Theses

  • Stockman, L.M. (1990). Unstructured Sparse Matrix Dense Vector Multiplication on the DAP. [Unpublished Master of Science Degree Project]. Queen Mary and Westfield College, University of London.

Refereed Papers

Book Articles/Chapters

  • Stockman, L.M. (2017). Monthly Sky Notes. In B. Jones (Ed.), Yearbook of Astronomy 2018 (pp. 79–141). White Owl.
  • Stockman, L.M. (2018). Monthly Sky Notes. In B. Jones (Ed.), Yearbook of Astronomy 2019 (pp. 83–146). White Owl.
  • Stockman, L.M. (2018). The Planets in 2019. In B. Jones (Ed.), Yearbook of Astronomy 2019 (pp. 76–77). White Owl.
  • Stockman, L.M. (2018). Some Events in 2019. In B. Jones (Ed.), Yearbook of Astronomy 2019 (pp. 80–82). White Owl.
  • Stockman, L.M. (2019). Monthly Sky Notes. In B. Jones (Ed.), Yearbook of Astronomy 2020 (pp. 87–182). White Owl.
  • Stockman, L.M. (2019). The Planets in 2020. In B. Jones (Ed.), Yearbook of Astronomy 2020 (pp. 78–80). White Owl.
  • Stockman, L.M. (2019). Some Events in 2020. In B. Jones (Ed.), Yearbook of Astronomy 2020 (pp. 84–86). White Owl.
  • Stockman, L.M. (2020). Monthly Sky Notes. In B. Jones (Ed.), Yearbook of Astronomy 2021 (pp. 87–178). White Owl.
  • Stockman, L.M. (2020). The Planets in 2021. In B. Jones (Ed.), Yearbook of Astronomy 2021 (pp. 78–80). White Owl.
  • Stockman, L.M. (2020). Some Events in 2021. In B. Jones (Ed.), Yearbook of Astronomy 2021 (pp. 83–85). White Owl.
  • Stockman, L.M. (2021). The Astronomers’ Stars: A Study in Scarlet. In B. Jones (Ed.), Yearbook of Astronomy 2022 (pp. 238–248). White Owl.
  • Stockman, L.M. (2021). Monthly Sky Notes. In B. Jones (Ed.), Yearbook of Astronomy 2022 (pp. 87–165). White Owl.
  • Stockman, L.M. (2021). The Planets in 2022. In B. Jones (Ed.), Yearbook of Astronomy 2022 (pp. 78–80). White Owl.
  • Stockman, L.M. (2021). Some Events in 2022. In B. Jones (Ed.), Yearbook of Astronomy 2022 (pp. 81–83). White Owl.
  • Stockman, L.M. (2022). The Astronomers’ Stars: Life in the Fast Lane. In B. Jones (Ed.), Yearbook of Astronomy 2023 (pp. 258–268). White Owl.
  • Stockman, L.M. (2022). Monthly Sky Notes. In B. Jones (Ed.), Yearbook of Astronomy 2023 (pp. 95–165). White Owl.
  • Stockman, L.M. (2022). The Planets in 2023. In B. Jones (Ed.), Yearbook of Astronomy 2023 (pp. 78–80). White Owl.
  • Stockman, L.M., Harper, D. (2022). Shining a Light on Jupiter’s Atmosphere. In B. Jones (Ed.), Yearbook of Astronomy 2023 (pp. 141–143). White Owl.
  • Stockman, L.M. (2022). Some Events in 2023. In B. Jones (Ed.), Yearbook of Astronomy 2023 (pp. 89–93). White Owl.
  • Stockman, L.M. (2023). The Astronomers’ Stars: In the Neighbourhood. In B. Jones (Ed.), Yearbook of Astronomy 2024 (pp. 298–305). White Owl.
  • Stockman, L.M. (2023). Gone But Not Forgotten: Musca Borealis. In B. Jones (Ed.), Yearbook of Astronomy 2024 (pp. 163–166). White Owl.
  • Stockman, L.M. (2023). Monthly Sky Notes. In B. Jones (Ed.), Yearbook of Astronomy 2024 (pp. 91–169). White Owl.
  • Stockman, L.M. (2023). Lunar Occultations in 2024. In B. Jones (Ed.), Yearbook of Astronomy 2024 (pp. 87–88). White Owl.
  • Stockman, L.M. (2023). The Planets in 2024. In B. Jones (Ed.), Yearbook of Astronomy 2024 (pp. 78–80). White Owl.
  • Stockman, L.M. (in preparation). The Astronomers’ Stars: The Terrible Twos. In B. Jones (Ed.), Yearbook of Astronomy 2025. White Owl.
  • Stockman, L.M. (in preparation). Gone But Not Forgotten: Anser. In B. Jones (Ed.), Yearbook of Astronomy 2025. White Owl.
  • Stockman, L.M. (in preparation). Lunar Phenomena. In B. Jones (Ed.), Yearbook of Astronomy 2025. White Owl.
  • Stockman, L.M. (in preparation). Monthly Sky Notes. In B. Jones (Ed.), Yearbook of Astronomy 2025. White Owl.
  • Stockman, L.M. (in preparation). The Planets in 2025. In B. Jones (Ed.), Yearbook of Astronomy 2025. White Owl.
  • Stockman, L.M. (in preparation). Full Moon Names: A Full Moon by any other name would shine as bright. In B. Jones & K. Evans (Eds.), Not Only Through the Telescope. White Owl.
  • Stockman, L.M. (in preparation). The Astronomers’ Stars: Taking It To Extremes. In B. Jones (Ed.), Yearbook of Astronomy 2026. White Owl.
  • Stockman, L.M. (in preparation). Gone But Not Forgotten: Argo Navis. In B. Jones (Ed.), Yearbook of Astronomy 2026. White Owl.
  • Stockman, L.M. (in preparation). The Astronomers’ Stars: Across the Spectrum. In B. Jones (Ed.), Yearbook of Astronomy 2027. White Owl.
  • Stockman, L.M. (in preparation). Gone But Not Forgotten: Corona Meridiana. In B. Jones (Ed.), Yearbook of Astronomy 2027. White Owl.
  • Stockman, L.M. (in preparation). The Astronomers’ Stars: The Inconstant Stars. In B. Jones (Ed.), Yearbook of Astronomy 2028. White Owl.
  • Stockman, L.M. (in preparation). Gone But Not Forgotten: Quadrans Muralis. In B. Jones (Ed.), Yearbook of Astronomy 2028. White Owl.
  • Stockman, L.M. (in preparation). The Astronomers’ Stars: Amateur Hour. In B. Jones (Ed.), Yearbook of Astronomy 2029. White Owl.
  • Stockman, L.M. (in preparation). Gone But Not Forgotten: Felis. In B. Jones (Ed.), Yearbook of Astronomy 2029. White Owl.
  • Stockman, L.M. (in preparation). The Astronomers’ Stars: Going Out With a Bang. In B. Jones (Ed.), Yearbook of Astronomy 2030. White Owl.
  • Stockman, L.M. (in preparation). Gone But Not Forgotten: Sceptrum Brandenburgicum. In B. Jones (Ed.), Yearbook of Astronomy 2030. White Owl.

