Author name code: bray
ADS astronomy entries on 2022-09-14
=author:"Bray, R.J."
------------------------------------------------------------------------
Title: The Solar Granulation
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.
Bibcode: 2009sogr.book.....B
Altcode:
Preface; Acknowledgements; 1. Historical introduction; 2. The
morphology, evolution and dynamics of the granulation and
supergranulation; 3. An introduction to the theory of convection;
4. The theory of astrophysical convection; Interpretation of the
granulation and spuergranulation; References; Name index; Subject index.
Title: Plasma Loops in the Solar Corona
Authors: Bray, R. J.; Cram, L. E.; Durrant, C.; Loughhead, R. E.
Bibcode: 2006plsc.book.....B
Altcode:
1. Historical introduction; 2. Cool loops: observed properties; 3. Hot
loops: observed properties; 4. Flare loops: observed properties;
5. Structure, dynamics and heating of loops; 6. The plasma loop model
of the coronae of the sun and stars.
Title: Book-Review - Plasma Loops in the Solar Corona
Authors: Bray, R. J.; Cram, L. E.; Durrant, C. J.; Loughhead, R. E.;
Kleczek, J.
Bibcode: 1992SoPh..138..423B
Altcode:
No abstract at ADS
Title: Book-Review - Plasma Loops in the Solar Corona
Authors: Bray, R. J.; Cram, L. E.; Currant, C. J.; Loughhead, R. E.
Bibcode: 1991JBAA..101R.300B
Altcode:
No abstract at ADS
Title: Plasma Loops in the Solar Corona
Authors: Bray, R. J.; Cram, L. E.; Durrant, C.; Loughhead, R. E.
Bibcode: 1991plsc.book.....B
Altcode: 1991QB529.P57......
A comprehensive account of the properties of plasma loops, the
fundamental structural elements of the solar corona. Plasma loops
cover a wide range of sizes and range in temperature from tens of
thousands to millions of degrees. They not only define the structure of
individual active regions but connect different active regions--even
across the solar equator. Loops also play an integral and decisive
role in the enormous solar explosions called flares. Over recent
years a wealth of space and ground-based observations of loops has
been obtained in various widely-spaced regions of the electromagnetic
spectrum. In this book the authors have selected the best observational
material from the literature on which to base a detailed account of
the properties of flare and non-flare loops. The book also explores
the larger implications of the loop structures for our understanding
of solar and stellar coronae. The text is enhanced by a large number
of illustrations and unique and beautiful photographs obtained from
the ground and from space.
Title: Plasma loops in the solar corona.
Authors: Bray, R. J.; Cram, L. E.; Durrant, C. J.; Loughhead, R. E.
Bibcode: 1991CAS....18.....B
Altcode:
This book presents the first comprehensive account of the properties
of plasma loops, the fundamental structural elements of the solar
corona. Plasma loops not only define the structure of individual
active regions but connect different active regions. Loops also play an
integral and decisive role in solar flares. The authors have selected
the best observational material from the literature on which to base a
detailed account of the properties of flare and non-flare loops. The
book also explores the larger implications of the loop structures in
our understanding of solar and stellar coronae. The text is enhanced
by a large number of illustrations and photographs obtained from the
ground and from space.
Title: A heat-absorbing prime focus diaphragm for LEST.
Authors: Bray, R. J.; Macrae, R. E.
Bibcode: 1990LFTR...43.....B
Altcode:
The general principles and details of the design and construction
of the proposed heat-absorbing diaphragm for LEST are outlined. The
results of a theoretical analysis of the expected performance of the
new device, including an estimate of the coolant temperature rise
are presented. The authors conclude with a brief discussion of the
integration of the device with the LEST structure and systems and with
recommendations for future work.
Title: A computer-controlled triple-Fabry-Perot universal filter
for solar research.
Authors: Bray, R. J.
Bibcode: 1988LFTR...35.....B
Altcode:
The purpose of this report is to briefly describe the main features of
a triple-Fabry-Perot filter developed at the CSIRO Division of Applied
Physics and currently installed on the 30-cm refractor of the CSIRO
Solar Observatory, Culgoora.
