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Shortcut to non-refereed publications
| Title: | On the Search for Transits of the Planets Orbiting Gliese 876 | |
| Authors: | Shankland, P. D.; Rivera, E. J.; Laughlin, G.; Blank, D. L.; Price, A.; Gary, B.; Bissinger, R.; Ringwald, F.; White, G.; Henry, G. W.; McGee, P.; Wolf, A. S.; Carter, B.; Lee, S.; Biggs, J.; Monard, B.; Ashley, M. C. B. | |
| Journal: | Astrophysical Journal, Vol. 653, Issue 1, pp. 700-707. | |
| Publication Date: | 12/2006 | |
| Keywords: | Stars: Planetary Systems, Planets and Satellites: General, Stars: Individual: Name: Gliese 876 | |
| DOI: | 10.1086/508562 | |
| Abstract | ||
| We report the results of a globally coordinated photometric campaign to search for transits by the P~30 day and P~60 day outer planets of the three-planet system orbiting the nearby M dwarf Gl 876. These two planets experience strong mutual perturbations, which necessitate the use of a dynamical (four-body) model to compute transit ephemerides for the system. Our photometric data have been collected from published archival sources, as well as from our photometric campaigns that were targeted to specific transit predictions. Our analysis indicates that transits by planet c (P~30 days) do not currently occur, in concordance with the best-fit i=50° coplanar configuration obtained by dynamical fits to the most recent radial velocity data for the system. Transits by planet b (P~60 day) are not entirely ruled out by our observations, but our data indicate that it is very unlikely that they occur. Our experience with the Gl 876 system suggests that a distributed ground-based network of small telescopes can be used to search for transits of very low mass M stars by terrestrial-sized planets. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | Piloting a network of small telescopes | |
| Authors: | Fadavi, M.; Verveer, A.; Aymon, J.; Merlin, D.; Situ, K.; Pennypackker, C.; Biggs, J. D.; White, G.; Gould, A.; Greenberg, G.; Hoette, V.; McCarron, K.; Archer, K.; Pino, F.; Hibbs, M.; Ford, M.; Wetsch, J. | |
| Journal: | Astronomische Nachrichten, Vol. 327, Issue 8, p.811-813. | |
| Publication Date: | 09/2006 | |
| Keywords: | telescopes, methods: observational | |
| DOI: | 10.1002/asna.200610686 | |
| Abstract | ||
| The Pilot Small Telescope Network (PSTN) is a state-of the art system of easily replicable and scalable hardware, software, servers, eXtensible Markup Language (XML) protocols, and network middleware connecting and developing a pilot array of robotic telescopes to one another and the user community. The PSTN is a developmental project that will allow growing access to these telescopes, and make available data to faculty, students and others in an environment of collaboration. The underlying goal of the PSTN is to broaden the quantity and quality of astronomical education and research, particularly with a focus on traditionally underserved populations. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | A Search for the Potentially Hazardous Asteroid 1998 OX4: Implications for a Possible Close Encounter in 2014 | |
| Authors: | Biggs, James D.; Slivkoff, Matthew | |
| Journal: | Publications of the Astronomical Society of Australia, Vol. 19, Issue 4, pp. 422-424. | |
| Publication Date: | 00/2002 | |
| Keywords: | asteroids: impacts, orbit, 1998 OX4 | |
| DOI: | 10.1071/AS02002 | |
| Abstract | ||
| Small bodies of 100-500m diameter can cause significant damage on impact with the Earth. Such objects are difficult to detect and track because they are intrinsically faint over most of their orbit. We failed to detect one such lost and potentially hazardous minor planet, 1998 OX4, during two observing sessions in 2001, January. The positions searched were those calculated by Milani et al. (2000) with their Virtual Impactors method. Using some simple assumptions we estimate the probability that we failed to detect 1998 OX4 due to it being obscured by objects in the field of our observations is <2×10-7. If the assumptions in the Virtual Impactor model are valid we conclude that an impact with 1998 OX4 is unlikely in 2014, January. Furthermore, given the relatively large area we searched it is also unlikely that this minor planet will have a very close encounter with Earth in 2014. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | Spreading the word - western style: Education and public awareness programmes at Perth Observatory | |
| Authors: | Biggs, James D. | |
| Journal: | Publications Astronomical Society of Australia, Vol. 14, no. 2, p. 214-18 | |
| Publication Date: | 08/1997 | |
| Keywords: | ASTRONOMY EDUCATION | |
| Abstract | ||
| Since the attempt to close it in 1987, Perth Observatory has undertaken many initiatives to increase community awareness of, and education in, astronomy. Factors such as geographic isolation, the desire to maintain some level of scientific output, and being a part of the Western Australian public service are both a help and a hindrance to our activities. An overview of these activities is presented with particular attention to the impact of the environmental factors mentioned above. Anecdotal and objective measures of the success of these activities are also presented along with suggestions for future initiatives. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | The ultraviolet polarization of the Crab pulsar | |
| Authors: | Graham-Smith, Dolan, J. F.; Boyd, P. T.; Biggs, J. D.; Lyne, A. G.; Percival, J. W. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 282, Issue 4, pp. 1354-1358. | |
| Publication Date: | 10/1996 | |
| Keywords: | POLARIZATION - PULSARS, INDIVIDUAL, CRAB - ULTRAVIOLET, STARS. | |
| Abstract | ||
