hanford Site Bird Surveys Report for Calendar Year 2016

Resource stewardship is an integral part of the U.S. Department of Energy, Richland Operations Office (DOE-RL) responsibilities at the Hanford Site. Efficient conservation or management of any species or any population is supported through the availability of reliable information on the population in question. DOERL conducts ecological monitoring on the Hanford Site to collect and track this information. Ecological monitoring data provide baseline information about the plants, animals, and habitat under DOE-RL stewardship at Hanford that is required for decision-making under the National Environmental Policy Act (NEPA) and Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The Hanford Site Comprehensive Land Use Plan (CLUP, DOE/EIS-0222-F), which is the Environmental Impact Statement for Hanford Site activities, helps ensure that DOE-RL, its contractors, and other entities conducting activities on the Hanford Site are in compliance with NEPA.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Hanford Site Roadside Bird Surveys Report for Calendar Year 2018

The U.S. Department of Energy, Richland Operations Office (DOE-RL) conducts ecological monitoring on the Hanford Site to collect and track data needed to ensure compliance with an array of environmental laws, regulations, and policies governing DOE-RL activities. Ecological monitoring data provide baseline information about the plants, animals, and habitats under DOE-RL stewardship at Hanford which is required for decision-making under the National Environmental Policy Act (NEPA) and Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The Hanford Site Comprehensive Land Use Plan (CLUP, DOE/EIS- 0222-F), which is the Environmental Impact Statement for Hanford Site activities, helps ensure that DOE-RL, its contractors, and other entities conducting activities on the Hanford Site are in compliance with NEPA.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Characterisation of the dip-bump structure observed in proton–proton elastic scattering at $\sqrt{s}$ = 8 TeV

The TOTEM collaboration at the CERN LHC has measured the differential cross-section of elastic proton–proton scattering at √s = 8TeV in the squared four-momentum transfer range 0.2GeV 2 < |t| < 1.9GeV 2 . This interval includes the structure with a diffractive minimum (“dip”) and a secondary maximum (“bump”) that has also been observed at all other LHC energies, where measurements were made. A detailed characterisation of this structure for √s = 8 TeV yields the positions, |t| dip = (0.521 ± 0.007)GeV 2 and |t| bump = (0.695 ± 0.026)GeV 2 , as well as the cross-section values, dσ/dt| dip = (15.1 ± 2.5)μb/GeV 2 and dσ/dt| bump = (29.7 ± 1.8)μb/GeV 2 , for the dip and the bump, respectively.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

Elastic differential cross-section ${\mathrm{d}}\sigma /{\mathrm{d}}t$ at $\sqrt{s}=2.76\hbox {TeV}$ and implications on the existence of a colourless C-odd three-gluon compound state

The proton-proton elastic differential cross section dσ/dt has been measured by the TOTEM experiment at √ s = 2.76 TeV energy with β* = 11 m beam optics. The Roman Pots were inserted to 13 times the transverse beam size from the beam, which allowed to measure the differential cross-section of elastic scattering in a range of the squared four-momentum transfer (|t|) from 0.36 GeV 2 to 0.74 GeV 2 . The differential cross-section can be described with an exponential in the |t|-range between 0.36 and 0.54 GeV 2 , followed by a diffractive minimum (dip) at |t dip | = (0.61 ± 0.03) GeV 2 and a subsequent maximum (bump). The ratio of the dσ/dt at the bump and at the dip is 1.7±0.2. When compared to the proton–antiproton measurement of the D0 experiment at √ s = 1.96 TeV, a significant difference can be observed. Under the condition that the effects due to the energy difference between TOTEM and D0 can be neglected, the result provides evidence for a colourless C-odd three-gluon bound state exchange in the t-channel of the proton-proton and proton–antiproton elastic scattering.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Elastic differential cross-section measurement at $\sqrt{s}=13$ TeV by TOTEM