Title: High-Resolution Photography of the Solar
Chromosphere. XXIII. Direct Measurement of the Optical Thickness of
H alpha Solar Loops
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1986ApJ...301..989B
Altcode:
A method has been devised which, under appropriate observational
circumstances, enables a direct determination to be made of the optical
thickness t(L) of high-rising H-alpha solar loops observed on the
disk. It is applicable to both bright and dark loops and requires no
knowledge of the source function in the loop; it is best adapted to
optically thin ones. The technique has been successfully applied to
four loops observed under various circumstances, giving values of t(L)
ranging from 0.06 to 1.3. It is not restricted to H-alpha loops but,
in principle, could also be applied to chromospheric and coronal fine
structures observed in the visible, EUV, and X-ray regions.
Title: High-resolution photography of the solar chromosphere. XXI
Determination of the physical conditions in an H-alpha active-region
loop
Authors: Loughhead, R. E.; Bray, R. J.; Wang, J. -L.
Bibcode: 1985ApJ...294..697L
Altcode:
Values of the electron temperature, electron density, gas density,
gas pressure, degree of hydrogen ionization, and other physical
conditions are determined at seven locations along the axis of an
H-alpha active-region loop observed on the solar disk. Combining these
data with earlier results, a fairly complete description is presented
of the true geometry, flow velocities, and thermodynamic conditions
in such a loop at one moment of time. The physical conditions show
a marked variation along the loop. The variations in density and
pressure exhibit a wavelike nature, with an apparent wavelength of
some 50,000-60,000 km. The results offer the prospect of putting
observational constraints on theoretical models of coronal loops and
of identifying the types of flows and waves present.
Title: Book-Review - the Solar Granulation
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.; Weiss, N. O.
Bibcode: 1985SoPh...96..423B
Altcode:
No abstract at ADS
Title: Book-Review - the Solar Granulation - ED.2
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.; Waddington,
W. G.
Bibcode: 1985Obs...105...18B
Altcode:
No abstract at ADS
Title: High-resolution photography of the solar chromosphere. XX
True widths of H-alpha active region loops
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1985A&A...142..199B
Altcode:
The true widths are measured of two very thin (sub-arcsec) loops
observed on the disk at Hα+1.0 Å at a height of several thousand
kilometers. A realistic deconvolution procedure is applied to correct
for the combined instrumental profile of telescope and atmosphere. This
yields upper and lower limits to the true widths, corresponding to
the possible range in the magnitude of the effective aperture of the
telescope (Fried parameter) at the moment of observation.
Title: Book-Review - the Solar Granulation
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1984Sci...226..571B
Altcode:
No abstract at ADS
Title: Book-Review - the Solar Granulation
Authors: Bray, R. J.; Loughhead, R. E.; Durant, C. J.
Bibcode: 1984AExpr...1Q..39B
Altcode:
No abstract at ADS
Title: High-resolution photography of the solar chromosphere. XIX -
Flow velocities along an active region loop
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1984ApJ...283..392L
Altcode:
True flow velocities along the central axis of an active region
loop have been determined for the first time. This has been done
by combining measurement of the line-of-sight velocity at a number
of points with a mathematical technique for reconstructing the true
shape, size, and orientation of a (tilted) loop observed on the solar
disk. The loop material is found to rise from the surface along one
leg with an increasing upward velocity despite the retarding effect of
gravity. Descending material in the other leg suffers a retarding force
and does not attain the velocity of free fall. The derived velocities
are supersonic at all points measured; the Mach number exceeds 5 at
one location.
Title: Book-Review - the Solar Granulation
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.; Kleczek, J.
Bibcode: 1984Ap&SS.103..410B
Altcode:
No abstract at ADS
Title: Book-Review - the Solar Granulation - ED.2
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.
Bibcode: 1984JBAA...94R.196B
Altcode:
No abstract at ADS
Title: Book-Review - the Solar Granulation - ED.2
Authors: Bray, R. J.
Bibcode: 1984Natur.309R.477B
Altcode:
No abstract at ADS
Title: Isophotes of a large granule
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1984A&A...133..409B
Altcode:
Isophotal contour maps of a single large photospheric granule
are presented, derived from three high-quality photographs taken
within a short time interval. The brightness distribution is markedly
asymmetrical, both the brightest and darkest points being located away
from the geometrical centre. The maps show real structural features on
a scale down to ≡0arcsec.5, but smaller distortions in the isophotes
are artifacts due to residual seeing effects.
