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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32490 results found.

  1. GRB990316: simultaneous optical observation
  2. GRB990308 not a new SGR
  3. GRB 990308a and GRB 990308b
  4. GRB990308 (Trig. 7457), optical observations
  5. GRB981220, IPN localization
  6. GRB 981220, radio observations
  7. GRB 990123, Field Photometry
  8. GRB 990217, radio observations
  9. BATSE Resumes Normal Operations
  10. BATSE Flight Anomaly
  11. GRB990123: Caltech STIS Photometry and Images
  12. GRB990123 observations
  13. GRB990123, Optical Observation
  14. GRB 990123: Discovery of the Probable Host Galaxy
  15. GRB 990123: Reduced HST Images
  16. For Immediate Posting to GCN - HST Data GRB 990123 Available
  17. GRB19990123 observations
  18. GRB 990123: Updated Keck Spectroscopy Results
  19. GRB 990123 NOT Spectrum Update
  20. GRB990123, Optical observation
  21. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  22. GRB 990123: Publicly available reduced HST images
  23. GRB 990123: New Constraints on Possible Foreground Galaxies
  24. GRB990123 Optical Observations
  25. GRB990123, Probability of gravitational lensing
  26. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  27. GRB 990123: Continued Radio Observations
  28. GRB 990123: Correction to GCN 230 - C.A. Young added to author list
  29. On the Lensing Interpretation of GRB 990123
  30. Search for Potential Images of GRB 990123
  31. Search for Potential Images of GRB 990123
  32. GRB990123, Optical BVRI Observations
  33. GRB 990123: near-infrared observations.
  34. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  35. GRB990123: NIR Observation
  36. "GRB 990123: New BV Observations"
  37. GRB 990123 Optical Follow-Up
  38. GRB 990123; Addendum to GCN 223
  39. GRB 990123: BATSE Observations
  40. GRB 990123 Keck Spectrum update
  41. GRB990123 IPN annulus
  42. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  43. GRB990123 Optical Observations
  44. GRB 990123 Spectroscopic Redshifts
  45. GRB 990123: New Optical Observations, Decay Measure
  46. GRB 990123 Optical Follow-Up
  47. GRB 990123: Possible Gravitationally Lensed Burst?
  48. GRB990123, optical observation
  49. GRB 990123 optical observations
  50. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  51. GRB 990123 radio observations
  52. GRB 990123, new radio source
  53. GRB990123, Optical observation
  54. GRB 990123: Optical Decay Slope
  55. GRB 990123 r-band photometry
  56. GRB 990123 Optical Follow-up
  57. GRB990123, early optical counterpart detection
  58. GRB990123 Optical Observation
  59. GRB 990123: Bright New Source, Possible Optical Transient
  60. GRB 990123, Radio observations
  61. SN 1999E & GRB 980919
  62. Optical Observations of GRB 981220
  63. GRB 981226: radio variable
  64. GRB981220
  65. GRB981220, Correction to GCN 179
  66. GRB981220, Optical Observations
  67. GRB 981220 Optical observations
  68. GRB 981226 Optical Observations
  69. GRB 980613: Spectroscopy of the host galaxy
  70. GRB981226, sub-millimeter observations
  71. GRB981220, sub-millimeter observations
  72. GRB 981220 and GRB 981226, optical observations
  73. GRB981226 Optical Observations
  74. GRB 981226 radio observations
  75. GRB 981226
  76. radio observations of GRB 981226
  77. GRB981220 B, R and I band observations
  78. Optical Observations of GRB981226
  79. GRB 981220:Optical Observations
  80. GRB 981220 optical R and I observations
  81. GRB981226, BeppoSAX Christmas GRB
  82. GRB 981226 - Infrared Observations
  83. GRB 981220
  84. GRB 981220, radio observations
  85. GRB 981220, radio observations
  86. GRB 981220: BeppoSAX/GRBM results
  87. GRB981220 I-band Observations
  88. GRB 981220
  89. GRB 981220 Optical Observations
  90. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  91. BeppoSAX NFI Observation of GRB980425
  92. GRB980425 Optical Follow-up
  93. GRB980425: X-ray revised positions
  94. GRB980703 Very Long Baseline Interferometry
  95. GRB970508 optical observations
  96. Optical Observations of the Host Galaxy of GRB 980519
  97. GRB980519, Optical Observations
  98. GRB980703, Host galaxy multicolor photometry
  99. GRB 980703 (NFI observations)
  100. GRB980703 optical photometry

Advanced

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