Abstracts

Unstructured Sparse Matrix Dense Vector Multiplication on the DAP

Master of Science Degree Project, Queen Mary and Westfield College, University of London, August 1990

The DAP mentioned in the title and the abstract is the Applied Memory Technology Distributed Array Processor which is a massively parallel computer of single instruction multiple data (SIMD) architecture. The DAP 600 series machine which I used in my research had 4096 single-bit processing elements arranged in a 64 × 64 array, and was attached to a host computer, in this case a Digital Equipment Corporation VAX 8350. The host machine handled all input and output as well as data transfer to and from the DAP. The host programs were written in FORTRAN 77 and the DAP programs were written in FORTRAN-PLUS, a dialect of FORTRAN specific to the DAP.

The development and ever-increasing use of parallel computers have forced programmers to re-examine even the most basic mathematical algorithms and computational techniques in order to efficiently adapt these procedures to new computer architectures. Matrix vector multiplication is a familiar algorithm and has been implemented successfully on a variety of parallel computers. However, sparse matrices, which are common in many application areas, can be difficult to deal with in parallel because of their packed storage representations. This paper examines sixteen unstructured sparse matrix dense vector multiplication algorithms, all specifically tailored to the DAP.

Power series solutions of the polytrope equations

Monthly Notices of the Royal Astronomical Society, 303, 466–470, https://doi.org/10.1046/j.1365-8711.1999.02219.x

We derive recurrence relations for the coefficients ak in the power series expansion θ(ξ) = ∑ ak ξ2k of the solution of the Lane-Emden equation, and examine the convergence of these series. For values of the polytropic index n < n1 ~ 1.9 the series appear to converge everywhere inside the star. For n > n1 the series converge in the inner part of the star but then diverge. We also derive the series expansions for θ, ξ in powers of m = q2/3, where q = −ξ2 dθ/dξ is the polytropic mass. These series appear to converge everywhere within the star for all n ≤ 5. Finally we show that θ(ξ) can be satisfactorily approximated (~1%) by (1 − c ξ2)/(1 + e ξ2)m, and give the values of the constants determined by a Padé approximation to the series, and by a two-parameter fit to the numerical solutions.

The Astronomers’ Stars

Yearbook of Astronomy 2022, 2023, 2024

The stars are ours. Their names reflect our religions, our stories, our calendars, our histories. Some are millennia old, their very origins lost in antiquity; others are of a more recent origin. ŠAR.GAZ (Sargas, θ Scorpii) is the mighty weapon of the Mesopotamian god dAMAR.UTU (Marduk), patron of the city of Babylon. Perseus, hero and legendary founder of Mycenae, slew the Gorgon Medusa; Raʾas al-Ghūl (Algol, β Persei) marks the baleful blinking eye in the head of the ghoul. The heliacal rising of the brightest star in the night sky, Σείριος (Sirius, α Canis Majoris), predicts the onset of the hot, dry days of summer in Greece and the annual flooding of the Nile in Egypt. And Cor Caroli (α Canum Venaticorum), Latin for ‘the heart of Charles’, remembers the execution of English King Charles I in the mid-seventeenth century.