Title: Book-Review - the Solar Granulation
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.; Nordlund, A.
Bibcode: 1984SSRv...39R.222B
Altcode:
No abstract at ADS
Title: Book-Review - the Solar Granulation
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.
Bibcode: 1984S&T....68T.426B
Altcode:
No abstract at ADS
Title: The solar granulation Durrant.
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.
Bibcode: 1984cup..book.....B
Altcode:
A comprehensive account of observational and theoretical knowledge
of solar granulation is presented. A historical introduction to
the solar granulation is given, and the morphology, evolution,
and dynamics of granulation and supergranulation are discussed. The
theory of convection is introduced, and the theory of astrophysical
convection is addressed. Finally, the interpretation of granulation
and supergranulation is considered.
Title: Book-Review - the Solar Granulation
Authors: Bray, R. J.; Loughhead, R. E.; Durrant, C. J.
Bibcode: 1984AExpr...1S..39B
Altcode:
No abstract at ADS
Title: High-resolution photography of the solar chromosphere. XVI. Hα
contrast profiles of active region loops.
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1983SoPh...85..131B
Altcode:
High-resolution filtergrams of an active region loop taken at seven
wavelengths in Hα have been used to derive the contrast at eleven
locations along its length as a function of wavelength. With an
appropriate choice of parameters, theoretical curves calculated
on the basis of the `cloud" model give a reasonable fit to the
observed contrast profiles. The inferred line-of-sight components of
the mass velocity range from 27 km s−1 upward to 78 km
s−1 downward. However, more accurate profiles and a more
rigorous theory are needed to confirm the validity of this application
of the cloud model.
Title: The Wavelength Variation of the Granule / Intergranule Contrast
Authors: Bray, R. J.
Bibcode: 1982SoPh...77..299B
Altcode:
Modern measurements of the granule contrast are reviewed and compared
with a curve showing the wavelength variation to be expected on the
assumption of black-body emission as well as with the predictions of
recent inhomogeneous models. The difference in effective temperature
between granules and intergranular lanes is ≈ 270-280 K.
Title: A Refined Measurement of the Sunspot Radiative Flux Deficit
Authors: Bray, R. J.
Bibcode: 1981SoPh...69....3B
Altcode:
New measurements of the radiative flux deficits of two large sunspots
are presented, based on detailed isophotometric maps. Results are
given separately for umbrae and penumbrae. The umbral and penumbral
deficits are 4-5 × 1010 and 1-1.5 × 1010 erg
cm−2 s−1 respectively, the larger figures
ref to the larger spot. Over limited areas centered on the umbral
`cores' the deficits for the two spots amount to 76 and 86% of the
photospheric flux.
Title: Australia and the Transit of Venus
Authors: Bray, R. J.
Bibcode: 1980PASA....4..114B
Altcode: 1980PASAu...4..114B
No abstract at ADS
Title: Bright Dots Inside Sunspots
Authors: Thiessen, G.; Loughhead, R. E.; Bray, R. J.; Tappere, E. J.
Bibcode: 1980S&T....59..120T
Altcode:
No abstract at ADS
Title: Book-Review - Sunspots
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1980S&T....59..241B
Altcode:
No abstract at ADS
Title: A sunspot-auroral Solar Index from 522 B.C. to A.D. 1968.
Authors: Bray, R. J.
Bibcode: 1980NZJS...23...99B
Altcode:
No abstract at ADS
Title: Book-Review - Sunspots
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1980Sci...208..428B
Altcode:
No abstract at ADS
Title: Improved observations of sunspot umbral dots.
Authors: Loughhead, R. E.; Bray, R. J.; Tappere, E. J.
Bibcode: 1979A&A....79..128L
Altcode:
New observations have been obtained of the umbrae of 18 spots
near the solar disk center using the CSIRO 30-cm refractor in its
photospheric mode under seeing-monitor control (Bray and Loughhead,
1977). The telescope was programmed to take sequences of photographs
with exposures ranging (for a large spot) up to 13 times that for
the photosphere in order to capture the fine detail in all parts of
each umbra. Under normal circumstances the level of scattered light
(instrumental plus atmospheric) in the Culgoora Telescope has been
found to be less than 0.9% (Bray and Loughhead, 1977). For the umbral
observations it was further reduced by placing small diaphragms at the
prime focus in the manner described by Bray and Loughhead, 1964). The
umbral dot structure is discussed. The observations made show that
umbral dots virtually cover the umbra, including the darkest regions
of large spots, where the low contrast of the dot pattern has hitherto
hindered its observations.