| The linear polarization of the Crab pulsar has been observed in the ultraviolet using the High Speed Photometer on the Hubble Space Telescope. The polarization as a function of pulse phase is strikingly similar to that observed in the visible, with the same values of fractional polarization and the same swing of position angle occurring through the main and secondary pulses. The polarization pulse profile must be essentially wavelength-independent at wavelengths shorter than the infrared, as predicted by the geometric model of the emission region proposed by Smith et al. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | A Search for Radio Pulsars in Globular Clusters, Supernova Remnants and Transient X-Ray Sources | |
| Authors: | Biggs, J. D.; Lyne, A. G. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 282, Issue 2, pp. 691-698. | |
| Publication Date: | 09/1996 | |
| Keywords: | SURVEYS - PULSARS, GENERAL - SUPERNOVA REMNANTS - GLOBULAR CLUSTERS, GENERAL - X-RAYS, GENERAL. | |
| Abstract | ||
| We present the results of a targeted search for radio pulsars in globular clusters, supernova remnants (SNRs) and transient X-ray sources. 85 globular clusters, 29 SNRs and three transient X-ray sources were observed in the course of the search, during which four pulsars were found. For each object searched, the sensitivity limit is given. The four new pulsars discovered were all in globular clusters, namely PSR B1620-26 in M4, PSR B1718-19 in NGC6342, and PSR B1820-30A and B1820-30B in NGC6624. While PSR B1620-26 provides strong support for the binary evolution hypothesis for the formation of millisecond pulsars, PSR B1718-19 and B1820-30A are somewhat anomalous as they are apparently relatively young, the former pulsar and PSR B1820-30B have high magnetic fields, and all are located in old globular clusters (ages ~1010yr). Not surprisingly, the well-known pulsar PSR B0531+21 was detected in the Crab nebula SNR. The number of pulsars detected was probably limited by the finite size of pulsar emission beams, as in any survey. Other factors such as large distance, low pulsar luminosity and orbital motion may have inhibited the detection of other pulsars in globular clusters. Pulsars in SNRs and transient X-ray sources are probably less affected by these factors. Our inability to detect the former is probably due to the relatively high level of emission from the SNRs, the limited area that we observed within each target and possibly the high birth velocity of pulsars which carries them away from the centres of their remnants. Processes concerning the accretion discs of transient X-ray sources probably thwarted the detection of any potential radio pulsars in these systems. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | The Polarization of X-Ray Binaries in the Ultraviolet. I. Cygnus XR-1, 4U 0900-40, and 4U 1700-37 | |
| Authors: | Wolinski, Karen G.; Dolan, Joseph F.; Boyd, Patricia T.; Biggs, James D.; Nelson, Matthew J.; Percival, Jeffrey W.; Taylor, M.; van Citters, G. W. | |
| Journal: | Astrophysical Journal, Vol. 457, p.859 | |
| Publication Date: | 02/1996 | |
| Keywords: | POLARIZATION, STARS: INDIVIDUAL CONSTELLATION NAME: CYGNUS XR-1, STARS: INDIVIDUAL ALPHANUMERIC: 4U 1700-37, STARS: INDIVIDUAL ALPHANUMERIC: 4U 0900-40, X-RAYS: STARS | |
| DOI: | 10.1086/176781 |
| Full text available - email J Biggs | ^ Top ^ |
| Title: | A Search for a Pulsar in the Remnant of SN 1987A with the Hubble Space Telescope High-Speed Photometer | |
| Authors: | Percival, J. W.; Boyd, P. T.; Biggs, J. D.; Dolan, J. F.; Bless, R. C.; Elliot, J. L.; Nelson, M. J.; Robinson, E. L.; Taylor, M. J.; van Citters, G. W.; Wolinski, K. G. | |
| Journal: | Astrophysical Journal, Vol. 446, p.832 | |
| Publication Date: | 06/1995 | |
| Keywords: | TECHNIQUES: PHOTOMETRIC, STARS: PULSARS: INDIVIDUAL ALPHANUMERIC: SN 1987A, ULTRAVIOLET: STARS | |
| DOI: | 10.1086/175840 |
| Full text available - email J Biggs | ^ Top ^ |
| Title: | Two radio pulsars in the globular cluster NGC 6624 | |
| Authors: | Biggs, J. D.; Bailes, M.; Lyne, A. G.; Goss, W. M.; Fruchter, A. S. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 267, p. 125 | |
| Publication Date: | 03/1994 | |
| Abstract | ||
| We report the discovery and accurate timing measurements of two single radio pulsars in the globular cluster NGC 6624. PSR 1820-30A is a 5-ms pulsar that is located close to the low-mass X-ray binary 4U 1820-30. It seems that the recently reported radio detection of 4U 1820-30 with the VLA is, in fact, that of the pulsar. The observed period and period-derivative of PSR 1820-30A make it disturbingly young, and also conflict with the accretion spin-up theory unless acceleration in the cluster potential is largely responsible for the observed period-derivative. This requires that the cluster core lie much closer to the pulsar than has been believed hitherto. Such an explanation may also explain the anomalous orbital period-derivative of 4U 1820-30. PSR 1820-30B has a pulse period of 378 ms, which is unusually long for a pulsar associated with a globular cluster, and also has an unusually large inferred magnetic field. If the neutron star is primordial, then this suggests that its magnetic field has decreased only slightly, if at all, since its formation. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | Centaurus A, the core of the problem | |
| Authors: | Tingay, S. J.; Jauncey, D. L.; Preston, R. A.; Reynolds, J. E.; Meier, D. L.; Tzioumis, A. K.; Jones, D. L.; King, E. A.; Amy, S. W.; Biggs, J. D. | |
| Journal: | Australian Journal of Physics (ISSN 0004-9506), Vol. 47, no. 5, p. 619-624 | |
| Publication Date: | 00/1994 | |
| Keywords: | CENTAURUS CONSTELLATION, ELLIPTICAL GALAXIES, RADIO ASTRONOMY, RADIO GALAXIES, ACTIVE GALACTIC NUCLEI, GALACTIC RADIO WAVES, GALACTIC STRUCTURE, IMAGE RESOLUTION, RADIO JETS (ASTRONOMY), VERY LONG BASE INTERFEROMETRY | |
| Abstract | ||