The TOTEM collaboration has measured the elastic proton-proton differential cross section dσ/d t at √s = 13 TeV LHC energy using dedicated β* = 90 m beam optics. The Roman Pot detectors were inserted to 10σ distance from the LHC beam, which allowed the measurement of the range [0.04 GeV 2 ; 4 GeV 2 ] in four-momentum transfer squared | t |. The efficient data acquisition allowed to collect about 10 9 elastic events to precisely measure the differential cross-section including the diffractive minimum (dip), the subsequent maximum (bump) and the large-| t | tail. The average nuclear slope has been found to be B = (20.40 ± 0.002 stat ± 0.01syst) GeV –2 in the | t |-range 0.04–0.2 GeV 2 . The dip position is | t dip | = (0.47 ± 0.004 stat ± 0.01 syst ) GeV 2 . The differential cross section ratio at the bump vs. at the dip R = 1.77 ± 0.01 stat has been measured with high precision. The series of TOTEM elastic pp measurements show that the dip is a permanent feature of the pp differential cross-section at the TeV scale.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

First measurement of elastic, inelastic and total cross-section at $$\sqrt{s}=13$$ s = 13 TeV by TOTEM and overview of cross-section data at LHC energies: TOTEM Collaboration

The TOTEM collaboration has measured the proton–proton total cross section at s√=13 TeV with a luminosity-independent method. Using dedicated β*=90 m beam optics, the Roman Pots were inserted very close to the beam. The inelastic scattering rate has been measured by the T1 and T2 telescopes during the same LHC fill. After applying the optical theorem the total proton–proton cross section is σ tot =(110.6 ± 3.4 ) mb, well in agreement with the extrapolation from lower energies. This method also allows one to derive the luminosity-independent elastic and inelastic cross sections σ el =(31.0 ± 1.7) mb and σ inel =(79.5 ± 1.8) mb .

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS1995

Submillimeter solar research with the KAO

From 1981 to 1988 the KAO was used to measure the 30 to 670 micron continuum radiation from the Sun. The most significant result was te measurement of the limb brightness and extent during two total solar eclipses. The results clearly indicate a solar limb at 50 to 670 microns which is extended beyond that expected for an atmosphere in hydrostatic equilibrium. Unique measurements of far infrared solar oscillations and brightness of active regions were also carried out. A complete set of references is included.

Becklin, Eric E.↗
NASA NTRS1992

Chromospheric dynamics based on infrared solar brightness variations

The NASA Kuiper Airborne Observatory was used to observe far-infrared continuum brightness fluctuations in the lower chromosphere due to solar 5 minute oscillations on the quiet sun. Brightness measurements made at 50, 100, 200, and 400 microns show a strong correlation with visible-line Doppler measurements from photospheric and chromospheric altitudes. The motion of the chromosphere is nearly in phase over a large range of heights, while the infrared brightness lags the Doppler velocity by phases varying from significantly less than 90 deg at low altitudes to nearly 90 deg at higher altitudes. It is proposed that this is the result of a nonadiabatic response of the chromospheric gas to compression and may indicate an important mechanism for wave dissipation. Thermal relaxation times ranging from about 40 s at 340 km above the tau(5000) = 1 photosphere to about 300 s at 600 km are proposed.

Kopp, G.↗
NASA NTRS1990

Far-infrared intensity variations caused by 5 minute oscillations

Observations of solar IR intensity variations at 50, 100, and 200 microns were made simultaneously and cospatially with Doppler measurements in the sodium D1 line at 5896 A. Brightness temperature variations of several K in amplitude are highly correlated with five minute Doppler oscillations. The brightness variations are attributed to work done on the chromospheric medium by compression, driven by the five minute oscillations. The Doppler oscillations lead the brightness variations by about 47 deg in phase at 50 and 100 microns and by about 72 deg in phase at 200 microns.

Lindsey, C.↗
NASA NTRS1990

Statistical concepts in radiative transfer through inhomogeneous media

The theory of radiative transfer in inhomogeneous media is extended to handle transfer for scale lengths small compared to the scale size of the inhomogeneity. This is called the microscopic domain of inhomogeneous radiative transfer. A concept called the vector intensity distribution is introduced to characterize the statistical properties of radiation in various species of medium. Radiative transfer in an inhomogeneous atmosphere is expressed in terms of the evolution of this vector intensity distribution and its various moments along the optical path.