Title: Sunspots.
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1979suns.book.....B
Altcode:
No abstract at ADS
Title: On the possibility of measuring stellar convection parameters.
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1978PASP...90..609B
Altcode:
The detailed knowledge of solar convection now available is used to
evaluate the possibility of deriving some of the surface convection
parameters of other stars from line-profile measurements. A theory
is outlined for computing integrated line profiles with convection,
rotation, and limb darkening. This theory is employed to calculate
line profiles for rotating convecting stars of the solar class for
values of equatorial v sin i ranging from 0 to 10 km/s. Fourier sine
transforms for solar-class stars are examined, and applications to
stars not of the solar class are discussed. Several possible sources
of line asymmetry are identified.
Title: A convective correction to measured solar wavelengths.
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1978ApJ...224..276B
Altcode:
Convective motions in the solar photosphere associated with the
granulation introduce an asymmetry into a spatially averaged line
profile and shift the wavelength of the center of gravity to the
violet. This shift leads to a significant error in absolute wavelength
determinations based on spatially averaged spectra. The magnitude of
the error depends on a large number of granulation and line profile
parameters and must be computed separately for each line. Calculations
based on modern values of the various parameters lead to a violet shift
at the center of the solar disk of about 0.0035 A for the center of
gravity of the photospheric line of Fe I at 6569.2 A. The correction to
the Oxford measurements of this line reduces the apparent discrepancy
between the observed redshift and the predicted gravitational shift
by one-half. Consideration of both the Oxford and Georgetown results
leads to the conclusion that there is no convincing evidence at the
present time for a real discrepancy.
Title: Fourier transforms applied to the contrast profile method of
measuring vector magnetic fields.
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1978PASP...90..230L
Altcode:
The contrast profile method of measuring strong magnetic fields
(Loughhead and Bray 1976) offers the advantages of high spatial
resolution and freedom from the saturation effects encountered with
the conventional magnetograph. This paper explores theoretically the
extent to which the application of Fourier transforms to magnetic
contrast profile data can facilitate the derivation of the various
field and velocity parameters. For a stationary solar feature, Fourier
transforms offer no advantage. However, for a moving feature the Fourier
sine transform provides a simpler and more sensitive means of inferring
the magnitude and direction of the field and the line-of-sight velocity
than the original contrast data.
Title: Instrumental profile of a triple Fabry-Perot interferometer
for use in solar spectroscopy.
Authors: Loughhead, R. E.; Bray, R. J.; Brown, N.
Bibcode: 1978ApOpt..17..415L
Altcode:
A universal filter for use in solar spectroscopy is under
development, consisting of a computer-controlled triple Fabry-Perot
interferometer. The paper explores the extent to which the performance
of such a filter is degraded by off-axis effects under the intended
conditions of use. Computed instrumental profiles for both on- and
off-axis cases are presented. The calculated bandwidths range from
0.21 A to 0.047 A at eight wavelengths of interest in the visible
region of the spectrum.
Title: A new determination of the granule/ intergranule contrast.
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1977SoPh...54..319B
Altcode:
A new determination of the granule/intergranule contrast is described,
based on high-quality photographs taken with the Culgoora refractor
operating in its photospheric mode. The measurements are corrected
for scattered light and for spatial smearing due to telescope and
atmosphere. The contrast calculated on the basis of the Utrecht
Reference Photosphere lies just outside the range of possible values
permitted by the present observations, 0.76 ⩽ C⩽ 0.81 at λ5500. New
determinations of the mean cell size of the granulation pattern (=
1″.9 of arc) and of the distribution of cell sizes are also presented.
Title: Erratum: "Convective velocities derived from granule contrast
profiles in Fe I lambda 6569.2" [Sol. Phys., Vol. 49, p. 3 - 18
(1976)].
Authors: Bray, R. J.; Loughhead, R. E.; Tappere, E. J.