| The bright, peculiar elliptical galaxy Centaurus A (NGC 5128, PKS 1322-427) was one of the first extragalactic radio sources to be optically identified (Bolton et al. 1949). At a distance of 4 Mpc, Centaurus A is the closest active radio galaxy and affords the highest linear imaging resolution (1 mas approximately equal to 0.02 pc) and hence the best prospects for studying an active nucleus close to the central radio source. We present the results of multi-epoch, 8.4-GHz, very long baseline interferometry (VLBI), imaging observations of the nucleus made over the past three years. The nucleus possesses a core-jet structure where the inner portion of the jet shows apparent linear motion with a velocity substantially less than the speed of light. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | The Crab pulsar in the visible and ultraviolet with 20 microsecond effective time resolution | |
| Authors: | Percival, J. W.; Biggs, J. D.; Dolan, J. F.; Robinson, E. L.; Taylor, M. J.; Bless, R. C.; Elliot, J. L.; Nelson, M. J.; Ramseyer, T. F.; van Citters, G. W.; Zhang, E. | |
| Journal: | Astrophysical Journal, Part 1, Vol. 407, no. 1, p. 276-283. | |
| Publication Date: | 04/1993 | |
| Keywords: | PULSARS, STELLAR SPECTROPHOTOMETRY, ULTRAVIOLET ASTRONOMY, HUBBLE SPACE TELESCOPE, LIGHT CURVE | |
| DOI: | 10.1086/172512 | |
| Abstract | ||
| Observations of PSR 0531+21 with the High Speed Photometer on the HST in the visible in October 1991 and in the UV in January 1992 are presented. The time resolution of the instrument was 10.74 microsec; the effective time resolution of the light curves folded modulo the pulsar period was 21.5 microsec. The main pulse arrival time is the same in the UV as in the visible and radio to within the accuracy of the establishment of the spacecraft clock, ± 1.05 ms. The peak of the main pulse is resolved in time. Corrected for reddening, the intensity spectral index of the Crab pulsar from 1680 to 7400 A is 0.11 ± 0.13. The pulsed flux has an intensity less than 0.9 percent of the peak flux just before the onset of the main pulse. The variations in intensity of individual main and secondary pulses are uncorrelated, even within the same rotational period. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | A long-period globular-cluster pulsar in an eclipsing binary system | |
| Authors: | Lyne, A. G.; Biggs, J. D.; Harrison, P. A.; Bailes, M. | |
| Journal: | Nature, Vol. 361, no. 6407, p. 47-49. | |
| Publication Date: | 01/1993 | |
| Keywords: | ECLIPSING BINARY STARS, GLOBULAR CLUSTERS, PULSARS, RADIO WAVES, STELLAR MAGNETIC FIELDS, STELLAR MASS ACCRETION, STELLAR MASS EJECTION, STELLAR SYSTEMS | |
| DOI: | 10.1038/361047a0 | |
| Abstract | ||
| Pulsars that are members of binary systems in globular clusters are all rapidly rotating, and it is assumed that they have been spun up by accretion from binary companions. Here we report an exception: PSR 1718-19, in the globular cluster NGC 6342, is in a 6.2-hour eclipsing binary system, but has the relatively long period of 1s. Its magnetic field is strong, about 10 exp 12 G, and its spindown age is small, about 10 Myr. Furthermore, the mass of its companion is only 0.1-0.2 solar masses. The eclipses show that the binary system is embedded in a cloud of material which must have been ejected from the companion star, although calculations suggest that the companion is well inside its Roche lobe. The pulsar's radiation may be causing expulsion of material beyond the Roche lobe, as in the ablating binary systems containing PSR-1744-24A and PSR1957 + 20, even though the incident flux at the companion is orders of magnitude smaller than in these cases. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | An analysis of radio pulsar nulling statistics | |
| Authors: | Biggs, James D. | |
| Journal: | Astrophysical Journal, Part 1, Vol. 394, no. 2, Aug. 1, 1992, p. 574-580. | |
| Publication Date: | 08/1992 | |
| Keywords: | PULSARS, RADIO STARS, STELLAR PHYSICS, CORRELATION, EMISSION SPECTRA, STELLAR ROTATION | |
| DOI: | 10.1086/171608 | |
| Abstract | ||
| Survival analysis methods are used to seek correlations between the fraction of null pulsars and other pulsar characteristics for an ensemble of 72 radio pulsars. The strongest correlation is found between the null fraction and the pulse period, suggesting that nulling is a manifestation of a faltering emission mechanism. Correlations are also found between the fraction of null pulses and other parameters that have a strong dependence on the pulse period. The results presented here suggest that nulling is broad-band and may ultimately be explained in terms of polar cap models of pulsar emission. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | The Jodrell bank 'C' pulsar survey - A survey of the northern Galactic plane for rapidly rotating pulsars | |
| Authors: | Biggs, J. D.; Lyne, A. G. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 254, Jan. 15, 1992, p. 257-263. | |
| Publication Date: | 01/1992 | |
| Keywords: | PULSARS, SKY SURVEYS (ASTRONOMY), STELLAR ROTATION, BINARY STARS, GALACTIC RADIATION, STELLAR LUMINOSITY, STELLAR SPECTRA | |
| Abstract | ||
| Nearly 1500 sq deg of the northern Galactic plane were surveyed for rapidly rotating pulsars using the 76-m Lovell telescope. The sampling rate was such that there was sufficient nominal sensitivity to detect pulsars with periods as short as 0.6 ms. To overcome the effects of dispersion, scattering, and galactic background radiation, the high frequency of 1420 MHz was used to survey the inner Galaxy, while lower frequencies of 928 and 610 MHz were used for regions further from the Galactic center. PSR 1937+21 was detected in the survey, but no new pulsars were discovered. This is consistent with the results of other recent surveys and suggests that rapidly rotating, high-luminosity pulsars are not very common in the Galactic disk. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | Main Pulse / Interpulse Correlation and Mode Changing in PSR:1055-52 | |
| Authors: | Biggs, J. D. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 246, no.2/Sep15, p. 341, 1990 | |
| Publication Date: | 09/1990 |
| Full text available - email J Biggs | ^ Top ^ |
| Title: | Meridional Compression of Radio Pulsar Beams | |
