MACHO Alert 95-30: First Real-Time Observation of Extended Source Effects in Gravitational Microlensing

  title={MACHO Alert 95-30: First Real-Time Observation of Extended Source Effects in Gravitational Microlensing},
  author={Charles R. Alcock and William H. Allen and Robyn A. Allsman and David Randall Alves and Timothy S. Axelrod and Timothy S. Banks and Sylvie F. Beaulieu and Andrew Cameron Becker and Robert H. Becker and David P. Bennett and Ian A. Bond and Brian Carter and K. H. Cook and R. J. Dodd and Kenneth C. Freeman and Michael D. Gregg and Kim Griest and John B. Hearnshaw and Ana B. Heller and Mitsuhiko Honda and Jun Jugaku and S. Kabe and Shai Kaspi and Pam M. Kilmartin and Ayumi Kitamura and Orly Kovo and Matthew J. Lehner and T. Love and Dan Maoz and Simon L. Marshall and Yutaka Matsubara and Dante Minniti and Masanori Miyamoto and Jon A. Morse and Yasushi Muraki and Takashi Nakamura and Bruce A. Peterson and Mark M. Phillips and Mark Robin Pratt and Peter Quinn and I. N. Reid and M. L. Reid and David J. Reiss and A. J. Retter and Alex W. Rodgers and Wallace L. W. Sargent and H. D. Sato and Masaki Sekiguchi and Peter B. Stetson and Christopher W. Stubbs and Denis J. Sullivan and William J. Sutherland and Austin Bede Tomaney and Thor Vandehei and Yoshiyuki Watase and D. L. Welch and Toshifumi Yanagisawa and Masanori Yoshizawa and Ph. Yock},
  journal={The Astrophysical Journal},
We present analysis of MACHO Alert 95-30, a dramatic gravitational microlensing event toward the Galactic bulge whose peak magnification departs significantly from the standard point-source microlensing model. Alert 95-30 was observed in real time by the Global Microlensing Alert Network (GMAN), which obtained densely sampled photometric and spectroscopic data throughout the event. We interpret the light-curve fine structure as indicating transit of the lens across the extended face of the… Expand

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