Bibcode: 1977SoPh...55..274B
Altcode:
No abstract at ADS
Title: Computer-controlled narrow-band optical filters in solar
astronomy
Authors: Bray, R. J.
Bibcode: 1977RaF....20.1318B
Altcode:
Two narrow-band optical filters with specific applications in solar
astronomy are described. The first is a computer-controlled 1/8-A
birefringent filter designed for observations in the H-alpha line
and also in the photospheric Fe I line at 6569 A. The second, still
under construction, has a wavelength-dependent bandwidth of 1/22 to
1/48 A, consists of three computer- and servo-controlled Fabry-Perot
interferometers operating in tandem, and is intended for observations
in the H-alpha line as well as in nine other Fraunhofer lines. As an
example of the use of the computer-controlled filters, it is shown how
photographs taken in the 6569-A line of Fe I with the 1/8-A filter
have been employed to obtain a more accurate determination of the
convection velocity associated with solar granulation.
Title: Visibility of magnetic features on filtergrams and
spectroheliograms.
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1976SoPh...50..297L
Altcode:
An expression is derived for the contrast variation of a hypothetical
magnetic element observed with a tunable monochromatic filter or
spectroheliograph in a triplet Zeeman line. The theory is valid for a
magnetic field of arbitrary strength and direction and for polarizing
and non-polarizing optics. Numerical results are presented for both
a stationary and a moving magnetic element over a range of field
strengths and directions. They provide a simple diagnostic means of
inferring the presence or, alternatively, the absence of strong fields,
such as the kilogauss network fields postulated by Stenflo and others
on the basis of indirect evidence. The proposed method of measuring
strong fields is capable of very high spatial resolution and is free
of the saturation effects encountered in the conventional magnetograph.
Title: Convective velocities derived from granule contrast profiles
in Fe i λ 6569.2
Authors: Bray, R. J.; Loughhead, R. E.; Tappere, E. J.
Bibcode: 1976SoPh...49....3B
Altcode:
A new determination of the granular and intergranular velocities is
described, based on a new approach. The method involves measurement
of the granule/intergranule contrast as a function of wavelength on a
sequence of filtergrams taken with the CSIRO computer-controlled 1/8 Å
filter in the photospheric line Fe I λ6569.2. A procedure based on a
simple but realistic morphological model of the granulation pattern is
used to correct for spatial smearing. The effects of spectral smearing
and of scattered light are also taken into account.
Title: Visibility of the photospheric granulation in Fe i λ 6569.2
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1975SoPh...45...35L
Altcode:
High-quality photographs of the granulation obtained at seven
wavelengths in the Fe I line λ 6569.2 are presented. The granule
contrast attains a maximum considerably exceeding the continuum
value around Fe+0.05 to Fe+0.10 Å; individual granules remain easily
visible to within 5″ of the limb. At line centre only remnants of
the granulation pattern are discernible.
Title: Review of 'The Solar Chromosphere'
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1975Obs....95..148B
Altcode:
No abstract at ADS
Title: High-Resolution Photography of the Solar Chromosphere. XIII:
H&alpha Contrast Profiles of Sunspot Fibrils
Authors: Bray, R. J.
Bibcode: 1974SoPh...38..377B
Altcode:
High-resolution filtergrams of a sunspot and its surroundings, taken
at seven wavelengths in Hα with the aid of a computer-controlled
1/8 Å filter, have been used to derive the contrast of ten sunspot
superpenumbra fibrils as functions of wavelength. The observed contrast
profiles are compared with profiles calculated on the basis of three
theoretical models, namely, Beckers' (1964) `cloud' model, Athay's
(1970) `velocity' model, and a `pure Doppler shift' model. However,
none of these models in their present form account for all the observed
profiles.
Title: High-Resolution Photography of the Solar Chromosphere. XV:
Preliminary Observations in Fe I λ6569.2
Authors: Bray, R. J.; Loughhead, R. E.; Tappere, E. J.
Bibcode: 1974SoPh...39..323B
Altcode:
High-quality photographs of the quiet and enhanced network have
been obtained at the centre of Fe I λ6569.2 and in the nearby
continuum, using a 1/8 Å filter. In agreement with Dunn and Zirker,
the photospheric granules are noticeably smeared in the neighbourhood
of the enhanced network. Nevertheless, many of the bright network
elements are co-spatial with individual (smeared) photospheric granules.