| Authors: | Biggs, J. D. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 245, no. 1/Jul1, p. 514, 1990 | |
| Publication Date: | 07/1990 |
| Full text available - email J Biggs | ^ Top ^ |
| Title: | A search for interpulses from southern pulsars | |
| Authors: | Biggs, J. D.; Lyne, A. G.; Hamilton, P. A.; McCulloch, P. M.; Manchester, R. N. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 235, Nov. 1, 1988, p. 255-260. | |
| Publication Date: | 11/1988 | |
| Keywords: | EMISSION SPECTRA, PULSARS, SOUTHERN HEMISPHERE, STELLAR RADIATION, POLAR CAPS, STELLAR ROTATION | |
| Abstract | ||
| The results of a search for interpulses and bridges of emission from 38 pulsars observable from the Southern Hemisphere are presented. A previously undetected interpulse was found in PSR 1702-19, and observations over a wide frequency range suggests that its magnetic axis is perpendicular to its rotational axis. This information, and the emission geometry of the two other interpulse pulsars in this search, suggest there is a tendency for the magnetic axis to evolve toward the rotation axis. The main pulse and interpulse of PSR 1702-19 appear to come from the center of the polar cap region. Both emit as much as 60 percent circular polarization; an amount rarely seen in any other pulse profile. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | Discovery of a binary millisecond pulsar in the globular cluster M4 | |
| Authors: | Lyne, A. G.; Biggs, J. D.; Brinklow, A.; McKenna, J.; Ashworth, M. | |
| Journal: | Nature, Vol. 332, March 3, 1988, p. 45-47. | |
| Publication Date: | 03/1988 | |
| Keywords: | BINARY STARS, GLOBULAR CLUSTERS, PULSARS, NEUTRON STARS, PULSE DURATION, X RAY BINARIES | |
| DOI: | 10.1038/332045a0 | |
| Abstract | ||
| The discovery of an 11-ms pulsar, PSR1620-26, in the closest globular cluster M4 (NGC6121) is reported. This pulsar occurs in a low-mass binary system, providing enough support for formation mechanisms in which an old neutron star is spun up to millisecond periods by accretion during an X-ray binary phase. The orbit's small eccentricity is likely to have significant implications for both the age of the millisecond pulsar and its surface magnetic field. It is concluded that the pulsar's current companion is in fact the star which was responsible for the spin-up. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | The drifting subpulses of PSR 0818-13 | |
| Authors: | Biggs, J. D.; McCulloch, P. M.; Hamilton, P. A.; Manchester, R. N. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 228, Sept. 1, 1987, p. 119-123. | |
| Publication Date: | 09/1987 | |
| Keywords: | DRIFT RATE, PULSARS, SPECTRUM ANALYSIS, STELLAR SPECTROPHOTOMETRY, RADIANT FLUX DENSITY, RADIO EMISSION | |
| Abstract | ||
| The drifting subpulses of PSR 0818-13 have been analyzed in detail using observations of individual pulses at 645 MHz. The subpulse drift is found to have a pronounced decrease in drift rate near the center of the integrated pulse profile. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | Adult Classes in Astronomy at Sydney University | |
| Authors: | O'Byrne, J. W.; White, G. L.; Harnett, J. I.; Biggs, J. D. | |
| Journal: | ASTRON. SOC. OF AUSTRALIA. PROCEEDINGS Vol. 6:4, p. 516, 1986 | |
| Publication Date: | 00/1986 | |
| Abstract | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | A study of PSR 0826 - 34 - A remarkable pulsar | |
| Authors: | Biggs, J. D.; McCulloch, P. M.; Hamilton, P. A.; Manchester, R. N.; Lyne, A. G. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 215, July 15, 1985, p. 281-294. | |
| Publication Date: | 07/1985 | |
| Keywords: | DRIFT RATE, POLARIMETRY, PULSARS, PULSE DURATION, RADIO EMISSION, CORRELATION, FREQUENCY SHIFT, PULSE TIME MODULATION, RADIANT FLUX DENSITY, STELLAR ROTATION | |
| Abstract | ||
| Observations of individual pulses from PSR 0826-34 at 645 MHz show subpulses at all longitudes. The integrated pulse profile is very wide and possesses a strong interpulse which leads the midpoint of the main double pulse by about 150° of longitude. A remarkable pattern of drifting subpulses occurs across nearly 200° of longitude, with typically five drift bands present. The drift rate shows wide variations including sign reversals, but no significant variations in the secondary period were observed. The character of integrated pulse polarization profiles at 408 and 610 MHz and the width of the integrated pulse profile are consistent with a nearly aligned rotator emission geometry with possible elongation of the emission beam. Current proposals for the drifting subpulse mechanism do not adequately describe the observed drifting subpulse behaviour. | ||
| Full text available - email J Biggs | ^ Top ^ |
| Title: | The drifting subpulses of PSR 0148-06 | |
| Authors: | Biggs, J. D.; Hamilton, P. A.; McCulloch, P. M.; Manchester, R. N. | |
| Journal: | Monthly Notices of the Royal Astronomical Society, Vol. 214, June 1, 1985, p. 47P-52P. | |
| Publication Date: | 06/1985 | |
| Keywords: | ELECTROMAGNETIC PULSES, PULSARS, RADIO SOURCES (ASTRONOMY), AMPLITUDE MODULATION, CROSS CORRELATION, DRIFT RATE, PULSE DURATION, RADIANT FLUX DENSITY | |
| Abstract | ||
| Drifting subpulses have been detected at 645 MHz in observations of individual pulses from PSR 0148-06. The integrated pulse profile has two well-resolved components. Distinct drifting subpulses are visible in the earliest component whilst, in the later component, drifting is weak. Both components have a strong periodic amplitude modulation associated with the drifting subpulses. | ||
| Full text available - email J Biggs | ^ Top ^ |
Shortcut to refereed publications
| Title: | Western Australian Astronomy Almanac 2008 (and CD) | |
| Authors: | Biggs, J. D., ed. | |
| Publisher: | Perth Observatory, Perth, WA | |
| Publication Date: | 12/2007 | |
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| Title: | Planet-Hunting, "Transit-Style" | |
| Authors: | Jayawardene B.; White G.; Blank D.; Hons A.; Verveer A. and Biggs J. | |
