Department of Physics
Associate Professor Philip Yock
- Elementary particle physics
Elementary particle physics
Despite its widespread use, today’s Standard Model of physics raises conceptual questions of naturalness, is not free of inconsistencies with observations, and includes unproven conjectures. To a sceptical eye, the model appears surprisingly complicated. Alternatives to the Standard are therefore being studied. Hadron production in high-energy photon-photon interactions provides a natural testing ground for these models. Experimental means for realising such interactions are being explored, including plasma-wakefield acceleration.
In 1969 Phil Yock proposed the first gauge theory of strong interactions, and the concepts of dually charged quarks, charge neutrality of bound states, and nuclear interactions as a residual effect of the quark binding interaction. Today’s Standard Model was subsequently built on these concepts.
Since the first planet was discovered orbiting a star other than the Sun in 1995, many “exoplanets” have been found. Some are similar to planets in our solar system, others are distinctly different. Some orbit red or brown dwarfs, others are composed largely of carbon or diamond, and still others are roaming freely between stars in the galaxy. Several were found from New Zealand by a NZ/Japan collaboration known as “MOA” using a gravitational microlensing technique conceived by Einstein. MOA uses the world’s largest telescope dedicated to gravitational microlensing, and a suite of more than twenty telescopes around the globe for follow-up observations. Future plans include yet more telescopes and a space mission for the next decade.
Phil Yock co-founded the collaboration in astrophysics between Japan and NZ with Yasushi Muraki of Japan in 1987. Recent publications include more than 150 authors from more than 50 institutions, 20 observatories and 10 countries
“The scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful. If nature were not beautiful, it would not be worth knowing, and if nature were not worth knowing, life would not be worth living.” Henri Poincaré.
Selected recent publications
- “MOA-2011-BLG-274L : the first free-floating planet with a measured mass”, with F. Abe et al, MNRAS (in preparation)
- “Perspective on particle physics”, Philip Yock, Rutherford Journal (in press)
- “Extending the planetary mass function to Earth mass by microlensing at moderately high magnification”, with F. Abe et al, MNRAS 431, 2975-2985 (2013)
- “Quarter century of astrophysics with Japan”, NZ Science Review 69(3), 61-70 (2012)
- "Unbound or distant planetary mass population detected by gravitational microlensing", with T. Sumi et al, Nature 473, 349-352 (2011)
- “A sub-Saturn mass planet, MOA-2009-BLG-319Lb”, with N. Miyake et al, ApJ 728,120 (2011)
- “Frequency of solar-like systems and of ice and gas giants beyond the snowline from high magnification microlensing events in 2005-2008”, with A. Gould et al, ApJ 720, 1073-1089 (2010)
- “Plasma wakefield collider at the LHC?”, CERN Courier, June 2009, p32 (2009)
- “Census of exoplanets in orbits beyond 0.5 AU via space-based microlensing”, with David Bennett et al, White paper to the Astro-2010 PSF Science Frontier Panel, arXiv:0902.3000 (2009)
- “Science case for PILOT III: The nearby Universe”, with J. Lawrence et al, PASA 26, 415-438 (2009)
- “Extreme microlensing event OGLE-2007-BLG-224: Terrestrial parallax observations of a thick disc brown dwarf”, with A. Gould et al, ApJL 698, L147-L151 (2009)
- “Gamma-gamma interaction: Critical test of the Standard Model”, invited paper 2008 Solvay conference, Int. J Mod. Phys. A24, 3276-3285 (2009)
- “Low-mass planet with a possible sub-stellar-mass host in microlensing event MOA-2007-BLG-192”, with D. Bennett et al, ApJ 684, 663-683 (2008)
- “Discovery of a Jupiter/Saturn analog with gravitational microlensing”, with B.S. Gaudi et al, Science 319, 927-930 (2008)
- “MOA-cam3: a widefield mosaic CCD camera for a gravitational microlensing survey from New Zealand”, with T. Sako et al, Exp. Astron. 22, 51066 (2008)
- “Planet finding”, NZ Geographic 81 (Sept/Oct), 76-85 (2006)
- “Detecting Earth-like planets from Antarctica by gravitational microlensing”, Acta Astronomica Sinica 47(4), 410-417 (2006)
- “Microlens OGLE-2005-BLG-169 implies cool Neptune-like planets are common”, with A. Gould et al, ApJL 644, L37-L40 (2006)
- “Determination of stellar shape in the microlensing event MOA-2002-BLG-33” , with N. Rattenbury et al, A&A 439, 645-650 (2005)
- “Science programs for a 2m class telescope at Dome C”, with M. Burton et al, PASA 22, 199-235 (2005)
- “Search for low-mass exoplanets by gravitational microlensing at high magnification”, with F. Abe et al, Science 305, 1264-1266 (2004)
- “Probing the atmosphere of a solar-like star by galactic microlensing”, with F. Abe et al, A&A 411, L493-L496 (2003)
- “Electro-strong interaction and high Q2 events at HERA”, Int J Theor Phys 41, 1591-1595 (2002)
- “Planetary microlensing at high magnification”, with N. Rattenbury et al, MNRAS 335, 159-169 (2002)
- “Observations from Australasia using the gravitational microlensing technique”, PASP 104, 35-44 (2000)
Selected publications from last century
- “Observation of the halo of the edge-on galaxy IC5249”, with F. Abe et al, AJ 118, 261-272 (1999)
- “MACHO alert 95-30: First real-time observation of extended source effects in gravitational microlensing”, with C. Alcock et al, ApJ 491, 436-450 (1997)
- “Search for cosmic rays from southern supernova remnants”, with W.H. Allen et al, Proc 24th Int Conf Cosmic Rays 2, 447 (1995).
- "Upper limits on TeV gamma-ray emission from Centaurus A, Vela X-1, Centaurus X-3, and Circinus X-1", with W.H. Allen et al, Astrophys.J.405:554-558 (1993)
- “Search for gamma rays from supernova 1987A at energies greater than 100 TeV”, with I. A. Bond et al, Phys. Rev. Lett. 60, 1110 (1988)
- “Search for TeV gamma rays from SN 1987A during December 1987 and January 1988”, with I.A. Bond et al., Phys.Rev.Lett.61:2292 (1988)
- “Search for antiprotons in cosmic rays”, with A. Rao, Europhys Lett 3, 1049-1052 (1987).
- “Heavy cosmic rays at sea level”, Phys Rev D 34, 698-706 (1986)
- “Ionization discrimination in helium-oxygen spark chambers”, with M. Ashburn et al, NIM 169, 121-124 (1980).
- “Search for fractional charge in tungsten”, with G. Putt, Phys Rev D 17, 1466-1467 (1978)
- “Cosmic ray telescope used to search for massive and/or fractionally charged particles”, with C. Alcock et al, NIM 115, 245-252 (1974).
- “Theory of highly charged subnuclear particles”, Annals of Physics (NY), 61, 315-328 (1970)
- “Unified field theory of quarks and electrons”, Int J Theor Phys 2, 247-254 (1969)
- “Analysis of photo-production of vector mesons”, with U. Maor, Phys Rev 148, 1542-1551 (1966)