We looked for patterns in the night skies and we named the brightest stars. But some of the stars, most of the stars, evaded our ancestors’ detection. They were transient or faint or otherwise overlooked, and often it took careful and dedicated observation and measurement, sometimes over many years, to bring them into the light. These are the astronomers’ stars.

StarAstronomer(s)Year(s)Article
Anthelme’s StarVoituret Anthelme1670Going Out with a Bang
Argelander’s Second StarFriedrich W.A. Argelander1857Life in the Fast Lane
Argelander’s StarFriedrich W.A. Argelander1841Life in the Fast Lane
Babcock’s Magnetic StarHorace W. Babcock1960Taking It To Extremes
Barnard’s StarEdward E. Barnard1916Life in the Fast Lane
Becklin-Neugebauer ObjectEric E. Becklin, Gerhart Neubegauer1967Taking It To Extremes
Bessel’s Star,
Piazzi’s Flying Star
Friedrich W. Bessell,
Guiseppe Piazzi
1838,
1803
Life in the Fast Lane
Bidelman’s Helium Variable StarWilliam P. Bidelman1965Across the Spectrum
Bidelman’s Peculiar StarWilliam P. Bidelman1950Across the Spectrum
Bond’s Flare StarHoward E. Bond1976The Inconstant Stars
Boyajian’s Star, Tabby’s StarTabetha S. Boyajian2016Amateur Hour
Branchett’s ObjectDavid Branchett1981Amateur Hour
Butler’s Flare StarChristopher J. Butler1966The Inconstant Stars
Caffau’s StarElisabetta Caffau2011Across the Spectrum
Campbell’s Hydrogen StarWilliam W. Campbell1893Across the Spectrum
Cayrel’s StarRoger Cayrel2001Across the Spectrum
Chanal’s ObjectRoger Chanal1984Amateur Hour
Chèvremont’s Variable StarA. Chèvremont1897Amateur Hour
Dahlgren’s NovaElis Dahlgren1963Amateur Hour
Herschel’s Garnet StarF. William Herschel1783A Study in Scarlet
Herschel’s Ruby StarJohn F.W. Herschel1847A Study in Scarlet
Hind’s Crimson StarJohn R. Hind1845A Study in Scarlet
Hulse-Taylor PulsarRussell A. Hulse, Joseph H. Taylor1975The Terrible Twos
Innes’ StarRobert T.A. Innes1920In the Neighbourhood
Kapteyn’s StarJacobus C. Kapteyn1897Life in the Fast Lane
Kepler’s SupernovaJohannes Kepler1604Going Out with a Bang
Krzemiński’s StarWojceich Krzemiński1974The Terrible Twos
Kuwano’s Object,
Kuwano-Honda Object
Yoshiyuki Kuwano,
Minoru Honda
1979,
1978
The Inconstant Stars
Luyten’s StarWillem J. Luyten1935In the Neighbourhood
Merrill’s StarPaul W. Merrill1938Taking It To Extremes
Pearce’s StarJoseph A. Pearce1926The Terrible Twos
Persson’s StarRoger Persson2004Amateur Hour
Plaskett’s StarJohn S. Plaskett1922The Terrible Twos
Popper’s Extreme Helium StarDaniel M. Popper1942Across the Spectrum
Przybylski’s StarAntoni Przybylski1961Across the Spectrum
Roberts-Altizer VariableDorothea Klumpke Roberts,
Robert J. Altizer
1914,
1972
The Inconstant Stars
Rosino’s Object,
Rosino-Zwicky Object
Leonido Rosino,
Fritz Zwicky
1961,
1965
The Inconstant Stars
Sakurai’s ObjectYukio Sakurai1996Amateur Hour
Sanduleak’s StarNicholas Sanduleak1977Taking It To Extremes
Sanduleak-Pesch BinaryNicholas Sanduleak, Peter Pesch1991The Terrible Twos
Scholz’s StarRalf-Dieter Scholz2014In the Neighbourhood
Sneden’s StarChristopher Sneden1994Across the Spectrum
Stepanian’s StarJivan A. Stepanian1979The Inconstant Stars
Stephenson-Sanduleak Object*Charles B. Stephenson, Nicholas Sanduleak1977The Terrible Twos
Teegarden’s StarBonnard J. Teegarden2003In the Neighbourhood
Tycho’s SupernovaTycho Brahe1573Going Out with a Bang
Van Biesbroeck’s StarGeorges-Achille Van Biesbroeck1944Taking It To Extremes
van Maanen’s StarAdriaan van Maanen1917In the Neighbourhood
*The Stephenson-Sanduleak Object is better known by its catalogue name, SS433.