| Journal: | Mercury, 36, no. 2, p. 26 (2007). | |
| Publication Date: | 04/2007 | |
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| Title: | Western Australian Astronomy Almanac 2007 (and CD) | |
| Authors: | Biggs, J. D., ed. | |
| Publisher: | Perth Observatory, Perth, WA | |
| Publication Date: | 12/2006 | |
| ^ Top ^ |
| Title: | Western Australian Astronomy Almanac 2006 (and CD) | |
| Authors: | Biggs, J. D., ed. | |
| Publisher: | Perth Observatory, Perth, WA | |
| Publication Date: | 12/2005 | |
| ^ Top ^ |
| Title: | A Photometric Monitoring Campaign to Check for Planetary Transits of GJ 876 | |
| Authors: | Shankland, P. D.; Blank, D.; Laughlin, G.; Price, A.; Gary, B.; Bissinger, R.; Ringwald, F.; White, G.; Ashbey, M.; Greenhill, J.; McGee, P.; Sinclair, S.; Carter, B.; Lee, S.; Biggs, J.; Tabur, V.; Roy, A.; Santallo, R.; Kilmartin, P.; Higgins, D.; Nelson, P.; Richards, T.; Heathcote, B.; Stockdale, C.; Kereszty, Z.; .Laurent, J. dePonthiere, P.; Johnston, K. J.; Lazio, J.; .Knapp, C.; Dvorak, S.; Fleenor, M.; Case, J.; Koppelman, M.; Wells, D.; Dillon, W.; Koff, R.; James, R.; Holtzman, J.; Huziak, R. | |
| Journal: | American Astronomical Society Meeting 206, #09.08 | |
| Publication Date: | 05/2005 | |
| Abstract | ||
| Radial Velocity Observations have shown that the nearby M4 V dwarf GJ 876 is accompanied by two massive planets in a 2:1 mean motion resonance (Marcy et al 2001). Astrometric observations with HST (Benedict et al 2002) suggest that the plane of the outer planet has an inclination, i=84° ± 6°, indicating that the system is a good candidate for photometric follow-up to check for transits of the two planets. We report results from a multi-observer campaign carried out during 2004, which indicate that neither planet is currently transiting. We present dynamical models of the system which indicate that future transits of the inner planet may be observed in the future, provided that the orbital planes of the two planets possess several degrees of mutual inclination. | ||
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| Title: | Mid-IR Spectroscopy of Dusty Protostellar Disks: A Game Plan | |
| Authors: | Sitko, M. L.; Bauer, A. E.; Brafford, S. M.; Lynch, D. K.; Russell, R. W.; Grady, C. A.; Molster, F. J.; Bradley, J. P.; Calvet, N.; Hartmann, L.; Nuth, J. A., III; Hill, H. G. M.; Biggs, J. D.; Hanner, M. S. | |
| Journal: | Debris Disks and the Formation of Planets: A Symposium in Memory of Fred Gillett, ASP Conference Series, Vol. 324, Proceedings of the conference held 11-13 April, 2002 in Tucson Arizona. Edited by L. Caroff, L. J. Moon, D. Backman, and E. Praton. San Francisco: Astronomical Society of the Pacific, 2004., p.221 | |
| Publication Date: | 12/2004 | |
| Abstract | ||
| With the advent of new laboratory analytical tools and in situ detectors in space, the analysis of solids in space is on the verge of becoming a true, experimentally-based science. Here we outline a broad strategy for studying the mineralogical nature of solids in dusty protostellar disks. | ||
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| Title: | Western Australian Astronomy Almanac 2005 | |
| Authors: | Biggs, J. D., ed. | |
| Publisher: | Perth Observatory, Perth, WA | |
| Publication Date: | 11/2004 | |
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| Title: | Are we ETs? An Update on the Panspermia Hypothesis | |
| Authors: | Biggs, J. | |
| Journal: | Proceedings of the Iron and Sulphur Bacteria Workshop, Murdoch University, 11-14 February 2004, ISBW Planning Committee eds., Scott, B.; Walker, C. | |
| Publication Date: | 00/2004 | |
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| Title: | Supernova 2004S in MCG -05-16-21 | |
| Authors: | Martin, R.; Biggs, J. | |
| Journal: | IAU Circ., 8282, 1 (2004). Edited by Green, D. W. E. | |
| Publication Date: | 02/2004 | |
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| Title: | Western Australian Astronomy Almanac 2004 | |
| Authors: | Biggs, J. D., ed. | |
| Publisher: | Perth Observatory, Perth, WA | |
| Publication Date: | 12/2003 | |
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| Title: | Supernova 2003jg in NGC 2997 | |
| Authors: | Biggs, J.; Monard, L. A. G.; | |
| Journal: | IAU Circ., 8236, 3 (2003). Edited by Green, D. W. E. | |
| Publication Date: | 11/2003 | |
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| Title: | Supernova 2003jg in NGC 2997 | |
| Authors: | Martin, R.; Biggs, J. | |
| Journal: | IAU Circ., 8235, 1 (2003). Edited by Green, D. W. E. | |
| Publication Date: | 10/2003 | |
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| Title: | Western Australian Astronomy Almanac 2003 | |
| Authors: | Biggs, J. D., ed. | |
| Publisher: | Perth Observatory, Perth, WA | |
| Publication Date: | 12/2002 | |
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| Title: | Night and Day Under an Outback Sky: An astronomical adventure 2001 | |
| Authors: | Patrick S.; Biggs, J. D., eds. | |
| Journal: | Landscope Expedition Report No. 43, CALM, Perth, WA | |
| Publication Date: | 00/2002 | |
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| Title: | The Environment and Wind of the Herbig Ae Star HD 104237: HST/STIS Coronagraphic Imaging and HST/STIS and FUSE FUV spectroscopy | |
| Authors: | Danks, A.; Vieira, G.; Grady, C.; Woodgate, B.; Brown, A.; Harper, G.; Wilkinson, E.; Herczeg, C.; Sitko, M.; Bauer, A.; Biggs, J. | |
| Journal: | American Astronomical Society, 199th AAS Meeting, #60.14; Bulletin of the American Astronomical Society, Vol. 33, p.1396 | |
| Publication Date: | 12/2001 | |
| Abstract | ||