Title: The solar chromosphere
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1974soch.book.....B
Altcode: 1974QB528.B7.......
No abstract at ADS
Title: Some Comments on the Photographic Subtraction Method of
Determining Chromospheric Velocities
Authors: Bray, R. J.
Bibcode: 1973SoPh...30..335B
Altcode:
The photographic subtraction formula expressing the `Doppler signal'
in terms of line-of-sight velocity is rederived and the conditions
governing its validity are carefully stated. By appealing to the
observed profiles of individual bright and dark mottles it is shown
that, in the case of Hα observations of the quiet chromosphere,
two essential conditions are violated.
Title: High-Resolution Photography of the Solar Chromosphere. X:
Physical Parameters of Hα Mottles
Authors: Bray, R. J.
Bibcode: 1973SoPh...29..317B
Altcode:
High-resolution filtergrams of the quiet chromosphere, taken at seven
wavelengths in Hα with the aid of a computer-controlled 1/8 Å filter,
have been used to derive the contrast of ten bright and dark mottles
as functions of wavelength. The contrast profiles of bright and dark
mottles are strikingly different. They disagree with Athay's (1970)
`velocity' model but, with an appropriate choice of parameters,
can be brought into good agreement with Beckers' (1964) `cloud'
model. Comparison between observation and theory yields values for the
source function S, optical thickness t0, line broadening
parameter Δλ0, and line-of-sight velocity V for both
bright and dark mottles. The values of S and t0 obtained
for dark mottles are consistent with Beckers' (1968) spicule model.
Title: High-Resolution Photography of the Solar Chromosphere. VIII:
Computer Control of a Tunable ⅛ Å Filter
Authors: Bray, R. J.; Winter, J. G.
Bibcode: 1970SoPh...15..309B
Altcode:
Computer control of a tunable 1/8 Å filter is described. The filter
is installed in the 30-cm chromospheric telescope of the CSIRO Solar
Observatory, Culgoora.
Title: High-Resolution Photography of the Solar Chromosphere. VI:
Properties of the Bright Mottles
Authors: Bray, R. J.
Bibcode: 1969SoPh...10...63B
Altcode:
Bright chromospheric mottles observed at the Hα line centre are found
to have sizes ranging from 1450 to 4400 km and lifetimes of about
11 min. They occur in close juxtaposition to dark mottles which, at
intermediate heliocentric angles (≈ 60°), are found to be displaced
towards the limb relative to the associated bright mottles. The
magnitude of the displacement indicates a height difference of 4300
km. In conjunction with height measurements of bright mottles beyond
the limb (Loughhead, 1969), this implies that bright and dark mottles
are phenomena of the lower (≲ 3300 km) and upper (≈ 5000-7600 km)
chromosphere respectively.
Title: High-Resolution Photography of the Solar Chromosphere. IV:
Size Shape, and Evolution of the Dark Mottles
Authors: Bray, R. J.
Bibcode: 1968SoPh....5..323B
Altcode:
Using photographs of the centre of the solar disk with an effective
resolution of 1 sec of arc or better, the size, shape, and evolution
of dark mottles are studied.
Title: High-Resolution Photography of the Solar Chromosphere. II:
The Relationship between Chromospheric and Photospheric Faculae
Authors: Bray, R. J.
Bibcode: 1968SoPh....4..318B
Altcode:
No abstract at ADS
Title: High-Resolution Photography of the Solar Chromosphere. I:
The 30-cm Refractor of the C. S. I. R. O. Solar Observatory
Authors: Loughhead, R. E.; Bray, R. J.; Tappere, E. J.; Winter, J. G.
Bibcode: 1968SoPh....4..185L
Altcode:
A new telescope designed for high-resolution photography of the
chromosphere is described. It is mounted in the open air on a 15-m tower
and is provided with air suction shields to cool all surfaces exposed
to the sun's rays. The best moments for photography are selected by
a seeing monitor. The highest resolution so far attained is 0″. 75
of arc, compared with a theoretical resolution limit at Hα of 0″. 55.