Lindsey, C.↗
NASA NTRS1987

LTE modeling of inhomogeneous chromospheric structure using high-resolution limb observations

The paper discusses considerations relevant to LTE modeling of rough atmospheres. Particular attention is given to the application of recent high-resolution observations of the solar limb in the far-infrared and radio continuum to the modeling of chromospheric spicules. It is explained how the continuum limb observations can be combined with morphological knowledge of spicule structure to model the physical conditions in chromospheric spicules. This discussion forms the basis for a chromospheric model presented in a parallel publication based on observations ranging from 100 microns to 2.6 mm.

Lindsey, C.↗
NASA NTRS1987

A solar chromosphere and spicule model based on far-infrared limb observations

Techniques developed for LTE radiative transfer problems in a rough atmosphere were used to compute a model chromosphere containing spicules consistent with high-resolution solar limb observations from 100 microns to 2.6 mm. The model consists of a smooth, plane-parallel temperature minimum region extending from the photosphere to a height of 1000 km and randomly distributed cylindrical spicules above this height. It is found that the observed limb brightness profiles are well fitted by spicules with electron temperatures on the order of 7000 K.

Braun, D.↗
NASA NTRS1987

Submillimeter diagnostics of the response of the solar chromosphere to compressional waves

The NASA Infrared Telescope Facility has been used to observe local continuum brightness variations of the quiet sun in 350 and 800 micron radiation simultaneously. Variations of order 5 K are found at both wavelengths, with a strong correlation between the two. The 800 micron variations lag behind the 350 micron variations by 25-35 deg in phase. This is similar to unexpected phase shifts reported by Lites and Chipman in 1979 and Lites, Chipman, and White in 1982 between velocity and intensity for certain chromospheric lines. It is proposed that the phase lags observed are the result of nonadiabatic response of the chromosphere to compression, which could be an important mechanism for dissipation of mechanical energy.

Lindsey, C.↗
NASA NTRS1986

Solar chromospheric modeling based on submillimeter limb brightness profile

A method of modeling the solar chromosphere is developed, based on submillimeter continuum observations of the solar limb. Submillimeter radiation from the solar limb emanates from the chromosphere in local thermodynamic equilibrium, making it an important chromospheric diagnostic. Also, the use of high-resolution limb profiles allows for atmospheric modeling independent of gravitational hydrostatic equilibrium. The chromospheric model is constructed to match high-resolution solar limb profiles at 30, 50, 100, and 200 microns, determined by an occultation of the solar limb observed from the Kuiper Airborne Observatory during the total solar eclipse of July 31, 1981. This matching is achieved by 'stretching' the solar model atmosphere of Vernazza, Avrett, and Loesser (1981) vertically out of hydrostatic equilibrium, while maintainingn its vertical temperature-optical depth profile.

Hermans, L. M.↗
NASA NTRS1986

Extreme limb profiles of the sun at far-infrared and submillimeter wavelengths

Thirty, 50, 100, and 200 microns solar limb intensity profiles determined with arcsecond resolution from airborne observations of the occultation of the solar limb during the total eclipse of July 31, 1981, are presented. Two points of particular importance emerge: (1) the longer-wavelength (100 and 200 micron) limbs are significantly brighter than disk center. At 200 microns the extreme limb is about 1.22 times the brightness of disk center. This is consistent with the 6000 K temperature-plateau structure of the model chromospheres of Vernazza, Avrett, and Loeser (1973, Ap. J., 184, 605; 1981; Ap. J. Suppl., 45, 635); and (2) the longer wavelength limbs are extended significantly further above the visible limb than Vernazza, Avrett, and Loeser predict. These results provide a strong basis for modeling of the solar chromosphere free from the assumption of gravitational-hydrostatic equilibrium.

Lindsey, C.↗