| We present HST/STIS white light coronagraphic imaging, STIS FUV low dispersion spectroscopy and FUSE moderate resolution spectroscopy supplemented by optical photometry of the nearby Herbig Ae star HD 104237. The coronagraphic data reveal a nearby star, hereafter termed HD 104237B, offset 1.4" (162 AU) from the Ae star as well as three additional bright stars more than 10" from HD 104237. All four nearby stars have magnitudes and colors, inferred from the shape of the PSF wings, characteristic of M8-M9 T Tauri stars. One of the companions varied significantly in the course of the first STIS coronagraphic imaging suite, consistent with flaring. The proximity of these stars indicate that the Herbig Ae star, hereafter termed HD 104237A, is located in a small T association. The proximity of the nearest companion to HD 104237 is consistent with the anomalously bright x-ray emission from HD 104237 originating at least partially on the companion, as originally suggested by Skinner & Yamauchi (1996). No circumstellar disk is visible in the STIS images, implying an outer disk radius below 57 AU, as expected from tidal truncation of HD 104237A disk by HD 104237B. STIS low resolution long slit spectra covering 1150-1700 Å were obtained with the 52x0.2" slit in the same orbits as the coronagraphic images. Both spectra resolve the wind in Lyman alpha, with an outer radius of at least 1.3" (150 AU) at PA=339°. We also detect molecular hydrogen emission beyond the Ly alpha emission in both spectra at PA=319 and 339°. At PA=339°, the molecular hydrogen emission extends from 1.4 to 2.0" (160-230 AU). The FUSE, HST/GHRS and STIS spectra of HD104237 show a wide range of chromospheric and transition region emission lines. All except the hottest lines, i.e. N V and O VI, show the presence of a high velocity outflow with a maximum speed of ~ -300 km s-1. The O VI 1032 Å profile shows strong H2 molecular absorptions that lead to fluorecent FUV H2 emissions. This study is part of the STIS Guaranteed Time Observation program, which is supported NASA GTO funding to the STIS Science Team in response to NASA A/O OSSA -4-84 through the HST Project at GSFC. CAG is supported through interagency transfer of funds to NOAO. A. Brown, GH, and E.W. are supported through LTSA grants NAG5-3226 and NAG5-4808. MS and A. Bauer are supported through the Ohio Space Grant program. | ||
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| Title: | 1RXS J232953.9+062814 | |
| Authors: | Biggs, J.; Walsh, S. | |
| Journal: | IAU Circ., 7749, 3 (2001). Edited by Green, D. W. E. | |
| Publication Date: | 11/2001 | |
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| Title: | Supernova 2001el in NGC 1448 | |
| Authors: | Monard, A. G.; Bock, G.; Wassilieff, A.; Biggs, J. | |
| Journal: | IAU Circ., 7720, 1 (2001). Edited by Green, D. W. E. | |
| Publication Date: | 09/2001 | |
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| Title: | Comet C/2000 W1 (Utsunomiya-Jones) | |
| Authors: | Nakano, S.; .Hale, A.; Seargent, D.; Biggs, J.; Urata, T.; Kobayashi, J.; Gilmore, A. C.; Jones, F.; Marsden, B. G. | |
| Journal: | IAU Circ., 7526, 1 (2000). Edited by Green, D. W. E. | |
| Publication Date: | 11/2000 | |
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| Title: | Comet C/2000 U5 (LINEAR) | |
| Authors: | Ticha, J.; Tichy, M.; Klinglesmith, D. A., III; Ikari, Y.; Biggs, J.; Durig, D. T. | |
| Journal: | IAU Circ., 7515, 1 (2000). Edited by Green, D. W. E. | |
| Publication Date: | 11/2000 | |
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| Title: | Supernova 1999ga in NGC 2442 | |
| Authors: | Woodings, S.; Martin, R.; Williams, A.; Biggs, J.; Verveer, A. | |
| Journal: | IAU Circ., 7316, 1 (1999). Edited by Green, D. W. E. | |
| Publication Date: | 11/1999 | |
| ^ Top ^ |
| Title: | Supernova 1999ex in IC 5179 | |
| Authors: | Martin, R.; Williams, A.; Woodings, S.; Biggs, J.; Verveer, A. | |
| Journal: | IAU Circ., 7310, 1 (1999). Edited by Green, D. W. E. | |
| Publication Date: | 11/1999 | |
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| Title: | Supernova 1999ee in IC 5179 | |
| Authors: | Williams, A.; Biggs, J.; Verveer, A. | |
| Journal: | IAU Circ., 7284, 2 (1999). Edited by Green, D. W. E. | |
| Publication Date: | 10/1999 | |
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| Title: | Supernova 1999cz in NGC 5078 | |
| Authors: | Williams, A.; Martin, R.; Woodings, S.; Livingston, C.; Biggs, J.; Verveer, A. | |
| Journal: | IAU Circ., 7214, 1 (1999). Edited by Green, D. W. E. | |
| Publication Date: | 07/1999 | |
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| Title: | Supernova 1999ca in NGC 3120 | |
| Authors: | Woodings, S.; Martin, R.; Williams, A.; Verveer, A.; Biggs, J. | |
| Journal: | IAU Circ., 7158, 1 (1999). Edited by Green, D. W. E. | |
| Publication Date: | 05/1999 | |
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| Title: | An Astronomical Experience and Abrolhous Odyssey 1999 | |
| Authors: | Kenneally, K.; Coate, K.; Biggs, J. D., eds. | |
| Journal: | Landscope Expedition Report No. 31, CALM, Perth, WA | |
| Publication Date: | 00/1999 | |
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| Title: | New Moon over the Murchison - Encounters with plants and planets, Burnerbinmah Station 1998 | |
| Authors: | Patrick S.; Biggs, J. D.; Edinger, D., eds. | |
| Journal: | Landscope Expedition Report No. 30, CALM, Perth, WA | |
| Publication Date: | 00/1999 | |
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| Title: | A critical view of the night sky: part 2 | |
| Authors: | Biggs, J. D. | |
| Journal: | SCIOS, STAWA, WA, vol 34, p. 18 | |
| Publication Date: | 00/1998 | |
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| Title: | Solar eclipse safety | |
| Authors: | Lowe, G. S.; Biggs, J. D. | |
| Journal: | SCIOS, STAWA, WA, vol 33, p. 44 | |
| Publication Date: | 00/1998 | |
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| Title: | Supernova 1998ce in MCG -4-24-19 | |
| Authors: | Woodings, S.; Martin, R.; Williams, A.; Biggs, J.; Verveer, A. | |
| Journal: | IAU Circ., 6912, 1 (1998). Edited by Green, D. W. E. | |
| Publication Date: | 05/1998 | |
| ^ Top ^ |
| Title: | A critical view of the night sky: part 1 | |
| Authors: | Biggs, J. D. | |
| Journal: | SCIOS, STAWA, WA, vol 33, p. 15 | |
| Publication Date: | 00/1998 | |