Title: Buchbesprechungen über: The Solar
Granulation. (Ref. E. H. SCHRÖTER)
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1968ZA.....68..416B
Altcode:
No abstract at ADS
Title: The solar granulation
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1967sogr.book.....B
Altcode: 1967QB539.B68......
No abstract at ADS
Title: Statistics of Solar Seeing
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1966ZA.....63..101L
Altcode:
No abstract at ADS
Title: Sunspots
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1964suns.book.....B
Altcode: 1964QB525.B78......
No abstract at ADS
Title: The Helium D3 Absorption Line in the Spectra of
Chromospheric Flares. With 3 Figures in the Text
Authors: Bray, R. J.
Bibcode: 1964ZA.....60..207B
Altcode:
No abstract at ADS
Title: Isophotal Contour Maps of Sunspots
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1962AuJPh..15..482B
Altcode:
No abstract at ADS
Title: Phenomena Accompanying the Birth of Sunspot Pores
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1961AuJPh..14..347L
Altcode:
No abstract at ADS
Title: Facular Granule Lifetimes determined with a Seeing-monitored
Photoheliograph
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1961AuJPh..14...14B
Altcode:
No abstract at ADS
Title: Granulation near the Extreme Solar Limb
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1960AuJPh..13..738L
Altcode:
No abstract at ADS
Title: The Lifetime and Cell Size of the Granulation in Sunspot Umbrae
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1960AuJPh..13..139L
Altcode:
No abstract at ADS
Title: High Resolution Observations of the Granular Structure of
Sunspot Umbrae
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1959AuJPh..12..320B
Altcode:
No abstract at ADS
Title: A "seeing monitor" to aid solar observation
Authors: Bray, R. J.; Loughhead, R. E.; Norton, D. G.
Bibcode: 1959Obs....79...63B
Altcode:
No abstract at ADS
Title: Observations of Faculae bordering Small Sunspots near the Limb
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1959AuJPh..12...97L
Altcode:
No abstract at ADS
Title: Observations of Changes in the Photospheric Granules
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1958AuJPh..11..507B
Altcode:
No abstract at ADS
Title: The Lifetime of Sunspot Penumbra Filaments
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1958AuJPh..11..185B
Altcode:
No abstract at ADS
Title: The Wilson Effect in Sunspots
Authors: Loughhead, R. E.; Bray, R. J.
Bibcode: 1958AuJPh..11..177L
Altcode:
No abstract at ADS
Title: Bright regions in sunspots
Authors: Bray, R. J.; Loughhead, R. E.
Bibcode: 1957Obs....77..201B
Altcode:
No abstract at ADS
Title: The centre-limb variation of the sodium D line intensities
Authors: Bray, R. J.
Bibcode: 1956MNRAS.116..395B
Altcode:
New observations of tbe centre-limb variation of the Na D lines are
compared with the earlier observations of Shane, Allen, Houtgast,
Priester and Shcherbina-Samoilova. Central intensities' found by
the different observers agree within the experimental error. The new
measurements provide no evidence for any centre-limb variatio exceeding
I per cent for points whose residual intensity is greater than 75 per
cent, a result which agrees with Allen's conclusions but disagrees with
those of Priester and the other workers. The line cores are formed by
coherent scattering, the central intensities being formally accounted
for by a value of E of + . Various mechanisms for producing non-zero
central intensities are considered.
Title: Absorption lines in the solar spectrum: the centre-limb
variation of the sodium D-lines
Authors: Bray, R. J.
Bibcode: 1956PhDT........70B
Altcode:
No abstract at ADS
Title: The apparatus function of the Oxford solar spectroscope
Authors: Bray, R. J.
Bibcode: 1954MNRAS.114..540B
Altcode:
The apparatus function of the Oxford solar spectroscope has been
determined in the wave-length region A 5461-A 5945. Comparison with
Plaskett's determination of the core of the profile at A4320 shows
that Redman s suggestion that the linear dimensions of the profile
are independent of wave-length requires modification. Differences
between the curves at the two regions can be accounted for by the
existence of large-scale inhomogeneities of the order of 3 X Io- in the
refractive index of the prisms. The wings of the apparatus function
show a number of sharp subsidiary maxima, whose spacing is six to
seven times the spacing of the subsidiary maxima of the theoretical
diffraction pattern. They are attributed to diffraction by striae,
known to be present in the prisms.