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| Title: | Under Desert Skies 1997 | |
| Authors: | Biggs, J. D., ed. | |
| Journal: | Landscope Expedition Report No. 25, CALM, Perth, WA | |
| Publication Date: | 00/1998 | |
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| Title: | Save the Premium Bubbly until 2001 | |
| Authors: | Biggs, J. D. | |
| Journal: | Australian Newspaper, p11. | |
| Publication Date: | 1997/8/28 | |
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| Title: | Supernova 1998A in IC 2627 | |
| Authors: | Williams, A.; .Woodings, S.; Martin, R.; Verveer, A.; Biggs, J. | |
| Journal: | IAU Circ., 6805, 2 (1998). Edited by Green, D. W. E. | |
| Publication Date: | 01/1998 | |
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| Title: | Only Time Will Tell | |
| Authors: | Biggs, J. D. | |
| Journal: | Weekend Australian, letters to the editor. | |
| Publication Date: | 1996/12/28 | |
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| Title: | The Polarization of the Crab Pulsar with HST | |
| Authors: | Dolan, J. F.;Boyd, P. T.; Hill, R. J.; Graham-Smith, F.; Lyne, A. G.; Biggs, J. D.; Percival, J. W.; Robinson, E. L.; van Citters, G. W. | |
| Journal: | Pulsars: problems and progress, Astronomical Society of the Pacific Conference Series, Vol. 105; Proceedings of the 160th colloquium of the International Astronomical Union held in Sydney; Australia; 8-12 January 1996; San Francisco: Astronomical Society of the Pacific (ASP); |c1996; edited by S. Johnston, M.A. Walker, and M. Bailes., p.301 | |
| Publication Date: | 00/1996 | |
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| Title: | Obituary - Candy, Michael Philip - 1928-1994 | |
| Authors: | Birch, P.; Biggs, J. | |
| Journal: | R.A.S. QUARTERLY JOURNAL V. 36, NO. 3/SEP, P. 285, 1995 | |
| Publication Date: | 09/1995 | |
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| Title: | A Search for a Pulsar in the Remnant of SN1987A with the High Speed Photometer | |
| Authors: | Dolan, J. F.; Percival, J. W.; Boyd, P. T.; Biggs, J. D.; Bless, R. C.; Elliot, J. L.; Nelson, M. J.; Robinson, E. L.; Taylor, M. J.; van Citters, G. W.; Wolinski, K. G. | |
| Journal: | American Astronomical Society, 185th AAS Meeting, #62.04; Bulletin of the American Astronomical Society, Vol. 26, p.1416 | |
| Publication Date: | 12/1994 | |
| Abstract | ||
| The High Speed Photometer on the Hubble Space Telescope observed the remnant of SN1987A on four different epochs between 1992 June 2 and 1993 November 4 in a 1600 - 7000 Å bandpass. Each observation was approximately 40 minutes in duration and used a 100 microsecond sampling time. After correcting to the barycenter of the solar system, no periodic signal was found in any data set using autocorrelation function (ACF) analyses with lags from 200 microseconds to 10 s, power spectral function (PSF) analyses with a Nyquist frequency corresponding to a period of 200 microseconds, or in trial pulse profiles obtained by binning the data modulo the frequencies of highest significance in the ACF and PSF analyses. Searches for signals with large values of dp/dt also proved negative. We estimate an upper limit of V fainter than 27 for pulsed radiation from any stellar remnant of SN1987A. | ||
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| Title: | Monitoring the interstellar scintillations of PSR 1933+16: Eight epochs from January 1992 to May 1993. | |
| Authors: | Oppenheimer, Ben R.; Salter, Chris; Biggs, Jamie; Foster, Roger; Ghosh, Tapasi | |
| Journal: | American Astronomical Society, 183rd AAS Meeting, #44.07; Bulletin of the American Astronomical Society, Vol. 25, p.1358 | |
| Publication Date: | 12/1993 | |
| Abstract | ||
| We present observations of the interstellar scintillation of the 1.4-GHz emission from pulsar PSR1933+16 taken at eight epochs between January 1992, and May 1993. Accepted theory indicates that these scintillations are due to diffraction of the emission caused by free electron clouds on scales of 106 to 108 m, and refraction of the emission caused by free electron clouds of size 1010 to 1012 m. While diffractive effects are always visible in this pulsar's emission spectra, a single refractive event was observed in July 1992. At this epoch, the characteristic tilting by refraction of scintiles in the dynamic spectra was clearly present at the commencement of the observing session, but diminished, and ultimately disappeared, over a period of two days. Our data place strong constraints on the frequency and duration of such refractive events in this object. We calculate an average CN2 for PSR1933+16 of 10-2.76 m-20/3, where CN2 is the path-length-averaged strength of turbulence in the interstellar medium. In addition, the estimated average speed of the diffraction pattern transverse to the line of sight is Viss = 176 kms-1. Our data on PSR1933+16 confirm the prediction from scintillation theory that the decorrelation bandwidth of the scintillations should be proportional to the square of the time scale of the intensity fluctuations. | ||
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| Title: | Supernova 1987A in the Large Magellanic Cloud | |
| Authors: | Bless, R. C.; Dolan, J. F.; Elliot, J. L.; Robinson, E. L.; van Citters, G. W.; Biggs, J. D.; Boyd, P.; Nelson, M. J.; Percival, J. W.; Taylor, M. J.; Wolinski, K. | |
| Journal: | IAU Circ., 5810, 2 (1993). Edited by Green, D. W. E. | |
| Publication Date: | 06/1993 | |
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| Title: | Recent Results from the High Speed Photometer | |
| Authors: | Taylor, M.; Bless, R. C.; Nelson, M.; Percival, J.; Bosh, A.; Cooke, M.; Elliot, J.; van Citters, W.; Dolan, J.; Biggs, J.; Wood, J.; Robinson, E. | |
| Journal: | Stellar photometry - Current techniques and future developments. Proceedings of the IAU Colloquium No. 136 held in Dublin; Ireland; 4-7 August 1992; Cambridge: Cambridge University Press; |c1993; edited by C.J. Butler and I. Elliott, p.356 | |
| Publication Date: | 00/1993 | |
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| Title: | HST High Speed Photometer Observations of the Crab Pulsar | |
| Authors: | Biggs, J. D.; Percival, J. W.; Bless, R. C.; Dolan, J. F.; Elliot, J. L.; Nelson, M. J.; Robinson, E. L.; Taylor, M. J.; van Citters, G. W. | Journal: | Isolated Pulsars, Proceedings of the Los Alamos workshop, held in Taos, New Mexico, February 23-28, 1992. Edited by K.A. Riper, R. Epstein and C. Ho. Cambridge: Cambridge University Press, 1993., p.197 |
| Publication Date: | 00/1993 | |
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| Title: | Main Pulse-Interpulse Correlation in PSR 1702-19 | |
| Authors: | Biggs, J. D. | |
| Journal: | Isolated Pulsars, Proceedings of the Los Alamos workshop, held in Taos, New Mexico, February 23-28, 1992. Edited by K.A. Riper, R. Epstein and C. Ho. Cambridge: Cambridge University Press, 1993., p.197 | |
| Publication Date: | 00/1993 | |
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| Title: | Performance and Capabilities of the High Speed Photometer | |
| Authors: | Percival, J. W.; Bless, R. C.; Nelson, M. J.; Taylor, M. J.; Dolan, J. F.; Biggs, J. D..; Elliot, J. L.; Bosh, A.; Cooke, M. L.; Robinson, E. L.; Wood, J. H.; van Citters, G. W. | |
| Journal: | Science with the Hubble Space Telescope, Proceedings of a ST-ECF/STScI Workshop held in Chia Laguna, Sardinia, Italy 29 June - 7 July 1992. ESO Conference and Workshop Proceedings, No. 44. Edited by Piero Benvenuti and Ethan J. Schreier. Garching near Munich: European Southern Observatory, 1992., p.359 | |
| Publication Date: | 00/1992 | |
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| Title: | The Crab Pulsar in the Visible and UV | |
| Authors: | Dolan, J. F.; Percival, J. W.; Biggs, J. D.; Robinson, E. L.; Taylor, M. J.; Bless, R. C.; Elliot, J. L.; Nelson, M. J.; Ramseyer, T. F.; van Citters, G. W.; Zhan, E. | |
| Journal: | Science with the Hubble Space Telescope, Proceedings of a ST-ECF/STScI Workshop held in Chia Laguna, Sardinia, Italy 29 June - 7 July 1992. ESO Conference and Workshop Proceedings, No. 44. Edited by Piero Benvenuti and Ethan J. Schreier. Garching near Munich: European Southern Observatory, 1992., p.359 | |
| Publication Date: | 00/1992 | |
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| Title: | HSP observations of the Crab pulsar and Z Chamaeleontis | |
| Authors: | Taylor, M.; Bless, R. C.; Wood, J. H.; Biggs, J. D.; Dolan, J. F.; Elliot, J. L.; Nelson, M. J.; Percival, J. W.;, Robinson, E. L.; van Citters, G. W. | |
| Journal: | Bulletin of the Astronomical Society of America, 24, 451. | |
| Publication Date: | 00/1992 | |
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| Title: | Main Pulse-Interpulse Correlation and Mode Changing in PSR 1055-52 | |
| Authors: | Biggs, James D. | |
| Journal: | Magnetospheric Structure and Emission Mechanics of Radio Pulsars, Proceedings of IAU Colloq. 128, held in Lagow, Poland, 17-22 June 1990. Edited by T. H. Hankins, J. M. Rankin, and J. A. Gil. Pedagogical Univ. Press, 1992., p.261 | |
| Publication Date: | 00/1992 | |
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| Title: | Meridional Compression of Radio Pulsar Beams | |
| Authors: | Biggs, James D. | |
| Journal: | Magnetospheric Structure and Emission Mechanics of Radio Pulsars, Proceedings of IAU Colloq. 128, held in Lagow, Poland, 17-22 June 1990. Edited by T. H. Hankins, J. M. Rankin, and J. A. Gil. Pedagogical Univ. Press, 1992., p.22 | |
| Publication Date: | 00/1992 | |
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| Title: | Searching for pulsars in globular clusters: The Parkes/Jodrell Bank surveys | |
| Authors: | Robinson, C.; Lyne, A. G.; Bailes, M.;Biggs, J. D.; Manchester, R. N. ; D'Amico, N. | |
| Journal: | X-ray Binaries and the Formation of Binary Millisecond pulsars: Proceedings of NATO ARW held in Santa Barbara, USA, January 1991, Kluwer, Dordrecht. | |
| Publication Date: | 00/1991 | |
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| Title: | Two Pulsars in NGC 6624 | |
| Authors: | Biggs, J. D.; Lyne, A. G.; Manchester, R. N.; Ashworth, M. | |
| Journal: | IAU Circ., 4988, 2 (1990). Edited by Green, D. W. E. | |
| Publication Date: | 04/1990 | |
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| Title: | A search for radio pulsars in globular clusters and transient X ray sources | |
| Authors: | Biggs, J. D.; Lyne, A. G.; Johnston, S. | |
| Journal: | In ESA, The 23rd ESLAB Symposium on Two Topics in X Ray Astronomy. Volume 1: X Ray Binaries p 293-299 (SEE N90-25711 19-89) | |
| Publication Date: | 11/1989 | |
| Abstract | ||
| The results of an ongoing search for pulsars in globular clusters and transient X-ray sources are presented. Since the discovery of the millisecond pulsar PSR 1821-24 in M28 one new pulsar was discovered, PSR 1620-26, in a binary system in the core of the globular cluster M4. Upper limits to pulsed emission are given for the 84 globular clusters and 3 X-ray transient sources observed. The paucity of new discoveries in globular clusters by this survey is considered. The inability to detect X-ray sources may be the result of processes related to their accretion disks. An improvement in sensitivity afforded by a planned software enhancement may reveal some pulsars in the objects observed. | ||
| ^ Top ^ | ||
| Title: | Millisecond Pulsar in M4 | |
| Authors: | Brinklow, A.; Lyne, A. G.; Biggs, J. D.; Ashworth, M. | |
| Journal: | IAU Circ., 4470, 1 (1987). Edited by Green, D. W. E. | |
| Publication Date: | 10/1987 | |
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| Title: | A continuum observation of P/Halley at 843 MHz | |
| Authors: | Biggs, J. D.; Reynolds, J. E. | |
| Journal: | NRAO Workshop: Cometary Radio Astronomy, p.41, eds. Irvine, W. M., Schloerb, F. P. & Tacconi-Garman, L. E., NRAO, Green Bank. | |
| Publication Date: | 00/1987 | |
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